Practice Questions

Question 1

A woman with sickle cell disease (Hb-SS) wants to have a child with her husband, who has sickle cell trait (Hb-SA). What are their chances of having a child that also has sickle cell disease?

Answer 1

50%

Question 2

How will you determine the exact hematologic diagnosis of someone with suspected sickle cell disease?

Answer 2

Hemoglobin electrophoresis with quantitative percentage of Hb F

Question 3

You are in clinic seeing a patient of yours that you recently diagnosed with sickle cell anemia. You review his medication list, which includes the following: HCTZ (hydrochlorothiazide), atenolol, hydroxyurea, and a multivamin. When you ask him, he states he has a hard time taking pills like he should, and wants to know if he needs to be taking all of them anyway. You tell him that while all of these medicines are important, the one that is most important in helping manage his sickle cell disease is which medicine?

Answer 3

hyroxyurea

Question 4

Hydroxyurea helps manage sickle cell disease by what mechanism?

Answer 4

increasing hemoglobin F in red blood cells

note - hydroxyurea’s MOA: inhibits ribonucleotide reductase, leading to decreased DNA synthesis

Question 5

common side effect of hydroxyurea

Answer 5

severe myelopsuppression

Question 6

What supplement would you recommend to a patient with sickle cell disease?

Answer 6

folic acid

Question 7

You are working in the emergency room and go to evaluate a 20 year old man whose chief complaint is pain, fever, and shortness of breath. In reviewing his history, you discover that he has sickle cell disease. Which of the following lung problems is most closely associated with sickle cell disease and therefore his most likely diagnosis?

Answer 7

acute chest syndrome

Question 8

You are with your six year old sister at school, picking her up from class to take her to her eye appointment. Her teacher is questioning your reason for taking her from class, stating “No child should have a reason to see an eye doctor at that young of an age! I think you two are going to play hooky instead!” You very patiently explain that your sister has sickle cell disease and even at her age, she needs to be screened for which of the following?

Answer 8

retinal detachment

Question 9

You take your friend who has sickle cell disease to the ER because of increasing pain in his hands, knees, and ribs that wasn’t responding to over the counter medications. While you were in the car and while your friend is in obvious pain, he cries, “I don’t know why this keeps happening to me!” You respond by comforting him, but to yourself, you think of one of the actual mechanisms of his bony pain given his diagnosis of sickle cell disease. Which of the following is the most likely underlying mechanism?

Answer 9

bone marrow hyperplasia

Question 10

You are working the night shift in the hospital and get a transfer from an outside hospital who “may or may not have a leukemia or lymphoma”. You review the large stack of records, which includes several pages of vital signs, medication distribution, and various nutritional and occupational therapy consults, but see very little documented medical information from physicians. Finally, near the bottom of the stack of records, you see reports that include a complete blood count, electrolytes, and an inpatient progress note in handwriting that is very difficult to read. You are able to interpret that the patient had no palpable lymphadenopathy or splenomegaly, but not much else. Even though you have not rotated on the hematology/oncology or leukemia service yet, which physical exam finding will be important to perform in this patient, based upon his suspected diagnosis of leukemia or lymphoma, and what you know about the embryonic development of humans?

Answer 10

hepatosplenomegaly assessment

Question 11

You are working in the Emergency Room during the graveyard shift when a Level 1 trauma is called in. The call from EMS states that a 51 year old man driving a mini Cooper was in a head-on collision with a car being driven by a 92 year old who was mistakenly going north on I-40 South. You are given the name and date of the birth of the patient and immediately begin pulling up his information on the electronic medical record while you wait to hear more. It appears that he has a history of coronary artery disease and has had one stent placed to his left anterior descending artery, has type II diabetes that appears to be poorly controlled, and also has hypertension and hypercholesterolemia. While you are going through his multiple medical problems, the EMS technician tells you that the patient has been intubated in the field for airway protection, put in a cervical stabilizer collar, and has two large bore peripheral IVs through which normal saline is being administered “wide open”. This is for his critically low blood pressure, which is 60/30, which EMS tells you is due to the large amount of blood the patient has lost due to his critical injuries which include severe abdominal trauma and a possible splenic laceration. After hanging up, you continue to prepare for the patient’’s arrival in the ER. You call the blood bank and tell them to have several units of packed red blood cells on hand for aggressive volume resuscitation. What blood type do you tell them to have available for this patient so is transfusions may begin upon arrival?

Answer 11

O

Question 12

For this same level 1 trauma patient, you have been administering packed red blood cells vigorously to support his blood pressure, which has now improved to 110/70. He is afebrile. You have already contacted Trauma Surgery to come evaluate the patient for his possible splenic laceration and internal bleeding. Per their recommendations, you have begun to administer fresh frozen plasma, as they do not have time to wait for the coag studies to return before whisking him off to the operating room. He remains intubated and sedated, however his oxygen requirements on the ventilator have begun to increase. You reexamine him and see no signs of volume overload, such has increased jugular venous distension or pedal edema. You repeat another chest x-ray and compare it to the one that you got upon arrival to confirm placement of the endotracheal tube. This second chest x-ray now reveals new bilateral infiltrates. You call the cardiology fellow to perform an emergent transthoracic echocardiogram to evaluate his ejection fraction, to assess for signs of heart failure. However, you are worried that the echo will be normal since he has no signs of volume overload on exam as mentioned above. Of the potential explanations for his current symptoms, which is the most common cause of transfusion related death?

Answer 12

transfusion related acute lung injury (TRALI)

Question 13

You are currently working in an academic center and are course director for the medical school’s second year Heme/Lymph course. In a desperate effort to get every student interested in hematology, you arrange for them to all get their blood drawn so they may review their CBCs as well as their peripheral blood smears. Before releasing these results to the students, you must first review all 120 CBCs. This includes reviewing the total white blood cell count, hemoglobin, MCV and RDW, platelet count, and peripheral blood differential. Which of the following differentials below would be consistent with a normal finding?

Answer 13

50% neutrophils, 30% lymphocytes, 8% monocytes, 7% eosinophils, 5% basophils

Question 14

You are rotating on the cardiology service and are taking care of a patient who has had a mechanical valve replacement. His hemoglobin is low, at 9 g/dl, and the attending would like to get a hematology consult to further evaluate his anemia. You call in the consult, but in the interim order some labs to evaluate what you think is the likely cause of his anemia, which is intravascular extracellular hemolysis due to shearing by the mechanical valve. Which is the correct pattern of hemolysis labs for this patient?

