Chronic granulomatous bacterial infections – actinomycosis, nocardiosis and botryomycosis: a histopathological approach for diagnostics

Abstract

Chronic filamentous and non-filamentous bacterial granulomatous diseases, including actinomycosis, nocardiosis, and botryomycosis, are uncommon and rarely fatal diseases. Diagnosis is supported by microbiological and molecular evaluation; however, histological diagnosis enables precise conclusions to be reached, thereby facilitating the initiation of appropriate and timely treatment. A common tissue reaction seen in the three clinical entities under review is the Splendore-Hoeppli phenomenon. This reaction is characterized by the presence of radiant, eosinophilic material in the form of an asteroid or mace around infectious and non-infectious agents. The objective of this article is to offer a comprehensive yet concise approach to the histo-morphological evaluation of chronic filamentous and non-filamentous bacterial granulomatous diseases.