Osteomyelitis in a Paleozoic reptile: ancient evidence for bacterial infection and its evolutionary significance

Abstract

We report on dental and mandibular pathology in Labidosaurus hamatus, a 275 million-year-old terrestrial reptile from North America and associate it with bacterial infection in an organism that is characterized by reduced tooth replacement. Analysis of the surface and internal mandibular structure using mechanical and CT-scanning techniques permits the reconstruction of events that led to the pathology and the possible death of the individual. The infection probably occurred as a result of prolonged exposure of the dental pulp cavity to oral bacteria, and this exposure was caused by injury to the tooth in an animal that is characterized by reduced tooth replacement cycles. In these early reptiles, the reduction in tooth replacement is an evolutionary innovation associated with strong implantation and increased oral processing. The dental abscess observed in L. hamatus, the oldest known infection in a terrestrial vertebrate, provides clear evidence of the ancient association between terrestrial vertebrates and their oral bacteria.

Tooth loss and alveolar remodeling in Sinosaurus triassicus (Dinosauria: Theropoda) from the lower jurassic strata of the Lufeng Basin, China

“…Dental abscesses, such as those reported in an unidentified hadrosaurid jaw [27] and in the captorhinid Labidosaurus [28], have yet to be identified in theropods. Abscesses form as a result of deep bacterial infections, resulting in osseous erosions associated with alveolar bone destruction and tooth loss.…”

New Antibiotics in the Therapy of Osteomyelitis

“…Histological samples as well as up to 5 soft-tissue samples for culture should be obtained [10] . Antibiotic prophylaxis given at the induction of anesthesia does not interfere with intraoperative sampling cultures [1] . If image-guided needle biopsy is obtained, at least 2 mL of fluid should be aspirated to improve sensitivity [24] .…”

“…Osteomyelitis is a disease that has been known for centuries and has been detected in fossils that deceased 275 million years ago [1] , due to possibly the same pathogens as today. Nevertheless, its treatment is still under ongoing discussion.…”

Canadian Society of Vertebrate Palaeontology 2017 Meeting Abstracts

“…Most described paleopathologies can be attributed to trauma of the limbs and ribs, with little documented evidence of disease in early Permian material (Reisz et al 2011). The Doles Brothers limestone quarry near Richards Spur, Oklahoma, USA, is unique in having the richest collection of tetrapod fauna in the world (Macdougall and Reisz 2012), as such it represents a fertile faunal assemblage from which to sample pathologies.…”