Heme/onc Flashcards
Bone marrow becomes primary site of hematopoiesis after ____ weeks
22 weeks GA;
Secondary yolk sac: 2.5-10 weeks
Fetal liver: 6-22 weeks
Neonatal Autoimmune thrombocytopenia (ITP, lupus, autoimmune dz) vs neonatal alloimmune thrombocytopenia
Autoimmune: maternal anti-platelet antibodies destroy mom’s platelets, cross placenta, destroy baby platelets
Alloimmune = women with normal platelet counts
Kasabech-Merrit syndrome
multiple skin lesions that resemble hemangiomas, or a single, large rapidly growing hemangioma. Can also have retroperitoneal or mediastinal vascular abnormalities without displaying dermatologic lesion. High output cardiac failure, DIC, thrombocytopenia
Maternal diabetes = ____ RBC production
Increased RBC production associated with fetal hyperinsulinemia, tissue hypoxia, increased EPO
Polycythemia leads to thrombo______; what are other sequelae
cytoPENIA. More sluggish circulation
Neuro: lethargy, irritable, apnea, seizure
Resp: hypoxia, increased WOB
Hypoglycemia (unknown mech)
Hyplcalcemia (elevated calcitonin gene related peptide)
Thrombocytopenia - platelet consumption where resistance to blood flow is highest
Exchange transfusion equation
[Patient Hct - Desired Hct]/Patient Hct x infant’s blood volume
Most common hemoglobin abnormality in world, clinical presentation
Hemoglobin E; asymptomatic, mild microcytic anemia, or severe transfusion-dependent anemia
What enzyme deficiency is prevalent among Amish, Mediterranean/AfricanAsian?
amish = pyruvate kinase deficiency, G6PD for the others
What disease is due to chromosomal fragility and breakage?
Fanconi’s anemia (congenital aplastic anemia). No hemolysis or reticulocytosis
What is defect in hereditary spherocytosis
defects in membrane proteins
Ankyrin, spectrin
Genetic mutation in sickle cell disease?
Valine for glutamic acid substitution at position 6 of beta-globin gene
Effect of gestational thrombocytopenia on fetus?
Isolated thrombocytopenia in pregnant women of unknown etiology; does not impact fetus or infant and resolves post partum
Timeline of hemorrhagic disease of newborn
Early onset: 24 hrs - placental transferred drugs that inhibit Vit K production (anticonvulsants, cephalosporin antibiotics, warfarin)
Classic: 2-7 days of life, bleeding from stump, GI bleeding, ICH, prolonged bleeding after invasive procedures (poor stores and intake)
Late onset: 2 weeks-6 months; poor intake of Vit of vit K or liver dz
All respond to vitamin K
Treatment of transient myeloproliferative disease with chemo does or does not help reduce risk of future cancer?
NO
Sacroccygeal teratomas
benign germ cell tumors composed of all three embryonic layers. Mature or immature (high malignant). Sporadically occur. Can cause high output HF, non-immune hydrops, consumptive coagulopathy and thrombocytopenia. Can involve dura of spinal cord, cause Neuro symptoms. Tx = complete surgical excision, including coccyx to prevent recurrence.
Recurrence risk is 10%. Risk of malignant transformation is 15-20%
What is ligandin?
helps liver take bilirubin from plasma
Fetus makes EPO in _____
liver (less sensitive to hypoxia compared to kidneys)
Physiologic nadir is _____ weeks. Preterm is more ____. Production of EPO is regulated by ______
8-12 weeks. Preterm is earlier, more severe, requires transfusion. Production of EPO is regulated by transcription factor HIF-1
DCC increases RBC volume by _______
10-15%
most iron transfer to fetus occurs after ____ GA
30 weeks GA. Corresponds with peak efficiency of maternal iron absorption
Prenatally, fetal iron accumulates at ____ mg/kg daily
1.6-2 mg/kg daily
Healthy term infant’s total body iron content is ____ mg/kg body weight, ____% of which is in Hgb
75 mg/kg body weight, 80% in hemoglobin
Beckwith Wiedemann, inheritance, mutation, clinical features
autosomal dominant, 11p15.5, macrosomia, large tongue, omphalocele, hypoglycemia –> increased intra-abdominal malignancies (Wilms tumor, hepatoblastoma), but NOT leukemia
Factor 8/9 deficiency are _____ while 11 and 13 are _____
X-linked recessive, autosomal recessive
VWD is AD or AR
Megakaryocytes only account for 0.03-0.1% of nucleated cells in BM - detected in fetal liver and circulatory system as early as _____ weeks in gestation
8 weeks; usually SMALLER, lower than adult megakaryocytic, but greater #
Greater mechanisms of TAR
blockage in differentiation of an early megakaryocytic precursor resulting in decreased platelet production (TPO, TPO-R are normal)
Facts about neuroblastoma
Children with less than 12 mo with advanced metastatic dz = favorable prognosis, adrenal site is most common primary site, derived from primitive empathetic ganglion cells. Central hypoventilation, HD, NF-1 asssociated
Wilms tumor syndromes?
WAGR, Denys-Dash (progressive renal dz, male pseudohermaphroditism), Perlman syndrome (fetal gigantism, visceromegaly, abnormal facies, b/l renal hamartomas), beckwith wiedemann
Enzyme that covers heme to biliverdin
heme oxygenase
Biliverdin reductase then catalyzes conversion to bilirubin
Placenta can remove indirect bilirubin but not biliverdin
Embryonic Hgb
Embryonic Hgb predominates in first 8 weeks gestation (Gower 1, 2, and Poland)
Beta-globin synthesis begins to increase at 30 weeks gestation —> concomitant decrease in percentage of gamma-globing chain synthesis
Fetal-hemoglobin still accounts for 70-90% of neonate’s total Hgb at term GA
After birth, rapid decline in gamma-globulin, further increase in beta-globing production
By 1 year, infant hub is similar to adult. 95% Hgb A, 1-2% Hbgb F, 3-4% Hgb A2
Affinity of Hgb
Shift in curve to left - increase in hemoglobin/oxygen affinity; fetal Hgb, (lower H+/increased pH)), decreased CO2, decreased 2,3-DPG, decreased temperature
Decrease in affinity shifts the curve to the right
red blood cell storage lesion is
due to multiple changes in physicochemical nature of RBC: changes in RBC physical structure, altered RBC metabolism, depletion of NO, humoral factors (cytokines released)
Indirect Coomb’s test
Rh also has C, c, D, E, e, and G antigens. Rh test tests presence but also degree of alloimmunization
In at risk woman, need to screen in first trimester, followed by repeat screening at 28 weeks
Stages of bilirubin encephalopathy
Stage 1: infant with decreased activity, poor suck, hypotonia, slightly high-pitched cry (all these are reversible)
Stage 2: stage 1 + rigid extension of all four extremities, tight-fisted posturing of arms, crossed extension of legs, and high-pitched irritable cry, seizures, retrocollis (backward arching of neck), opisthotonos (backward arching of trunk) and fever
Stage 3: hypertonia with marked retrocollis and opisthotonos, stupor, coma, and a shrill cry
61C / D; adequate hydration is to ensure adequate urine output. Bilirubin isomer (lumirubin) is excreted in bile and urine