Answer 14

Elevated LDH, decreased haptoglobin, elevated bilirubin

Question 15

You are camping over the summer and while there get caught in a rainstorm which leaves you wet and cold for several days. Upon returning home, you visit your primary care provider for some upper respiratory symptoms you are having. You are started on an antibiotic, azithromycin, and sent home, but then are somewhat alarmed to receive a call from the on-call physician that night, informing you that some “immature” cells were seen circulating in your blood. Which is the cell type that would be reasonable to see in a peripheral blood differential consistent with infection, and not malignancy?

Answer 15

band

Question 16

A 25 year-old female is evaluated for symptoms of fatigue and brittle nails. She reports no obvious unusual bleeding such as hematemesis or melena. She is otherwise healthy and has no chronic medical conditions. She does endorse that she has had heavy menstrual periods since age 13. A complete blood count is obtained and reveals a normal white blood cell and platelet count. Her hemoglobin is 7.3 g/dL and her hematocrit is 22.9%. Her RBC count is 3.49 x 106. The RDW is 19.1. You suspect iron deficiency. Which of the following are most likely to represent the values in her iron profile? For reference, the normal ranges are: serum iron 40 – 160 TIBC 230 – 500 Ferritin 20 -200 % Saturation 15 -50

Answer 16

Serum iron = 14, TIBC = 390, Ferritin = 12, % saturation = 5

[low serum iron, normal TIBC, LOW FERRITIN, low % sat]

Question 17

You are working in the pathology department and are reviewing some reports that have popped off the flow cytometry machine. You hear footsteps rapidly approaching, and then Dr. Beaty flies by, telling you over his shoulder to “bring the flow cytometry report for the B cell (mumbling something unintelligible as he races on by)”. You review the reports in front of you and select the report that shows cellular expression of which of the following antigens?

Answer 17

CD10, CD19, CD20, CD79a

Question 18

You are visiting your sister who is eight months pregnant. After catching up on how she’’s feeling, she wants to know what you are learning about currently in medical school. You discuss with her a little hematology, especially about how difficult the hemoglobin-oxygen dissociation curve is to understand. She, however, finds this fascinating, and asks you how her baby is able to get oxygen before he is able to breathe. Which of the following statements would be a correct response to her question?

Answer 18

Fetal hemoglobin has a higher affinity for oxygen than adult hemoglobin, with a curve more to the left

Question 19

A patient of Mediterranean ancestry was given primaquine to protect against malaria before going on a vacation overseas. The patient rapidly develops a hemolytic anemia due to a mutation in an enzyme involved in which pathway?

Answer 19

Hexose monophosphate shunt / pentose phosphate pathway

note - G6PD deficiency

Question 20

A reduction in the metabolism of which amino acid can lead to elevated levels of homocysteine levels in the blood?

Answer 20

methionine

Question 21

A young male is brought to the emergency department with severe pain in his legs, arms, and back. He has had similar episodes every few months for the past several years. Blood analysis reveals anemia and odd looking, elongated red blood cells. The underlying cause for the shape of these red blood cells is which of the following?

Answer 21

Increased hydrophobic interactions between hemoglobin molecules in the deoxygenated state

Question 22

A 35 year old male comes for his scheduled course of ABVD. He was diagnosed with stage IIB Hodgkin disease and has now received 3 treatments at 2 week intervals. He has already noticed improvement in his cervical lymphadenopathy and his night sweats have gone away. He is currently asymptomatic except for some mild fatigue. A CBC today shows a WBC of 3.0 (normal 4.5 - 10.5), ANC of 1.2 (normal > 1.5), Hb of 11 (normal 14 - 16), MCV of 110 (normal 80 - 100), RDW of 22 (normal < 14.5), and platelets of 110K (normal 150K to 450K). Which of the following terms best describes his current CBC?

Answer 22

pancytopenia

Question 23

The same 35 year old male as in previous question comes for his scheduled course of ABVD. He was diagnosed with stage IIB Hodgkin disease and has now received 3 treatments at 2 weeks intervals. He has already noticed improvement in his cervical lymphadenopathy and his night sweats have gone away. He is currently asymptomatic except for some mild fatigue. His CBC today shows a WBC of 3.0 (normal 4.5 to 10.5), Hb of 11.0 (normal 14 - 16), MCV of 110 (normal 80 - 100), RDW of 22 (normal < 14.5), and platelets of 110K (normal 150K to 450K). This represents a steady decline over the last month. What is the most likely cause of his abnormal counts?

Answer 23

Bone marrow suppression from chemotherapy

Question 24

You are seeing a patient in clinic who has recently been diagnosed with Hodgkin lymphoma. He is here for a follow up appointment to discuss his treatment options, and to follow up on the results of his CT scans and bone marrow biopsy. His CT scans revealed some pathologically enlarged lymph nodes along the right cervical and right hilar regions, as well as in the right inguinal regions. Bone marrow biopsy results showed normal trilineage hematopoiesis. Based upon these findings, what stage of disease does this patient have?

Answer 24

stage 3

Question 25

A 55 year old man comes to the ED with chest pain. Evaluation reveals extensive coronary artery disease. He has an area of his heart with markedly decreased mobility, consistent with an old myocardial infarction, but also has diffuse hypokinesis and the ejection fraction is decreased to half of normal. He has smoked 2 packs per day since his teens except for a brief period of about one year when he received treatment for Hodgkin lymphoma. He is 6 feet tall and weighs 255 pounds. He has been disabled due to a back injury after a motor vehicle accident 15 years ago. He goes to see his attorney to discuss how his prior chemotherapy injured his heart. Which of the following agents that he received is most likely to have caused his cardiomyopathy (diffuse hypokinesis)?

Answer 25

doxorubicin (adriamycin)

Question 26

You are deciding on a treatment regimen for one of your patients. She is a 30 year old woman diagnosed with Hodgkin lymphoma, stage IIIB. She also has a long history of asthma and takes the leukotriene inhibitor Singulair and inhalers as needed. You are thinking of giving her ABVD but are worried about her pulmonary status. Which of the following drugs would you consider holding because of her pulmonary disease?

Answer 26

bleomycin

Question 27

Which one of the following is useful to distinguish Hodgkin lymphoma from almost all types of non- Hodgkin lymphoma (excluding anaplastic large cell lymphoma)?

Answer 27

presence of Reed-Sternberg cells (CD15+, CD30+)

Question 28

Which one of the following is the MOST important in determining the prognosis of patients with Hodgkin lymphoma?

Answer 28

stage of disease

Question 29

In general, what information, besides the diagnosis, should a physician provide in order to obtain a patient's informed consent to treatment?

