Zidovudine therapy protects against Salmonella bacteremia recurrence in human immunodeficiency virus-infected patients.

Fifty-five human immunodeficiency virus-infected patients with Salmonella bacteremia were studied to assess the rate of and causes for recurrence and to determine the influence on relapse of zidovudine, cotrimoxazole, and antimicrobial suppressive therapy according to the susceptibility of the isolates. Overall, 22% of patients relapsed in a median time of 87 days, independent of CD4 cell count, Salmonella serotype, or duration of antibiotic therapy. The use of zidovudine was associated with the lowest rate of recurrences compared with cotrimoxazole or amoxicillin as suppressive therapy. In the microbiologic assay, zidovudine showed bactericidal effect on Salmonella species at current dosages, and resistance to zidovudine was uncommon (2 cases, 4%). Due to its direct effect on Salmonella species, a zidovudine-containing regimen may protect against the recurrence of the disease.