Hookworm infestation

Pyrantel is a dmg of first choice for the treatment of a number of round-, thread- and hookworm infestations. However, it has no activity against whipworm. Its mechanism of action is based on triggering the release of acetylcholine in helminths causing a depolarizing neuromuscular blockade that leads to spastic paralysis. 

Pathophysiologically, the normal red cell mass, reflected in haemoglobin level or packed cell volume, decreases in anaemia. The mandatory first step is to identify the cause for this change and correct it, wherever possible, prior to initiating treatment. It makes little sense only to replace iron in a patient who continues to rapidly loose blood from the gastrointestinal tract due to a heavy hookworm infestation or a resectable carcinoma of the caecum. Accordingly, it will be assumed throughout that a... 

Mebendazole is used primarily for the treatment of A. lumbricoides, T. trichiura, E. vermicularis, and hookworm infections, in which it produces high cure rates. It is an alternative agent for the treatment of trichinosis and visceral larva migrans. Owing to its broad-spectrum anthelmintic effect, mixed infections (ascariasis, hookworm infestation, or enterobiasis in association with trichuriasis) frequently respond to therapy. High doses have been used to treat hydatid disease, but albendazole is now thought to be superior. 

Albendazole (9.117), a benzimidazole carbamate, is a broad-spectrum oral antihelminthic used for cysticercosis, ascariasis, pinworm infestation, and hookworm infestation. It is thought to work by blocking microtubule synthesis in the nematode, subsequently impairing glucose uptake. 

Ascarlasis, ankylostomiasis and trichuriasis 400 mg single dose Taenlasis strongyloldosis 400 mg x 3 days Neurocysticercosis 15 mg/kg/dally x 1 month Hydatid disease 400 mg BD X 1 month (If required repeat after 2 wks). Trichinosis and strongyloldosis 25 mg/kg/day In two divided doses X 2 days after meal (If required repeat after 2 days) Ascarlasis and hookworm Infestation 50-150 mg single dose. Taenlasis 0.5-2 g (After breakfast 1 g to be chewed and swallowed with water followed by 1 g after 1 hr) For H. nana Infestation 2 g dose Is repeated dally for 5 days. 

Hookworm infestation (a major source of blood loss in many parts of the world, but not northern Europe). 

Balmer S, Howells G, Wharton B. The effects of tetrachlor-ethylene in children with kwashiorkor and hookworm infestation. J Trop Pediatr 1970 16(l) 20-3. 

The leaves of Maytenus senegalensis are used in East Afiica for hookworm infestations. In the Sudan, the antiplasmodial activity of M. senegalensis leaves and stem bark was reported (IC50 5.1 and 3.9 xg/ml respectively). Preliminary phytochemical analysis of the dichloromethane fraction of M. senegalensis revealed terpenoids and traces of phenolic principles. The antiplasmodial activity of Maytenus spp. is promising. The survival time was similar to that of CQ (p > 0.05). ... 

One human death has been reported following oral treatment with 3 mL (152 mg/kg) of tetrachloroethylene for hookworm infestation (Chaudhuri and Mukeqi 1947). This individual was a severely emaciated "street beggar" with preexistent chronic malnutrition and septic cholecystitis thus, it is difficult to determine the specific cause of his death and the relevance of this death to healthy humans. 

The effect of hookworm infestation on vitamin A is controversial. Reports from Puerto Rico (Sheehy et al.y 1962) and north India (Tandon et al.y 1966) suggest that malabsorption may occur, but this was not found among Africans in Uganda (Banwell et al.y 1967). Banwell et al. (1967) suggest that the discrepancy in findings may be due to an underlying tropical sprue that is endemic in Puerto Rico and India but is an extremely rare disease in Africa. 

The major representative drugs are pyrantel, morantel and oxantel (Figure 12.8). Oxantel is a more recent member of the group. Pyrantel and oxantel are used in human patients. Pyrantel is used in the treatment of pinworm, roundworm and hookworm infestations and is valued because of its very low human toxicity. Oxantel is used for the treatment of whipworm (trichuriasis) for which pyrantel is ineffective. Morantel is closely related in chemical structure to pyrantel (see Figure 12.8) but it does not appear to have been extensively used in human medicine. 

