Characteristics of patients with definite septic arthritis at Hamad General Hospital, Qatar: a hospital-based study from 2006 to 2011

The aim of this retrospective study was to determine the epidemiological and clinical characteristics, coexisting conditions, causative organisms, and outcomes of all adult patients 15 years of age or older who had definite septic arthritis at Hamad General Hospital, Qatar, from 2006 to 2011. During this period, 56 patients were diagnosed with septic arthritis (mean age ± SD, 49.0 ± 16.6 years). In 53 of 56 (94.6 %) patients, arthritis was diagnosed in a single joint, while polyarthritis was diagnosed in 3 of 56 (5.4 %) patients; the most commonly involved joint was the knee (40 of 59 joints, 67.7 %). The most frequent coexisting condition was diabetes mellitus (24 of 56 patients, 42.8 %). Joint pain and restriction of movement were reported by all patients. Gram-positive bacteria accounted for 36 of all 57 (63.0 %) isolated microorganisms, and Staphylococcus aureus was the most common pathogen (20 of 57 microorganisms, 35.0 %). Three cases of tuberculous arthritis were seen. The most favored antibiotic combinations were cloxacillin/ciprofloxacin, cefazolin/ciprofloxacin, and vancomycin/ciprofloxacin. Repeated needle aspiration, open joint drainage, and arthroscopic techniques were performed in 18 (32.1 %), 22 (39.3 %), and 11 (19.6 %) of the 56 patients, respectively. The 30-day mortality was 3.6 %, and the remaining patients showed clinical improvement upon discharge. In conclusion, there was no specific sign or symptom for diagnosing septic arthritis. Isolation of bacteria from the synovial fluid confirmed the diagnosis, and S. aureus and streptococci were the most common pathogens isolated. Prompt treatment with appropriate antibiotics and synovial drainage are mandatory to improve the outcome.