Hematologic toxicity with immunosuppression

Chronic immunosuppression with azathioprine increases the risk of neoplasia. Physicians using this drug should be familiar with this risk as well as with the mutagenic potential to men and women and with possible hematologic toxicities. 

Thrombocytosis is another common hematologic finding with active rheumatoid arthritis. Platelet counts rise and fall in direct correlation with disease activity in many patients. Thrombocytopenia may result from toxicity of gold salts, penicillamine, or immunosuppressive therapy. Thrombocytopenia also may be observed in Felty s syndrome or vascuhtis. 

The longer-term effects of immunosuppression, and in particular the residual hematological and immunological abnormalities in patients with aplastic anemia treated with antilymphocjde globulin, have been documented there is toxicity to hemopoietic cells, eventually leading to clonal marrow diseases years after treatment (37). Paroxysmal nocturnal hemoglobinuria, refractory sideroblastic anemia, chronic myelomonocytic leukemia, or acute leukemia can develop 4-10 years after treatment (40). 

Commonly reported adverse effects of mycophenolate mofetil include gastrointestinal toxicity (diarrhea, nausea, and vomiting), hematologic effects (anemia, neutropenia, and thrombocytopenia), and an increased incidence of viral and bacterial infections. Lym-phoproliferative disease or lymphoma has developed in up to 1 % of patients who received mycophenolic acid with other immunosuppressive agents. 

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