Answer 29

The nature, purpose, risks of harm, and potential benefits of both the proposed treatment, of other treatment options, and of no treatment

Question 30

You are working in the Emergency Room when you go to see a 65 year old woman whose chief complaint is fatigue. Upon further evaluation, she states that she has been having low grade fevers and bleeding from her gums. On exam, she is pale and slightly short of breath at rest. She is found to be pancytopenic and subsequently gets admitted to the inpatient service. As part of her evaluation, a bone marrow biopsy is done. The interpretation of her bone marrow biopsy is that she has acute myelogenous leukemia. Which bone marrow biopsy findings would be most consistent with her diagnosis?

Answer 30

80% cellularity, 70% blasts [hypercellular, >20% blasts]

Question 31

You are on the hematology consult service and go to evaluate a patient who has leukocytosis. He is a 47 year old veteran with no significant past medical history who presented to the local VA with fatigue. His CBC abnormalities subsequently prompted transfer here. In reviewing his CBC, you note that his total white cell count is 293K, his hemoglobin is low at 12.0, and his platelets are elevated at 450K. Because his white cell count is high, you examine his differential. This reveals 58% neutrophils, 10% bands, 1% lymphocytes, 2% monocytes, 10% basophils, 2% eosinophils, 7% metamyelocytes, 5% myelocytes, 3% promyelocytes, and 2% blasts. Additional studies have been ordered but are pending. What is the most likely diagnosis for this patient?

Answer 31

chronic myelogenous leukemia (CML)

Question 32

You are at a family reunion when one of your distant cousins approaches you to reintroduce herself and "catch up on old times". She introduces you to her daughter, who is 7 years old and in the second grade. Her mother cautions you that she thinks her daughter may be getting a cold, because normally she is very active and would love to be running around in the park where the family reunion is, but for the last several days she has been more lethargic and quiet. In point of fact, she is found setting on a park bench playing with her doll listlessly, instead of running around with the other children her age. You also note that she appears pale and has a fair amount of bruising on her arms and legs. You tell your distant cousin that it would be wise to have her daughter evaluated by a physician. Were the child to have a malignancy, what would be the most likely one based upon her age?

Answer 32

acute lymphoblastic leukemia (ALL)

Question 33

You are taking care of a patient with sarcoma who is admitted for his first round of chemotherapy. The patient is scared about initiating treatment after being counseled about all of the potential side effects that could occur. As part of his chemotherapy regimen he will be receiving high doses of ifosfamide. You reassure the patient, and explain to him that one of the "chemotherapy" drugs that he will be receiving is actually a medication to help protect him from the side effects specifically associated with ifosfamide. Which medication is used to protect patients from a common side effect associated with ifosfamide?

Answer 33

Mesna

Question 34

A 53-year old male has lump near his shoulder of one week duration. On physical examination, there is an enlarged, non-tender, supraclavicular lymph node and enlargement of the Waldeyer ring of oropharyngeal lymphoid tissues. There is no hepatosplenomegaly. A CBC is normal except for mild normocytic normochromic anemia. A lymph node biopsy demonstrates replacement of normal architecture by lymphoid cells with irregular nuclei containing prominent nucleoli. Phenotypically, the lymphoid cells express positively CD19, CD20, and CD10; negatively for CD3, CD5, and TdT. Which of the following is the most likely diagnosis?

Answer 34

Diffuse large B cell lymphoma

Question 35

You are seeing a patient in clinic who needs to be evaluated for lymphadenopathy in the left cervical and right axillary regions. She was treated with two courses of antibiotics with no improvement in her nodes. Other than the lymphadenopathy, she really otherwise feels well. You confirm these areas of lymphadenopathy on exam, and do not appreciate any hepatosplenomegaly. You schedule her for an excisional biopsy of one of her nodes, and review the pathology report several days later. The excisional lymph node biopsy reveals multiple small cleaved cells, with less than five centroblasts per high powered field. FISH analysis reveals t(14;18). What is her most likely diagnosis, which is confirmed on the second page of the pathology report?

Answer 35

follicular lymphoma

Question 36

A 41-year-old male has had fevers with chills and rigors for the past 2 weeks. On physical examination, his temperature is 39.7°C. CBC shows hemoglobin 13.9 g/dL, hematocrit 40.5%, MCV 93fL, platelets 210,000/mm3, WBC 35,750/mm3 with 70% segmented neutrophils, 10% band neutrophils, 2% metamyelocytes, 3% myelocytes, 10% lymphocytes, and 5% monocytes. A bone marrow biopsy specimen is 90% cellular with M:E ratio of 12, and showing marked increase in myeloid precursors at all stages of maturation. These findings are likely caused by which of the following conditions?

Answer 36

t(9;22) BCR-ABL rearrangement

Question 37

You are seeing a patient of yours in clinic who is 70 years old and has chronic lymphocytic leukemia. He was treated for his CLL with cytotoxic chemotherapy in the past, but has not had any treatment for almost nine months. Despite that fact, he remains mildly pancytopenic. He has been hospitalized frequently for recurrent infections, which occur because his neutrophil count remains consistently less than 500. What intervention could you give him to help his neutrophil count remain higher, and therefore hopefully prevent further hospitalizations?

Answer 37

filgrastim (G-CSF)

Question 38

A 13-year-old boy has complained of worsening shortness of breath for the past week. In the past two days, several large ecchymoses have appeared on the right thigh and left shoulder. Chest X-ray demonstrates a widened mediastinum and bilateral pleural effusions. CBC shows: Hemoglobin 10.2 g/dL Hematocrit 30.5% MCV 96 fL Platelets 45,000/mm3 WBC 43,990/mm3. Examination of the peripheral blood shows numerous immature blasts that lack cytoplasmic granules and Auer rods. Flow cytometry is most likely to reveal expression of which of the following antigens on the circulating blasts?

Answer 38

CD3, CD34, TdT

Question 39

You are taking care of a 74 year old Caucasian male who has been recently diagnosed with stage IV non-small cell lung cancer. He was treated with 4 cycles of carboplatin/paclitaxel, and as his primary oncologist, you wish to continue with maintenance therapy erlotinib. Which of the following adverse effects should be counseled on, based upon what you know about this class of drugs?

Answer 39

acneiform rash

Question 40

Which of the following is the mechanism of action of fluorouracil on neoplastic cells?

Answer 40

inhibition of thymidylate synthetase activity

Question 41

A 62 year old man is being treated with methotrexate for squamous cell carcinoma of the neck. Leucovorin is added to the regimen because it does which of the following?

Answer 41

Bypasses methotrexate-induced toxicity in normal cells

Question 42

A 23 year old man with testicular cancer is undergoing chemotherapy including cisplatin, bleomycin, and vinblastine. Administration of 0.9% saline is essential to minimize the occurrence of which of the following adverse events?

Answer 42

renal tubular toxicity (from cisplatin)

Question 43

A 15 year old boy with acute lymphoblastic leukemia develops paresthesias, footdrop, and ileus after chemotherapy. Which of the following drugs is most likely to be responsible for these adverse events?

