Antiparasitic treatment of cerebral cysticercosis: lessons and experiences from China

Abstract

Cysticercosis is a tropical disease caused by infection with the larval stage of the pork tapeworm, Taenia solium. Humans and pigs acquire cysticercosis by ingesting T. solium eggs shed in the feces of humans with taeniasis (i.e., infected with an adult intestinal tapeworm). Cerebral cysticercosis occurs when the cysts of T. solium develop within the central nervous system, and it is the primary cause of illness in T. solium infection. Currently, cerebral cysticercosis is endemic worldwide, and it is a leading cause of adult-onset epilepsy in developing countries. However, it is now increasingly detected in developed countries due to the immigration of T. solium carriers from the endemic areas. The antiparasitic treatment of cerebral cysticercosis remains controversial till now. In China, except a few cases who conform to the contraindicated criteria of antiparasitic therapy, most cerebral cysticercosis patients with symptoms and signs are given etiological treatment. This paper reviews the antiparasitic therapy of cerebral cysticercosis in China during the past several decades. Praziquantel treatment with different regimens has been used, and various efficacies are achieved. In the early stage, unsatisfactory therapeutic efficacy was achieved due to small doses and short treatment courses. Afterwards, the therapeutic efficacy became increasingly remarkable in both adults and children with the increases in dosage and courses. Albendazole also presents activity against cysticercosis with slow and moderate action, and it has been widely used in the treatment of the infection. The comparison between praziquantel and albendazole treatments showed that the immediate and short-term effects of albendazole treatment were better than those of praziquantel treatment, but similar mid- and long-term efficacies were observed following albendazole and praziquantel treatments. The combination of albendazole and praziquantel treatments can increase the therapeutic efficacy, and now, from the massive clinical practices, most of Chinese clinical specialists propose the combination therapy of albendazole and praziquantel for cerebral cysticercosis with simultaneous administration of steroids, especially in the first course. In addition, administration of praziquantel at a high dose can become a diagnostic treatment for suspected cerebral cysticercosis and serve as a supplement of the currently available diagnostic methods, such as diagnoses based on the clinical features, immunology, CT and MRI imaging, etc., in some atypical cerebral cysticercosis patients. Praziquantel and albendazole treatments have some adverse reactions, and to control these adverse effects, all the cerebral cysticercosis patients should be treated in hospital. According to the type of cerebral cysticercosis, especially for intracranial hypertension type and meningocephalitis type, the dosages of anti-cysticercus drugs need to follow a gradually increasing pattern. During the period of anti-cysticercosis treatments, steroids and/or dehydrating agents need be administered which can alleviate the intracranial hypertension and so on. Traditional Chinese medicines have been also used in the treatment of cerebral cysticercosis and achieve satisfactory outcomes. However, the compound prescription of traditional Chinese medicines is very complex, and the effective components are not fully clear. Some cerebral cysticercosis patients with very high intracranial tension could not receive antiparasitic treatment immediately, and surgical treatment is required. Chinese surgeons also achieve some successful experiences, but not all the cysticercus can be removed completely during the surgery. Therefore, antiparasitic drugs are still needed after the operation. The rehabilitative treatment is supplementary in the therapy of cerebral cysticercosis. In China, the rehabilitative treatment of cerebral cysticercosis is still at the initial stage. These lessons and experiences in China can be shared with medical staff and researchers from other countries where the disease is endemic.