A major unresolved question is how to treat on going and/or treatment induced inflammation to degenerating T. solium cysts. No randomized studies have been performed to determine the need and dosing of corticosteroids in the treatment of parenchymal neurocysticercosis. Antiparasitic treatment of brain cysts leads to seizures due to the hosts inflammatory reaction, requiring concomitant steroids. Our group hypothesized that increased steroid dosing will reduce treatment-associated seizures. We performed an open-label randomized trial comparing 6 mg/d dexamethasone for 10 days (conventional) with 8 mg/d for 28 days followed by a 2 week taper (enhanced) in neurocysticercosis patients receiving albendazole. Follow up included active seizure surveillance and brain imaging. Study outcomes were seizure days and patients with seizures, both measured in days 11-42. Additional analyses compared days 1-10, 11- 21, 22-32, 33-42, 43-60, and 61-180. Thirty-two individuals were randomized into each arm, two did not complete follow up. From days 11 to 42, 59 partial and 6 generalized seizure days occurred in 20 and 2 versus 4 generalized seizures, p=0.624). The numbers of patients with seizures in this period showed similar non-significant differences. In the enhanced steroid arm there were significantly fewer days and individuals with seizures during antiparasitic treatment (days 1-10: 4 versus 15, p=0.016, and 1 versus 8, p=0.013, number needed to treat 4.6, relative risk 0.13, 95%CI: 0.02 0.94) and early after dexamethasone cessation (days 11-21: 6 versus 25, p=0.017, and 4 versus 12, p=0.021, NNT 4.0, RR 0.33, 95%CI: 0.12 0.92) but not after day 21. There were no significant differences in antiparasitic efficacy or relevant adverse events. We concluded that increased dexamethasone dosing results in fewer partial seizures for the first 21 days during and early after antiparasitic treatment for viable parenchymal neurocysticercosis but not during the first 11-42 days, which was the primary predetermined time of analysis (Garcia HH, Gonzales I, Lescano AG, Bustos JA, Pretell EJ, Saavedra H, et al. Enhanced steroid dosing reduces seizures during antiparasitic treatment for cysticercosis and early after. Epilepsia. 2014;in press) We previously reported the histopathology from a person with a calcified T. solium cyst undergoing repeated episodes of perilesional edema and seizures. We record the histopathology of a second case. Similar to our first case report, the current case demonstrated a degenerating cyst with the calcification likely due to aggregatation of calcareous corpuscles. Both cases contrasted with the few descriptions of the histopathology of calcifications reported in older literature, presumably not associated with seizures or perilesional edema. These showed amorphous calcification and sparse inflammation. From the few cases in the literature, the histopathology of calcifications differ and may reflect why perilesional edema is found in some patients and not in others with calcifications not undergoing perilesional edema episodes(Nash TE, Bartelt LA, Korpe PS, Lopes B, Houpt ER. Case Report: Calcified Neurocysticercus, Perilesional Edema, and Histologic Inflammation. American Journal of Tropical Medicine and Hygiene. 2014;90(2): 318-21.) Albendaozle is the drug of choice to treat neurocysticercosis. It is an enantiomere consisting of mixture of two forms. In our laboratory in Peru we showed that the (+)-(R)-Albendazole Sulfoxide is the Active Enantiomer against Taenia solium. Racemic albendazole sulfoxide is composed of ABZSO (+)-(R)- and (-)-(S) enantiomers that have been shown to differ in pharmacokinetics and activity against other helminths. The antiparasitic activities of racemic ABZSO and its (+)-(R)- and (-)-(S) enantiomers against T. solium cysts were evaluated in vitro. Parasites were collected from naturally infected pigs, cultured, and exposed to the racemic mixture or to each enantiomer (range, 10 to 500 ng/ml) or to praziquantel as a reference drug. The activity of each compound against cysts was assayed by measuring the ability to evaginate and inhibition of alkaline phosphatase (AP) and parasite antigen release. (+)-(R)-ABZSO was significantly more active than (-)-(S)-ABZSO in suppressing the release of AP and antigen into the supernatant in a dose- and time-dependent manner, indicating that most of the activity of ABZSO resides in the (+)-(R) enantiomer. Use of this enantiomer alone may lead to increased efficacy and/or less toxicity compared to albendazole(Paredes A, Lourenco TD, Marzal M, Rivera A, Dorny P, Mahanty S, et al. In Vitro Analysis of Albendazole Sulfoxide Enantiomers Shows that (+)-(R)-Albendazole Sulfoxide Is the Active Enantiomer against Taenia solium. Antimicrobial Agents and Chemotherapy. 2013;57(2):944-9.) .
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