Answer 43

vincristine

Question 44

Intestinal epithelial cells are highly susceptible to damage by cancer chemotherapeutic agents because of which of the following?

Answer 44

high percentage of cells in the growth fraction

Question 45

An 18 year old man comes to the physician for a physical examination before entering college. He played on his high school football team and received a collegiate athletic scholarship. He says, "I hope to play professionally and must improve my performance any way I can." Physical examination shows no abnormalities. Laboratory studies show an increased erythrocyte count. Which of the following is the most likely cause of this laboratory finding?

Answer 45

erythropoietin

Question 46

A previously healthy 43 year old woman comes to the physician because of a 2 month history of abdominal bloating and fullness. Abdominal examination shows mild distention with a questionable fluid wave and shifting dullness. Pelvic ultrasonography shows a 4x4 cm right ovarian mass with an internal echo pattern highly suggestive of ovarian cancer. Examination of tissue from the mass obtained on biopsy shows infiltration by malignant cells. Following operative resection, combination chemotherapy including carboplatin is initiated. Inhibition of which of the following is most likely to occur with this drug in this patient?

Answer 46

DNA replication [note - platinums cross-link DNA]

Question 47

You are rotating on the general medicine service and caring for a 76 year old female admitted with confusion. She has hypertension, diabetes, coronary artery disease, and COPD for which she is chronically on 2 L of oxygen by nasal cannula. Her medication list is rather extensive and includes atenolol, lipitor, metformin, insulin, aspirin, lisinopril, and combivent, amongst others. During the course of her hospital stay her mental status worsens and she begins to develop epistaxis, gingival bleeding, and oozing from prior peripheral IV and blood draw sites. Her urine culture later grows E coli. Her PT is prolonged at 25 seconds, her PTT is prolonged at 50 seconds, her fibrinogen is low at 83, and her D dimers are elevated at 7.6. Aside from appropriate blood product support, what is the best way to treat her coagulopathy?

Answer 47

treat her urosepsis

Question 48

For this same 76 year old woman on the general medicine service, what stage of coagulopathy does she appear to have clinically, and how does this affect her overall survival?

Answer 48

Stage 3 DIC with an associated 60% chance of mortality

Question 49

You are working in the MICU and are taking care of a patient with acute myelogenous leukemia who was transferred last night with febrile neutropenia. He is currently intubated and sedated and is on levophed for blood pressure support. His antibiotics have been broadened according to the febrile neutropenia algorithm and cultures are pending. His am labs reveal a WCC of 0.2, Hb 7.6, and platelets 4K. Furthermore, his PT is 23.5 (high), INR is 2.1 (high), PTT is 35 (high), D dimers are 17.3 (high), and fibrinogen is 70 (low). What blood product will you administer to specifically improve his fibrinogen?

Answer 49

cryoprecipitate

Question 50

For this same patient in the MICU with AML, what blood product will you administer to help both the PT/INR and PTT?

Answer 50

fresh frozen plasma (FFP)

Question 51

For this same patient in the MICU with AML, which additional medication will help his coagulopathy?

Answer 51

vitamin K

Question 52

You are just starting your first third year rotation on the wards and pick up a patient with a history of hypertension and diabetes who is currently on hospital day #3 for a recently diagnosed DVT. His current medical regimen includes a beta blocker, insulin, warfarin, and unfractionated heparin. His coag studies are as follows: PT 12.1 (normal), INR 1.1 (normal), and PTT of 65 (high). Which of his medications is causing the abnormality with his PTT?

Answer 52

unfractionated heparin

Question 53

You are working in the outpatient clinic and are seeing a patient with multiple chronic medical problems, including COPD, diabetes, coronary artery disease, and a prior pulmonary embolism. His labs today reveal an elevated cholesterol level, an elevated Hb A1c, and an INR of 2.7. PTT is normal. Which anticoagulant is responsible for the increase in his INR?

Answer 53

warfarin

Question 54

You are working in the outpatient clinic and see a patient who was recently diagnosed with a DVT in the Emergency Room. They are presenting for their first follow up after that hospitalization. In reviewing her records, you see that she was started on enoxaparin. Which coagulation profile would most fit with this medication?

Answer 54

PT normal, INR normal, PTT normal

Question 55

A 50 year old man was diagnosed with diffuse large B cell lymphoma. He underwent intensive chemotherapy, and a complete remission was achieved for 7 years. He now reports fatigue and recurrent pulmonary and urinary tract infections over the past four months. Physical examination shows no masses, lymphadenopathy, or hepatosplenomegaly. CBC shows hemoglobin 8.7; MCV 88, platelets 67K, and WCC 2.3 with 15% neutrophils, 33% lymphocytes, 35% monocytes, 2% eosinophils. A bone marrow biopsy specimen shows 90% overall cellularity with many immature cells, including ringed sideroblasts, megaloblasts, hypolobated megakaryocytes, and myeloblasts. Karyotypic analysis shows 5q deletions in many cells. Which of the following is most likely now to have occurred in this patient?

Answer 55

myelodysplasia related to therapy for the previous tumor

Question 56

A 60 year old woman has had headaches and dizziness for the past 5 weeks. She has been taking cimetidine for heartburn and omeprazole for ulcers. On physical exam, she is afebrile and normotensive, and her face has a plethoric to cyanotic appearance. There is mild splenomegaly, but no other abnormal findings. Lab studies show hemoglobin 21.7, plateets 400K, and WCC 30K with 85% neutrophils, 10% lymphocytes, and 5% monocytes. The peripheral blood smear shows abnormally large platelets and nucleated RBCs. The serum epo level is undetectable, but the ferritin level is normal. Which of the following is most characteristic of the natural history of this patient's disease?

Answer 56

marrow fibrosis with extramedullary hematopoiesis

Question 57

A 69 year old woman complains of increasing back pain for one month. On physical examionation, there is tenderness over the lower back, but no kyphosis or scoliosis. A radiograph of the spine shows a partial collapse of T11 and several 0.5 - 1.5 cm lytic lesions with a rounded "soap-bubble" appearance in the thoracic and lumbar vertebrae. A bone marrow biopsy is performed, and a smear of the aspirate is shown in the figure. Which of the following is the most likely laboratory finding in this patient?

Answer 57

Bence Jones proteins in the urine [this is associated with plasma cell dyscrasias]

Question 58

A 45 year old man has experienced recurrent fevers and a 6 kg weight loss over the past five months. On physical examinaton, his temperature is 37.5 degrees Celsius, and he has cervical lymphadenopathy. The patient reports that the adenopathy becomes very tender after he drinks a six pack of beer. A lymph node biopsy specimen shows effacement of the nodal architecture by a population of small lymphocytes, plasma cells, eosinophils, and macrophages. Which of the following additional cell types, which stains positively for CD15, is most likely to be found in this disease?

