ABSTRACT
An immunoprecipitation method for the determination of human intestinal alkaline phosphatase (I-AP) in feces is described using anti-human I-AP IgG. Antibodies to human I-AP are monospecific after absorption with human placental alkaline phosphatase and show no cross-reactions with human liver alkaline phosphatase or alkaline phosphatase from E. coli. Normal controls demonstrate a logarithmic normal distribution of I-AP activity in feces. The standard deviation of the intra- as well as of the inter-assay variation is 11.7%. This method represents a simple quantitative non-invasive in vivo assay for brush border damage under experimental and/or clinical conditions.
Subject(s)
Alkaline Phosphatase/immunology , Feces/enzymology , Immunologic Techniques , Intestines/enzymology , Animals , Antibody Specificity , Antigen-Antibody Reactions , Cross Reactions , Escherichia coli/enzymology , Fluorescent Antibody Technique , Humans , Liver/enzymology , RatsABSTRACT
The intestinal alkaline phosphatase (I-AP) in feces was investigated in 16 patients with adult coeliac disease and 2 patients with gluten-sensitive enteropathy in dermatitis herpetiformis using an immunoprecipitation method. The mean concentration of I-AP activity in feces was reduced by 76% in patients with coeliac disease in comparison to normal controls (11.5 : 47.5 U/g). Patients with total villous atrophy (mean = 5.3 U/g) demonstrated a lower activity than patients with partial villous atrophy (mean = 14.3 U/g). Follow-up studies showed stable fecal I-AP-activities in symptom-free patients, whereas patients with relapses were characterized by fluctuating activities. The administration of a single oral dose of 31 g gluten is followed by a fecal I-AP-excretion pattern similar to toxic damage of the small bowel mucosa.
Subject(s)
Alkaline Phosphatase/metabolism , Celiac Disease/enzymology , Feces/enzymology , Intestine, Small/enzymology , Glutens/metabolism , Humans , Liver/enzymology , Protein-Losing Enteropathies/enzymologyABSTRACT
In comparison to normal controls (n = 71) the activity of intestinal alkaline phosphatase in feces is reduced in chronic bowel disease using an immunoprecipitation method: patients with Crohns disease (n = 40) or inactive ulcerative colitis (n = 29) demonstrate small changes of fecal intestinal alkaline phosphate activity in comparison to normal controls. Intestinal alkaline phosphatase is reduced in patients with active ulcerative colitis (n = 11) to 50%, in patients with uraemic enteropathy (n = 18) to 30% and in patients with coeliac disease (n = 14) to 20% of the activity observed in normal controls. During cytostatic treatment of malignant tumors, fecal intestinal alkaline phosphatase activity increases as a sign of toxic damage of the intestinal mucosa.
