In women presenting to gynaecological clinics with lower abdominal pain, the cause is frequently attributed to endometriosis irrespective of whether it is found to be minimal or extensive at laparoscopy.
Irritable bowel syndrome (IBS) is also common in this setting, and it was speculated that the visceral hypersensitivity associated with this condition might be amplifying the symptoms of endometriosis.
Professor Whorwell and colleagues from the United Kingdom assessed visceral sensitivity to balloon distension, symptoms and psychological status following laparoscopy.
|Controls undergoing laparoscopy had normal sensitivity|
The team evaluated 20 women with minimal to mild endometriosis, 20 with moderate to severe endometriosis, 20 with laparoscopy negative abdominal pain, and 20 asymptomatic women undergoing laparoscopic sterilisation who acted as controls, and compared with 20 women with IBS.
Compared with controls, patients with minimal to mild and moderate to severe endometriosis had a higher prevalence of symptoms consistent with IBS with significantly lower mean pain thresholds, not explained by differences in rectal compliance.
The team observed that patients with laparoscopy negative pain had symptoms and visceral sensitivity similar to patients with IBS.
The research team noted that controls undergoing laparoscopy had normal sensitivity, indicating that the laparoscopic procedure was not inducing hypersensitivity.
Professor Whorwell commented, "Visceral hypersensitivity is extremely common in endometriosis and could be intensifying the pain."
"This finding might explain why mildly affected individuals often complain of severe symptoms out of proportion to the extent of their disease."
"This study has introduced a completely new concept into the understanding of pain in endometriosis and could open up new opportunities for treatment."