Actinomycosis Causing Recurrent Perianal Fistulae

Actinomycosis is a rare but easily curable infection that should be considered in the differential diagnosis of perianal fistulizing disease. We present the case of a 26-year-old woman with complex perianal fistulae, including trans-sphincteric and suprasphincteric fistulous tracts and a rectovaginal fistula, requiring multiple abscess drainages, seton placement, and antibiotic courses, with little improvement. After extensive investigation, Actinomyces spp. was identified in anal cytology. The patient underwent a 6-week course of intravenous penicillin followed by oral amoxicillin, with remarkable improvement. This case illustrates the importance of pursuing less common diagnoses in refractory complex perianal disease, such as actinomycosis. info:eu-repo/semantics/publishedVersion