hematology Flashcards
hgb v age
high at birth. physiologic nadir at 2-3mo. adult lvl at puberty
retic count
high in anemia. low if BM failure or diminished hematopoiesis
microcytic
Fe def, thalassema, sideroblastic anemia, lead, chronic disease
macrocytic anemia
B12, folate, thiamine
normocytic
high retic: hemangioma, DIC, hemolytic anemia, SCD, blood loss
low retake: red cell aplasia, malig, falcon anemia
Fe def
most common blood disease of infancy and childhood. most cause by inadequate intake. Fe store deplete by 6-9mo so sx start 9-24mo. occult blood loss
P: spoon shaped nails, diminished attension and ability to learn
thalassemia
defective sun of Hgb chain. major hg is hgA1= 2 alpha + 2 beta
hemolysis –> incr BM activity –> BM enlarge –> incr size of bone in face skull etc
alpha thalassemia
southeast asians. 4 alpha globin gene per diploid cell.
1) silent carrier- 1 deleted. no anemia, asx
2) alpha T minor: 2 delted. mild anemia
3) Hgb H disease: 3 delated. severe anema at birth. elevated Hgb Bart’s (bind O2 strongly and doesn’t release), lifelong severe anemia
4) fetal hydrops- 4. death
beta thalassemia major
2 beta gene in each cell. mediterranean. cooler’s anemia - total absence of beta global chain or def production. profound hemolytic anemia + hepatosplenomegaly and BM hyperplasia = thalassemia facies. deal growth and puberty. labs- severe hypochromia and microcytosis, target cell, poikilocytes, incr uncongugated bili, LDH, serum Fe, low or absent HgbA and elevated Hgb F. tx with lifelong transfusions
C: hemachromatosis due to incr Fe absorption from intestine and from transfusion.
beta thalssemia minor
mild asx anemia with hub 2-3g/dl below norm. hypo chromic, microcytosis, target cell, anisocytosis= vary size. no tx. Fe is normal or elevated so need to dd Fe def anemia.
sideroblastic anemia
ring sideroblast in BM.
folic acid def
anemia sx + FTT, chronic diarrhea, irritability. dx low serum folic acid. tx- diet with folic acid
B12 def
combine with intrinsic factor secreted by gastric parietal cells absorb in terminal ileum bad diet (vegan), no IF (juvenile pernicious anemia) can't absorb (crohn). P: sx of anemia + smooth red tongue, neuro ataxia, hyporeflexia, pos babinski.
hereditary spherocytosis lead to
pigmented gallstone, aplastic crises associated with parvovirus 19
glycolytic enzymatic defects of RBC
pyruvate kinase def and glucose 6 phosphate deH def
pyruvate kinase def
AR. decr production of PK isoenzyme. ATP depletion. incr RBC survival.
P: pallor, j, splenomegaly, kernicterus in neonates. polychromic RBC on smear. dx by decr PK activity in RBC.
tx: transfusion and splenectomy
AI hemolytic anemia
primary AIHA- idiopathic. secondary is underlying disease process like lymphoma, SLE
dx: direct coombs test is positive.
tx: transfusion- transient benefit, corticosteroids
G6PD def
critical for protecting RBC from ox stress. trigger of hemolysis include infection, fav beans, drugs
P: sx for 1-2d after exposure to oxidant. hemolysis –> abd pain, V/D, fever, hemogloninuria, jaundice, hsm
lab: hemoglobinuria, incr retic, smear show bite cells and heights, heinz bodies
dx: low G6PD in RBC
tx: transfusion. no splenectomy
alloimmune hemolytic anemia
newborn Rh and ABO hemolytic disease.
1) mom is Rh neg= has Rh ab. baby Rh pos so attacked. hydrops, J direct comb positive
2) ABO hemolytic disease: O mom v baby AB, A,B. weakly pos direct coomb test. can occur in first preg unlike Rh. light tx
microangiopathic hemolytic anemia
mechanical damage to RBC due to passing through injured vascular endothelium. et- severe HTN, artificial heart valve, hemangioma, DIC.
P: anemia+ thrombocytopenia
sickle cell
stacking when low O or acidosis
dx: hgb electrophoresis
crises: vasooclussive crises, bone crises, acute abdominal crises usually in mesenteric A, stroke, priapism, acute chest syndrome, sequestration crises, aplastic crisis (dec RBC production after parvovirus 19- decr retake and hgb) hyper hemolytic crisis (decr hub, incr retic and bili)
SCD labs
rbi life span -10-50d
hg- 6-9, hct- 18-27, WBC 12-20, plt incr, bili incr, sicle cell, target cell, howel jolly bodies n smear. bone marrow erythroid hyperplasia
SCD die
most from infection - 30% sepsis or meningitis in 1st 5y. so fever in SCD pt need complete workup. osteomyelitis can mimic bone crises.
salmonella infection common
scd preventative care
1) hydroxyurea - chemotherapy that incr Hgb F - decr vasooclusive crisis.
