Definition
Hemoglobin below age appropriate norms (Reduction in O2 transport to tissues –> tissue hypoxia –> compensation (increased CO, increased 2,3DPG))
Pathophysiology
- Decreased production
- Increased loss
- Increased destruction
Differential Diagnosis
- Nutrition (Fe, folate, B12)
- Autoimmune hemolysis = jaundice
- Toxins (Pb)
- Neoplasm
- Trauma (hemorrhage)
- Infection (malaria, parvovirus)
- Metabolic (decreased Epo, TSH)
- Ischemia
- Congenital/Degenerative
- Hgb (thalassemias, sickle cell)
- Structural (hereditary spherocytosis – AD, cholecystectomy at early age, jaundice…)
- Enzymopathies (G-6-P)
History
- Onset, duration, symptoms (eat, sleep, irritability, bruise/bleed, B symptoms, transfusions) – CNS, Resp, CVS, GI (blood loss), GU
- Acutely: pallor, fatigue, irritability, lethargy, SOB, poor exercise tolerance, headache, syncope, bone pain
- Past medical history – birth (ABO/Rh, jaundice, GA, IUGR), surgeries, chronic problems (renal)
- Family history and nationality
- Nutritional history
- Medications and allergies
Physical Exam
- Vitals
- Growth
- HEENT ( conjunctiva, LA)
- CVS – CHF if severe
- Abdominal – rectal for occult blood
- Lymph nodes
- Extremities (palms, nailbeds, bruise/petechiae, edema)
- CNS
Labwork
- CBCD (Hgb, MCV, WBC, plt)
- Blood smear
- Reticulocyte count
- Ferritin (acute phase reactant if low helpful, if high do Fe panel)
- Fe panel: TIBC (high), Fe saturation index (low)
- RBC folate
- DAT – if positive then haemolytic disease of newborn
Microcytic: Fe, Thalassemia, Pb
Normocytic: Hemolytic anemia, ACD, hemorrhage
Macrocytic: Folate, B12
Treatment
- 6mg/kg/d elemental Fe (divided TID)
- Will see increased reticulocytes in 1 wk, if not consider poor absorption (Celiac, IBD)
- Hgb should increase 10-20g/week, normal in 4-6wk but continue for 3 more months
- May cause dark teeth, constipation, dark stools