A woman who thought she was suffering from debilitating Crohn's disease and underwent surgery to treat the condition has discovered that a Heinz sauce sachet lodged in her bowel was the culprit.

The 41-year-old was diagnosed with the bowel condition after complaining about severe stomach pain and bloating six years ago.

When she failed to respond to treatment and started to develop "severe" symptoms of the disease, doctors at the Heatherwood and Wexham Park Hospital in Slough decided that her only remaining option was keyhole surgery.

During surgery, the real source of her painful symptoms was revealed. Surgeons found an inflamed mass lodged in the wall of her intestine, which consisted of two pieces of plastic bearing the Heinz logo.

Once she had the sachet removed from her bowel, the patient's symptoms cleared up almost immediately and all supposed symptoms of Crohn's disease vanished.

Doctors have said it is the first time ingested plastic packaging has mimicked the symptoms of Crohn's disease, according to the British Medical Journal (BMJ). Previously, swallowed toothpicks had a similar result. Only 1% of cases involving swallowed foreign items require surgery.

"It is important to consider alternative surgical diagnoses in patients with presumed Crohn's disease unresponsive to standard treatment," the BMJ report said.

The woman said she had no memory of ever swallowing the Heinz sauce sachet, according to Sky News.