Background: The therapeutic effects of cyclophosphamide (CP) in the treatment of systemic rheumatic diseases are related to its immune suppressive activity. However effective, the application of CP is restricted due to multiple adverse effects.
Objectives: This retrospective study was conducted to determine the frequency of adverse effects attributed to CP toxicity.
Material and methods: The study involved 65 patients (17 male; 48 female) receiving intravenous CP between October 2007 and December 2010. The mean age at onset was 51.2 years (range 19-77 years). The most common diagnoses were systemic sclerosis (20), systemic lupus erythematosus (13) and vasculitis (13). The indications for treatment with CP were interstitial lung disease in the course of systemic diseases (33), vasculitis (24), glomerulonephritis (5) and changes in the central nervous system (3). The patients were administered 400-1000 mg CP in intravenous infusions at 2-16 week intervals, with the addition of sodium 2-sulfanylethanesulfonate (mesna) before and after each pulse.
Results: Out of 65 patients 40 (60%) reported adverse effects: infections in 24 (37%), nausea in 19 (29%), vomiting in 11 (17%), abdominal pain in 7 (11%) and pancytopenia in one, leading to cessation of the therapy. No association was found between the frequency of side effects and the treatment duration (p = 0.632), age (p = 0.852), diagnosis (p = 0.171) or nominal dose (p = 0.321).
Conclusions: As knowledge about CP continues to increase, this medication remains a safe way to treat many rheumatic diseases.
Keywords: adverse effects; cyclophosphamide; rheumatic diseases.