Today we discussed an approach to the patient with pancytopenia
This is an indication for a bone marrow aspirate and biopsy, which usually shows increased or decreased marrow cells:
Hypocellular marrow
-Marrow toxins: May be dose-dependent, predictable as with chemotherapeutic agents, immunomodulators (methotrexate, cyclophosphamide, etc) or idiosyncratic (chloramphenicol, sulfa drugs, phenytoin, many others); radiation, EtOH
-Infection: Parvovirus B12, EBV, HIV, HHV-6, viral hepatitis; severe sepsis
-Immune: SLE, RA (rare), graft-versus-host
-PNH
-Idiopathic stem cell failure
Hypercellular marrow
-MDS, leukemias, lymphomas, myeloma
-Nutritional- severe megaloblastic anemia (B12, folate)
-Marrow replacement/infiltration: myelophthisic anemia , myelofibrosis, granulomatous disease (TB, sarcoid, fungal), solid tumor metastases (prostate and breast are most common)
The topic of the MGUS and multiple myeloma 'spectrum' came up. Here are some helpful criteria based on the NEJM review paper cited below:
MGUS
Marrow plasma cells less than 10% and M-protein (in blood) less than 30g/L
No clinical manifestations
Smouldering MM
Marrow plasma cells at least 10% and/or M-protein at least 30g/L
No clinical manifestations
Multiple myeloma
Marrow plasma cells over 10% and/or M-protein at least 30g/L
Clinical features of hypercalcemia, renal failure, anemia, bone lesions, infections, plasmacytomas
Waldenstrom's macroglobulinemia
Marrow plasma cells over 10% and M-protein over 30 (IgM)
Clinical features of anemia, bleeding, organomegaly, IgM immunoglobulin
Primary amyloidosis (AL)
Marrow plasma cells less than 10% and M-protein less than 30
Clinical fearures of fatigue, wt loss, purpura, nephrotic syndrome, CHF, neuropathy, orthostatic hypotension, massive hepatomegaly
Links:
Click here for a "medical mystery" from NEJM on panyctopenia
Click here for an excellent review paper on MGUS/myeloma differentiation
