Unusual spinal tuberculosis in an Avar Age skeleton (Csongrád-Felgyő, Ürmös-tanya, Hungary): A morphological and biomolecular study

Bioarchaeological and molecular evidence of tuberculosis in human skeletal remains from 18th-19th century orthodox cemeteries in Irkutsk, Eastern Siberia

In this study, we tested the skeletal human remains from the 18th - early 19th century Orthodox cemeteries in Irkutsk, Eastern Siberia, for tuberculosis-associated morphological alterations and Mycobacterium tuberculosis DNA. The morphologically studied bone collection included 591 individuals of mainly Caucasian origin. The molecular methods (IS6110-PCR and spoligotyping) suggested that at least four individuals (out of 15 TB-suspected, DNA-tested) were positive for the presence of M. tuberculosis DNA. All of them were males (3 maturus, 1 maturus senilis). Two of them date back to the second and third quarters of the 18th century, another to the last quarter of the 18th century, and the last one to the second half of the 19th century. The combined molecular analysis cautiously suggested presence of different strains and at least some of them represented not the currently predominant in Siberia Beijing genotype (M. tuberculosis East-Asian lineage) but strains of European origin. In conclusion, this study presented bioarchaeological and molecular evidence of tuberculosis in human skeletal remains from 18th-19th century Orthodox cemeteries in Irkutsk, Eastern Siberia. The samples are not M. bovis and represent human M. tuberculosis sensu stricto. Their precise phylogenetic identity is elusive but evokes the European/Russian origin of at least some isolates.

"Tuberculosis on the spot" - Discussion of a probable sternal tuberculosis from a late medieval cemetery from Hungary

Investigations of non-adult remains are particularly suitable for finding epidemic periods in past populations. This study presents a probable unique example of osseous manifestation of tuberculosis on a child's skeletal remains from medieval Hungary. Between 2009 and 2011 the Field Service for Cultural Heritage excavated the exceptional cemetery of Perkáta - Nyúli-dűlő in Hungary, with around 5000+ graves. The analysed skeleton (SNR 948) was located in the medieval (10-16th century) part of the cemetery. Besides the standard macroscopic pathological observation, we also performed radiographic analysis. The remains of the child (13-14 year-old) showed numerous skeletal lesions: the ribs have proliferative lesions (dense nodules) on the visceral surface of the shaft, lytic lesions with rounded edges occurred on the thoracic and lumbar vertebral bodies, and on the facies auricularis of the left ilium we can see pitting and new bone formation. What makes this pathological case exceptional is the significant change in the manubrium. It shows extensive osteolytic lesions, probably due to tuberculous osteomyelitis, which is a unique phenomenon in an archaeological context. This rare type of extra-spinal tuberculous osteomyelitis appears in less than 1% of cases with skeletal TB, and even less in case of children, according to modern medical literature. Although some cases of slight lesions on the manubrium have been described from an archaeological context, no such cases showing advanced lesions have been published so far. In the future, biomolecular analyses should be conducted as well, in order to confirm the presence of TB in this individual.

The association between skeletal lesions and tuberculosis diagnosis using a probabilistic approach

Sensitivity and specificity estimates for 18 skeletal lesions were generated from modern skeletons for future paleoepidemiological analyses of tuberculosis prevalence in archaeological samples. A case-control study was conducted using 480 skeletons from 20^th century American skeletal collections. One-half of the skeletons were documented tuberculosis cases (Terry Collection). The remaining age and sex-matched skeletons were controls (Bass Collection). The association between 18 candidate skeletal lesions and tuberculosis was established by comparing lesion distributions in case and control groups. Lesion indicators at six locations - visceral surface of ribs, ventral vertebral bodies, lateral part of ilium, acetabular fossa, iliac auricular surface, and ulna olecranon process - occurred significantly more often among cases than in controls, and were associated with one another. The most useful indicator proved to be a bony reaction on ventral thoracic and lumbar vertebral bodies. Its presence means a 53.3% probability of a true tuberculosis diagnosis. Because of the nature of the reference sample - 20th century American cases - sensitivity and specificity estimates will better estimate disease prevalence in archaeological samples from cultural settings where pulmonary tuberculosis predominated. The general approach of this proof-of-concept study is applicable to other diseases that occur commonly and affect bone.

The Evolutionary History, Demography, and Spread of the Mycobacterium tuberculosis Complex

With the advent of next-generation sequencing technology, the genotyping of clinical Mycobacterium tuberculosis strains went through a major breakup that dramatically improved the field of molecular epidemiology but also revolutionized our deep understanding of the M. tuberculosis complex evolutionary history. The intricate paths of the pathogen and its human host are reflected by a common geographical origin in Africa and strong biogeographical associations that largely reflect the past migration waves out of Africa. This long coevolutionary history is cardinal for our understanding of the host-pathogen dynamic, including past and ongoing demographic components, strains’ genetic background, as well as the immune system genetic architecture of the host. Coalescent- and Bayesian-based analyses allowed us to reconstruct population size changes of M. tuberculosis through time, to date the most recent common ancestor and the several phylogenetic lineages. This information will ultimately help us to understand the spread of the Beijing lineage, the rise of multidrug-resistant sublineages, or the fall of others in the light of socioeconomic events, antibiotic programs, or host population densities. If we leave the present and go through the looking glass, thanks to our ability to handle small degraded molecules combined with targeted capture, paleomicrobiology covering the Pleistocene era will possibly unravel lineage replacements, dig out extinct ones, and eventually ask for major revisions of the current model.