Thirty-one adult patients with infections due to anaerobic bacteria were treated with cefamandole. BacterQides fragilis group (17) and Bacteroides melaninogenicus (13) were the most frequent anaerobes isolated. Duration of therapy varied from 2 to 49 days. Results were judged satisfactory in 26 cases, and unsatisfactory in 1 case. Four cases could not be evaluated. Adverse reactions occurred in 16 patients and included positive direct Coombs' test without hemolysis, transient liver function abnormalities, phlebitis, reversible neutropenia, fever, eosinophilia, and toxic epidermal necrolysis. The more significant reactions were associated with prolonged therapy. None was lethal. These data suggest that cefamandole is effective in treatment of most anaerobic infections.Cefamandole nafate, a new parenteral cephalosporin, has a broader spectrum of activity against both aerobic and anaerobic bacteria than cephalothin or cefazolin (9, 10). In vitro it is active against a wide range of gram-positive and gram-negative aerobic and anaerobic bacteria (5, 13). On the basis of these reports, we evaluated cefamandole in the treatment of anaerobic infections.(The results presented here have been reported, in part, in abstract form [R. N. Greenberg, M. C. Scalcini, C. V. Sanders, and A. C. Lewis, Program Abstr. Intersci. Conf. Antimicrob. Agents Chemother. 18th, Atlanta, Ga., Abstr. no. 360, 1978].) MATERIALS AND METHODS Patients. Thirty-one patients with anaerobic infections who had been hospitalized at Charity Hospital of New Orleans between July 1977 and August 1978 were admitted to the study. Patients were included only if they (i) were over 13 years of age, (ii) were not pregnant, (iii) had no history of allergy to penicillin or cephalosporin antibiotics, and (iv) had not received any antibiotics once culture specimens were taken. Informed consent was obtained from each patient before cefamandole therapy was started.In all but three patients anaerobic organisms were isolated from culture material. In the three patients in whom anaerobes were not recovered, the pus obtained smelled foul, its Gram stain revealed a variety of pleomorphic gram-negative organisms, and its culture did not grow any aerobic gram-negative organism. The clinical diagnoses in these three patients were lung abscess, salpingitis, and postabortal endometritis.Isolation and identification of bacteria. Most specimens were collected by transtracheal aspiration (15) or by aspiration of material directly from an abscess (9). The specimens were immediately injected into oxygen-free vials (Port-a-Cul; Baltimore Biological Laboratory [BBL], Cockeysville, Md.) and transported to the laboratory. When specimens could not be aspirated, specifically in cases of postpartum, postabortal, or intrauterine device-related endometritis, the endocervical pus was collected with a sterile swab and transported to the laboratory in oxygen-free tubes (BBL).Specimens for anaerobic culture were inoculated onto prereduced blood agar and kanamycin-vancomycin blood agar plates and i...