Primary cutaneous actinomycosis of the lumbar region: An uncommon organism in an uncommon site: A Case Report

Primary cutaneous actinomycosis is a rare entity that is mostly associated with trauma. It is caused by Actinomyces species and presents with multiple discharging skin nodules. Its clinical features can resemble other disease conditions including neoplasms. Misdiagnosis can cause delay in treatment with subsequent disease progression and physical deformity.
Here we present the case of an 87-year-old female who presented with multiple discharging skin nodules in the lumbar region. She did not give a history of trauma or features suggestive of actinomycosis at any other site. Imaging and aerobic culture were negative. Anaerobic culture was not done. Biopsy of the lesion revealed Actinomyces colonies in the dermis. Subsequently a diagnosis of primary cutaneous actinomycosis was made.
This case report underpins the importance of considering actinomycosis in the differential diagnosis of patients presenting with discharging skin nodules, in uncommon sites, even in the absence of a typical clinical history.