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Acute sternal osteomyelitis caused by Streptococcus milleri
IO6
Letters to the Editor
infection mimics malignancy.2 However, unlike the infection reported by Raz and L e v in a diabetic subject, the progress of disease in our previously healthy patient was entirely benign.
Regional Infectious Diseases Unit, Fazakerley Hospital, Longmoor Lane, Liverpool L9 7AL, U.K.
F. J. Nye
References I. Raz R, Lev A. Primary abdominal actinomycosis in a diabetic woman--an intractable disease. J Infect 1992; 25: 303-306. 2. Lau Wy, Boey J, Fau ST, et al. Primary actinomycosis of the abdominal wall. Aust N Z J Surg 1986; 56: 873-875.
Acute sternal osteomyelitis caused by Streptococcus milleri Accepted for publication 3o January 1993 Sir, 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 f r o m the local psychiatric hospital. She had features of large bowel obstruction and a low grade fever. She was reported to have had a chest infection I week before her referral, and there was left basal consolidation on chest X-ray. She had not received any antibiotics for this infection. H e r gastrointestinal s y m p t o m s resolved on conservative m a n a g e m e n t but she continued to have a low grade fever. One week after her admission she developed a soft tissue swelling in the u p p e r sternal region with no local signs of acute inflammation. A plain X - r a y 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 f r o m which was cultured S. milleri sensitive to penicillin, e r y t h r o m y c i n and trimethoprim. She was treated with 2 mega units of benzylpenicillin IV, 4 hourly. X - r a y examination repeated after I week, showed sternal destruction consistent with acute osteomyelitis. Surgical drainage of the abscess and d6bridement of the sternal b o n y fragments was carried out. At exploration a 3 cm diameter area of complete destruction of the sternum involving b o t h cortices was found but the periosteum was intact. Penicillin was continued for a total of 6 weeks and she m a d e a satisfactory recovery. P r i m a r y osteomyelitis of the sternum is exceedingly rare, the majority of cases being reported in either drug addicts or i m m u n o c o m p r o m i s e d patients. 1, 2 S. milleri forms part of the normal oropharyngeal and intestinal flora and belongs to the viridans group. T h e main pathological characteristic of the organism is its tendency to f o r m abscesses in different organs. It has been isolated f r o m dental, cerebral and p l e u r o p u l m o n a r y (pneumonia and e m p y e m a ) abscesses and also in cases of endocarditis. I n t r a - a b d o m i n a l abscesses due to S. milleri (hepatic, pelvic, appendiceal and peritoneal are m o r e c o m m o n and usually secondary to underlying abdominal pathology. 3 Staphylococcus aureus is the c o m m o n e s t cause of osteomyelitis in other bones and the cause of secondary sternal osteomyelitis after open heart surgery and chest trauma. T h e m o s t likely cause of sternal osteomyelitis in this case is spread of the organism f r o m a p l e u r o p u l m o n a r y source as she had an untreated chest infection a week before
Letters to the Editor
lO7
admission. Blood culture taken before antibiotic therapy was sterile after 7 days' incubation. A definite clinical diagnosis of acute sternal osteomyelitis is difficult. X - r a y examination of the s t e r n u m offers little assistance in the early stages as was evident in this case. F r a n k b o n y destruction and severe demineralisation are the only radiological signs that m a y help to distinguish sternal osteomyelitis f r o m infections limited to the soft tissues, but these changes are relatively l a t e ) Although the diagnostic yield f r o m bone scans is m u c h better than f r o m plain X rays, 5 computerised t o m o g r a p h y ( C T ) has been r e c o m m e n d e d as the investigation of choice. C T , because it is able to discern subtle differences in tissue density and can view tissues in axial planes~ assists in distinguishing between normal and pathological structures. ~ I t assists in treatment by guiding needle biopsies of infected tissues, and also provides vital information on the extent of the disease which helps to plan appropriate surgical treatment. W e believe, therefore, that C T is the examination of choice in suspected cases of sternal osteomyelitis. T h e m a n a g e m e n t of uncomplicated sternal osteomyelitis is conservative. A p propriate antibiotic therapy for 4-6 weeks is the treatment of choice with surgery assuming a secondary role either to assist in diagnosis or by limited resection of residual necrotic tissues. 7 Preservation of the posterior sternal periosteum is important for maintaining and avoiding chest wall deformity in such patients. M a n a g e m e n t by radical sternal resection with reconstruction of the chest wall defect has been reported to give minimal after effects on p u l m o n a r y function, s T h i s procedure is not indicated in the m a n a g e m e n t of acute sternal osteomyelitis.
