Nippostronglylus brasiliensis infection in the rat: effect of iron and protein deficiency and dexamethasone on the efficacy of benzimidazole anthelmintics.

Abstract

SUMMARY Malnutrition, anaemia, and gut parasites are commonly interrelated. Using the Nip-postrongylus brasiliensis-rat model, the effect of iron and protein deficiency on the efficacy of benzimidazole anthelmintics was studied. It was demonstrated that the anthelmintics mebendazole and fenbendazole were significantly less effective in eradicating parasites when animals were deficient in iron and protein. This decreased efficacy of anthelmintics in iron and protein deficiency could not be overcome by intraperitoneal administration of the drug. Since nutritional deficiencies may act via impairment of the immune response, anthelmintic efficacy was determined in adequately nourished rats treated with the immunosuppressive drug dexamethasone. A similar decrease in efficacy of mebendazole was shown when these animals were treated with dexamethasone. Thus it is possible that lowered anthelmintic efficacy in iron and protein deficient animals is mediated by immune deficiency. These findings may be relevant to anthelmintic programmes in malnourished communities.

THE EFFECT OF IRON AND PROTEIN DEFICIENCY ON PLASMA LEVELS AND PARASITE UPTAKE OF [14C] FENBENDAZOLE IN RATS INFECTED WITH NIPPOSTRONGYLUS BRASILIENSIS

“…The most important finding is that the worms in the deficient rats took up significantly less ^•'C from the [^""C] fenbendazole. This observation mav in part explain the reduced efficacy of benzimidazoles and perhaps other anthelmintics in such nutritionally deprived rats (Duncombe et al, 1977;1979). Reduced uptake of anthelmintic by the worms may be due to a number of factors.…”

“…Reduced uptake of anthelmintic by the worms may be due to a number of factors. Bolin et al (1977) obtained evidence that protein and/or iron-deficient rats had impaired immunological responses to A', brasiliensis. It is known that worms under immunological attack respond in various ways.…”

“…The process is cyclic as malnutrition may potentiate further infection by reducing the capacity of the host to mount a protective immune response. Bolin et al (1977) described a significant delay in the expulsion of Nippostrongylus brasiliensis from the intestine of iron and/or protein-deficient rats. In these diet-deficient rats the efficacy of the anthelmintics mebendazole, pyrantel and piperazine against N. brasiliensis was impaired (Duncombe et al, 1977;1979).…”

“…Bolin et al (1977) described a significant delay in the expulsion of Nippostrongylus brasiliensis from the intestine of iron and/or protein-deficient rats. In these diet-deficient rats the efficacy of the anthelmintics mebendazole, pyrantel and piperazine against N. brasiliensis was impaired (Duncombe et al, 1977;1979). Treatment of adequately nourished rats with the immunosuppressant dexamethasone prior to mebendazole administration similarly reduced anthelmintic efficacy.…”

Hookworm Disease: Nutritional Implications

“…Inadequate intake of protein and iron has been found to reduce the antihelminthic effect of benzimidazoles in rats infected with N. braziliensis [61].…”