title: Low trehalase activity is associated with abdominal symptoms caused by edible mushrooms.
abstract: BACKGROUND
  The purpose of the study was to evaluate whether maldigestion of trehalose causes abdominal symptoms and which available diagnostic method best distinguishes intolerant from tolerant subjects.
  
  
  METHODS
  A 25-g oral trehalose load test was performed in 64 subjects. The 19 experiencing clear symptoms constituted the trehalose-intolerant subjects. Changes from base-line levels of blood glucose, breath hydrogen, and methane and symptoms were recorded after the test. Trehalase activity was determined in serum and on a duodenal biopsy specimen obtained by endoscopy.
  
  
  RESULTS
  Intolerant subjects were best differentiated from tolerant subjects by changes in breath gases (hydrogen and methane) and duodenal trehalase to sucrase ratio. The change in breath gases correlated inversely with duodenal trehalase activity, duodenal trehalase to sucrase ratio, and plasma trehalase activity. The correlation between serum and duodenal trehalase activities was on the order of 0.6. Two subjects were found to have trehalase deficiency.
  
  
  CONCLUSIONS
  It is obvious that trehalose maldigestion can cause symptoms similar to those of lactose maldigestion and intolerance. Three factors control the genesis of symptoms: 1) the activity of small-bowel trehalase: if it is low, trehalose is maldigested and more trehalose is passed into the colon; 2) the maldigested trehalose, which causes osmotic water flow into the colon, resulting in loose stools and diarrhea; and 3) most importantly, the microflora of the colon, from which symptoms will arise if there are bacteria capable of producing gases from maldigested trehalose. If colonic bacteria cannot produce gases, then distention of the abdomen and intestinal gas expulsion as eructations and flatus will not occur.
authors.affiliation: Tampere Occupational Health Center, Dept of Clinical Chemistry, University Hospital of Tampere, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Arola
authors.forename: T
authors.initials: T
authors.lastname: Koivula
authors.forename: A L
authors.initials: AL
authors.lastname: Karvonen
authors.forename: H
authors.initials: H
authors.lastname: Jokela
authors.forename: T
authors.initials: T
authors.lastname: Ahola
authors.forename: M
authors.initials: M
authors.lastname: Isokoski
mesh_terms: D015746:Abdominal Pain / Q000209:etiology; D000328:Adult; D000363:Agaricales / Q000378:metabolism*; D001706:Biopsy; D001944:Breath Tests; D004186:Disaccharidases / Q000097:blood / Q000172:deficiency / Q000378:metabolism; D004386:Duodenum / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D008286:Malabsorption Syndromes / Q000201:enzymology / Q000209:etiology* / Q000378:metabolism; D010945:Plants, Edible / Q000009:adverse effects / Q000378:metabolism; D014198:Trehalase / Q000097:blood / Q000172:deficiency / Q000378:metabolism*; D014199:Trehalose / Q000097:blood / Q000378:metabolism*
chemical_list: D014199:Trehalose; D004186:Disaccharidases; D014198:Trehalase