1559. Methicillin Susceptible Staphylococcus aureus Is The Predominant Organism In Septic Bursitis With The Majority Involving The Olecranon Bursa: A Study Of 61 Cases

BACKGROUND: Bursae are fluid filled structures between mobile parts of the musculoskeletal system to reduce friction between surfaces by lubrication. The most frequently infected are the olecranon and prepatellar bursae. In reported studies there is male preponderance, a relationship to occupational or recreational activities, a mean age of about 50 years and the most frequent organism being Staphylococcus aureus. The frequency of methicillin resistance is not well documented. METHODS: We analyzed approximately 7000 Staphylococcus aureus isolates reported by the laboratory over a 3-year period in 10 of our network hospitals, 9 in Eastern Pennsylvania and one in adjacent Warren County, New Jersey and found 61 cases of S. aureus septic bursitis. RESULTS: Only 13/61 (21.3%) were caused by methicillin resistant S. aureus (MRSA), 8 olecranon (61.5%), 4 prepatellar (30.8%) and one subacromial (7.7%). Only one in MRSA group (olecranon bursitis) was female. The mean age of MRSA cases was 58.5. Methicillin susceptible S. aureus (MSSA) predominated with 34/48 (70.8%) olecranon bursitis (28M/6F), 11/48 (22.9%) prepatellar bursitis (10M/1F) and 3/48 (6.3%) sub acromial bursitis (1M/2F) with a mean age of 61.9. Overall (MRSA +MSSA), 51/61 (83.6%) were male and 10/61 (16.4%) were female. The olecranon bursa was involved in 42/61 (68.9%), prepatellar bursa 15/54 (24.6%) and subacromial bursa 4/54 (6.6%). The mean age for the entire group was 61.2 with the youngest 23 and the oldest 93. The occupational history was recorded only in a few patients e.g. roofer, floor worker, construction worker. Three in the MSSA group had bacteremia (2 subacromial bursitis and 1 olecranon bursitis). There was 1 death from gram negative sepsis which was unrelated. The majority were successfully treated with a combination of drainage and antibiotics. CONCLUSION: In summary, our study shows a predominance of olecranon bursitis, with a higher incidence in males and majority caused by MSSA. The mean age around 61 was higher than the mean age in prior reports around 50 years. Elbows and knees accounted for 57/61 (93%) cases of septic bursitis. Avoidance of activities involving friction or repeated trauma to elbows and knees should help prevention of septic bursitis. As far as we are aware, this is the largest series of septic bursitis reported. DISCLOSURES: All Authors: No reported disclosures