A population study of the reported incidence of native joint septic arthritis in the United Kingdom between 1998 and 2013

Objectives. Septic arthritis is a life-threatening condition with mortality rates of 10-15%. Previous studies in other countries have shown the incidence of septic arthritis may be changing. Our aim was investigate the incidence and pattern of native joint septic arthritis in the UK. Methods. We performed an analysis using Hospital Episode Statistics to investigate the reported incidence of septic arthritis in the UK between 1998 and 2013. Results. A total of 54 532 cases of septic arthritis were reported via Hospital Episode Statistics during the timeframe studied. There has been a 43% increase in the reported incidence of septic arthritis, with rates rising from 5.5/100 000 in 1998 to 7.8/100 000 in 2013. The rate increased most rapidly in those >75 years of age (15/100 000 in 1998 and 31/100 000 in 2013). Staphylococcal species were the most frequently reported, followed by Streptococcus. Pneumococcus rates were relatively stable, with the exception of a 7-fold spike in reported incidence in 2011. Discussion. This large population-based study demonstrates that the incidence of septic arthritis is increasing in the UK. Rates are increasing most rapidly in the >75 years age group, which is likely the result of increasing co-morbidities. The clustering of pneumococcal cases has potential public health implications.