Treponemal infection in Peru's Early Colonial period: A case of complex lesion patterning and unusual funerary treatment

•This case study describes a probable case of tertiary treponemal disease from early Colonial Peru.•Diagnosis is also examined in terms of the highly informal disposal of this body.•This study raises new questions about Andean treponematosis.•This study underscores synergisms between paleopathology and mortuary archaeology.

This study describes a series of skeletal lesions observed in a mid 16th century individual of an old adult female from the Early Colonial Period of northern coastal Peru. This fragmented skeleton revealed evidence of complex, active, and systemic chronic infection that included multiple pathological foci on the cranial vault, extensive pathological new bone formation in both arms, the sternum, ribs, left scapula, clavicles, femora, and fibulae, which was paralleled by extensive endosteal obliteration of affected long bone medullary cavities. Differential diagnosis included hematogenous osteomyelitis, Paget's disease, fluorosis, melorheostosis, endosteal hyperostosis, and hypertrophic osteoarthropathy. Simultaneous periosteal and endosteal bone deposition of the clavicles, in addition to patterns of florid bone deposition on long bones and superficial cavitation, point most directly to treponemal disease. Co-morbidity with a non-specified respiratory disease and well-healed fractures of the tibiae are also considered. We also relate this person's illness to the highly informal disposal of their body to underscore how social perceptions of disease may have shaped this unusual and informal funerary ritual. Ultimately, this research cautions against overly “tibia-centric” thinking regarding treponemal syndromes, raises questions regarding the history and nature of treponemal disease in Peru, and highlights cross-disciplinary connections between paleopathology and mortuary archaeology.