Cestode infections treatment

Agents used in the treatment of cestodal infections include praziquantel (see Section Vll.a.l), niclosamide and the benzimidazoles such as albendazole and mebendazole (see Section vn.b.l). Niclosamide and praziquantel are effective against Taenia solum (pork tapeworm). Taenia saginata (beef tapeworm). Taenia latum (fish tapeworm) and Hymenolepis nana (dwarf tapeworm). Praziquantel is a second choice drug after albendazole for cys-ticercosis caused by Taenia solum. Albendazole and mebendazole are alternatives. 

Praziquantel is effective in the treatment of schistosome infections of all species and most other trematode and cestode infections, including cysticercosis. The drug s safety and effectiveness as a single oral dose have also made it useful in mass treatment of several infections. 

Fenbendazole (18) This drug shows high activity against Moniezia spp. in sheep (5-25 mg/kg) and calves (10-15 mg/kg) and, therefore, finds wide usage in the treatment of major nematode and a few cestode infections in above animals [176]. At a dose of 100 mg/kg, both fenbendazole and oxfendazole had no lethal effects on 10 week old cysticerci of T. saginata in calves [189]. 

Although a number of salicylanihde anthelmintics have been developed, most of them find use in the treatment of cestode and trematode infections in domestic animals. Niclosamide (4) is the only drug which has been extensively used to cure cestode infections in human. 

Answer D. Praziquantel is the drug of choice for treatment of all fluke (trematode) infections and most tapeworm (cestode) infections. Its antihelminthic action derives from an increase in membrane permeability to Ca, which results in contraction, followed by paralysis, of worm musculature. Mebendazole also has antihelminthic activity, hut it is restricted to the nematodes. The other drugs listed are antiprotozoals. 

The four medically important cestodes are Taenia saginata (beef tapeworm), Taenia solium (pork tapeworm, which can cause cysticerci in the brain and the eyesj, Diphyllobothrium latum (fish tapeworm), and Echinococcus granulosus (dog tapeworm, which can cause hydatid cysts in the liver, lungs, and brain). The primary drugs for treatment of cestode infections are praziquantel (see above) and niclosamide. 

More then a dozen representatives of the above ring systems were introduced into the human therapy. Actisomide (2) and trequinsin (3) are used as antiarrhytmic and antihypertensive agents, respectively. Sunepitron (4), a a 2-adrenoceptor antagonist, is under clinical trials for the treatment of anxiety and depression. Representatives of the third generation of antibacterial quinolone-3-carboxylic acids the blockbluster ofloxacin (5), its levorotatory enantiomer, levofloxacin (6), and rufloxacin (7) have gained wide acceptance for the treatment of bacterial infections of the respiratory and urinary tracts, skin, and soft tissues, as well as sexually transmitted diseases, and pazufloxacin (8) is under development. Praziquantel (9) is widely applied for the treatment of schistosomes- and cestode-caused infection in both veterinary and human therapies (Scheme 4). 

Several benzimidazoles are in use for the treatment of helminthic infections. Three of these, mebendazole, thiabendazole and albendazole, are described in this section. They have a broad range of activity against many nematode and cestode parasites, including cutaneous larva migrans, trichinosis, disseminated strongyloidiasis, and visceral larva migrans. A fourth, triclabendazole, is considered as the drug of choice for Easciola hepatica therapy. 

Praziquantel (9.124), a synthetic isoquinoline-pyrazine derivative, is effective for the treatment of schistosome infections it is also effective against trematode and cestode infestations. This agent increases membrane permeability to Ca + in the nematode, causing paralysis, dislodgement, and death of the worm. 

Several other heterocyclic compounds are used as veterinary anthelmintics although they lack the spectrum of activity of the above classes. For example, the antischistosomal drug, praziquantel (14), is highly effective in the treatment of cestodes in animals and man. The piperazine-derived drug diethylcarbamazine (15a) is used as a filaricide and for treatment of lungworm infections in sheep and cattle. The mode of action of diethylcarbamazine (13a) is uncertain but recent studies suggest that an effect on the helminth cuticle may be important. 

Albendazole (Albenza) is primarily used to treat infections caused by the larval form of certain cestodes (tapeworms). These infections often cause cysts (hydatid disease) in the liver, lungs, and other tissues albendazole is used as an adjunct to the surgical removal of these cysts or as the primary treatment if these cysts are inoperable. This drug is also effective against many gastrointestinal roundworms and hookworms, and is typically used as a secondary agent if other anthelmintics are not effective in treating these infections. 

Verruculotoxin (23) is produced by the fungus Penicillium verruculosum Peyronel. Praziquantel (24) is widely applied for the treatment of schistosomes- and cestode-caused infections in both veterinary and human therapies. Other compounds of these ring systems have aroused much interest owing to their valuable pharmacological properties. 

Praziquantel (biltricide, distocide) is a pyrazinoisoquinoline derivative. Infections with many different cestodes and trematodes respond favorably to this agent, whereas nematodes generally are unaffected. Praziquantel treatment of patients coinfected with schistosomes and hookworms reduces hookworm prevalence and infection intensities (egg counts) significantly. 

Low doses of praziquantel can be used successfully to treat intestinal infections with adult cestodes (e.g., a single oral dose of 25 mg/kg for H. nana and 10—20 mg/kg for D. lamm, T. sagi-nata, or T. soUum). Retreatment after 7—10 days is advised for individuals heavily infected with H. nana. While albendazole is preferred for therapy of human cysticercosis, the tissue infection with intermediate cyst larvae of T. soUum, prolonged high-dose therapy with praziquantel remains an alternative treatment. Neither the cystic nor alveolar hydatid diseases caused by larval stages of Echinococcus tapeworms respond to praziquantel here, too, albendazole is effective. 

Identify the drugs of choice for treatment of common infections caused by nematodes, trematodes, and cestodes. 

Clinical use Niclosamide is one of two drugs of choice (with praziquantel) for infections caused by beef, pork, and fish tapeworm infections. However, it is not effective in cysticer-cosis (for which albendazole or praziquantel is used) or hydatid disease caused by Echinococcus granulosus (for which albendazole is used). Scoleces and cestode segments are killed, but ova are not. Niclosamide is effective in the treatment of infections due to small and large intestinal flukes. 

Pyrantel pamoate is equivalent to mebendazole in the treatment of pinworm infections, but it is not effective in the treatment of infections caused by cestodes. The answer is (D). 

It is widely used across the globe for the management and treatment of intestinal nematode infection. It is also quite effective as a single-dose-treatment for ascariasis, New and Old World hookworm infections, and trichuriasis. It has been observed that a recommended multi-dose therapy with albendazol may help in the complete eradication of pinworm, threadworm, capillariasis, chlonorchiasis, and hydated disease as well. However, the overall observed effectiveness of albendazole against tapeworms (cestodes) is obviously more variable and less impressive apparently. 

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