A 46-year-old man had a screwdriver pulled out of his rectum after pushing it inside himself and leaving it there for a week.

In a disturbing case report, doctors revealed the man suffered a perforated bowel as a result and was left critically ill.

He had arrived at a hospital in Florida with life-threatening septic shock because of bacteria which got into his bloodstream through the injury.

But only when a CT scan was performed did doctors find the tool responsible, which measured 8.2inches long by 1.1inches wide (21cmx3cm).

After surgery, the unidentified man needed surgery to cut away rotting flesh from inside his buttock after it became infected.

He survived, and is believed to be the first reported case of this kind. It is not clear which end of the screwdriver was inserted first.

It is also unclear why he inserted the screwdriver in the first place, but he has since needed treatment for psychiatric disorders.

The story was detailed in the Annals of Medicine and Surgery by authors led by Dr Youssef Shaban, from the Kendall Regional Medical Center in Miami.

They revealed the man had sought emergency help after having abdominal and pelvic pain for a week.

His past medical history showed he had suffered with schizophrenia and bipolar disorder and he failed to take medication properly.

A CT scan revealed a foreign object in the rectum which doctors quickly recognised as a screwdriver.

There were clear signs his bowel was damaged so doctors immediately gave him antibiotics and rushed him into the operating theatre.

Initial attempts to remove the screwdriver were unsuccessful because it was too big and there was hardened faeces in the way.

Therefore, doctors had to slice into the abdominal cavity in order to investigate.

They found the metal end of the screwdriver had made a hole in the large intestine, and then pierced the buttock muscle, damaging tissue between the penis and anus.

Surgeons sewed the hole back up and drained fluid from a large abscess in his right buttock.

But the man did not become stable for two days and he had to be kept on an IV drip in intensive care to fight off his septic shock.

In order to save his life, doctors performed an ileostomy, in which his bodily waste was rerouted from his intestines to a bag outside his body.

The wound on his buttock started to rot so surgeons had to operate again to get rid of the dying flesh.

‘At two weeks follow up the patient was doing well with a functioning ostomy and ostomy reversal was planned,’ the doctors said.

‘The patient recovered and was discharged to Behavioral Health for inpatient treatment of his psychiatric disorders.’

The case is unique but serves as a warning to doctors to be suspicious of stomach pain in psychiatric patients, the doctors said.

They added: ‘There have been two previously documented cases in the literature in which screwdrivers were discovered in the colon, both however, without bowel perforation.’

The first case reported was in 1861, when a prisoner inserted a tool box measuring 12.7cm by 15.2cm (5inches by 6inches) that led to his death a week later.

A second patient, a 56-year-old man with a psychiatric condition, had a screwdriver removed from his rectum with huge forceps while he was bent over.

Dr Shaban wrote: ‘The most common reason, by far, for anal foreign body insertion is sexual pleasure.

‘However other documented explanations include drug concealment, assault, “accidental”, psychiatric reasons, and to alleviate diarrhoea or constipation.

‘The patient may not be forthcoming initially with the critical information as it may be an embarrassing situation.’

Surgery is a difficult task because there is a lack of research suggesting the best course of action.

Dr Shaban wrote: ‘As the size of the perforation and gross contamination or spillage of faecal material increases there is less unanimity among surgeons as to the exact surgical approach.’