Answer 58

Reed-Sternberg cell

Question 59

A 30 year old woman has had a constant feeling of lethargy since childhood. On physical exam, she is afebrile and has a pulse of 80, RR of 15, and BP of 110/70. The spleen tip is palpable, but there is no abdominal pain or tenderness. Lab studies show a hemoglobin of 11.7, platelets of 159K, and WCC of 5.4. The peripheral blood smear shows spherocytosis. The circulating RBCs show an increased osmotic fragility. An inherited abnormality in which of the following RBC components best accounts for these findings?

Answer 59

Membrane cytoskeletal protei

Question 60

A 60 year old man has developed widespread ecchymoses over the skin in the past month. His medical history includes a diagnosis of mucinous adenocarcinoma of the rectum. On physical exam he appears cachectic and pale. An abdominal CT shows multiple hepatic masses. Lab studies show prothrombin time of 30 seconds, PTT of 55 seconds, platelet count of 15K, fibrinogen of 75, and D dimer levels that are very elevated. Which of the following morphologic findings is most likely to be present on examination of the peripheral blood smear?

Answer 60

Schistocytes

Question 61

A 5 year old boy has had a history of easy bruising and blood in his urine since infancy. Physical exam shows no organomegaly. He has several ecchymoses of the skin on the lower extremities. Lab studies show hemoglobin 13.1, platelets 287K, WCC 6.8, PT 13 seconds, PTT 54 seconds, and less than 1% factor VIII activity measured in plasma. If he does not receive transfuions of recombinant factor VII concentrate, which of the following manifestations of this illness is most likely to ensue?

Answer 61

Hemarthroses

Question 62

A 54 year old woman sees her physician because of sudden onset of headaches and photophobia. This condition has been worsening for the past 2 days. On physical exam, she has a temperature of 38 degrees Celsius and is disoriented. CBC shows a hemoglobin of 11.2, MCV of 94, platelets of 32K, and WCC of 9.9. The peripheral blood smear shows schistocytes. The serum BUN is 38 and the creatinine is 3.9. Which of the following is the most likely diagnosis?

Answer 62

Thrombotic thrombocytopenic purpura

Question 63

A 39 year old woman sees her physician because she has experienced abdominal pain and intermittent low-volume diarrhea for the past 3 months. On phsical exam, she is afebrile. A stool sample is positive for occult blood. A colonoscopy is performed, and biopsy specimens from the terminal ileum and colon show microscopic findings consistent with Crohn''s disease. Because she has failed to respond to medical therapy, surgery is warranted, and part of the colon and terminal ileum are removed.. She is transfused with 2 units of pRBCs during surgery. Several weeks later, she appears healthy, but complains of easy fatigability. On investigation, CBC findings show a hemoglobin of 10.6, MCV of 118, platelets of 378K, and WCC of 9.8. The reticulocyte count is 0.3%. Which of the following is most likely to produce these findings?

Answer 63

Vitamin B12 deficiency

Question 64

You are working in the Emergency Room and go to see a patient whose history is notable for a DVT diagnosed three weeks ago. He was started on dalteparin and presents today with an acute onset of shortness of breath. On exam he is tachypneic at rest and is requiring supplemental oxygen to maintain an oxygen level over 92%. Which blood test will you obtain in order to see if the patient is appropriately anticoagulated?

Answer 64

anti-factor Xa activity

Question 65

A 10-month-old boy with hemoglobin SS disease is brought to the emergency department by his parents because of severe pain in his feet for 2 hours. He appears acutely ill and is crying. Vital signs are normal except for a pulse of 160/min. Physical examination shows splenomegaly and edematous, tender feet. Laboratory studies show a hemoglobin concentration of 7 g/dL and a reticulocyte count of 12%. A peripheral blood smear shows target cells, poikilocytes, and sickled erythrocytes. Which of the following processes most likely caused the sickled erythrocytes in this patient?

Answer 65

Spontaneous polymerization of hemoglobin S upon deoxygenation

Question 66

The graph shows the oxygen dissociation curve of hemoglobin A for a healthy individual. Which of the following curves best represents the dissociation curve for the same individual after extensive physical training at high altitudes?

Answer 66

C

Question 67

The P50 is defined as the partial pressure of oxygen (in mm Hg) required to saturate half of the hemoglobin O2 binding sites in a sample of whole blood. In blood from a healthy adult, the P50 is approximately 26 mm Hg when equilibrated with a mixture of 16% O2/5% CO2/79% N2. Which of the following manipulations will cause the P50 of the sample to increase?

Answer 67

Equilibrating it with 16% O2 / 12% CO2 / 72% N2

Question 68

Three days after taking an anti-inflammatory medication that includes phenacetin, a 23 year old African-American man passes dark reddish brown urine. He is surprised by this because he has been healthy all his life and has had no major illnesses. On PE he is AF and there are no remarkable findings. CBC shows a mild normocytic anemia, but the peripheral blood smear shows precipitates of denatured globin (Heinz bodies) with supravital staining and scattered “bite cells” in the population of RBCs. Which of the following is the most likely diagnosis?

Answer 68

Glucose-6-phosphate dehydrogenase deficiency

Question 69

A 9 year old boy living in Uganda has had increasing pain and swelling on the right side of his face over the past 8 months. On physical examination, there is a large, nontender mass involving the mandible, which deforms the right side of his face. There is no lymphadenopathy and no splenomegaly, and he is afebrile. A biopsy of the mass is performed. Microscopically, the specimen is composed of intermediate-sized lymphocytes with a high mitotic rate. A Chromosome analysis shows a 46 XY, t(8;14) karyotype in these cells. The hemoglobin is 13.2, platelets 272K, and WCC is 5.8. Infection with which of the following is most likely to be causally related to the development of these findings?

Answer 69

Epstein-Barr virus

Question 70

A 34 year old man has experienced multiple nosebleeds along with bleeding gums for the past month. On examination, his temperature is 37.3 degrees Celsius. He has multiple cutaneous ecchymoses. Laboratory studies show a hemoglobin of 8.5, platelets 13K, and WCC of 52.1. Peripheral blood differential shows 5% neutrophils, 5% bands, 2% myelocytes, 83% blasts, 3% lymphocytes, and 2% monocytes. Examination of his peripheral blood smear shows the blasts have delicate nuclear chromatin along with fine cytoplasmic azurophilic granules. These blasts are CD 33(+). Which of the following morphologic findings is most likely to be present on his peripheral blood smear?

