Pediatric neurocysticercosis: usefulness of antibody response in cysticidal treatment follow-up.

Serum and urine samples were collected from 33 NCC patients before the albendazole treatment, 3-6 and 12 months PT. At 3 months PT, 24 (72.7%) patients had no detectable CT/MRI lesions and 9 (27.2%) patients had persistent lesions. Antibody response to crude soluble extract (CSE), excretory secretory (ES), and lower molecular mass (LMM) (10-30 KDa) antigenic fraction of T. solium cysticerci was detected in serum and urine samples by ELISA. Before the treatment, out of 33 NCC children, 14 (42.4%), 22 (66.6%), and 11 (33.3%) serum samples were found positive with the use of CSE, ES, and LMM antigen, respectively. At 3-6 months PT, positivity rate was 5 (15.1%), 2 (6%), and 4 (12.1%) and at 12 months PT, positivity rate was 5 (15.1%), 0, and 3 (9%) with the use of CSE, ES, and LMM antigen, respectively. There was no significant difference in the positivity with the use of three antigens in pretreatment and PT urine samples. The study suggests that the use of ES antigen to detect antibody in serum samples may serve better purpose to evaluate the therapeutic response in patients with NCC.

Urine antigen detection for the diagnosis of human neurocysticercosis.

Neurocysticercosis (NCC) is a major cause of seizures and epilepsy. Diagnosis is based on brain imaging, supported by immunodiagnosis in serum or cerebrospinal fluid (CSF). Lumbar puncture is invasive and painful. Blood sampling is slightly painful and poorly accepted. Urine antigen detection has been used for other parasites and tried in NCC with suboptimal performance. We used a monoclonal antibody-based ELISA to detect Taenia solium antigens in urine from 87 Peruvian neurocysticercosis patients (viable cysts, N = 34; subarachnoid cysticercosis, N = 10; degenerating parasites, N = 7; calcified lesions, N = 36) and 32 volunteers from a non-endemic area of Peru. Overall sensitivity of urine antigen detection for viable parasites was 92%, which decreased to 62.5% in patients with a single cyst. Most patients (30/36, 83%) with only calcified cysticercosis were urine antigen negative. Antigen levels in paired serum/urine samples (evaluated in 19 patients) were strongly correlated. Non-invasive urine testing for T. solium antigens provides a useful alternative for NCC diagnosis.

Enantioselective renal excretion of albendazole metabolites in patients with neurocysticercosis.

The present study investigates the urinary excretion of the enantiomers of (+)- and (-)-albendazole sulfoxide (ASOX) and albendazole sulfone (ASON) in 12 patients with neurocysticercosis treated with albendazole for 8 days (7.5 mg/kg/12 h). Serial blood samples (0-12 h) and urine (three periods of 8 h) were collected after administration of the last dose of albendazole. Plasma and urine (+)-ASOX, (-)-ASOX, and ASON metabolites were determined by HPLC using a chiral phase column (Chiralpak AD) with fluorescence detection. The pharmacokinetic parameters (P < 0.05) for (+)-ASOX, (-)-ASOX, and ASON metabolites are reported as means (95% CI); amount excreted (Ae) = 3.19 (1.53-4.85) vs. 0.72 (0.41-1.04) vs. 0.08 (0.03-0.13) mg; plasma concentration-time area under the curve, AUC(0-24) = 3.56 (0.93-6.18) vs. 0.60 (0.12-1.08) vs. 0.38 (0.20-0.55) microg x h/ml, and renal clearance Cl(R) = 1.20 (0.66-1.73) vs. 2.72 (0.39-5.05) vs. 0.25 (0.13-0.37) l/h. Sulfone formation capacity, expressed as the Ae ratio ASON/ASOX + ASON, was 2.21 (1.43-2.99). These data point to enantioselectivity in the renal excretion of ASOX as a complementary mechanism to the metabolism responsible for the plasma accumulation of (+)-ASOX. The results also suggest that the metabolite ASON is partially eliminated as a reaction product of the subsequent metabolism.