title: Brush border enzymes and absorptive capacity in extrahepatic portal venous obstruction in children.
abstract: OBJECTIVE
  Portal hypertension may affect intestinal functions, brush border enzymes and absorption parameters. Information about these in extrahepatic portal venous obstruction (EHPVO) in children is limited and poorly reported. We therefore studied the brush border enzymes and absorptive capacity in EHPVO in children.
  
  
  METHODS
  The study was conducted on 52 children of EHPVO. The diagnosis of EHPVO was made on the basis of clinical presentation and ultrasound examination. All patients underwent upper gastrointestinal endoscopy. Endoscopic tissue biopsies from duodenum were taken on aluminum foils and kept immediately at -20°C for estimation of brush border enzymes. Tissue biopsies were homogenized in sodium maleate buffer, 0.1 M pH 6.0, by a homogenizer and processed for the enzymes: lactase, maltase, and sucrase. Enzyme levels were compared to normal healthy controls (n = 20). d-Xylose test, stool acid steatocrit for fat excretion in stools and stool alpha-1 antitrypsin were done to know about the absorptive parameters.
  
  
  RESULTS
  Enzyme levels of lactase (6.21 ± 5.67 IU/mg) and sucrase (37.07 ± 21.06 IU/mg) in EHPVO group were significantly lower as compared to lactase (23.32 ± 10.48 IU/mg) and sucrase (95.96 ± 46.55 IU/mg) in normal healthy controls. Maltase levels were lower, but difference was not statistically significant in EHPVO group (56.90 ± 28.65 IU/mg) as compared to normal controls (63.28 ± 22.88 IU/mg). There was no significant difference of urinary d-xylose and stool fat in patients with normal or short stature EHPVO patients.
  
  
  CONCLUSIONS
  EHPVO leads to decrease in levels of brush border enzymes in small bowel but their absorption capacity remains normal.
authors.affiliation: Division of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Gastroenterology, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, 160012 India.
authors.forename: Gurbakhshish Singh
authors.initials: GS
authors.lastname: Sidhu
authors.forename: B R
authors.initials: BR
authors.lastname: Thapa
authors.forename: Pawan
authors.initials: P
authors.lastname: Rawal
authors.forename: K K
authors.initials: KK
authors.lastname: Prasad
authors.forename: C K
authors.initials: CK
authors.lastname: Nain
authors.forename: B
authors.initials: B
authors.lastname: Nagi
authors.forename: Kartar
authors.initials: K
authors.lastname: Singh