Answer 70

Auer rods

Question 71

A 70 year old man has experienced increasing fatigue for the past 6 months. On physical examination, he has nontender axillary and cervical lymphadenopathy, but there is no hepatosplenomegaly. The hematologic work-up shows a hemoglobin of 9.5, MCV 90, platelets 120K, and WCC of 42K. The peripheral blood smear shows a monotonous population of small, round, mature looking lymphocytes. Flow cytometry shows these cells to be CD19(+), CD5(+), and TdT(-). Which of the following is most likely to be seen with cytogenetic and molecular analysis of the cells in the patient's blood?

Answer 71

Clonal rearrangement of immunoglobulin genes

Question 72

A 4 year old boy has appeared listless for about one week. He now complains of pain when he is picked up by his mother, and he exhibits irritability when his arms or legs are touched. In the past two days, several large ecchymoses have appeared on the right thigh and left shoulder. CBC shows a hemoglobin of 10.2, MCV 96, platelets 45K, and WCC 13.9. Examination of the peripheral blood smear shows blasts that lack peroxidase-positive granules, but contain PAS-positive aggregates and stain positively for TdT. Flow cytometry shows the phenotype of blasts to be CD19(+), CD3(-), and surface immunoglobulin (-). Which of the following is the most likely diagnosis?

Answer 72

Acute lymphoblastic leukemia

Question 73

In an experiment, cell samples are collected from the bone marrow aspirates of patients who were diagnosed with lymphoproliferative disorders. Cytogenetic analyses are performed on these cells, and a subset of the cases is found to have the BCR-ABL fusion gene from the reciprocal translocation t(9;22). The presence of this gene results in increased tyrosine kinase activity. Patients with which of the following conditions are most likely to have this gene?

Answer 73

Chronic myelogenous leukemia

Question 74

A 64 year old man has inguinal, axillary, and cervical lymphadenopathy. The nodes are firm and nontender. A biopsy specimen of a cervical node shows a histologic pattern of nodular aggregates of small, cleaved lymphoid cells and larger cells with open nuclear chromatin, several nucleoli, and moderate amounts of cytoplasm. A bone marrow biopsy specimen shows lymphoid aggregates of similar cells with surface immunoglobulin that are CD10(+), but CD5(-). Karyotyping of these lymphoid cells indicates the presence of t(14;18). What is the most likely diagnosis?

Answer 74

follicular lymphoma

Question 75

The figure skater Sonja Henie, who won gold medals at the 1928, 1932, and 1936 Winter Olympic Games, became progressively fatigued in her late 50s. On physical examination , she had palpable nontender axillary and inguinal lymph nodes, and the spleen tip was palpable. Laboratory studies showed hemoglobin, 10.1 g/dL; hematocrit, 30.5%; MCV,90 μm³; platelet count, 89,000/mm³;and WBC count, 31,300/mm³. From the peripheral blood picture shown in the figure, which of the following is the most likely diagnosis?

Answer 75

Chronic lymphocytic leukemia

Question 76

A 22-year-old university student reports easy fatigability of 2 months'' duration. On physical examination, she has no hepatosplenomegaly or lymphadenopathy. Mucosal gingival hemorrhages are noted. CBC shows hemoglobin, 9.5 g/dL;hematocrit, 28.2%; MCV, 94 μm³ platelet count, 20,000/mm³; and WBC count, 107,000/ mm³. A bone marrow biopsy specimen shows that the marrow is 100% cellular with few residual normal hematopoietic cells. Most of the cells in the marrow are large, with nuclei having delicate chromatin and several nucleoli. The cytoplasm of these cells has azurophilic, peroxidasepositive granules. Which of the following is the most likely diagnosis?

Answer 76

Acute myelogenous leukemia

Question 77

For the past 6 months, a 35-year-old woman has experienced an excessively heavy menstrual flow each month. She also has noticed increasing numbers of pinpoint hemorrhages on her lower extremities in the past month. Physical examination shows no organomegaly or lymphadenopathy. CBC shows hemoglobin of 14.2 g/dL, hematocrit of 42.5%, MCV of 91 μm³, platelet count of 19,000/mm³, and WBC count of 6950/mm³. On admission to the hospital, she has melena and is given a transfusion of platelets, but her platelet count does not increase. An emergency splenectomy is performed, and her platelet count increases. Which of the following describes the most likely basis for her bleeding tendency?

Answer 77

Destruction of antibody-coated platelets by the spleen

Question 78

A 69-year-old, previously healthy woman has been feeling increasingly tired and weak for 4 months. On physical examination, she is afebrile. There is no hepatosplenomegaly or lymphadenopathy. Laboratory studies show hemoglobin of 9.3 g/dL, platelet count of 250,600/mm³ and WBC count of 6820/mm³. The appearance of the peripheral blood smear is shown in the figure. Which of the following condition s should be suspected as the most likely cause of these findings?

Answer 78

Gastrointestinal blood loss

Question 79

A 65-year-old man diagnosed with follicular non Hodgkin''s lymphoma is treated with chemotherapy. He develops fever and cough. On examination, there are bilateral pulmonary rales. A chest radiograph shows diffuse interstitial infiltrates. A shell vial assay of sputum is positive for cytomegalovirus. He develops scleral icterus. Laboratory studies show hemoglobin, 10.3 g/dL; hematocrit, 41.3%; MCV, 101 μm³; WBC count, 7600/mm³ and platelet count 205,000/mm³. His serum total bilirubin is 6 mg/dL, direct bilirubin is 0.8 mg/dL, and LDH is 1020 U/L. Coombs's test is positive. Which of the following is the most likely mechanism for his anemia?

Answer 79

Binding of IgM to red blood cells

Question 80

A 12-year-old boy has a history of episodes of severe abdominal and back pain since early childhood. On physical examination, he is afebrile, and there is no organomegaly. Laboratory studies show hemoglobin of 11.2 g/dL, platelet count of 194,000/mm³ and WBC count of 9020/mm³. The peripheral blood smear shows occasional sickled cells, nucleated RBCs, and Howell-Jolly bodies. Hemoglobin electrophoresis shows 1% hemoglobin A2, 6% hemoglobin F, and 93% hemoglobin S. Hydroxyurea therapy is found to be beneficial in this patient. Which of the following is the most likely basis for its therapeutic efficacy?

Answer 80

Increase in production of hemoglobin F

Question 81

A 73-year-old man has been healthy all his life. He takes no medications and has had no major illnesses or surgeries. For the past year, he has become increasingly tired and listless, and he appears pale. Physical examination shows no hepatosplenomegaly and no deformities. CBC shows hemoglobin,9.7 g/dL; hematocrit, 29.9%; MCV, 69.7 mm³; RBC count, 4.28 million/mm³; platelet count, 331,000/mm ; and WBC count, 5500/mm³. Which of the following is the most likely underlying condition causing this patient''s findings?

