Search

Background: The morbidity and mortality of extraparenchymal neurocysticercosis (EP-NC) remain high and effectiveness of current medical treatment is suboptimal. Various factors have been implicated in the severity of EP-NC and in the poor response to treatment, but the possible role of host immune and endocrine systems has not yet been examined thoroughly. Methodology/Principal findings: 42 participants with EP-NC before receiving standard treatment and 25 healthy controls were included in the study. Treatment response was assessed by comparing pre/post treatment parasite volumes from 3D MRI. Prior to treatment among participants with EP-NC, specific stimulation induced an increased specific proliferative response accompanied by a significant increase in IL-4, NK, NKT, Bregs and Tregs cells, whereas in healthy controls, specific stimulation induced a significant increase in IL-1β, IL-5, CCL5, IL-6, TNF-α, NK and Bregs cells. Significant differences between participants with EP-NC and healthy controls in the specific inflammatory response were observed. Participants with EP-NC prior to treatment had significantly weaker responses of proinflammatory cytokines (IL-6, TNF-α) and NK cells, and stronger IL-4 response. Anthelmintic treatment did not promote significant peripheral immunological changes at any time, although inflammation was sustained in the cerebrospinal fluid. Serum estradiol concentration significantly decreased after anthelmintic treatment among males, and cortisol correlated negatively with IL-6 and positively with IFN-γ levels. No pre-treatment immunologic or endocrinologic parameters were significantly associated with response to treatment. Conclusion/Significance: Prior to anthelmintic treatment, EP-NC was characterized by low lymphocyte reactivity accompanied by a regulatory response, which may be involved in the lack of peripheral immunological changes during and after treatment, although a central inflammatory response was present. This weak specific peripheral response could favor the chronicity of the infection and the poor response to treatment. Our findings highlight the need for new anti-inflammatory treatment focused on the central nervous system with less systemic immunosuppressive effects. Author summary: Neurocysticercosis is a central nervous system infection with the helminth Taenia solium in its larval stage. It is a marker of poverty and remains endemic in countries of Latin America, Africa, and Asia. The severity of neurocysticercosis and the prognosis of patients depend on the location of the parasites. Extraparenchymal infection involving the subarachnoid and/or ventricular space is associated with high morbidity and mortality and a suboptimal response to current anthelminthic treatment regimens. We examined peripheral immunological parameters and hormones of 42 participants with extraparenchymal neurocysticercosis before and after treatment, and their associations with subsequent treatment response. Prior to treatment, compared with healthy controls, there was low lymphocyte reactivity with a regulatory response, which may explain the lack of peripheral immunological changes during and after treatment. This weak specific peripheral response could favor the chronicity of the infection and the poor response to treatment and should be considered in research to improve patient outcomes. [ABSTRACT FROM AUTHOR]