Salmonella septic arthritis in systemic lupus erythematosus and other systemic diseases

Salmonella infection is an important problem in immunocompromised patients. The synovium is a particular metastatic focus of Salmonella infection and can result in many disabilities of life. Systemic lupus erythematosus (SLE) patients were highly susceptible to Salmonella infection. In the past 6 years, 41 patients with Salmonella septic arthritis have been treated in our hospital. Eleven patients had an underlying systemic disease of SLE which presented with a distinctive clinical course. Alcoholic liver disease (six cases) was another common underlying systemic disease. The most frequent predisposing articular factor was avascular necrosis (16 cases): The hip joint was the most commonly involved site. Salmonella group B was the most common serotype (30/41). Seventy-three per cent (8/11) of the SLE group had involvement of two or more joints compared with only three out of 30 patients in the non-SLE group. The sex differentiation shows a predominance of young females (10/11) in the SLE group and middle-aged males in the non- SLE group. Moreover, in the SLE group, all 11 patients shared the risk of lupus nephritis and steroid use. Ten patients had Salmonella group B bacteraemia and five had urinary tract infections simultaneously. In the non- SLE group, there were 10 patients with a history of steroid use, three with antecedent enteritis, 12 with bacteraemia, and three with necrotising fasciitis. Seven patients in each of the groups had a recurrent course. However, three patients in the non-SLE group had died during the episode of septic arthritis.