Kingella kingae causing septic arthritis in Felty's syndrome

A case of septic arthritis of the elbow caused by Kingella kingae, a Gram-negative bacillus, is described. The patient had long-standing, severe rheumatoid arthritis and Felty's syndrome. This appears to be the first report from the United Kingdom of Kingella kingae as the aetiological agent of septic arthritis.