Pancytopenia associated with low-dose methotrexate therapy – case reports

Abstract

Background: Methotrexate has gained wide acceptance due to its efficacy in a variety of inflammatory rheumatological disorders. However, it has the potential to cause serious, life-threatening complications. Risk-factors that are important in the development of pancytopenia include advanced age, impared renal function, low folic acid levels, decreased serum albumin and concurrent ingestion of medications involved in folate metabolism. Patients and results of treatment: In this paper, three patients who developed pancytopenia while being treated with low-dose methotrexate over the past years are presented. Factors for the developement of pancytopenia in these patients were: impaired renal function (first patient), concurrent use of trimethoprim-sulfamethoxazole (second patient) and folic acid deficiency (third patient). Conclusions: With the increasing long-term use of methotrexate, it is important that patients should be monitored during treatment for haematological side-effects, as pancytopenia can be a late manifestation. Furthermore, more attention should be paid to risk factors predisposing hematological toxicity of methotrexate before commencing this drug