Pediatric Hematology

Question 1

Consequence of Pediatric Anemia

Answer 1

decreased IQ

Question 2

Classification of Anemia -

Vit B12 and folate deficiency

(typically seen w/ poor diet)

Answer 2

macrocytic

(enlarged RBC)

Question 3

Classification of Anemia -

assoc w/ systemic illness that impairs RBC synthesis

(anemia of chronic disease)

Answer 3

normocytic

(lacking sufficient RBCs)

Question 4

Classification of Anemia -

inadequate production of hemoglobin

(inadequate Hgb per RBC)

Answer 4

microcytic and hypochromic

Question 5

assessment/labs to assess anemia

Answer 5

• CBCd - platelet count, RBC indices, retics (other info may be helpful)
• peripheral blood smear - morphology of cells
• hemoglobin electrophoresis - RBC deformities
• pertinent family hx
• health hx: birth, breastfeeding, supplements, dietary history (some milks do not have essential nutrients)

Question 6

Physical Findings in Anemia

Answer 6

• pallor
• glossitis- shiny tongue
• koilonychia- spoon nails
• splenomegaly- sequestration of RBC (leukemia, sickle cell)
• tachycardia- O2 deficiency
• shock

Question 7

physiologic anemia of newborn

Answer 7

• normal in newborn
• “excessive” oxygen in blood slows RBC production
• Hgb drops to 10-11 mg/dl by 12 weeks
• fetal Hgb replace by adult - O2 requirements drive higher Hgb requirements
• erythropoietin production drives more RBC synthesis and anemia of infancy ends by 10-12 months

Question 8

MC pediatric anemia

causes and characteristics

Answer 8

iron deficiency

• character: hypochromic microcytic
• causes:
  
  • excessive milk consumption (>16oz/day)
  • key is prevention - limit milk and encourage variety of foods

Question 9

when should children be screened for anemia

Answer 9

12 months

• include lead screening - associated w/ anemia
• be watchful through childhood
  
  • menstruating
  • athletes
  • poor diet

Question 10

lab results in children w/ IDA

Answer 10

• Hbg: toddlers <11, adolescents <12
• RDW: >15
• Ret-He: <25
• serum iron: <40
• serum ferritin: <10
• TIBC: >400
• transferrin saturation: <20

Question 11

Tx of IDA

Answer 11

• diet
  
  • reduce milk
  • increase iron containing foods
• iron supplement: 4-6mg/kg daily elemental Fe
  
  • constipation MC s/e- tx proactively
• retest after 3mo

Question 12

Anemia common to Mediterranean, SE Asian, AA

Answer 12

Thalassemia

• inherited anemia of abnormal Hgb
  
  • minor and alpha thalassemia
    
    • insignificant minor microcytic anemia
  • thalassemia major
    
    • life-long blood transfusions
    • complicated by Fe overload toxicity (chelation therapy required)
• screening part of newborn screening
• retested at 6-9mo after fetal Hgb cleared

Question 13

Anemias associated w/ rapid RBC turnover

Answer 13

macrocytic or megaloblastic anemia

• rapid turnover means many premature cells
• Vit B12 or folate deficiency
  
  • inadequate production of all 3 hematopoietic cell lines- thrombo, leuko, RBCs (anemia)
• other causes:
  
  • aplastic anemia
  • celiac disease
  • loss of intrincis factor req. for B12 absorption

Question 14

RBC destruction diseases

Answer 14

hemolytic disease

• Sickle cell- abnormal Hgb, RBC sensitive to pH
  
  • abnormally shaped cells in acidic environment - sequestraton and occlusive crisis (life threatening)
  • severe infections d/t splenic dysfunction
  • Fifth’s dz may cause aplastic crisis
  • Sickle cell trait
    
    • heterozygous Hgb S and Hgb A
    • hemolytic dz only in extreme cases
• G6PD deficiency
  
  • MC in AA and Mediterranean
  • illness/oxidant drug causes acute hemolysis
  • tx supportive, transfusion if CV compromise
• Hereditary Spherocytosis
  
  • stiff RBC membrane- cells collected by reticuloendothelial system
  • Dx: osmotic fragility test
  • Tx: splenectomy

Question 15

Hemolytic Disease of Newborn

Answer 15

• hemolysis of RBCs secondary to maternal antibody to infant RBCs
• Rh antibody most severe - decline d/t screening
• ABO incompatibility very common
  
  • mother type O produces anti A and B
  • these attack infant’s type A or B blood
  • early severe jaundice - significant cerebral damage w/ high bilirubin levels
  • Coombs test - confirms diagnosis

Question 16

Sx and Tx of Hemolysis

Answer 16

• Sx
  
  • anemia and sx of reduced oxygen carrying capacity
  • jaundice
• Tx
  
  • depends on etiology
  • +/- blood transfusion (depending on if transfused cells will by hemolyzed)

Question 17

Coagulopathy Presentations and Decisions

Answer 17

• abnormal bleeding in newborn (circumcision) - quick referral to hematology
• easy bruising/bleeding in older child -

PT/PTT, platelet count, fibrinogen, bleeding time, von Willebrand factor

• acute presentation of petechiae/purpura - emergent infectious disease workup

(if on face not emergent - likely coughing, vomiting)

Question 18

low platelet count

Answer 18

thrombocytopenia

• chronic vs. acute
  
  • neonatal alloimmune thrombo. purpura
    
    • maternal anti-platelet antibodies
    • risk of intracranial hemorrhage
    • IVIG to mom near delivery may prevent bleeding in newborn
  • idiopathic thrombo. purpura (ITP)
    
    • follows viral infection
    • deep dark bruising, low platelets
    • observation and protection from injury
    • prednisone and IVIG if severe

Question 19

Common Lymphadenopathies

Answer 19

• suboccipital - scalp irritant/cradle cap
• submental - dental disease, oral infection
• posterior cervical - URI
• diffuse tender nodes - severe eczema, secondary skin infection

Question 20

Uncommon Lymphadenopathy

Answer 20

• generalized (esp. supraclavicular)
• mediastinal seen on CXR
• significant systemic illness, weight loss
• nontender, firm, immovable, >2cm
• associated splenomegaly
  
  • r/o malignancy
  • r/i viral infection (EBV, CMV)