Objective. The aim of the present study was to ascertain the degree of occurrence of tuberculous infection in patients presenting with low back pain (LBP). Methods. Forty consecutive patients seeking primary medical attention for the main symptom of LBP and presenting to the Rheumatology Outpatient Clinic of our institution from January 2004 to June 2005, were recruited in this cohort study. All patients were thoroughly interrogated (occupational, trauma, infection, diabetes mellitus and medication history), subjected to a rigorous clinical examination and a battery of investigations Results. Twelve of the 40 patients (33%) proved to have spinal TB as the cause of backache. Eight of these patients were above the age of 65. Five of the 12 patients with spinal TB also had concomitant osteoarthritic changes of the spine and two patients had concomitant disc prolapse. Eleven of the 12 patients with spinal TB had a completely normal chest X-ray and in 10 of these patients the plain X-ray of the lumbosacral region failed to show any significant lesion. In all 12 patients, sputum analysis failed to reveal acid-fast bacilli. Conclusions. The findings of this study indicate that TB is a common cause of LBP that is liable to be overlooked in the differential diagnosis of LBP. Furthermore, evidence of concurrent active intrathoracic TB may be lacking and consequently a high level of suspicion is required. The need for prompt diagnosis and treatment of skeletal TB is of utmost importance to prevent serious bone and joint destruction and severe neurological sequelae. A reliable imaging modality for diagnosing spinal TB seems to be magnetic resonance imaging.