Heme Flashcards
Peutz-Jeghers syndrome has what features? What is management?
Autsomal dominant unregulated tissue growth (particularly GI)
Hyperpigmented mucocutaneous macules (lips, buccal mucosa, palms/soles)
Hamartomatous polyps in GI tract –> occult bleeding or intestinal obstruction
Increased risk for GI, breast, genital tract cancers
Management: Annual anemia screening, cancer screening (eg upper/lower endoscopy)
Desmopressin can be used for what coagulopathy?
von Willebrand disease
Anti-D Ig can be first-line therapy for what coagulopathy?
ITP - only works if they are Rh(D)+ and Coombs-negative
Who is more likely to develop chronic ITP (lasts >1 year) rather than <3 months self-resolved? What is appropriate testing and management?
Those with mild initial presentation and no preceding viral trigger
Bone marrow exam and blood tests for infection and autoimmune disease; if negative, management similar to ITP
What is first-line therapy for ITP?
Children: Glucocorticoids, IVIG, or anti-D if bleeding; otherwise observe if cutaneous only (platelet cutoff of 30,000 applies to adults only)
What is second-line therapy for chronic ITP?
Rituximab
Thrombopoietin receptor agonists
Splenectomy if refractory
Treatments for hereditary spherocytosis
Folic acid supplementation
Blood transfusion
Splenectomy
What tests are used to confirm hereditary spherocytosis?
Acidified glycerol lysis (osmotic fragility)
Eosin-5-maleimide binding tests
Why can polycythemia of newborn cause?
Respiratory distress, cyanosis, apnea
Irritabiliy, jitteriness
Hypoglycemia, hypocalcemia - due to increased cellular uptake
Name the Hemoglobin of these diseases:
Normal
Beta-thalassemia minor
Beta-thalassemia major
Sickle cell trait
Sickle cell disease
Normal: Hgb A (2 alpha 2 beta)
Beta-thalassemia minor: Increased Hgb A2 (2 alpha 2 delta), decreased Hgb A
Beta-thalassemia major: Vastly increased Hgb A2, F; absent Hgb A
Sickle cell trait: Increased Hgb S, vastly decreased Hgb A
Sickle cell disease: Vastly increased Hgb S, F; absent Hgb A
What is a skeletal consequence of untreated beta thalassemia major?
Skeletal abnormalities due to extramedullary hematopoiesis
What is a complication of beta thalassemia major treatment?
Blood transfusion-dependent iron overload - use chelation therapy to avoid damage to liver, kidneys, and endocrine glands
What causes the destruction of cartilage and bone in hemophilic arthropathy?
Hemosiderin deposition –> synovial inflammation –> fibrosis and destruction
Best seen on MRI but may be visible on x-ray if severe
What is the mechanism of G6PD deficiency RBC death?
Lack of NADPH –> lack of glutathione –> oxidation –> denature/precipitate Hgb into Heinz bodies –> reduced RBC flexibility –> cell damage (bite cells) and lysis in reticuloendothelial system
What is the mechanism of penicillin and cephalosporin-induced immune-mediated hemolytic anemia?
Bind to RBC surface and act as hapten for IgG attachment –> RBC destruction by splenic macrophages –> extravascular hemolysis
What virus can cause aplastic crisis of RBCs in those predisposed to RBC lysis (hereditary spherocytosis, sickle cell disease, etc.)?
Parvovirus
Sickle cell trait has what most common renal issue? What are less common renal and non-renal issues?
Microscopic/gross hematuria from sickling in renal medulla
Hyposthenuria - impairment in concentrating ability - nocturia and polyuria
Less common:
UTI, particularly during pregnancy
Splenic infarction at high altitudes
Hereditary spherocytosis is more common in what population?
Northern European, autosomal dominant
What is paroxysmal nocturnal hemoglobinuria? Manifestations?
Acquired, complement-mediated hemolytic anemia
Hemolytic anemia
Cytopenias
Hypercoagulability
Diagnosed by CD55 and CD59 absence
What does dactylitis in an infant suggest?
Vaso-occlusive crisis in sickle cell disease
Also has erythema and warmth, may be preceded by trigger (eg dehydration)
+/- low-grade fever
Older patients should be considered for autoimmune disorders (eg psoriatic arthritis, ankylosing spondylitis)
Sickle cell predisposes to what bacterial osteomyelitis?
Salmonella
S aureus is most common cause in all patients
Hemoglobin < what is concerning for pathologic etiology in infant?
<9; remember that physiologic anemia of infancy can present with nadir around 11 at age 2-3 months in term infants
How do TTP and ITP treatments differ?
TTP: Plasma exchange (removes anti-ADAMTS13 Ab and replaces ADAMTS13)
ITP: IVIG
Heinz bodies of G6PD deficiency appear on what stain?
Special crystal violet stain (not Wright stain)
