Spina bifida, the normal, the pathological and the in-between: first evidence from a forensic osteological collection.

Spina bifida (SB), a rare congenital disorder, is often mentioned as an individualizing factor in Forensic Anthropology. A lack of empirical data regarding SB is noticed in the scientific literature. Moreover, within the scope of anthropological research on SB disparities in terminology, classification systems, and methodological approaches result in incomparable results. The wide range (1,2%-50%) of "spina bifida occulta" reported prevalences is a good example. This research aims to analyze and debate the standard diagnostic criteria of SB on human skeletal remains, and attempts to elaborate on an universal system, premised on the distinction between SB as a pathology, and cleft neural arch (CNA) as an anatomical variant, according to Barnes (1994, p. 360 [1). A study-base of 209 individuals (88 males; 121 females; 44-99 years old) from the 21st Century Identified Skeletal Collection from the University of Coimbra (CEI/XXI) was macroscopically analyzed, focusing on the sacrum and remaining vertebrae. Four individuals presented complete posterior opening of the sacral canal (2,6%[4/156]). The observed bone changes, combined with the analysis of the entire skeleton, indicate that CNA, rather than SB linked to a neural tube defect, is the most reliable explanation for these cases. Overall, CNA was observed on 11 skeletons (7.05% of 156). The viability and applicability of the developed methodology for the identification of SB/CNA in forensic and/or osteological contexts are discussed, as well as the possibility of a lower prevalence of SB occulta, in the general population, than speculated before. HIGHLIGHTS: • Spina bifida has been studied so far under different methodologies, classification systems and nomenclature, leading to unstandardized and incomparable data. • Spina bifida as a pathological manifestation of a neural tube defect, as opposed to cleft neural arch as a simple form of skeletal variation. • Both spina bifida and complete sacral cleft fit the criteria of an individualizing trait in Forensic Anthropology.

Mycobacterium leprae diversity and population dynamics in medieval Europe from novel ancient genomes.

BACKGROUND: Hansen's disease (leprosy), widespread in medieval Europe, is today mainly prevalent in tropical and subtropical regions with around 200,000 new cases reported annually. Despite its long history and appearance in historical records, its origins and past dissemination patterns are still widely unknown. Applying ancient DNA approaches to its major causative agent, Mycobacterium leprae, can significantly improve our understanding of the disease's complex history. Previous studies have identified a high genetic continuity of the pathogen over the last 1500 years and the existence of at least four M. leprae lineages in some parts of Europe since the Early Medieval period. RESULTS: Here, we reconstructed 19 ancient M. leprae genomes to further investigate M. leprae's genetic variation in Europe, with a dedicated focus on bacterial genomes from previously unstudied regions (Belarus, Iberia, Russia, Scotland), from multiple sites in a single region (Cambridgeshire, England), and from two Iberian leprosaria. Overall, our data confirm the existence of similar phylogeographic patterns across Europe, including high diversity in leprosaria. Further, we identified a new genotype in Belarus. By doubling the number of complete ancient M. leprae genomes, our results improve our knowledge of the past phylogeography of M. leprae and reveal a particularly high M. leprae diversity in European medieval leprosaria. CONCLUSIONS: Our findings allow us to detect similar patterns of strain diversity across Europe with branch 3 as the most common branch and the leprosaria as centers for high diversity. The higher resolution of our phylogeny tree also refined our understanding of the interspecies transfer between red squirrels and humans pointing to a late antique/early medieval transmission. Furthermore, with our new estimates on the past population diversity of M. leprae, we gained first insights into the disease's global history in relation to major historic events such as the Roman expansion or the beginning of the regular transatlantic long distance trade. In summary, our findings highlight how studying ancient M. leprae genomes worldwide improves our understanding of leprosy's global history and can contribute to current models of M. leprae's worldwide dissemination, including interspecies transmissions.

Time burnt away: The impact of heat-induced changes on skeletal age-at-death diagnostic features.