Answer 81

Occult malignancy

Question 82

Three days after taking an anti-inflammatory medication that includes phenacetin, a 23-year-old African-American man passes dark reddish brown urine. He is surprised by this because he has been healthy all his life and has had no major illnesses. On physical examination, he is afebrile, and there are no remarkable findings. CBC shows a mild normocytic anemia, but the peripheral blood smear shows precipitates of denatured globin (Heinz bodies) with supravital staining and scattered "bite cells" in the population of RBCs. Which of the following is the most likely diagnosis?

Answer 82

Glucose-6-phosphate dehydrogenase deficiency

Question 83

In an epidemiologic study of anemias, the findings show that there is an increased prevalence of anemia in individuals of West African ancestry. By hemoglobin electrophoresis, a subset of individuals of this ancestry are found to have increased hemoglobin S levels. The distribution of infectious illnesses is correlated with the prevalence of hemoglobin S in this population. Which of the following infectious agents is most likely to account for these observations?

Answer 83

Plasmodium falciparum

Question 84

A 41-year-old woman sees her physician because of a 2-week history of multiple ecchymoses on her extremities after only minor trauma. She also reports feeling extremely weak. Over the previous 24 hours, she has developed a severe cough productive of yellowish sputum. On physical examination, her temperature is 38.4°C, and she has diffuse crackles on all lung fields. Laboratory studies show hemoglobin, 7.2 g/dL; hematocrit, 21.4%; MCV, 88 μm³; platelet count, 35,000/mm³; and WBC count, 1400/mm³ with 20% segmented neutrophils, 1% bands, 66% lymphocytes, and 13% monocytes. The reticulocyte count is 0.1%. Given these laboratory findings, which of the following historical findings would be most useful in determining the cause of her condition?

Answer 84

Exposure to drugs

Question 85

A clinical study of patients with hemoglobinopathies reveals that some of these patients developed episodes of acute chest, back, and abdominal pain; recurrent infections with Streptococcus pneumoniae; and chronic anemia as children and adults. They experienced none of these problems as infants, however. The presence of which of the following types of hemoglobin during infancy most likely provided protection from complications of their hemoglobinopathy?

Answer 85

F

Question 86

A 42-year-old woman has had nosebleeds, easy bruising, and increased bleeding with her menstrual periods for the past 4 months. On physical examination, her temperature is 37°C, pulse is 88/min, respirations are 18/min, and blood pressure is 90/60 mm Hg. She has scattered petechiae over the distal extremities. There is no organomegaly. Laboratory studies show hemoglobin of 12.3 g/dL, hematocrit of 37%, platelet count of 21,500/mm³ and WBC count of 7370/mm³ A bone marrow biopsy specimen shows a marked increase in megakaryocytes. The prothrombin and partial thromboplastin times are within the reference range. What is the most likely diagnosis?

Answer 86

Idiopathic thrombocytopenic purpura

Question 87

A 12-year-old boy experienced sudden onset of severe abdominal pain and cramping accompanied by chest pain, nonproductive cough, and fever. On physical examination, his temperature is 39°C, pulse is 110/min, respirations are 22/ min , and blood pressure is 80/50 mm Hg. He has diffuse abdominal tenderness, but no masses or organomegaly. Laboratory studies show a hematocrit of 18%. The peripheral blood smear is shown in the figure. A chest x-ray shows bilateral pulmonary infiltrates. Which of the following is the most likely mechanism for initiation of his pulmonary problems?

Answer 87

increased RBC adhesion to endothelium

Question 88

A clinical study of patients who inherit mutations that reduce the level of spectrin in the RBC membrane cytoskeleton shows an increased prevalence of chronic anemia with splenomegaly. For many patients, it is observed that splenectomy reduces the severity of anemia. This beneficial effect of splenectomy is most likely related to which of the following processes?

Answer 88

Decrease in trapping of RBCs in the spleen

Question 89

A 50-year-old man has had headache, dizziness, and fatigue for the past 3 months. His friends have been commenting about his increasingly ruddy complexion. He also has experienced generalized and severe pruritus, particularly when showering. He notes that his stools are dark. On PE, he is afebrile, and his BP is 165/90. There is no hepatosplenomegaly or lymphadenopathy. A stool sample is positive for occur blood. CBC shows Hb 22.3m hematocrit 67.1%, MCV 94, platelets 453K, and WBC count 7800. The serum erythropoietin level is very low. What is the most likely diagnosis?

Answer 89

Polycythemia vera

Question 90

A 63-year old woman experiences a burning sensation in her hands and feet. 2 months ago, she had an episode of swelling with tenderness in the right leg, followed by dyspnea and right-sided chest pain. On PE, the spleen and liver now appear to be enlarged. CBC shows Hb 13.3m Hct 40.1%, MCV 91, platelets 657K, and WBC 17,400. The peripheral blood smear shows abnormally large platelets. What is the most likely diagnosis?

Answer 90

Essential thrombocythemia

Question 91

A 61-year-old man reports a history of back pain for 5 months. He has recently developed a cough that is productive of yellow sputum. On PE, he is febrile, and diffuse rales are heard on auscultation of the lungs. He has no lymphadenopathy or splenomegaly. Lab studies include a sputum culture that grew Strep pneumo. The serum creatine level is 3.7, and the BUN is 35. There are lytic bone lesions in the skull on radiograph. During his hospitalization, a bone marrow biopsy is performed. What is the biopsy specimen most likely to show?

Answer 91

Numerous plasma cells

Question 92

A 23-year-old, previously healthy man has experienced malaise and a low-grade fever and sore throat for 2 weeks. On PE, he is febrile, and he has pharyngeal erythema without exudation. There is tender cervical, axillary, and inguinal lymphadenopathy. Labs show Hb 12.2, Hct 36.6%, platelets 190K, and WBC count 8940. Which of the following is the most likely risk factor for the patient's disesae?

Answer 92

Close personal contact (kissing) with his date

Question 93

A 65-year-old man sees his physician because he has experienced fatigue, a 5-kg weight loss, night sweats, and abdominal discomfort for the past year. On PE, he has marked splenomegaly; there is no lymphadenopathy. Lab studies show Hb 10.1, Hct 30.5%, MCV 89, platelets 94K, WBC count 14,750 with 55% segmented neutrophils, 9% bands, 20% lymphocytes, 8% monocytes, 4% metamyelocytes, 3% myelocytes, 1% eosinophils, and 2 nucleated RBCs per 100 WBCs. The peripheral blood smear also shows teardrop cells. The serum uric acid level is 12. A bone marrow biopsy shows extensive marrow fibrosis and clusters of atypical megakaryocytes. What is more likely to account for the enlargement of this patient's spleen?

