Septic arthritis of the acromioclavicular joint due to Streptococcus agalactiae. Case report

Septic arthritis of the acromioclavicular joint is a rare entity: only 30 cases have been reported in the literature since 1985. We present the case of a 53-year-old diabetic male, with septic arthritis of one acromioclavicular joint due to Streptococcus agalactiae. Current condition characterised by neck pain, limited movement of the right shoulder; hyperthermia, hyperaemia and increased volume in the acromioclavicular joint. Upon physical examination, increased volume was found from the proximal third of the deltoid to the middle third of the clavicle, pain on palpation, localised hyperthermia, limited range of motion. X-ray with enlargement of soft tissues, presence of subcutaneous gas and increased space in the acromioclavicular joint compared with the contralateral. Ceftriaxone and Clindamycin were administered at therapeutic doses and an acromioclavicular arthrotomy was performed, obtaining 10 ml of purulent material from the sub-deltoid and 2 ml from the joint. Five days later, Streptococcus agalactiae was reported. Clinical improvement was observed and it was decided to discharge the patient.