The initial symptoms of connective tissue disease sometimes present as arthritis of the shoulder. We experienced a case of seronegative spondyloarthropathy(SpA) starting from the shoulder. It was difficult to distinguish infection and connective tissue disease due to the similar clinical presentation.
A 44-year-old man was admitted with the complaint of persistant left shoulder pain with a duration of four months. Physical examination revealed motion pain and morning pain. The leukocyte count was 6700/μl and CRP 3.86 mg/dl. MRI showed hydroarthrosis with synovial proliferation. Arthroscopic synovectomy showed nonspecific synovial proliferation. Pathological findings of the synovium demonstrated granulomatous change with neutrophil invasion, suggesting purulent synovitis. Cultivation surveys showed negative findings. Thenceforth he started to complain of pain in the contralateral shoulder and bilateral ankles. We suspected the cause to be connective tissue disease at first, but serological examinations of RF, ANA and anti-CCP Ab were all negative. He was treated with antimicrobials for six weeks, but symptoms persisted and laboratory data did not improve. Therefore, after ruling out the possibility of infection, we diagnosed SpA. After introducing Azulfidin, his clinical course and inflammatory signs showed a reduction.
The initial symptoms of connective tissue disease sometimes present as arthritis of the shoulder. In some cases, it is difficult to distinguish infection and connective tissue disease, due to the similar clinical presentation. Treatment with immunosuppressive drug is contraindicated for infection. We believe that it is important to follow the clinical course and rule out infection first in such cases.