This paper investigates the established notion that bone calcination has a major impact on age estimation while low-intensity burns have a mere negligible impact. Few systematic researches have been carried out so far about this topic so the true impact of heat-induced changes on diagnostic age features is mostly unknown. The agreement between pre-burning and post-burning observations of age features was investigated on 51 human skeletons (22 males and 29 females with ages-at-death ranging from 61 to 93 years old) subjected to experimental burns. These skeletons belong to the 21st Century Identified Skeletal Collection housed at the Laboratory of Forensic Anthropology of the Department of Life Sciences, University of Coimbra, Portugal. The Suchey-Brooks method based on the pubic symphysis and the method developed on the auricular surface by Buckberry and Chamberlain (2002) were scrutinized. The Suchey-Brooks method provided better agreement between pre- and post-burn observations than the method from Buckberry and Chamberlain (2002). However, it became clear that heat-induced changes affected both methods regardless of heat intensity since both calcined bones and bones burnt at lower intensities often showed less than perfect agreement. Therefore, this research demonstrates that the analysis of age-at-death can be impaired in burnt bones, even those not subjected to calcination, with clear impact for forensic and archaeological investigations.

Cancers as rare diseases: Terminological, theoretical, and methodological biases.

OBJECTIVE: Was cancer a rare disease in the past? Our objective is to consider the various terminological, theoretical, and methodological biases that may affect perceptions of the rarity of cancer in the past. MATERIALS AND METHODS: We discuss relevant malignant neoplastic biomedical and paleopathological literature and evaluate skeletal data. We selected 108 archaeological sites (n = 151 cancer cases) with published malignant neoplasms and that were amenable to calculating cancer crude prevalence. Furthermore, datasets from four medieval/postmedieval Portuguese and 12 postmedieval UK sites were used to compare age-adjusted rates for metastatic bone disease and tuberculosis. RESULTS: In the literature review, mean cancer crude prevalence (1.2 %; 95 % CI = 0.96-1.4) exceeded the threshold for a rare disease (RD). Age-standardized rates of MBD and TB were not markedly different in the sites surveyed. CONCLUSIONS: Methodological, theoretical and historical factors contribute to assumptions that cancers were rare diseases. The assumption that cancers are extremely rare in the paleopathological literature was not fully supported. Cancer is a heterogeneous concept, and it is important to view it as such. If a disease is considered rare, we may fail to recognize it or dismiss it as unimportant in the past. SIGNIFICANCE: We present a re-evaluation of the idea that cancer is a rare disease. We present a more nuanced way of comparing rates of pathological conditions in archaeological contexts. LIMITATIONS: Variation in the amount of useable information in published literature on malignant neoplasms. SUGGESTIONS FOR FURTHER RESEARCH: More large-scale studies of cancer in the past alongside comparative studies of cancer prevalence with other assumed rare diseases.

The first probable evidence of leprosy in a male individual (17th-19th century AD) unearthed in Northern Portugal (Travanca, Santa Maria da Feira).

OBJECTIVE: This study describes the first evidence of a probable paleopathological case of leprosy from northern Portugal. MATERIALS: An adult male, skeleton 403, exhumed from the Christian cemetery associated with the church dedicated to Saint Mamede (Travanca, Santa Maria da Feira), dated from the 17th-19th century AD. METHODS: Standard bioarchaeological methods were used for sex and age-at-death determinations, and leprosy-related bone lesions were identified through macroscopic analysis guided by paleopathological diagnostic criteria. RESULTS: The macroscopic observation revealed probable leprosy-related skeletal lesions, namely tenuous rhinomaxillary changes, bilateral proliferative periosteal reactions on the tibiae and fibulae, as well as concentric atrophy, acro-osteolysis and ankyloses of foot bones. CONCLUSIONS: Skeleton 403 represents a probable case of leprosy according to the nature and distribution pattern of bony lesions observed. SIGNIFICANCE: This finding fills an important gap in the history of leprosy in Portugal. Although historical sources show that the majority of leprosaria were located in the northern part of the country, suggesting that leprosy was more prevalent in this area of Portugal in the past, no paleopathological evidence of this disease was reported for this region to date. Furthermore, the inhumation of a leprosy sufferer in a 17th-19th century AD Christian parish cemetery is deeply imbued with social meaning. SUGGESTION FOR FUTURE RESEARCH: The future detailed study of the remaining skeletons unearthed from the cemetery of the Church of São Mamede will hopefully reveal further osteological evidence of leprosy in addition to the application of ancient DNA analysis to confirm the presence of the pathogen of this disease. Also, further documentary research is needed in order to expand appreciation of the epidemiological and social impact of leprosy in the 17th-19th century AD Portugal.

