When I doctored this TSA logo last week, who knew I was being literal!

I wish to bring to your attention difficulties one of my patients recently encountered when entering the USA. He is a 48-year-old man with a fistula-in-ano managed with a long-term seton to control perianal sepsis.

A seton consists of a length of suture material knotted to form a loop which lies in the fistula track. It passes through the fistula, out of the external opening beside the anus, into the anus, and re-enters the fistula through the internal opening. Various different materials can be used; in this case the seton was made of a turquoise braided synthetic suture. Many fistulas are treated with setons in the short term, and, in those that are high or associated with Crohn's disease, this management can be long-term.

On arrival in New York in August, 2006, for a holiday, the patient was interrogated by immigration officials, then examined and searched. The presence of the seton gave rise to much concern, I assume because of a suspicion that a drug package or terrorist weapon was in some way attached to it. A rectal examination was done, during which the examining official pulled very hard on the seton, causing severe pain, but fortunately not damaging the anal sphincter muscles encircled by it.

The patient was refused entry into the country unless the seton was removed. Given the somewhat stark choice, he chose removal of the seton, which was done by a doctor at the airport who claimed never to have come across one before. The patient now requires an examination under general anaesthetic to insert a replacement.

Great.