Aztreonam in the treatment of serious orthopedic infections

Aztreozam was evaluated in the treatment of a variety of orthopedic infections. Included were 17 patients with osteomyelitis, three with purulent arthropathy with prostheses, and 16 with superficial infections secondary to trauma or surgical procedure. Pathogens were gram-negative bacilli sensitive to aztreonam. Concomitant antibiotics were administered for gram-positive cocci that were present initially or by superinfection. Infecting organisms included Pseudomonas aeruginosa (minimal inhibitory concentration 4 to 16 micrograms/ml), Serratia marcescens, Enterobacter cloacae, Enterobacter sakazakii, Morganella morganii, Citrobacter freundii, Proteus vulgaris, Proteus rettgeri, Acinetobacter calcoaceticus and others (all with minimal inhibitory concentrations less than 1.0 microgram/ml). Dosage of aztreonam was 2 to 8 g per day administered intravenously or intramuscularly for five to 52 days. Clinical and bacteriologic responses were adequate in all instances. Recurrences were observed in two individuals with osteomyelitis and one with purulent arthropathy. Adverse clinical or laboratory observations were infrequent and inconsequential.