title: Selective gut decontamination with nalidixic acid or trimethoprim-sulfamethoxazole for infection prophylaxis in neutropenic cancer patients: relationship of efficacy to antimicrobial spectrum and timing of administration.
abstract: Eighty-four cancer patients at risk of infection because of neutropenia were randomized to receive nalidixic acid as an alternative to trimethoprim-sulfamethoxazole (TMP-SMX) for infection prophylaxis. Infections were documented significantly earlier and more often among patients who entered the trial with neutrophil counts of less than 0.1 X 10(9)/liter. TMP-SMX recipients experienced fewer microbiologically documented infections and bacteremias and were free of infection for a higher proportion of days with severe neutropenia (less than 0.1 X 10(9)/liter) than nalidixic acid recipients. Gram-negative bacillary and Staphylococcus aureus infections accounted for the major differences. Although the majority of aerobic gram-negative bacilli were eliminated from the feces after 1 week of prophylaxis with either agent, TMP-SMX was proved superior to nalidixic acid in this regard and was associated with acquired drug resistance by gram-negative bacilli less frequently. Both agents selected for colonization and subsequent infection by gram-positive cocci. Our data suggest that prophylaxis is most likely to be effective if administered to patients for at least 1 week before they become severely neutropenic. Nalidixic acid used as a single agent in doses of 4 g daily, however, cannot be recommended as an alternative to TMP-SMX for infection prophylaxis in neutropenic cancer patients.
authors.forename: E J
authors.initials: EJ
authors.lastname: Bow
authors.forename: E
authors.initials: E
authors.lastname: Rayner
authors.forename: B A
authors.initials: BA
authors.lastname: Scott
authors.forename: T J
authors.initials: TJ
authors.lastname: Louie
mesh_terms: D000380:Agranulocytosis / Q000150:complications*; D000970:Antineoplastic Agents / Q000009:adverse effects; D001419:Bacteria / Q000302:isolation & purification; D001424:Bacterial Infections / Q000209:etiology / Q000517:prevention & control*; D002986:Clinical Trials as Topic; D004334:Drug Administration Schedule; D004338:Drug Combinations / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D009181:Mycoses / Q000209:etiology; D009268:Nalidixic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D009369:Neoplasms / Q000150:complications*; D009503:Neutropenia / Q000139:chemically induced / Q000150:complications*; D011897:Random Allocation; D013420:Sulfamethoxazole / Q000008:administration & dosage / Q000627:therapeutic use*; D014295:Trimethoprim / Q000008:administration & dosage / Q000627:therapeutic use*; D015662:Trimethoprim, Sulfamethoxazole Drug Combination
chemical_list: D000970:Antineoplastic Agents; D004338:Drug Combinations; D009268:Nalidixic Acid; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D014295:Trimethoprim; D013420:Sulfamethoxazole