Differential diagnosis of a diffuse sclerosis in an identified male skull (early 20th century Coimbra, Portugal): A multimethodological approach for the identification of osteosclerotic dysplasias in skeletonized individuals.

OBJECTIVE: This work aims to discuss the difficulties in diagnosing osteosclerotic changes in skeletonized individuals and to raise awareness of osteosclerotic dysplasias as a group of rare ancient diseases. MATERIALS: The skull of a 62-year-old male individual from the International Exchange Skull Collection, curated by the University of Coimbra, who died in 1928 presenting albuminous nephritis (Bright disease)/uraemia as the registered cause of death. METHODS: The skull was macroscopically and radiologically examined and bone elemental analysis was investigated. The genealogy and medical records of the individual were also searched. RESULTS: The lesions are in accordance with an osteosclerotic process possibly pointing to osteosclerosis, osteosclerotic metaphyseal dysplasia, or dysosteosclerosis, but osteoclasia with hyperphosphatasia, endosteal hyperostosis, sclerosteosis, or osteopathia striata with cranial sclerosis cannot be ruled out. CONCLUSIONS: Representativeness of the skeleton is a crucial feature in diagnosing rare diseases and, to avoid a misdiagnosis, the final diagnosis should include a group of diseases rather than a definite disease. SIGNIFICANCE: Difficulties in diagnosing rare diseases are discussed and best approaches in the study osteosclerotic dysplasias in skeletonized individuals are offered in the light of current clinical knowledge. LIMITATIONS: The absence of the postcranial skeleton and of pathognomonic lesions associated with osteosclerotic dysplasias limits diagnosis. Although rare diseases often have a genetic basis, specific genetic testing for the diagnosis of rare diseases in paleopathological cases are not yet available. SUGGESTIONS FOR FURTHER RESEARCH: Future genetic studies might help narrow down the diagnosis.

Trends in mortality from pulmonary tuberculosis before and after antibiotics in the Portuguese sanatorium Carlos Vasconcelos Porto (1918-1991): Archival evidence and its paleopathological relevance.

The comparative study of patients' profiles and outcomes from pulmonary tuberculosis (TB), before and after the discovery of antibiotic therapy, using sanatoria archives is an unexplored approach in paleopathology. Although higher mortality rates are assumed before chemotherapy, scarce information exists regarding the disease's duration in institutionalized patients and to what extent tuberculous sufferers lived enough to develop skeletal lesions. To fill this gap, 315 clinical files from the former male Sanatorium Carlos Vasconcelos Porto, located in São Brás de Alportel, Portugal, were studied. Two periods of hospitalization were considered: 1931-1944 (n = 128, Group 1) and 1955-1961 (n = 187, Group 2). The average duration of hospitalization (350.3 days for Group 1 and 371.8 for Group 2) and the crude mortality (18.2% and 11.2%, respectively in Groups 1 and 2) did not differ significantly between groups. However, Cox's regression revealed significant differences between survival curves, after adjusting for age at admission (14-74 years old), with pre-chemotherapy patients presenting a higher risk of dying during hospitalization (p = 0.037, hazard ratio = 1.94, IC95% = 1.03-3.63). This study also confirms poorer prognoses for pulmonary tuberculosis sufferers hospitalized in sanatoria before antibiotics and reveals that a significant number of patients survived enough time to develop bone lesions.