Is irritable bowel syndrome an organic disorder?

Table 2 Abnormalities in the densities of gastrointestinal endocrine/paracrine cells in patients with sporadic irritable bowel syndrome

Gastrointestinal segment	Endocrine cell type	IBS-D	IBS-M	IBS-C
Stomach
Oxyntic mucosa	Ghrelin	High	Normal	Low
	Serotonin	High	Normal	Low
	Somatostatin	Low	Low	High
	Chromogranin A	Normal	Normal	High
Antrum	Serotonin	Normal	Low	High
	Gastrin	High	High	High
	Somatostatin	Low	Low	Low
	Chromogranin A	Normal	Low	High
Small intestine
Duodenum	Serotonin	Normal	-	Normal
	CCK	Low	-	Normal
	Secretin	Low	-	Normal
	GIP	Low	-	Low
	Somatostatin	Low	-	Low
	Chromogranin A	Low	-	Low
Ileum	Serotonin	Low	Low	Low
	PYY	Normal	Normal	High
	Chromogranin A	Low	Low	Low
Large intestine
Colon	Serotonin	Low	-	Low
	PYY	Low	-	Low
	Chromogranin A	Low	-	Low
Rectum	Serotonin	Normal	-	Normal
	PYY	Low	-	Low
	Enteroglucagon	Low	-	Low
	Somatostatin	High	-	High
	Chromogranin A	Normal	-	Normal

CCK: Cholecystokinin; PYY: Peptide YY; GIP: Gastric inhibitory peptide; IBS-C: Irritable bowel syndrome (IBS) with constipation as the predominant bowel symptom; IBS-D: IBS with diarrhea as the predominant bowel symptom; IBS-M: IBS with both constipation and diarrhea as the predominant bowel symptoms.