Human neurocysticercosis : Comparison of different diagnostic tests in cerebrospinal fluid 1 2

25 Neurocysticercosis (NC), caused by the larval stage of Taenia solium, is one of the most 26 common parasitic diseases of the central nervous system. NC diagnosis is mostly based on 27 costly brain neuroimaging (computed tomography and/or nuclear magnetic resonance) that is 28 rarely accessible in most affected areas. The most sensitive and specific tools for NC 29 diagnosis are imagery techniques. The identification of specific antibodies and antigens are 30 currently used only to support NC diagnosis due to their limited specificity and sensitivity. 31 This study was performed to compare immunodiagnostic assays (antibody detection by 32 ELISA and EITB and HP10 antigen detection by ELISA) with the detection of parasite DNA 33 by PCR amplification of a repetitive element of the parasite genome in the cerebrospinal fluid 34 (CSF) of 121 radiological and clinically characterized NC patients. Patients were divided into 35 six groups according to the stage of parasites and their localization. CSF cellularity of each 36 patient was also recorded. 37 When all patients were considered, PCR exhibited the highest sensitivity (95.9%) and 38 variable specificity (80% or 100%) depending on the controls used. Sensitivity of antibody 39 detection by ELISA and EITB was not significantly different and ELISA identified HP10 40 antigen mostly when vesicular cysticerci were located in the subarachnoideal basal cisterns. 41 These results can help in the selection of different individual assays or their combination to be 42 used in NC diagnosis according to different requirements. 43