Otitis media and mastoiditis in temporal bones of prehistoric Chilean populations. A paleopathological and paleoepidemiological study

Probing Immune-Mediated Clearance of Acute Middle Ear Infection in Mice

Acute otitis media (AOM) is commonly caused by bacterial pathobionts of the nasopharynx that ascend the Eustachian tube to cause disease in the middle ears. To model and study the various complexities of AOM, common human otopathogens are injected directly into the middle ear bullae of rodents or are delivered with viral co-infections which contribute to the access to the middle ears in complex and partially understood ways. Here, we present the novel observation that Bordetella bronchiseptica, a well-characterized respiratory commensal/pathogen of mice, also efficiently ascends their Eustachian tubes to colonize their middle ears, providing a flexible mouse model to study naturally occurring AOM. Mice lacking T and/or B cells failed to resolve infections, highlighting the cooperative role of both in clearing middle ear infection. Adoptively transferred antibodies provided complete protection to the lungs but only partially protected the middle ears, highlighting the differences between respiratory and otoimmunology. We present this as a novel experimental system that can capitalize on the strengths of the mouse model to dissect the molecular mechanisms involved in the generation and function of immunity within the middle ear.

Osteolytic lesions on the os petrosum of a Bronze Age individual from La Llana cave (Northern Spain) compatible with a possible case of otitis media. A multifaceted methodological approach

OBJECTIVE

To encourage the use of different methodological approaches for the identification of paleopathological lesions and to evaluate osteolytic lesions found on a temporal bone from La Llana cave (Spain).

MATERIALS

Cranial remains recovered from from La Llana cave (Spain) dated to the Bronze Age, 3300 ± 25 BP (1631-1509 cal BC).

METHODS

The cranium underwent macroscopic, microscopic and computed tomography scan examinations.

RESULTS

The Tegmen tympani of the left temporal bone is present but is missing on the right. Both cochleae are intact. Both the right and left temporal bones display osteolytic lesions, with the left Tegmen tympani displaying deep and profuse pits on the endocranial surface, exposing the ear channel.

CONCLUSIONS

The lesions are compatible with otitis media (atticitis). By using different methods of analysis, the presence and effects of infection were identified.

SIGNIFICANCE

This systematically described case contributes to our understanding of disease in the past and describes otitis-related lesions in archeological contexts for comparative purposes.

LIMITATIONS

The fragmentary and damaged cranial remains rendered evaluation difficult and diagnosis tentative.

SUGGESTIONS FOR FURTHER RESEARCH

The use of different approaches to diagnose otitis media in archeological skeletal collections is recommended to improve the knowledge of health status and lifestyle of past populations.