Somatic pain sensitivity in children with recurrent abdominal pain

OBJECTIVE: Evidence is accumulating that recurrent abdominal pain (RAP) in children is associated with visceral hyperalgesia. However, it is not known whether somatic sensitivity is altered as well. Therefore, the aim of our study was to assess somatic pain sensitivity in children with RAP and healthy controls at the abdomen and a distal site (thenar).
METHODS: We examined 20 children with RAP (age 8–14) and 23 healthy control children (age 9–14). Heat and mechanical pain thresholds as well as measures of perceptual sensitization in response to repetitive mechanical or tonic thermal noxious stimulation were assessed.
RESULTS: At the abdominal site, pain sensitivity in children with RAP did not differ significantly when compared to controls. At the thenar, pain thresholds of children in the RAP group were not significantly different from control children. However, children with RAP showed less perceptual sensitization in response to tonic heat and repetitive mechanical stimuli (ps ≤ 0.05) than controls.
CONCLUSIONS: We found no evidence for somatic hyperalgesia in RAP arguing against generalized hyperalgesia in these children. Somatic hypoalgesia at the thenar might either be related to a dysregulation of sensory processing and/or attentional avoidance of pain-related stimuli.