A correlative study of duodenal aspirate and faeces examination in giardiasis, before and after treatment with metronidazole

In a study of 95 patients with giardiasis it was shown that examination of duodenal aspirates for Giardia Lamblia can supplement but not replace examination of faeces in the detection and follow-up of cases. The chances of finding trophozoites in duodenal aspirate is greater in those with trophozoites in the faeces than in cyst passers. Patients were treated with metronidazole in either conventional dosage (400 mg.t.d.s. for 7 days) or with a single 'hammer dose' of 2400 mg. Results showed that the parasites may persist in the duodenum and faeces after conventional therapy, though the incidence was not very high; and it is suggested that a single large dose of metronidazole may be equally if not more effective than divided doses spread over a few days.