Septic arthritis of the sternoclavicular joint due to gram-positive microorganisms.

Infectious arthritis of the sternoclavicular (SC) joint is a known complication of intravenous drug abuse. Most reported cases have been caused by gram-negative microorganisms. Patients with this form of septic arthritis usually have protracted illnesses and require both medical and surgical, therapy. During 18 months we saw four cases of SC septic arthritis cause by gram-positive microorganisms. Three cases were related to heroin use and Staphylococcus aureus was the causative organisms. Streptococcus pneumoniae was isolated in the remaining patient. All patients had the abrupt onset of SC joint swelling and tenderness as the initial complaint and all responded favorably to appropriate intravenous drug therapy.