Sensitivity disturbances in patients with irritable bowel syndrome and fibromyalgia.
BACKGROUND
Although visceral hypersensitivity is a common feature among patients with irritable bowel syndrome (IBS), studies on somatic sensitivity have given controversial results.


OBJECTIVE
To assess visceral sensitivity in response to isotonic rectal distensions and somatic sensitivity at different layers of the body wall (skin, subcutis, and muscle) in patients with IBS and fibromyalgia (FM), within and outside the area of abdominal pain referral.


METHODS
We studied 10 patients with IBS, 5 patients with FM, 9 patients with IBS+FM, and 9 healthy controls. Rectal distensions were performed by increasing tension at 4 g steps up to 64 g or discomfort. Pain thresholds to electrical stimulation were measured within and outside the areas of abdominal pain referral.


RESULTS
Patients with IBS and IBS+FM demonstrated rectal hypersensitivity in comparison to controls. The threshold of discomfort was 44 +/- 5 g in IBS and 36 +/- 5 in IBS+FM patients, while patients with FM and healthy controls tolerated all distensions without discomfort. In the areas of pain referral, pain thresholds of all three tissues of the body wall were lower than normal in all patients groups (p < 0.001). In control areas, the pain thresholds were normal in skin, and lower than normal in subcutis and muscle in IBS (p < 0.001). FM and IBS+FM demonstrated somatic hypersensitivity at all sites (p < 0.001 vs healthy).


CONCLUSIONS
Our observations seem to indicate that, although sharing a common hypersensitivity background, multiple mechanisms may modulate perceptual somatic and visceral responses in patients with IBS and FM.
Caldarella
Maria P
MP
Department of Medicine and Aging Sciences, Section of Internal Medicine and Gastroenterology, Centre for the Study of Aging, Gabriele D'Annunzio University and Foundation, Chieti, Italy.
Giamberardino
Maria A
MA
Sacco
Flora
F
Affaitati
Giannapia
G
Milano
Angelo
A
Lerza
Rosanna
R
Balatsinou
Crysanthi
C
Laterza
Francesco
F
Pierdomenico
Sante D
SD
Cuccurullo
Franco
F
Neri
Matteo
M
D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005356:Fibromyalgia / Q000150:complications / Q000503:physiopathology* / Q000523:psychology; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications / Q000503:physiopathology* / Q000523:psychology; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology; D017288:Pain Threshold / Q000502:physiology*; D010812:Physical Stimulation; D012007:Rectum / Q000503:physiopathology; D012867:Skin / Q000503:physiopathology