Pancytopenia

Differential Diagnosis of Pancytopenia
Helpful to think in terms of mechanisms of whether the problem is in the bone marrow and what is going on there, vs outside the bone marrow.

1.   Hypocellular Bone Marrow – most common manifestation of this is Aplastic Anemia.

• Idiopathic
• Radiation
• Chemotherapy
• Chemicals (e.g. Benzene)
• Idiosyncratic medication reactions
• Viruses – HIV, Parvovirus B19, HHV-6, EBV, Hepatitis viruses (most commonly Hepatitis B)
• Graft vs Host Disease
• Autoimmune – SLE, etc
• Paroxysmal Nocturnal Hemoglobinuria

2.  Cellular Bone Marrow with Ineffective Hematopoiesis  - Myelodysplastic Syndromes

3.  Marrow Replacement or Infiltration

• Myelofibrosis
• Leukemia/Lymphoma
• Metastatic tumors to the bone

4.   Problem outside the Bone Marrow:   Hypersplenism,  Sepsis – multifactorial reasons, but mostly from consumption and DIC

 

 

Diagnostic approach to pancytopenia:

a) Review the smear! As internists, we should be comfortable looking for anomalies that raise red flags, such as spherocytes and schistocytes.

b) Reticulocyte count - must adjust for the fact that with worsening anemia, retics leave the BM earlier and have a longer lifespan in periphery --> reticulocyte index.

c) LFTs to eval for hepatitis

d) B12 and folate

e) Hemolysis labs: Direct Coombs, LDH, haptoglobin

f) Iron studies

g) Viral studies: EBV, CMV, HIV

h) ANA

i) PNH clone via flow cytometry

j) Abdominal u/s to evaluate for splenomegaly

k) BM bx: reticulin staining evaluates for myelofibrosis

 

 

 

(Chanu Rhee MD, 5/10/11)