SUMMARY The clinical features of 21 episodes of skeletal brucellosis in 17 Iraqi patients are reported. Six had monarthritis of a large joint, six had spondylitis, and five had spondarthritis. Brucellosis remains a major health problem in Iraq. The disease is transmitted to man through the ingestion of unpasteurised milk or milk products but can also be acquired through physical contact.Key words: Brucella abortus, monarthritis, spondylitis, spondarthritis. Patients and methods ResultsSeventeen consecutive patients attending our rheumatology clinic with skeletal manifestations considered to be due to brucellosis were studied. In addition to obtaining a history, physical examination, and x rays, the following investigations were performed: haemoglobin and leucocyte count, erythrocyte sedimentation rate (ESR), urine examination, latex fixation test for rheumatoid factor, antistreptolysin 0 titre, antinuclear factor, lupus erythematosus cell preparation, C reactive protein, serum uric acid, rose bengal test using a concentrated suspension of Brucella abortus (Weybridge strain) stained with rose bengal (BioMerieux), and an agglutination test with Brucella abortus antigen (Burroughs-Wellcome). HLA typing was done using the microlymphocytotoxicity technique only for the young patients in the spondylitic and spondarthritic groups. A blood culture for brucella was carried out in 12 patients and synovial fluid culture in three. A tuberculin test was done only in one patient with spondylitis. All cases were followed up for one year. In cases of relapse the ESR, leucocyte count, rose bengal and brucella agglutination tests were performed. The diagnosis of brucellosis was made on the basis of suggestive history in association with the finding of a positive rose bengal screening test and a positive agglutination titre (3,>1/320).