Infantile perianal pyramidal protrusion

A 2-year-old girl presented to the dermatology clinic with a 2-week history of a solitary perianal protrusion. Her parents said she had shown no signs of pain or pruritus. She had no history of bleeding or excoriation at the site. Her medical history was unremarkable except for intermittent constipation over the previous 6 months. On physical examination, we saw a pink, soft prominence shaped like a hen’s crest in the perineal median raphe, anterior to the anus (Figure 1). We diagnosed infantile perianal pyramidal protrusion based on clinical presentation. Her constipation resolved with dietary fibre supplementation and polyethylene glycol. The skin protrusion substantially decreased in size after 3 months without any other intervention.

• Download figure
• Open in new tab
• Download powerpoint

Figure 1:

A pink, hen’s crest–shaped, soft prominence located in the perineal median raphe anterior to the anus of a 2-year-old girl.

Infantile perianal pyramidal protrusion is a benign perianal skin condition that occurs most commonly in girls younger than 5 years, but occasionally in boys and adults.1^–3 Anatomic weakness of the perineum or median raphe may contribute to its development.2^,4 Differences in perineal anatomy between the sexes may explain why infantile perianal pyramidal protrusion is more common in girls. Constipation may be a risk factor for the condition.2^,4 Infantile perianal pyramidal protrusion typically presents as an asymptomatic, smooth, soft, pink-or flesh-coloured skin prominence ranging from 5 to 30 mm² in size, usually located anterior, but occasionally posterior to the anus.1^,2 Diagnosis is primarily clinical, and invasive investigations should usually be avoided. Differential diagnosis should consider skin tag, skin fold, condyloma acuminata, hemorrhoid, rectal prolapse and lesions from perianal abuse.1^,2 Conservative management is indicated as the lesion often resolves spontaneously within weeks to months. Treatment of constipation, if present, is beneficial.1^,2