*Department of Surgery, tDepartment of Microbiology, Craigavon Area Hospital, Craigavon, County Armagh, Northern Ireland, BT63 5QQ, U.K.
M. S. Khan* N. N. Damani~f E. J. Mackle*
References
I. Roca RP, Yoshikawa T T . Primary infection in heroin users: a clinical characterisation, diagnosis and therapy. Clin Orthop Rel Res I979; x44: z38-z48. 2. Estrov A, Resnitzky P, Shenker Y, Berribi A, Hurwitz N. Candidaemia and sternal Candida albicam osteomyelitis in a patient with chronic lymphatic leukaemia, lsr J Med Sci 1984; 20 (8): 711-714. 3. Gossling J. Occurrence and pathogenicity of the Streptococcus milleri Group. Rev Infect Dis 1988; 1o (2): 257-285. 4. Rosenthal DI, Johnson RE), Oot RF. Evaluation of postoperative osteomyelitis of the sternum using tomography and computerised tomography, ff Can Assoc Radiol 1984; 35 (I): 24-27. 5- Mittapali MR. Value of bone scan in primary sternal osteomyelitis. South Medff 1979; 72 (12): 16o3-16o 4 . 6. Riddlesberger M M Jr, Kuhn JP. The role of computerised tomography in diseases of musculoskeletal system, ff Comp Tomo 1983; 7 (I): 85-89. 7. Jara FM, Yap A, Toledo-Pereyra LH, Magilligan DJ Jr. The role of surgery in primary osteomyelitis of the chest wall. ff Thorac Cardiovasc Surg 1979; 77 (I): 147-15o. 8. Meadows JA, Staats BA, Pairolero PC, Rodarte Jr, Arnold PG. Effects of resection of the sternum and manubrium in conjunction with muscle transposition on pulmonary function. Mayo Clin Proc 1985; 6o (9): 604-609. * Address correspondence to Dr N. N. Damani
Letters to the Editor
infection mimics malignancy.2 However, unlike the infection reported by Raz and L e v in a diabetic subject, the progress of disease in our previously healthy patient was entirely benign.
Regional Infectious Diseases Unit, Fazakerley Hospital, Longmoor Lane, Liverpool L9 7AL, U.K.
F. J. Nye
References I. Raz R, Lev A. Primary abdominal actinomycosis in a diabetic woman--an intractable disease. J Infect 1992; 25: 303-306. 2. Lau Wy, Boey J, Fau ST, et al. Primary actinomycosis of the abdominal wall. Aust N Z J Surg 1986; 56: 873-875.
Acute sternal osteomyelitis caused by Streptococcus milleri Accepted for publication 3o January 1993 Sir, 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 f r o m the local psychiatric hospital. She had features of large bowel obstruction and a low grade fever. She was reported to have had a chest infection I week before her referral, and there was left basal consolidation on chest X-ray. She had not received any antibiotics for this infection. H e r gastrointestinal s y m p t o m s resolved on conservative m a n a g e m e n t but she continued to have a low grade fever. One week after her admission she developed a soft tissue swelling in the u p p e r sternal region with no local signs of acute inflammation. A plain X - r a y 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 f r o m which was cultured S. milleri sensitive to penicillin, e r y t h r o m y c i n and trimethoprim. She was treated with 2 mega units of benzylpenicillin IV, 4 hourly. X - r a y examination repeated after I week, showed sternal destruction consistent with acute osteomyelitis. Surgical drainage of the abscess and d6bridement of the sternal b o n y fragments was carried out. At exploration a 3 cm diameter area of complete destruction of the sternum involving b o t h cortices was found but the periosteum was intact. Penicillin was continued for a total of 6 weeks and she m a d e a satisfactory recovery. P r i m a r y osteomyelitis of the sternum is exceedingly rare, the majority of cases being reported in either drug addicts or i m m u n o c o m p r o m i s e d patients. 1, 2 S. milleri forms part of the normal oropharyngeal and intestinal flora and belongs to the viridans group. T h e main pathological characteristic of the organism is its tendency to f o r m abscesses in different organs. It has been isolated f r o m dental, cerebral and p l e u r o p u l m o n a r y (pneumonia and e m p y e m a ) abscesses and also in cases of endocarditis. I n t r a - a b d o m i n a l abscesses due to S. milleri (hepatic, pelvic, appendiceal and peritoneal are m o r e c o m m o n and usually secondary to underlying abdominal pathology. 3 Staphylococcus aureus is the c o m m o n e s t cause of osteomyelitis in other bones and the cause of secondary sternal osteomyelitis after open heart surgery and chest trauma. T h e m o s t likely cause of sternal osteomyelitis in this case is spread of the organism f r o m a p l e u r o p u l m o n a r y source as she had an untreated chest infection a week before
