Acute sternal osteomyelitis caused by Streptococcus milleri

We wish to report a case of acute sternal osteomyelitis caused by Streptococcus milleri which appears not to have been reported as a cause of this condition before. A 78-year-old lady with chronic schizophrenia was referred from the local psychiatric hospital. She had features of large bowel obstruction and a low grade fever. Her gastrointestinal symptoms resolved on conservative management but she continued to have a low grade fever. One week after her admission she developed a soft tissue swelling in the upper sternal region with no local signs of acute inflammation. A plain X-ray at this stage showed a soft tissue mass overlying the proximal sternum containing gas but no sternal destruction. Needle aspiration of the swelling yielded 2 ml pus from which was cultured S. milleri sensitive to penicillin, erythromycin and trimethoprim. She was treated with 2 mega units of benzylpenicillin IV, 4 hourly. X-ray examination repeated after 1 week, showed sternal destruction consistent with acute osteomyelitis. Surgical drainage of the abscess and debridement of the sternal bony fragments was carried out. At exploration a 3 cm diameter area of complete destruction of the sternum involving both cortices was found but the periosteum was intact. Penicillin was continued for a total of 6 weeks and she made a satisfactory recovery.