Chronic inflammatory polyarthritides in a select population of young men. A prospective study.

Twenty young servicemen suffering from chronic inflammatory polyarthritides (CIP) were studied. While rheumatoid arthritis (RA) was the final diagnosis in 15 patients, the arthritis remained 'unclassifiable' in the rest. An acute onset of asymmetric deforming arthritis, dominant in the lower limbs, was the usual pattern. Sacroiliitis and enthesopathy were uncommon. Extra-articular features were sparse and sub-cutaneous nodules absent. Rheumatoid factor was present in 86.7% of RA patients. Radiologic erosions were evident in 73.3% RA patients. Arthritis robustus variant of RA was diagnosed in 4 patients. HLA B27 was present in 45.5% of RA patients in this atypical setting. An overlap of RA and seronegative spondarthritides was considered probable in 3 patients.