Answer 93

extramedullary hematopoiesis

Question 94

A 48yo man visits his physician for a routine health maintenance exam. He has no complaints other than worrying about getting older and having cancer. PE shows that he is afebrile and normotensive. There is no hepatosplenomegaly or lymphadenopathy. Labs show a total serum protein level of 7.4 and albumin level of 3.9. Serum calcium and phosphorous levels are normal. Urinalysis shows no Bence Jones proteinuria. Hb is 13.6, platelet count is 301K, and WBC count is 6630. A serum protein electrophoresis shows a small spike of gamma-globulin, which is determine by immunoelectrophoresis to be IgG kappa. A bone marrow specimen shows normal cellularity with maturation of all cell lines. Plasma cells constitute about 4% of the marrow. What is the most likely dx?

Answer 94

Monoclonal gammopathy of undetermined significance

Question 95

A 63yo man has noticed a lump in his neck for 2 months. Exam reveals a group of 3 discrete nontender R posterior cervical lymph nodes, and a mass of enlarged R axillary lymph nodes. Chest and abdominal CT scans show mediastinal lymphadenopathy and hepatosplenomegaly. A cervical lymph node biopsy reveals abundant large CD15+ and CD30+ binucleate cells with prominent acidophilic nucleoli, scattered within a sparse lymphocytic infiltrate. What is molecular analysis of this lesion most likely to reveal?

Answer 95

Clonal EBV integration in the large cells

Question 96

A 62yo man goes to the ED in an obvious state of inebriation. He is well known there because this scenario has been repeated many times over the years. On PE, he is afebrile. The spleen tip is palpable, and liver edge is firm. Labs show Hb 8.2, Hc 25.1%, MCV of 107, platelets 135K, and WBC count 3920. The peripheral blood smear shows prominent anisocytosis and macrocytosis. Polychromatophilic RBCs are difficult to find. A few of the neutrophils show 6-7 lobes. What is the most likely explanation of these findings?

Answer 96

Nuclear maturation defects resulting from impaired DNA synthesis

Question 97

A clinical study is performed involving adult patients diagnosed with microangiopathic hemolytic anemia. The patients did not have diarrhea. The patients had schistocytes present on peripheral blood smears. Some of these patients were found to have a deficiency of a metalloprotease known as ADAMTS-13. Which condition do these ADAMTS-13 deficient patients have?

Answer 97

thrombotic thrombocytopenic purpura

Question 98

A 21yo woman known to have protein C deficiency develops recurrent pulmonary thromboembolism and is placed on anticoagulant therapy. 2 weeks after initiation of this therapy, she has a sudden change in mental status and experiences difficulty speaking and swallowing. A cerebral angiogram shows a distal left middle cerebral artery occlusion. Labs show Hb 13, platelets 65K, WBC count 5924, PT 12, PTT 51. The anticoagulant therapy is discontinued. Which of the following pharmacologic agents used as an anticoagulant in this patient are most likely to have caused these findings?

Answer 98

heparin

Question 99

A 45yo woman has experiences episodes of blurred vision and headaches for the past 6 months. She has had worsening confusion with paresthesias over the past 3 days. On PE, she is febrile, pulse 100, RR 20, and BP 80/50. Petechial hemorrhages are noted over her trunk and extremities. Lab findings include Hb 10.9, Hct 34%, MCV 96, platelets 28K, and WBC count 8500. Fragmented RBCs are noted on her peripheral smear. BUN is 40 and creatinine is 3.1. Which of the following is most likely underlying cause of her findings?

Answer 99

Prescence of antibodies against won Willebrand's factor metalloproteinase

Question 100

A 49 year old man comes to the outpatient clinic because of a 3 week history of ringing in his ears, stomach pain, and nausea. His past medical history is significant for chronic back pain, for which he has been taking high doses of aspirin. The physical examination shows epigastric tenderness. Which of the following describes the mechanism of action of aspirin?

Answer 100

Irreversible inhibition of cyclooxygenase (COX)-1 and COX-2

Question 101

A 6 year old boy is brought to the pediatrician by his mother because of fatigue and shortness of breath when playing with his friends. Family history is significant for a sibling who died of hydrops fetalis. Physical examination is notable for mucosal pallor. A complete blood count and peripheral smear are shown. Which of the following is the most likely cause of this patient’s anemia?

Answer 101

Alpha thalassemia

Question 102

A 5 year old boy is brought to the emergency department by his mother because of bone and joint pain and recurrent nosebleeds. The patient’s spleen is palpable below the costal margin, and conjunctival pallor is noted. A peripheral blood smear demonstrates lymphoblasts, and immunostaining of a bone marrow aspirate confirms a disproportionately high number of terminal deoxynucleotidyltransferase positive cells. The patient is started on a drug that requires coadministration with leucovorin to prevent myelosuppression and gastrointestinal damage. Which of the following letters in the table represents the enzyme targeted by the drug most likely given to this patient?

Answer 102

B

Question 103

A 69 year old man is diagnosed with chronic myelogenous leukemia. Therapy with imatinib is started. Which of the following most accurately describes the cancer protein inhibited by this drug?

Answer 103

Constitutively active tyrosine kinase

Question 104

A 28 year old man comes to the office with a 2 day history of yellowing of the eyes and dark urine. He reports that his brother has had similar episodes in the past but not his sister. Current medications include primaquine, which he began 2 days ago in preparation for an upcoming trip. On physical examination, there is mild conjunctival pallor and scleral icterus. There is no palpable lymphadenopathy or organomegaly. Laboratory tests show a hemoglobin of 12 g/dL and a hematocrit of 36%. Decreased levels of which of the following molecules is most likely in this patient?

Answer 104

Reduced nicotinamide adenine dinucleotide phosphate (NADPH)

Question 105

A researcher is performing molecular analysis on different forms of hemoglobin drawn from various blood vessels. The researcher isolates a type of hemoglobin in which the molecule’s alpha1 and beta2 chains are tightly stabilized by salt bonds. From which type of blood vessel did the investigator likely isolate this type of hemoglobin?

Answer 105

peripheral capillaries (because this is where we will have deoxygenated hemoglobin; tightly stabilized means Taut formation of Hb, means deoxygenated

Question 106

A professional cyclist wants to maximize his performance by enhancing his conditioning. He decides to move to Leadville, Colorado (elevation 10,000 ft), and trains there for three months. Which of the following changes is most likely to occur in this cyclist one week after arriving at this high altitude?

Answer 106

Rightward shift of the hemoglobin dissociation curve (promote unloading of oxygen to the tissues)