Septic arthritis due to Neisseria gonorrhoea in Western Australia.

ABSTRACT

BACKGROUND: A high prevalence of gonococcal infections has been reported from remote parts of Western Australia, but the occurrence of disseminated infection leading to arthritis has not been studied. AIMS: To investigate the frequency, risk factors and long-term outcome of gonococcal arthritis (GA) in Western Australia (WA). METHODS: A population-based data linkage study of patients with a hospital-based diagnosis of GA in WA between 1990 and 2014. Demographics, standardised incidence rates per million and comorbidity accrued before (lookback 186 months, interquartile range (IQR) 86-267) and after the index hospital contact for GA (follow up 100 months, IQR 60-209) are presented as frequency (%), median (IQR) or rates /1000 months. RESULTS: In total, 98 patients were diagnosed with GA. The annual incidence of GA increased from 1.35 to 2.10 per million between 1990 and 2014, but the rate of GA complicating all gonococcal infections was stable around 0.25%. Female patients with GA (54%; n = 53/98) were younger (24 vs 38 years) and more frequently identified as indigenous (88% vs 49%) than male patients (46%; n = 45/98; P = 0.002). Female patients had higher rates of prior infections (15.5 vs 8.1 per 1000 months; P = 0.002) and diabetes mellitus (15.9% vs 2.5%; P = 0.03) and a longer hospital stay (10 vs 8 days; P = 0.02). GA recurrence rate during follow up was low (2%), but a broad range of comorbidities developed contributing to a 14% crude death rate. CONCLUSIONS: GA stably complicates 0.25% of gonococcal infections in WA with young indigenous females and middle-aged non-indigenous males most affected. Prior infectious disease and diabetes mellitus are potential risk factors for GA in females. GA recurs rarely, but its development reflects a high risk of morbidity and mortality over the following 10 years.