Secretin-cerulein test and fecal chymotrypsin concentration in children with intestinal giardiasis.

We studied six patients with giardiasis (five males, one female), median age 3.5 yr (range 1-11) and 12 healthy control subjects (10 males, 2 females), median age 3.5 yr (range 1-10). Intestinal biopsy and a contemporaneous secretin-cerulein test were performed in all patients, and fecal chymotrypsin was also assayed. Intestinal biopsy was normal in five of the six patients with giardiasis, whereas one of the six presented a partial atrophy of the intestinal villi. The secretin-cerulein test (1 CU/kg of secretin + 75 ng/kg of cerulein) did not show any significant difference between values in the outputs of chymotrypsin, lipase, phospholipase, and bicarbonate obtained in patients and in controls; however, in the one patient with partial intestinal mucosal atrophy, all enzymatic activity levels were below the normal limit for our laboratory. Furthermore, the mean values of fecal chymotrypsin concentration did not differ between the two groups. Fecal chymotrypsin was also reduced in the patient with an abnormal secretin-cerulein test; a second assay performed 3 mo after the suspension of treatment (Metronidazole), however, showed a normal chymotrypsin concentration.