Infections with providence bacilli: A clinical and bacteriologic study

Infections with Providence bacilli among the patients hospitalized at the University of Minnesota Medical Center in 1968 and 1969 are reported. Fifty-four patients had urinary tract infections, four had pneumonia, four had postoperative wound infections, and one patient had septicemia in addition to pneumonia and postoperative wound infections. Three-fourths of the patients were male. Fifty-two of the patients with urinary tract infections had underlying urologic disorders, neurogenic bladder dysfunction and congenital urologic anomalies accounting for 80 per cent of these. Six of the patients with respiratory tract and postoperative wound infections survived. All were treated with kanamycin. The patient with septicemia died. Biochemical tests and serotyping demonstrated at least twenty biotypes. However, localization of more than 90 per cent of the patients to two hospital departments and the frequent occurrence at the same time of two to three patients infected with identical strains suggested that many of the organisms were hospital acquired. Kanamycin, carbenicillin, gentamicin and nalidixic acid exhibited considerable activity against the Providence group. Of the strains 97 per cent were sensitive to 1.6 μg/ml of kanamycin or less. Great variations in virulence between strains were observed. LD 50 for mice varied from 2.9 × 10 2 to 7.4 × 10 7 organisms. Strains isolated from patients with septicemia, pneumonia and postoperative wound infections were more virulent than those isolated from patients with urinary tract infections. Five patients with Providence septicemia hospitalized from 1960 to 1968 are described. One patient treated with kanamycin and one with chloramphenicol survived.