ABSTRACT
Giardiasis occurs most frequently in subtropical and tropical settings and in areas with poor sanitary conditions. Prevalence varies from 2 to 7% in developed countries to 40% in developing countries. In Egypt; the rate reported is around 15% in patients with gastrointestinal complaints. The histopathology of the upper and lower gastrointestinal tract of patients with giardiasis as shown by endoscopy and biopsy is ill defined. Reported histopathological changes in duodenum and gastric mucosa varies from 3.4% to 50% in different studies.Thirty two stool positive cases of giardiasis and 11 stool-Giardia negative controls were studied; biopsies were taken from duodenum and stomach [body and antrum] from each patient. In addition to studying the pathological changes, duodenal biopsies were studied for the presence of Giardia lamblia and gastric biopsies for Helicobacter pylori.Giardia lamblia were detected in 13 of 32 duodenal biopsies [40.6%], chronic inflammation in 27 cases [84%], partial villous atrophy in 13 [40.6%] and fibrosis in 5 cases [15.6%].Gastric histopathologic changes found were chronic antral gastritis in 29 cases [90.6%], Helicobacter pylori in 21 cases [65.6%], follicular gastritis in 11 cases [34.38%] and mild atrophy in 5 cases [15.5%]. Intraepithelial lymphocytes infiltration to lamina propria was 24 +/- 10.4 / 100 enterocytes. Comparison of gastric and duodenal histopathological changes in patients and controls showed significant difference in chronic antral gastritis [P = 0.007], intraepithelial lymphocytes infiltration [P = 0.04] and partial villous atrophy [P = 0.05]. Among the 32 patients group pathological changes were compared in Giardia positive with Giardia negative biopsies [for chronic inflammation 92.3% versus 78.9%, P = 0.322; for partial villous atrophy 46.2% versus 36.8%, P = 0.612 and for fibrosis 23.1% versus 10.5%, P = 0.159, for the 2 subgroups of Giardia positive and Giardia negative biopsies, respectively. Similar but less marked changes were seen in biopsies from the body of stomach, and changes in the antrum were unrelated to the presence of Giardia lamblia in the duodenum. A careful search for Giardia lamblia in stool is important in patients with the gastrointestinal complaints of abdominal cramps, bloating and or diarrhea. In such cases gastric and duodenal mucosal changes can be present even if Giardia is not found in biopsy specimens so long as stool is positive for Giardia lamblia