First Pass Miss Flashcards
What is the lifespan of an average neutrophil, platelet, or RBC? How long does it take to make an RBC in the bone marrow?
Neutrophil - 6-8 hours
Platelet - 7-10 days
RBC - 120 days, produced in about 7 days
Where does hematopoesis first begin and where does it ultimately move to / when?
Starts in yolk sac, then liver / spleen, before finally moving to bone marrow
Moves to primarily bone marrow / some lymph nodes by birth
What causes basophilic stippling in RBCs?
Aggregation of residual ribosomes and RNA, seen in sideroblastic anemia, lead poisoning, etc
What are myeloid precursors called, where should they be found, and what CD markers are they positive for?
Myeloblasts, present in small amounts in bone marrow (should NOT be in blood)
Positive for CD34 and CD117
-> note, CD34 will be negative in APML because it is past the stem cell stage
What are some causes of neutrophil defects in chemotaxis?
Congenital - LAD1
Acquired - corticosteroid therapy (downregulates P-selectin), myelodysplastic syndromes
What is Hand-Schuller-Christian disease and what is it associated with?
Langerhan’s cell histocytosis seen in age >2 (greater than 2 names)
-> scalp rash, skull defects, exophthalmos, and diabetes insipidus (due to posterior pituitary involvement)
What is hemophagocytic syndrome? Symptoms?
Usually an acquired disease where histiocytes in bone marrow ingest RBCs, white cells, and/or platelets
Due to infection or cancer
Symptoms: pancytopenia, hepatosplenomegaly, fever, multi-organ dysfunction
What is Rosai-Dorfman disease?
Sinus Histiocytosis with Massive Lymphadenopathy
- > Marked expansion of lymph node sinuses causng a lymphadenopathy
- > chronic, cervical lymphadenopathy of unknown cause
What are the three forms of Gaucher’s disease? What disease is it associated with?
- Chronic, adult-type with no CNS involvement (most common)
- Acute, infantile type - CNS involvement but not bone involvement
- Subacute with CNS and bone, adolescent onset, better prognosis
Associated with multiple myeloma
In what states will you see target cells and why?
Target cells caused by too much cytoskeleton which is normally removed by spleen and liver to not be removed.
Can be seen in asplenia or liver disease
Also seen in iron deficiency -> overproduction of hypochromic, microcytic RBCs which do not have time to be properly filtered by spleen
When is G-CSF used?
To produce a rise in circulating neutrophils:
- Post-chemotherapy, radiotherapy, or stem-cell transplant to shorten neutropenia
- Severe neutropenia (congenital or acquired)
What problems can cause deficiencies in neutrophil chemotaxis?
- LAD-1 - integrin problem (CD18)
- Corticosteroid use - downregulates P-selection
- Myelodysplastic syndromes
What is the definition of anemia for men / women?
Decrease in hemoglobin in the blood
Men: Hgb < 13 g/dL or <40% hematocrit
Women: HgB <12 g/dL or <36% hematocrit
Hct is typically 3x the Hgb
What is the DDx of normocytic anemias?
Anemia of chronic disease - most common, can also be microcytic Chronic kidney disease - loss of EPO Blood loss Hemolysis Mixed etiologies, i.e. genetic Bone marrow disease
What is polychromasia and in what causes of anemia does it happen? What count is indicative of increased RBC turnover?
Increased reticulocytes (100,000 = absolute count showing increased turnover) on blood smear (stain blue due to residual DNA in cytoplasm, and are larger than normal RBC)
Happens in anemia due to acute blood loss or hemolysis -> more erythropoesis
What are some other important studies in the workup of anemia?
- Hemoglobin trend
- Creatinine - chronic kidney disease can cause anemia
- Iron studies - microcytic
- Hemolytic workup - reticulocyte count, LDH, bilirubin, haptoglobin
- Liver function tests - if macrocytic
- TSH - if macrocytic
What are the major storage and carrier proteins for iron?
Storage - ferritin, within reticuloendothelial cystem
Carrier - Transferrin - delivers iron to macrophages in RES and developing erythrocytes in bone marrow via transferrin receptor
What are the congenital and acquired causes of sideroblastic anemia?
Congenital - ALA synthase mutation
Acquired:
1. Alcohol - mitochondrial poison
2. Lead - inhibits ALA dehydratase and ferrochelatase
3. B6 deficiency - usually due to isoniazid therapy
4. myelodysplastic syndromes
What are more specific signs and symptoms for iron deficiency anemia (IDA)?
Pica - wanting to eat ice, baking power, clay, chalk
Restless legs - remember, iron is used to make dopamine and low levels (Ferritin <50) can cause RLS
Koilonychia - spooning of the nails - very severe cases, most specific
Why might a patient be refractory to ferrous sulfate / how long should they take to improve?
RBCs start increased in 4-7 days, resolution of anemia within 4-6 weeks depending on deficiency
Refractory reasons: Noncompliance Wrong diagnosis (more than one) Not enough iron - excessive bleeding Malabsorption
What is the cause of Classic hereditary hemochromatosis? What chromosome? Is it common?
Autosomal recessive HFE gene mutation on chromosome 6
-> increased intestinal absorption of iron, decreased hepcidin production, increased ferroportin transport
Most common inherited single-gene disease in US
Where does iron tend to accumulate in hereditary hemochromatosis?
Liver, pancreas, skin, heart, pituitary, and joints
What are the hepatic manifestions of HH?
Hepatomegaly, fibrosis and cirrhosis, with common progression to hepatocellular carcinoma (most common cause of death)
Causes restrictive -> dilated cardiomyopathy in heart
What is the classic triad of HH?
BCD
Bronzing of the skin - hyperpigmentation
Cirrhosis
Diabetes (due to pancreatic insufficiency)