Nerve Dysfunction in IBS

Introduction to Nerve Dysfunction

Approximately two-thirds of patients with IBS demonstrate visceral hypersensitivity, a state where nerves become abnormally sensitized and overreact to normal gut stimuli, according to the American Gastroenterological Association 1, 2

Inflammatory mediators directly act on nociceptor nerve terminals, upregulating their sensitivity and excitability, leading to primary hyperalgesia and allodynia in IBS patients, as reported by the European Society of Gastrointestinal Motility 1, 3
Between 6-17% of IBS patients develop symptoms following gastroenteritis, with increased mucosal T lymphocytes altering the environment around nerve terminals, according to the American College of Gastroenterology 1, 3
Activated mast cells cluster in close proximity to nerve endings in the gut mucosa, with the severity and frequency of abdominal pain correlating with this proximity, as found by the British Society of Gastroenterology 2, 4

Increased excitability of spinal neurons results in amplification of pain signals from both nociceptive and non-nociceptive inputs in IBS patients, as reported by the International Association for the Study of Pain 1, 3
IBS patients show greater radiation of pain to somatic structures during gut stimulation compared to healthy individuals, according to the European Federation of Neurological Societies 1, 3
Hyperexcitability of spinal nociceptive processes occurs in a subgroup of IBS patients, associated with failure of descending inhibitory control mechanisms, as found by the American Academy of Neurology 5, 6

Reduction in parasympathetic activity combined with increased sympathetic nervous system activity is a consistent finding in IBS, according to the American Autonomic Society 2, 4
Reduced vagal tone impacts gut motility, visceral sensitivity, peripheral inflammation, and gut permeability in IBS patients, as reported by the European Society of Neurogastroenterology and Motility 2, 4

Visceral hypersensitivity affects 20-60% of IBS patients, with enhanced perception to mechanical or electrical gut stimulation, as found by the American Gastroenterological Association 2, 4
Approximately 90% of high-amplitude propagating contractions coincide with abdominal pain or cramps in IBS patients, according to the American College of Gastroenterology 1
Some IBS patients develop fibromyalgia, demonstrating that nerve sensitization extends beyond the gut, as reported by the European League Against Rheumatism 1, 3