T.D. Woodruff1, K.E. Cermack1, D.B. Blatt2, S. Bond3,4, C. Buonpane3,4, S.R. Carter3,4 1University Of Louisville, School Of Medicine, Louisville, KY, USA 2Norton Children’s Hospital, Pediatric Infectious Disease, Louisville, KY, USA 3University Of Louisville, Department Of Surgery, Louisville, KY, USA 4Norton Children’s Hospital, Pediatric Surgery, Louisville, KY, USA
Introduction: Pilonidal disease is a common acquired condition in hirsute, glandular, overweight teenagers that causes debilitating wounds involving the gluteal cleft. Embedded hairs block follicles resulting in recurring inflammatory changes that can lead to infection, pain, drainage and tunneling sinuses. While skin flora are most commonly implicated in abscesses, actinomyces historically has been identified as a rare pathogen in infected cysts. Despite the paucity of literature describing actinomyces in pilonidal disease, an increasing number of species have been identified in recent cultures performed at our institution. Some ambiguity remains regarding appropriate antimicrobial therapy for this potentially indolent and chronic infection with some literature suggesting prolonged (6-12 month) high doses of penicillin G or amoxicillin. The aim of this study is to determine whether identification of actinomyces in a pilonidal abscess should affect management strategy. We hypothesize that long duration of antibiotics will not impact outcomes for these patients.
Methods: A retrospective review of pediatric patients (</= 18 years) with pilonidal disease at a single tertiary care children’s hospital was performed from 2019-2024. Primary outcomes were recurrence of pilonidal cyst requiring surgical intervention and duration of antibiotics.
Results: 152 patients underwent 207 operations for pilonidal disease. The average age was 16 years (range 9-18). Seventy-one percent were female, 54% Caucasian, 39% black, 94% with English as a primary language. 180 (87%) had an abscess drained at the time of surgery. Cultures were predominantly monomicrobial (63%). Actinomyces was identified in 54 specimens (35.3%). Seventy five percent of all patients were prescribed antibiotics post operatively, with wide variation in type and duration (3 days – 6 months). The longest duration was seen in four patients with actinomyces isolates, who were referred to pediatric infectious disease. Of the 50 patients not referred, 45 were prescribed 5-10 days of oral antibiotics including amoxicillin, amoxicillin/clavulanate, trimethoprim/sulfamethoxazole, cephalexin, and clindamycin. Five patients were treated with surgery alone.
The presence of actinomyces in cultures did not affect recurrence rates (p=0.25). No recurrences were observed in patients with actinomyces who did not receive antibiotics. There was no difference whether actinomyces was present in mono- or polymicrobial infection (p=0.74). Duration of antibiotic therapy did not affect recurrence rates for patients with actinomyces when comparing long (3-6 months) versus short duration (0-10days) (p=0.83).
Conclusion: Actinomyces identification in isolates for pilonidal abscess appears more common than previously described in the literature. Identification of actinomyces in pilonidal abscesses did not affect patient outcomes or require long duration of antibiotics in the vast majority of cases treated.