Tuberculosis has been with human kind for a very long time; suggestive spinal changes have been described in Neolithic man,¹ while clear evidence of tuberculous bone lesions have been found in mummified remains from Egypt, dating back to 3400 BC. Hippocrates (460–377 BC) introduced the ancient Greek term for tuberculosis, phthisis, which is similar in meaning to the Latin word consumere, better known as consumption.² Tuberculosis was so prevalent in the British Isles in the 17th century that it caused approximately 20% of all deaths, and John Bunyan referred to it in 1680 as “The captain of all these men of death”.²

Since then the prevalence of tuberculosis has decreased substantially in the developed world, but it remains a major cause of morbidity and death in poor countries. The modern world is an ever shrinking place and the “global village” will truly become a reality during the 21st century. Therefore, tuberculosis remains an important public health challenge for us all, as evidenced by the global tuberculosis emergency declared by the World Health Organization in 1993. In high burden settings the main aim is to contain the epidemic; consequently, childhood tuberculosis receives little public health emphasis because children rarely transmit the disease and contribute little to the maintenance of the tuberculosis epidemic. However, children do constitute a significant proportion of the tuberculosis caseload,^3,4 and experience considerable tuberculosis related morbidity and mortality,⁵ particularly in areas where tuberculosis is endemic.

AETIOLOGY

Robert Koch (1843–1910) identified tuberculosis as an infectious disease caused by Mycobacterium tuberculosis. The diagnostic techniques pioneered by Koch, such as sputum smear microscopy and culture, have remained virtually unchanged during the past century. Although M tuberculosis was identified as the causative organism, it was soon discovered that infection with this organism, as indicated …