Letters to the Editor
lO7
admission. Blood culture taken before antibiotic therapy was sterile after 7 days' incubation. A definite clinical diagnosis of acute sternal osteomyelitis is difficult. X - r a y examination of the s t e r n u m offers little assistance in the early stages as was evident in this case. F r a n k b o n y destruction and severe demineralisation are the only radiological signs that m a y help to distinguish sternal osteomyelitis f r o m infections limited to the soft tissues, but these changes are relatively l a t e ) Although the diagnostic yield f r o m bone scans is m u c h better than f r o m plain X rays, 5 computerised t o m o g r a p h y ( C T ) has been r e c o m m e n d e d as the investigation of choice. C T , because it is able to discern subtle differences in tissue density and can view tissues in axial planes~ assists in distinguishing between normal and pathological structures. ~ I t assists in treatment by guiding needle biopsies of infected tissues, and also provides vital information on the extent of the disease which helps to plan appropriate surgical treatment. W e believe, therefore, that C T is the examination of choice in suspected cases of sternal osteomyelitis. T h e m a n a g e m e n t of uncomplicated sternal osteomyelitis is conservative. A p propriate antibiotic therapy for 4-6 weeks is the treatment of choice with surgery assuming a secondary role either to assist in diagnosis or by limited resection of residual necrotic tissues. 7 Preservation of the posterior sternal periosteum is important for maintaining and avoiding chest wall deformity in such patients. M a n a g e m e n t by radical sternal resection with reconstruction of the chest wall defect has been reported to give minimal after effects on p u l m o n a r y function, s T h i s procedure is not indicated in the m a n a g e m e n t of acute sternal osteomyelitis.
*Department of Surgery, tDepartment of Microbiology, Craigavon Area Hospital, Craigavon, County Armagh, Northern Ireland, BT63 5QQ, U.K.
M. S. Khan* N. N. Damani~f E. J. Mackle*
References
I. Roca RP, Yoshikawa T T . Primary infection in heroin users: a clinical characterisation, diagnosis and therapy. Clin Orthop Rel Res I979; x44: z38-z48. 2. Estrov A, Resnitzky P, Shenker Y, Berribi A, Hurwitz N. Candidaemia and sternal Candida albicam osteomyelitis in a patient with chronic lymphatic leukaemia, lsr J Med Sci 1984; 20 (8): 711-714. 3. Gossling J. Occurrence and pathogenicity of the Streptococcus milleri Group. Rev Infect Dis 1988; 1o (2): 257-285. 4. Rosenthal DI, Johnson RE), Oot RF. Evaluation of postoperative osteomyelitis of the sternum using tomography and computerised tomography, ff Can Assoc Radiol 1984; 35 (I): 24-27. 5- Mittapali MR. Value of bone scan in primary sternal osteomyelitis. South Medff 1979; 72 (12): 16o3-16o 4 . 6. Riddlesberger M M Jr, Kuhn JP. The role of computerised tomography in diseases of musculoskeletal system, ff Comp Tomo 1983; 7 (I): 85-89. 7. Jara FM, Yap A, Toledo-Pereyra LH, Magilligan DJ Jr. The role of surgery in primary osteomyelitis of the chest wall. ff Thorac Cardiovasc Surg 1979; 77 (I): 147-15o. 8. Meadows JA, Staats BA, Pairolero PC, Rodarte Jr, Arnold PG. Effects of resection of the sternum and manubrium in conjunction with muscle transposition on pulmonary function. Mayo Clin Proc 1985; 6o (9): 604-609. * Address correspondence to Dr N. N. Damani