UWorld 2017

Question 1

Complication of Chronic Granulomatous Disease

Answer 1

Recurrent suppurative infections with Catalase-positive organisms

Question 2

2 consequences of C1 deficiency

Answer 2

Increased susceptibility to infection with encapsulated bacteria
Predisposes to SLE

Question 3

C3 deficiency predisposes to

Answer 3

Recurrent infections with encapsulated bacteria

Question 4

C5-9 deficiency leads to

Answer 4

Infections with N. meningitidis and N. gonorrhoeae

Question 5

Defect in type I interferon release leads to

Answer 5

Increased susceptibility to viral infections

Question 6

5 causes of pancytopenia without splenomegaly

Answer 6

Aplastic anemia
Vit B12 deficiency anemia
Folic acid deficiency anemia
Acute leukemias
Certain forms of myelodysplastic syndrome

Question 7

Primary thrombotic microangiopathy syndromes

Answer 7

Platelet activation + diffuse microthrombosis in arterioles/capillaries
Hemolytic anemia w/ schistocytes
Thrombocytopenia
Organ injury (brain, kidney, heart)

Question 8

Pentad of Thrombocytopenic thrombotic purpura

Answer 8

Fever
Neuro symptoms (progr lethargy)
Renal failure
Anemia
Thrombocytopenia
In the setting of GI illness + normal TP, aPTT, BT

Question 9

Vinca alkaloids

Answer 9

Act on M phase of cell cycle

Neurotoxicity (peripheral neuropathy)

Question 10

Sickle cell anemia

Answer 10

Point mutation: glutamic acid instead of valine (in beta-chain of Hb)
Exertional dyspnea
Pneumonia w/ life-threatening acute chest syndrome
Recurrent abdo pain

Question 11

Heparin-induced thrombocytopenia

Answer 11

HIT treated w/ direct thrombin inhibitors (argatroban)

Avoid HMWH + LMWH

Question 12

Chronic myeloproliferative disorders

Answer 12

Mutation in JAK2 (cytoplasmic tyrosine kinase)

Persistent activation of signal transducers + activators of transcription (STAT) proteins

Question 13

Side effects of Dapsone (prophylactic ttt of HIV+ for pneumocystic jiroveci pneumonia in case of TMP-SMX allergy)

Answer 13

Fever, rash, methemoglobinemia, oxidative stress

If G6PD deficiency, hemolytic anemia

Question 14

Immunophenotyping of lymphoblasts in precursors B-ALL and T-ALL

Answer 14

B-ALL: TdT+, CD10+, CD19+

T-ALL: TdT+, CD1a+, CD2, CD3, CD4, CD5, CD7, CD8

Question 15

Intravascular hemolytic anemia

Answer 15

Decreased serum haptoglobin
Increased LDH
Increased indirect bilirubin

Question 16

Cause of Polycythemia vera

Answer 16

Majority have JAK2 V617F mutation

Hematopoietic stem cells more sensitive to growth factors

Question 17

Labo in HUS

Answer 17

Decreased hemoglobin, platelets

Increased bleeding time, lactate dehydrogenase, bilirubin, BUN, creatinine

Question 18

Activating mutation of KRAS gene

Answer 18

Constitutive activation of EGFR
Increased cell prolif + growth
Resistant to chemotherapy w/ anti-EGFR drugs (cetuximab, panitumumab)

Question 19

Labo in lead poisoning

Answer 19

Microcytic anemia w/ normal iron studies

Basophilic stippling

Question 20

Serious complication of chronic hemolytic anemia + frequent blood transfusion

Answer 20

Hemosiderosis

Hemosiderin (brown-yellowish pigments) in Kupffer cells in liver

Question 21

After various anticancer agents, tumor cells can become resistant

Answer 21

Human multidrug resistance (MDR1) gene
P-glycoprotein: transmembrane ATP-dep efflux pump protein
P-GP: reduce influx of drugs into cytosol, increase efflux from cytosol
So prevent action of CT

Question 22

Growth factors for angiogenesis in neoplastic + granulation tissue

Answer 22

VEGF and FGF
Proinfl cytokines (IL1, IFN-G) indirectly by increased VEGF
Laminin in basement membranes: barrier to new Vx formation

Question 23

Chronic vs acute leukemias on peripheral blood smears

Answer 23

Chronic: prevalence of mature cells
Acute: prevalence of blasts

Question 24

Protein C deficiency

Answer 24

Exaggerate hypercoagulability after Warfarin: short 1/2 life of prot C + def of prot C
Thrombotic occlusion of microvasculature w/ skin necrosis

Question 25

Hairy cell leukemia

Answer 25

Indolent B-cell neoplasm Bone marrow failure Infiltration in reticuloendoth system: massive splenomegaly Dry tap of BM + lymphocytes w/ cytoplasmic projections

Question 26

Splenic changes in sickle cell ds

Answer 26

Repeated splenic infarctions Then splenic atrophy + fibrosis (late ado): autosplenectomy Then inf w/ encaps bact

Question 27

Megaloblastic anemia

Answer 27

``` Severe macrocytosis (MCV > 110) Folic acid or vit B12 def Chronic hemolytic anemia: increased erythrocyte turnover so increased folic acid requirements; risk of macrocytosis ```

Question 28

Aplastic anemia

Answer 28

Triad: low Hb, thrombocytopenia, absent hematopoietic cells in BM Increased circulating EPO if normal renal fct

Question 29

Pure red cell aplasia

Answer 29

Rare form of marrow failure Severe hypoplasia of marrow erythroid elements Normal granulopoiesis + thrombopoiesis Ass w/ thymoma, lymphocytic leukemias, parvo B19 inf

Question 30

DIC

Answer 30

Complication of G- bact sepsis, acute pancreatitis, burn injury, APL G- bact endotoxins activate coag cascade Schistocytes, thrombocytopenia Decreased fibrinogen, prolonged PT + PTT

Question 31

AML, M3 presentation

Answer 31

Can present w/ persistent inf + coagulopathy: hgic signs BM biopsy: promyelocytes w/ Auer rods t(15;17) translocation: fusion of retinoic acid receptor-alpha gene + promyelocyte leukemia gene

Question 32

Follicular lymphoma

Answer 32

Overexpression of bcl-2 | Increased secretion of Bcl-2 prot: inhibits apoptosis

Question 33

Infections in sickle cell ds

Answer 33

Strepto pneumoniae Hemophilus influenza Osteomyelitis: #1 Salmonella, #2 Staph aureus and E coli

Question 34

Sickle cell trait

Answer 34

Asymptomatic Relative protection from malaria Normal Hb, reticulocyte, RBC index values Life expectancy = gen pop

Question 35

B-cell vs T-cell ALL

Answer 35

B-cell: 70-80%, fever, malaise, bleeding, bone pain, HSM | T-cell: 15-17%, mediastinal mass, resp sympt, dysphagia, SVC sd

Question 36

Ttt of hereditary spherocytosis

Answer 36

Splenectomy + blood transfusions | Folic acid supplementation

Question 37

Hemophilia

Answer 37

Low fact VIII or IX: failure to convert prothrombin to thrombin Adding thrombin to blood: clotting