Anorectal stenosis after treatment with tumor necrosis factor alpha antibodies: a case series

We identified three patients who developed anorectal stenosis after successful treatment with anti-tumor necrosis factor alpha (anti-TNF-alpha) agents.

Two patients, a 24-year-old Irish Caucasian man and a 64-year-old Irish Caucasian woman, developed symptoms attributable to anorectal stenosis four to six weeks after treatment. A further patient, a 25-year-old Irish Caucasian male, presented three years after treatment with anorectal stenosis, having been asymptomatic with his stenosis for the preceding three years. No patients had evidence of active inflammation at time of representation or had previous anal canal surgery.

Anorectal stenosis in these patients appears to be independent of active inflammation. No other cause of new stenosis could be identified. We postulate that rapid clinical response to anti-TNF-alpha agents led to aberrant mucosal healing. This in turn led to anorectal stenosis. This is the first report of this complication in association with the use of biologic agents.