Heme- UWORLD Flashcards
94- Q1. What class of Ig is Anti-D antibody? Explain the principle of injecting RhoGAM to prevent erythroblastosis fetalis
IgG
First Rh+ fetus may produce Anti-D IgG in Rh- mom, and for second Rh+ fetus this antibody can CROSS PLACENTA and attack fetus RBC. By injecting RhoGAM during third trimester, it sqeusters fetal D antigen, preventing synthesis of Anti-D IgG in mom
- Don’t have to worry about erythroblastosis fetalis for ABO because it is IgM, which is too big to cross placenta
94- Q 9. Signs of sepsis (low BP, systemic infection signs). What hematologic condition should I think first?
DIC
Shistocytes: RBC gets sheared by thrombi.
- In fact, ONLY ONE abnormal RBC form on blood smear in DIC is shistocytes, no others are noticed in DIC
- sepsis is S in STOP Making Thrombi
95- Q 1. What is pathophysiology of DIC in obstetrics?
placenta damage -> release of tissue factor (enriched in placental trophoblast) -> initiation of extrinsic coagulation cascade
- obstetrics is O in STOP Making New Thrombi
95- Q 5. mucosal bleeding, which is platelet defect, can be seen in both ITP and von-willebrand disease. What would patient’s history differ between these two?
- ITP: associated with viral illness, NOT chronic
- von-willebrand disease: decreased vWF, chronic
=> pt may present history of epistaxis even in childhood
95- Q 25. Hepcidin is released from where?
liver
95- Q 30. erythroblastosis fetalis vs. hydrops fetalis: they both present similarly ( immediate death, generalized edema, hepatosplenomegaly). What lab test can differentiate these two?
coombs test
- eryrthroblastosis fetalis: positive direct coombs test (maternal anti-D IgM )
- hydrops fetalis: negative coombs test, no antibody mediated RBC destruction. Barts Hb (gamma4) is just not compatible with life.
95- Q 35. JAK2 mutation is associated with myeloproliferative disorders. What is JAK2
CYTOPLASMIC NON-RECEPTOR tyrosine kinase
- EPO has its own receptor
- EPO binds to EPO receptor -> cytoplasmic JAK2-STAT binds to ligand bound EPO receptor, stimulating erythropoeisis
96- Q 28. Aplastic crisis vs. Aplastic anemia: what is major difference?
aplastic crisis: primarily affecting RBC ONLY. Occurs after parvovirus B19 (naked single stranded DNA)
aplastic anemia: bone marrow issue. Affects all lineages- RBC, platelet, WBC
*aplastic anemia is mismonomer
97- Q 10. smaller and fewer platelets on blood smear, itchy red rash. DIagnosis?
Wiskott-Aldrich syndrome
WA
Thrombocytopenia
Eczema (atopic dermatitis)
Recurrent infection
*buzzword: smaller and fewer platelets on blood smear
97- Q 20. 3 week yo baby. Intracranial hemorrhage with signs of increased ICP (abnormal gaze, bulging head). No apparent signs of trauma. Diagnosis?
neonatal vitamin K deficiency
- > vitamin K is synthesized by gut flora (also folate), neonates take time to develop gut flora. Also, vitamin K is not in breast milk as well.
- tx is intramuscular vitamin K injection
98- Q 7. What is normal liver span?
6-15 cm
98- Q 7. Where is major site of platelet squestration?
spleen
- so does RBC
98 - Q 8. Through what surface molecule does cancer cells evade immune destruction by CD8 T cell?
PD-1 Ligand (programmed death)
- PD-1 ligand in cancer cells binds to PD-1 receptor on CD8 T cells, inhibiting CD8 T cell and evade cell mediated cytotoxicity. Targeting PD-1 by drug thus can be used as anti-cancer agent
98- Q 13. MOA of Bortezomib, proteosome inhibitor, in treating multiple myeloma?
Bortezomib is a proteosome inhibitor, resulting in accumulation of damaged/cytotoxic/misfolded proteins within plasma cells, leading to APOPTOSIS
- this drug is NOT in FA
98 -Q25. How does kidney releases EPO?
peritubular cells in RENAL CORTEX sense O2 sense hypoxia