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115 patients with non-immune (IgE-negative) urticaria, related to parasitic (lambliasis, oxyuriasis, ascaridiasis) or fungal (candidiasis) associations were investigated-both before and one month after specific and antihistaminic therapy-concerning different percentage levels of blood lymphocyte sets and subsets, by means of flow cytometry. Before therapy, three kinds of immune deficiency patients were obtained, one in lambliasis and oxyuriasis, the second in ascaridiasis, and the third in candidiasis, respectively. Clinical, biological and immunological recovering after therapy exhibited some differences related to the presumed non-allergic etiology, i.e. better in lambliasis and oxyuriasis and worse in ascaridiasis and candidiasis.

A single dose of 2% albendazole suspension (400 mg in 20 ml) was administered to 77 patients (42 males and 35 females), ages ranging between 2 to 12 years, with helminthic infections. Ascariasis was the most prevalent infection. Patients were followed-up for 3 weeks. The results showed that albendazole was highly effective against Ascaris lumbricoides, Ancylostoma duodenale and Enterobius vermicularis. Significant improvement was also observed in patients having infections due to Trichuris trichiura. Albendazole was well tolerated and did not produce any significant side-effects. Single dose albendazole appears to be appropriate for mass chemotherapy to control intestinal nematode infections in highly infected communities.

Twenty ponies were allotted to 4 groups of 5 ponies each, and oxibendazole was orally administered at dose levels of 5, 10, 15, and 20 mg/kg. In the 3 groups of ponies given the largest doses, efficacy against 3 species of Strongylus was between 92 and 100% and that against small strongylids of the genera Cyathostomum, Cylicocyclus, Cylicodontophorus, and Cylicostephanus was more than 99%. All adults and 95 to 100% of larvae of the pinworm Oxyuris equi were removed. In the group of ponies given 5 mg/kg, 86 to 100% of the large strongylids and 84 to 100% of the small strongylids were removed, as were all larval and adult pinworms. Trichostrongylus axei was found only in 4 of the 5 ponies given 5 mg/kg; results were encouraging, but not consistent. Almost all of the Parascaris equorum were found in this group of ponies; no anthelmintic activity was detected at this dose level. Oxibendazole removed approximately 99% of small strongylid 4th-stage larvae. No efficacy against the larval stages of Gasterophilus intestinalis and against Habronema spp and Setaria equina was observed.

The high prevalence of intestinal parasitic infections as an index of underdevelopment, especially in tropical countries, is related to poverty, poor housing, lack of sanitation, malnutrition, and ignorance. The effects are lowered work capacity, physical and mental retardation, leading to recurrences and exacerbations of the parasitism and malnutrition. The most prevalent parasites, methods of detection by specific tests in patients in clinical trials involving antiparasitic drugs are dealt with. How and by whom investigations of new drugs should be undertaken, the need for a basic knowledge of parasitology and techniques of the discipline, of biostatistics, and use of such controls as randomized allotment to treatment groups, placebo administration, and double-blind assessments are emphasized. The justification for undertaking an evaluation of an antiparasitic drug is predicated on the demonstration of safety in exhaustive in vitro and animal studies and of the drug's potential superiority as to efficacy and lower incidence of unwanted side effects, as compared with existing agents. Tolerance and dose-range studies should be conducted in male adult hospitalized patients under close supervision. The evaluation of amebicides in clinical trials, as well as of anthelmintics, is considered in terms of differentiation and reproductive habits of specific causative agents and tests for detecting their elimination to determine improvement under drug therapy. The problem of reinfection, particuarly of nonhospitalized patients under the adverse conditions of life, is stressed.

This article discusses strongyloidiasis, hookworm infection, trichostrongyliasis, ascariasis, trichuriasis (whipworm infection), and enterobiasis (pinworm infection). For each infection, the author describes the organism, the epidemiology and geographic distribution, symptomatology and pathogenesis, and diagnosis and treatment.

Since ivermectin, a mixture of 2 closely related macrocyclic lactones, has proven highly effective against animal intestinal nematodes, trials were undertaken to determine its efficacy against human intestinal nematodes. We tested 110 patients with strongyloidiasis and 90 with enterobiasis; many had other intercurrent intestinal nematode infections. Stool examinations were done before and after patients were given a single dose of oral ivermectin capsules (50, 100, 150, or 200 micrograms/kg body wt); 55 recipients of 100 or 200 micrograms/kg doses received a second identical dose the next day. Kato and saline smears, ethyl acetate concentration, modified Baermann's technique, and Harada-Mori cultures were repeated; cure was defined as complete absence of eggs and/or larvae from stools tested 30 days after dosing. Ivermectin was well tolerated. Overall cure rates at all doses 30 days after therapy averaged 88% for strongyloidiasis, 100% for ascariasis, 85% for trichuriasis, and 85% for enterobiasis. Ancylostoma duodenale and Necator americanus were little affected.

Intestinal parasites are common among labourers from foreign countries and in immigrants. Some worm-infections like ascaridiasis or enterobiasis occur in children quite often even in the cold climates. In cases of ascaridiasis only a heavy infection causes clinical symptoms. The diagnosis is made through the detection of eggs in the stools, as all the other worm-infections are diagnosed from the stool-test. Piperazine-derivatives are highly effective against ascaris; another useful drug is Pyrantel-Pamoate. Toxocara canis, which affects normally only dogs, can occur occasionally in humans. Its larvae migrate in the body and cause granulomas. The main clinical symptom of threadworms (enterobiasis) is itching around the anus. This parasite can be eradicated through Pyrvinium-Pamoate. The first symptom a patient notices in cases of taeniasis are proglottides--parts of the worms--which are passed with the stools. The drug of choice against all kinds of tapeworms is Niclosamide. Hookworms are rampant in tropical countries. Heavy infections can cause severe anemias, especially in children. Bephenium-Naphthoate and Bitoscanate are effective drugs against this parasite. The whipworm (Trichuris trichura) is very common in the warm countries. It can be treated by Tiabendazole and nowadays also with Mebendazole, which is virtually atoxic. Infections with Strongyloides stercoralis are difficult to eradicate, as there are different ways of reinfection. In case an infection with strongyloides is accompanied by other serious diseases cachexia and even fatal outcome has been seen.

Although improved sanitation in the United States has resulted in a general diminution in the prevalence of intestinal parasitic infections, some, such as enterobiasis, are not reduced by improved environmental or water sanitation and others, such as amebiasis and hookworm infection, persist in foci. Other infections, notably giardiasis, have increased due to the travels of American tourists in other countries where environmental sanitation is poor. North American physicians, therefore, may expect at some time to have to treat parasitic infections. Favored chemotherapeutic agents currently are: for amebiasis--metronidazole and diiodohydroxyquin; for giardiasis--metronidazole; for tapeworm infections--niclosamide; for enterobiasis--pyrantel pamoate, piperazine citrate, or pyrvinium pamoate; for ascariasis--piperazine citrate; for stronglyoidiasis--thiabendazole; for trichuriasis--mebendazole; for hookworm infection--pyrantel pamoate; for schistosomiasis japonica--tartar emetic; and for schistosomiasis mansoni--niridazole.