Diagnosis and Management of a Cryptoglandular Actinomycotic Fistula-in-Ano: An Update on 7 New Cases and a Review of the Literature

Abstract

Purpose: Primary anal actinomycosis of cryptoglandular origin, a rare cause of anal suppurative disease, requires specific management to be cured. The aims of this retrospective study were to describe clinical, morphological, and microbiological features of this entity and to evaluate management practices for new cases observed since 2001.

Methods: This was a retrospective case series conducted at the Diaconesses-Croix Saint-Simon Hospital in Paris.

Results: From January 2001 to July 2016, 7 patients, 6 males and 1 female (median, 49 years), presenting with an actinomycotic abscess with a cryptoglandular anal fistula were included for study. The main symptom was an acute painful ischioanal abscess. One patient exhibited macroscopic small yellow granules ("sulfur granules"), another "watery pus" and a third subcutaneous gluteal septic metastasis. All patients were overweight (body mass index ≥ 25 kg/m2). Histological study of surgically excised tissue established the diagnosis. All the patients were managed with a combination of classical surgical treatment and prolonged antibiotic therapy. No recurrence was observed during follow-up, the median follow-up being 3 years.

Conclusion: Actinomycosis should be suspected particularly when sulfur granules are present in the pus, patients have undergone multiple surgeries or suppuration has an unusual aspect. Careful histological examination and appropriate cultures of pus are needed to achieve complete eradication of this rare, but easily curable, disease.

Keywords: Anal abscess; Cryptoglandular origin; Fistula-in-ano; Actinomycosis.

Fig. 1.

Actinomycosis in an anal fistula. The characteristics of an actinomycotic granule can be seen, enveloped by a purulent exudate (H&E, ×200).