Effect of quinolones on the duration of salmonella carriage after acute salmonellosis

Abstract

Carlstedt et al. (I) studied the effect on the duration of salmonella carriage of norfloxacin treatment of acute salmonellosis during an outbreak of infection with Salmonella typhimurium. They found that norfloxacin treatment did not shorten the carrier stagc. The authors state that ... no controlled study has been published on the effect of quinolones on salmonella convalescent carriage.'. However. in a rcccnt study during an outbreak of food poisoning caused by S. typhimurium, we investigated the duration of fecal excretion of salmonella for patients who received no antibiotic treatment and for those treated with ofloxacin (2). 20 inpatients with positive stool cultures received 200 mg ofloxacin twice daily for 5 days. 21 outpatients with positive stool cultures did not receive any drug. In the untreated group. 18/21 patients (85.7%) were excreting S. typhimurium after 8 days and 6/21 (28.5%) after 18 days. In the ofloxacin-treated group 5/20 patients (25%) were excreting S. typhimurium after 8 days and 1/20 (5%)) after 18 days. The differcnces were statistically significant (Student's I test). Thus. wc found that ofloxacin shortens the duration of excretion of S. typhimurium in feces. In somc recent studies it has been shown that ciprofloxacin also shortens the carrier stage after acute salmoncllosis (3,J). Carlstedt et al. state that .'... it seems unlikely that other quinolones would he more successful. However. there may he differences hctwccn the effect of norfloxacin and other quinolones on the duration of fecal excretion of salmonella in salmonella enterocolitis depending on different pharmacokinetics.