PROTON-PUMP INHIBITION AND GASTRIC GIARDIASIS - A CAUSAL OR CASUAL ASSOCIATION

Two patients who developed gastric giardiasis after 2 weeks of treatme nt with omeprazole 20mg b.i.d. followed by omeprazole 20mg per day for 2-6 weeks are described. In one patient, gastric giardiasis occurred in the presence of only mild intestinal metaplasia. In the other patie nt, Giardia lamblia infection had resolved 4 weeks after the cessation of omeprazole treatment, which, to our knowledge, is the first case r eported in the literature. It is tempting to speculate that gastric gi ardiasis can develop in the absence of mucosal abnormalities during hy pochlorhydria induced by treatment with a high dose of a proton-pump i nhibitor. Specific treatment may not be required if the drug can be st opped and no other gastric disease causing hypochlorhydria is present.