Molecular identification of human tuberculosis in recent and historic bone tissue samples: The role of molecular techniques for the study of historic tuberculosis

We describe the molecular identification of the M. tuberculosis complex DNA in bone tissue samples from recent and historic populations. In a first set, archival paraffin material from vertebral bodies of 12 recent cases with clinically/microbiologically proven tuberculosis was compared to 12 further cases without tuberculosis. While eight TB cases revealed a specific mycobacterial amplification product, none of the controls was positive. Interestingly, one case with tuberculous sepsis (Landouzy sepsis), five cases with tuberculous spread beyond the primarily affected organ (i.e., lymph node or miliar involvement), and also two of six cases with restricted pulmonary tuberculosis reacted positively in the vertebral specimens. This indicates that a molecular analysis can detect mycobacteria even in unremarkable bone tissue, proving that organ tuberculosis is present. In addition, the extent of spread is of high significance for the frequency of positive reactions. In addition, we investigated a series of vertebral samples coming from an Egyptian population of the necropolis of Thebes-West dating to approximately 1450-500 BC. In this group of 36 cases, three of five cases with typical macromorphological signs for tuberculous spondylitis, 2 of 12 cases with nonspecific alterations, and 2 of 19 cases without macroscopic pathology revealed a specific amplicon of the M. tuberculosis complex. This suggests a significant frequency of infected people in that ancient population. Finally, a fourth group of 51 long bone samples with pathological alterations coming form a southern German ossuary (between AD 14001800) was investigated, and 10 cases were positive for the M. tuberculosis complex. These studies of historic material clearly support the notion that tuberculous infections can be unequivocally identified by molecular techniques. The relatively high frequency of ancient bacterial DNA amplifications in unremarkable bone is well-explained by our analysis of the recent material. Our data form an important basis for the investigation of tuberculosis frequency and spread in historic periods. (C) 2004 Wiley-Liss, Inc.