The drug of choice for nematode infestations (hookworm, enterobiasis, and ascariasis) is mebendazole, while ivermectin is indicated for strongyloidiasis and praziquantel is indicated for tapeworms. 

Mebendazole is a broad-spectrum anthelmintic drug producing high cure rates in infestations by Ascaris, threadworms, hookworms, and whipworms. The drug is practically insoluble in water and... 

Iron-deficiency anaemia is the most common type of anaemia. Red blood cells often appear hypochromic (paler than usual) and microcytic (smaller than usual). Iron-deficiency anaemia is caused by insufficient dietary intake or absorption of iron, or by loss of blood, for example bleeding lesions of the gastrointestinal tract. Worldwide the most common cause of iron-deficiency anaemia is parasitic infestation (hookworm, amoebiasis, schistosomiasis and whipworm). 

Parasitic Infestations. Blood loss attributable to parasitic diseases may contribute to conditioned deficiency of zinc. Such appears to have been the case in the zinc responsive "dwarfs reported from Egypt (6,7), As red blood cells contain 12-14 /xg of Zn/mL, infections with hookworm and/or schistosomiasis which are severe enough to cause iron deficiency will probably contribute to the occurrence of zinc deficiency. 

Albonico et al. (1998) mentioned that the hookworms, Ancylostoma duodenal and Necator americanus caused significant gastrointestinal blood loss. However, they had no evidence that endemic A. duodenal infestation had a greater impact on the Fe status of populations than an N. americanus infestation. As a result, they decided to do a study with a sample of 525 schoolchildren in Pemba Island, Tanzania, and compare the degree of anemia and ID associated with the two hookworm species at the individual and community... 

The iron deficiency and helminth infestation are two of the most common conditions afflicting children in iess industriaiized countries. Hookworm species being transmitted in a community influence the burden of iron deficiency anemia and should be considered when prioritizing and planning programs for hookworm and anemia control. 

In an intervention study with schoolchildren 8—10 years old in Malawi, Furnee et al. (1997) examined the relationship of intestinal parasite treatment and oral iodized oil efficacy. Severely iodine-deficient schoolchildren with a single parasitic infestation, either A. lumbricoides (n = 44), hookworm (n = 42), or Entamoeba histolytica (n = 24), were randomly allocated to receive or not receive treatment before taking a 1ml oral supplement (490 mg Iodine) of iodized ethyl esters from poppyseed oil. After supplementation, urinary iodine concentrations were measured regularly, to define time intervals indicating moderate iodine deficiency before urinary iodine concentrations returned to 0.40 mmol/1. Treatment with metronidazole for E. histolytica increased the protection period from 2.0 to 21.0 weeks P < 0.05). For all untreated children, the duration effect was 9.2 weeks shorter P < 0.001) than for their treated peers (16.8 weeks). They concluded that, by interfering with absorption, intestinal parasitic infestations reduce the efficacy of oral supplementation with iodized ethyl esters (Table 52.8). 

The two most widespread types of hookworm in humans are the American hookworm (Necator americanus) and the Old World hookworm (Ancylostoma doudenale). The life cycles of both are similar. The larvae are found in the soil and are transmitted either by penetrating the skin or being ingested orally. The circulatory system transports the larvae via the respiratory tree to the digestive tract, where they mature and live for 9 to 15 years if left untreated. These worms feed on intestinal tissue and blood. Infestations cause pulmonary lesions, skin reactions, intestinal ulceration, and anemia. The worms are most prevalent in regions of the world with temperatures of 23 to 33°C, abundant rainfall, and well-drained, sandy soil. 

Another major use of tetrachloroethylene is as a vapor and liquid degreasing agent. Since tetrachloroethylene dissolves many organic compounds, select inorganic compounds, and high-melting pitehes and waxes, it can be used to clean and dry contaminated metal parts and other fabricated materials. It is also used to remove soot from industrial boilers (Verschueren 1983). Tetrachloroethylene has been used as an anthelmintic in the treatment of hookworm and some nematode infestations, but it has been replaced by drugs that are less toxic and easier to administer (Budavari 1989 HSDB 1996). 

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