2) daily oral penicillin prophylaxis in first mo to def s pneumonia infection
3) daily folic acid
4) routine immunizations
5) serial transcranial doppler US or MRA.
pancytopenia
congenital aplastic anemia- fanconi anemia
acqruired aplastic anemia- drugs, infection, chemical, rad. idiopathic.
sx: bruising, petechiae, pallor, serious infection due to neutropenia. see hypocellualr BM.
fanconi anemia
- AR. onset of 7yo with ecchymosis and petechiae. skeletal abd - short, absence of hypoplasia of thumb and radius, skin hyper pig, renal abn
lab: decr hgb retic, plt,. incr hgb F. tx by RBC transfusion, corticosteroid, BM transplant
parvovirus 19
not sx. associated URI s and facial rash- slapped cheeks. decr retic and hgb. normal plot
spontaneous recovery in 2wk
TEC
possible postviral AI. anemia after 1yo, slow onset, sx of anemia. decr hgb and retic. normal plot. no tx. spontaneous recovery
polycythemias
incr in RBC relative to total blood V. hct>60%. primary polycythemia is rare, malig.
secondary polycythemia due to incr erythropoietin production that could be appropriate (chronic hypoxemia 2/2 CHF or pul disease, high altitude) or inappropriate (being malig tumor)
P: ruddy red facial complexion with normal liver and spleen
lab: incr Hct and hgb. normal plot and wbc, EPO high
tx: ID etio. phlebotomy
C: thrombosis, bleeding
F 8 D
include hemophilia A: defect in VIII. plt is normal. and vWb D.
factor 8 or 9 def
prolong aPTT, normal PT, normal bleeding time/plt. no petechiae. has hemarthroses.
vWb D
plt activity is defective bc of decr in vWf needed for plt to adhere to vessel wall.
AD. type I is mild quantitive def in F8 and wWf. II: qualitative. III- absent vWf=worst
P: epistaxis, menorrhagia, bruising,
prolong pTT, bleeding time. normal PT/plt. no petechiae, rare hemarthroses
tx: DDAVP induce vWf release from endothelial cells - use of prophylaxis bf surgery. cryoprecipitate has vWf
thrombocytopenia
normal PTT, PT. prolong bleeding tim. low plt. petechiae. no hemarthroses
plot function defect
normal PTT, PT, plt. prolong bleeding time. petechiae. no hemarthroses
vit K def
F2,7,9,10, S,C. etio- diarrhea, pancreatic insuf biliary obstruction decr absorbtion. hemorrhage disease of newborn. 24hr after birth- present with cutaneous bleeding, hematemesis, from circumcision site, umbilical cord.
prolong PTT, PT. normal bleeding time/plt. petechiae and hemarthrosis
tx: prevent with IM it K. FFP for severe
DIC
accelerated fibrinogenesis and fibrinolysis. consume procoag factors and result in hemorrhage.
Occur 2/2 to local factors (large hemangioma) or systemic (sepsis, hypothermia, malig, heat stroke).
prolong PTT, PT, bleeding time. low plot. petechiae. sometimes hemarthroses
tx: tx underlying cuase. transfuse fibrinogen, FFP, plt. heparin if underlying defect can’t be corrected
hemaphilia A
deep soft tissue bleeding and hemarthrosi are hallmarks
severe- spontaneous pleeding 5%.
C: CNS bleeding is worst
tx: DDAVP desmopressin acetate stimulate release of stored F8
decr plt production
congenital- wiskott aldrich (thrombocyotpenia , usually small plt, eczema), thrombocytopenia absent radius syndrome (TAR):
incr plt destruction
immune mediated: ITP, neonatal immune mediated thrombocytopenia
drug, DIC, enlarge spleen
hemolytic uremic syndrom
large hemangioma sequester and destroy plt- kasabach merritt syndrome.
Immune thrombocytopenic purpura (ITP)
viral, drug induced, idiopathic =most common.
viral infection –> 1-4wks later, ab that cross react with plt
P: cutaneous bleeding, petechiae, mucous mem bleeding (epistaxis, gum), internal bleeding is rare.
lab- sticky plt.
tx: supportive,IVIG if active bleeding, corticosteroid. antiD ig is second line.
prog: 80% self resolve in mo. chronic if >6mo–> splenctomy
neonatal immune mediated thrombocytopenia
1) passive AI thrombocytopenia (mom has ITP, ab cross placenta and kill fetal plt. mom has thrombocytopenia
2) isoimmune thrombocytopenia: mom make ab agianst fetal plt due to sensitatization of ag her own plt lack. mom’s plt count is nl
hypercoag
def of protein C, S or antithrombin III or must in factor V
protein C def
most potent anticoag protein.
homozygote = no C= purpura fulminans- non thrombocytopenia purpura- fever, shock, rapidly spreading skin bleeding and IV thrombosis
hertozygote- present later with DVT or CS thrombosis
dx- test for C
tx: heparin, FFP, warfarin, purified C
protein S, aT III, F V leiden def present the sam way. specific test for lvl and function of each factor is diagnostic
neutropenia classify
risk of infection is directly related to ANC
mild- 1000-15000
mod-500-1000: infect mucous me and skin, cellulitis, gingivitis, stomatitis
severe
neutropenia etio
in kids, infection is most common. HIV, EBC, CMV, hep A/B. bacteria (rocky mouton, typhus), malaria all suppress BM, marginate neutrophil or exhaust receive.
chronic benign neutropenia of childhood
severe congenital agranulocytosis= kostmann syndrome
AR. ANC
cyclic neutropenia
fever, oral ulcer stomatitis in periods. cycles last on av of 21d. dx by cyclic nature of neutropenia- serial neutrophil counts
