Path- RBC Path Hertz Flashcards
Etiology of chronic blood loss
iron loss GI causes (neoplasm) gynecologic causes (menstruation)
hereditary spherocytosis: etiology
autosomal mutation of spectrin, band 3 or 4.2, and ankyrin
hereditary spherocytosis: morphology
spherocytes
Howell-Jolly body (small dark nuclear remnants)
anisocytosis (unequal-sized RBC’s)
hereditary spherocytosis: presentation
anemia splenomegaly cholelithiasis jaundice elevated MCHC
hereditary spherocytosis: complications
aplastic crises (parvovirus B19) hemolytic crises (infectious mono) gallstones (pigment stones
hereditary spherocytosis: diagnosis
osmotic fragility test
hereditary spherocytosis: treatment
splenectomy
Conditions protective against malaria
G6PD deficiency
Thalassemia
Sickle cell disease
G6PD deficiency: etiology
X-linked gene mutation in G6PD. causes GSH problems leading to oxidative injury and hemolytic anemia
G6PD deficiency: pathogenesis
asymptomatic unless exposed to one of the following:
drugs (antimalarials, sulfonamide, large dose ASA, Vit K derivates)
infections
fava beans
G6PD deficiency: intravascular or extravascular hemolysis?
both!
G6PD deficiency: morphology
heinz bodies (RBC intracellular inclusions of denatured oxidized, precipitated HB) bite cells
G6PD deficiency: presentation
anemia
hemoglobinemia
hemoglobinuria 2-3 days post exposure
G6PD deficiency: diagnosis
colorimetric testing
molecular analysis
repeat studies ~1 month later to allow time for regeneration
G6PD deficiency: complications
G6PD Mediterranean variant = more severe hemolysis
Sickle cell disease: epidemiology
most common familial hemolytic anemia in the world
most common hemoglobinopathy
Sickle cell disease: etiology
autosomal recessive beta-globin gene point mutation creating HbS. deoxygenation results in formation of long polymers that aggregate. it can be reversible with oxygen, but chronic damage can lead to irreversibly sickled cells
Sickle cell disease: major pathologic manifestations
chronic hemolysis
microvascular occlusions
tissue damage
Sickle cell disease: morphology
sickle cells=]
target cells
spherocytes
reticulocytes
Sickle cell disease: presentation
splenomegaly in children autosplenectomy in adults vascular congestion thrombosis infarction of bones, liver, kidneys, retina, brain, lung, skin hemosiderosis gallstones prominent cheek bones hyperbilirubinemia impaired growth in children hypostheuria (can't concentrate urine)
Sickle cell disease: diagnosis
Sickledex
Hb electrophoresis
X ray: crewcut
extramedullary hemaopoiesis
Sickle cell disease: complications
chronic hemolytic anemia microvascular obstruction --> vaso-occlusive pain crises acute chest syndrome aplastic crises (parvo B19) infection-prone hand-foot syndrome (dactylics) splenic sequestration crises
Sickle cell disease: treatment
PCN prophylaxis against pneumococcus and haemophilu
hydroxyurea (increases HbF and has an anti-inflammatory effect d/t WBC inhibition)
Sickle cell disease: factors affecting rate/degree of sickling
- [HbS]
- MCHC
- Intracellular pH
- RBC transit time
