Somatosensory changes in the referred pain area in patients with cholecystolithiasis.
OBJECTIVE
Patients with abdominal pain provoked by acute cholecystitis increase the somatic sensitivity in the referred somatic pain area. Our aim in the present paper was to examine somatosensory changes in the referred pain area (previously evoked by painful attacks) in patients with uncomplicated gallstone disease and to evaluate the possible relation between referred pain patterns and clinical findings. Somatosensory changes in these areas may be important in the persistent pain after treatment and may help to develop treatment strategies for abdominal pain in the post-cholecystectomy syndrome.


METHODS
Forty-two patients with symptomatic cholecystolithiasis, confirmed ultrasonographically, were studied in the pain-free period.


METHODS
Sensitivity and pain thresholds for standardized experimental sensory testing including different modalities: pinprick, pinching, heat, cold, pressure, and single and repeated electrical stimulation were studied in the area where the pain was referred to during the acute attacks, and in a control area on the contralateral side of the abdomen.


RESULTS
Patients with verified cholecystolithiasis showed hyperalgesia to pinprick (26% of subjects, P < 0.05) and cold stimuli (21% of subjects, P < 0.05) in the referred pain area. There was also a significant reduction in sensation/pain thresholds (indicating hyperalgesia) in the referred pain area to single (P = 0.007/P = 0.002) and repeated electrical (P = 0.017/P = 0.043) stimuli, as well as in pain threshold to pinching and mechanical stimuli (P = 0.049/P < 0.001). There were no significant relations between the hyperalgesia and the clinical findings.


CONCLUSIONS
Cholecystolithiasis leads to significant hyperalgesia in the somatic area, where pain was referred to during the acute attacks. This is explained by viscero-somatic convergence mechanisms in the central nervous system. Therefore, central neuroplastic changes may be significant in diseases related to the gallbladder such as the post-cholecystectomy syndrome.
Stawowy
Marek
M
Department of Surgical Gastroenterology, Aarhus University Hospital, Denmark. msta@stofanet.dk
Funch-Jensen
Peter
P
Arendt-Nielsen
Lars
L
Drewes
Asbjørn Mohr
AM
D000208:Acute Disease; D000328:Adult; D000368:Aged; D041761:Cholecystolithiasis / Q000503:physiopathology*; D003080:Cold Temperature; D004558:Electric Stimulation / Q000379:methods; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006358:Hot Temperature; D006801:Humans; D006930:Hyperalgesia / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000503:physiopathology*; D017288:Pain Threshold; D010812:Physical Stimulation / Q000379:methods; D011312:Pressure