Fecal intestinal alkaline phosphatase in coeliac disease.

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.