Osteoarticular tuberculosis in Tehran, Iran: a 2-year study.

Osteoarticular tuberculosis (TB) accounts for 1-5% of all TB cases and 10-18% of those with extrapulmonary infection. Diagnosis is difficult, because the lungs are rarely involved and there are no specific signs or symptoms. The purpose of this study was to assess the frequency and clinical and laboratory findings in osteoarticular TB in two referral hospitals in Tehran, Iran. The hospital dataset of patients admitted with osteoarticular TB during 2003-2005 was reviewed. Patients' demographic data, clinical presentation and radiological and pathological findings were analysed. Weight loss (50%), fever (36%) and night sweats (38.5%) were the most common constitutional symptoms. Knee, ankle, hip and shoulder joints were the most frequent sites for TB arthritis. In osteomyelitis, long and short bones were equally affected. In TB spondylitis, the lumbar (22.7%) and thoracic (50%) vertebrae were the most commonly involved sites. The most frequently reported complications were sphincter disorder (39.1%), paraplegia (28.9%) and kyphosis (19.3%). TB osteomyelitis must always be borne in mind in countries where TB has high prevalence.