Postanal sinus: single or different etiologies?

Area of Science:

• Pediatric Surgery
• Developmental Biology
• Colorectal Surgery

Background:

• Postanal sinus (PAS) presents as a perianal fistula in the posterior midline, often observed in young females.
• Initial presentation suggests a uniform etiology due to similar patient demographics and lesion location.

Observation:

• Five female patients presented with a midline posterior perianal fistula, diagnosed as a postanal sinus.
• Examinations ruled out connections to pelvic organs, confirming the sinus nature of the condition.
• One patient exhibited a scimitar sacrum; surgical excision was performed via transanal or posterior sagittal approaches.

Findings:

• Histological examination revealed diverse pathologies, including epithelial types, dermoid, and epidermoid cysts, refuting a single etiology.
• All patients maintained normal anal function postoperatively.

Implications:

• Postanal sinus should be considered a potential indicator of various retrorectal developmental anomalies.
• Differentiating PAS from a simple fistula-in-ano is crucial for appropriate management and understanding of underlying causes.
• Early diagnosis and surgical intervention can lead to favorable outcomes regarding anal function.