Histopathological analysis revealed that Mycobacterium abscessus proliferates in the fat bodies of silkworms.

Mycobacterium abscessus causes chronic skin infections, lung diseases, and systemic or disseminated infections. Although a silkworm infection model with M. abscessus has been established, pathological analysis of the infected silkworms has not been performed. In this study, we performed hematoxylin-eosin and Ziehl-Neelsen staining of silkworms infected with M. abscessus. Four days after infection with M. abscessus, M. abscessus accumulation was observed in the fat bodies of silkworms. The number of viable M. abscessus cells in the fat bodies of the infected silkworms increased over time. These results suggest that M. abscessus proliferates in the fat bodies of the infected silkworms.