Co-trimoxazole in patients with haematological malignancies: a review of 10-years' clinical experience.

Co-trimoxazole has been used in a hospital for over 10 years as a major antibacterial agent in the treatment of malignant haematological diseases. Routine selective gut decontamination with co-trimoxazole combined with colistine and an antifungal agent has led to a reduction in infections in neutropenic patients from 40% to 25% since the strategy was adopted, and this had been accompanied by a change in the most frequent pathogens, from Gram-negative to Gram-positive organisms. Co-trimoxazole has proved to be the drug of choice for Pneumocystis carinii infections. Finally, it is used as first-line therapy in febrile immunosuppressed patients who are not on selective decontamination, with an efficacy of over 90%. Apart from mild abdominal discomfort, an elevated allergy rate of 14% in patients with overt leukaemia is a major disadvantage. On the other hand, substantial prolongation of episodes of bone marrow aplasia has not been observed.