Oral ciprofloxacin therapy for chronic contiguous osteomyelitis caused by aerobic gram-negative bacilli.

Twenty adult patients with chronic contiguous osteomyelitis caused by aerobic gram-negative bacilli were enrolled in an open, prospective cooperative study to determine the effect of oral ciprofloxacin therapy in a dosage of 750 mg every 12 hours. There were 14 men and six women, with a mean age of 55 years. Fifteen of the 20 patients had undergone previous unsuccessful attempts at therapy; seven of the 20 patients had clinically important underlying diseases. Osteomyelitis involved the sternum in three patients and the bones of the lower extremity in 17 patients. Initial surgical debridement was performed in 15 of 20 patients. The predominant organism isolated was Pseudomonas aeruginosa, which was found as a single pathogen in 13 patients and as part of a polymicrobic flora in three patients. Based on posttreatment follow-up of seven to 21 months, clinical cure was achieved in 13 of 20 (65 percent) patients and bacteriologic cure was achieved in 14 of 20 (70 percent) patients. Minimal inhibitory concentrations of ciprofloxacin against P. aeruginosa increased during therapy in four of 16 (25 percent) patients. Minor gastrointestinal side effects occurred in five patients. Oral ciprofloxacin was an effective and safe therapy in patients with chronic contiguous osteomyelitis due to aerobic gram-negative bacilli.

Randomized trial of ciprofloxacin compared with other antimicrobial therapy in the treatment of osteomyelitis.

Thirty adults (mean age, 52 years) were enrolled in a randomized, comparative trial of oral ciprofloxacin (750 mg twice daily) and other antimicrobial therapies. Etiologic agents included Enterobacteriaceae (18 isolates), Pseudomonas aeruginosa (16 isolates), and Staphylococcus aureus (four isolates). Seven of 14 (50 percent) ciprofloxacin-treated infections are cured at up to 13 months follow-up and three infections appear improved. Treatment failure or relapse has occurred in four patients. Sixteen patients received other antimicrobial therapy and 11 patients (65 percent) remain without infection and have healed wounds, with follow-up from one to 13 months. One patient has had a relapse, while improvement is apparent in four patients. Complications that occurred in this group included drug-related neutropenia (two patients), diarrhea (two patients), drug allergy (one patient), and catheter-related staphylococcal cellulitis (one patient). Oral ciprofloxacin therapy for chronic osteomyelitis caused by susceptible organisms appears to be as effective as other antimicrobial therapies.

Cefoxitin inactivation by Bacteroides fragilis.

We have surveyed the susceptibility of 1,575 clinical isolates of the Bacteroides fragilis group of organisms to cefoxitin and eight other antimicrobial agents. Eleven isolates, 0.7% of the total, were highly cefoxitin resistant and had minimum inhibitory concentrations of greater than or equal to 64 micrograms/ml. These isolates were also resistant to other beta-lactam antibiotics. Of 11 isolates, 4 were able to inactivate cefoxitin in broth cultures, as measured by microbiological and high-pressure liquid chromatography assays. Two distinct patterns of cefoxitin breakdown products were detected by high-pressure liquid chromatography analysis. The beta-lactamase inhibitors clavulanic acid and sulbactam failed to show synergism with cefoxitin. These data demonstrate that members of the B. fragilis group have acquired a novel resistance mechanism enabling them to inactivate cefoxitin.

Candida infections in surgical patients.

Serious Candida infections were seen in 55 surgical patients from January 1977 through December 1980. Most of the patients had compromising underlying conditions and many were elderly. Broad-spectrum antibiotics and total parenteral nutrition (TPN) appeared to predispose patients to Candida infections. Mortality rate from Candida was 38%. A high percentage of patients with positive blood or bile cultures died as a result of Candida infection. Therapy with intravenous amphotericin B was highly effective if given in adequate dosage. No patient receiving more than 200 mg of amphotericin B died, but the mortality rate was 56% in those receiving lower doses.

Sequence homology of clindamycin resistance determinants in clinical isolates of Bacteroides spp.

The sequence homology of clindamycin resistance (Clnr) determinants was studied in 16 Clnr Bacteroides strains. The isolates were surveyed for plasmid content, homology with the Clnr determinant of pBFTM10, and ability to transfer Clnr. The Clnr DNA probes used in the Southern hybridizations were pBFTM10 and a plasmid derivative containing an EcoRI fragment of pBFTM10 cloned into Escherichia coli. A total of 13 of 16 Clnr strains also carried tetracycline resistance, and 15 of 16 Clnr Bacteroides isolates showed homology with the Clnr determinant of pBFTM10. These data suggest that the previously characterized Clnr determinant of pBFTM10 is widely distributed in nature and may be found on either a plasmid or the chromosome. The Clnr Bacteroides fragilis strain which lacked homology with pBFTM10 also had different transfer properties; thus, more than one type of Clnr determinant may exist in Bacteroides spp.

Management of an anaerobic infection in a prosthetic knee with long-term antibiotics alone: a case report.

A 74-year-old woman had a spherocentric arthroplasty performed on her left knee. After four postoperative weeks, she developed and swelling in the joint. An anaerobic streptococcus was isolated from a joint aspirate. The patient was treated solely with knee immobilization and intravenous penicillin G for five weeks. Joint aspirates at the end of treatment and six months posttreatment were sterile. However, after ten posttreatment months, the peptostreptococcal infection recurred. Sterile joint aspirates six months after treatment are insufficient evidence of cure in prosthetic joint infections.