Supralevator Abscess

A supralevator abscess is a deep anorectal collection located above the levator ani.

It can arise by upward extension of an intersphincteric abscess or by cephalad extension from an ischioanal abscess. The route of origin determines the safest route of drainage.

Incorrect drainage can create a complex extrasphincteric fistula.

Patients may have severe deep pelvic or rectal pain without a visible perianal swelling.

Features include fever, pelvic pressure, tenesmus, urinary retention and pain during rectal examination.

The diagnosis is often delayed because external inspection can appear normal.

Pelvic MRI or contrast CT: define the supralevator collection and, importantly, determine whether it originated from the intersphincteric or ischioanal space.

Drain urgently.

If the supralevator abscess arose by upward extension of an intersphincteric abscess, drain internally through the rectum or anal canal.

If it arose by upward extension from an ischioanal abscess, drain externally through the ischioanal space.

This preserves the original anatomical route and reduces creation of an iatrogenic complex fistula.

A supralevator collection caused by pelvic intra abdominal disease may instead require transabdominal, transrectal or image guided drainage according to its source.

Treat systemic sepsis simultaneously with appropriate broad antimicrobial therapy.

Persistent sepsis after drainage warrants repeat imaging for residual loculations or another pelvic source.