A Multicentric Study on the Clinical Profile, Serology, Neuroimaging and Treatment of Neurocysticercosis

Abstract

Introduction: Neurocysticercosis (NCC) is the most common parasitic disease affecting the human brain, and the leading infectious cause of seizures/epilepsy in India. It is often a diagnostic challenge due to varying clinical and imaging presentations. Aim: To describe the clinical profile, serological testing, imaging features and treatment outcomes of NCC, in an Indian population. Materials and Methods: This prospective observational study with a case control design was carried out over a period from June 2015 to June 2019, at two Tertiary Care Hospitals in Mumbai and Bangalore. Seventy four (74) cases who had evidence of parenchymal/extra-parenchymal NCC lesions based on Contrast MRI Brain (1.5 Tesla), were included in the study. Fifty matched controls with Idiopathic epilepsy were also recruited in the study, so as to establish the sensitivity and specificity of the commonly used ELISA test (IgG antibody) for NCC. All patients with viable parenchymal NCC lesions were given standard cysticidal therapy (Albendazole), along with anti-epileptic drugs, as per clinician discretion. Disability at six months follow-up was assessed using the modified Rankin Scale (mRS). Pearson’s Chi-square test was used to compare dependent variables. The p-values <0.05 were accepted as statistically significant. Results: Of the 74 cases with NCC enrolled in the study, 81% (60) were males and the mean age of the population was 36.4 years. Total 91% cases (68) presented with seizures. Neuro-imaging revealed majority of lesions were vesicular (28%). Total 42% (31/74) had Solitary Cystisercal Granuloma (SCG), only 26% (19/74) cases and 8% (4/50) controls were positive for the IgG anti-cysticercal antibody by ELISA. This gave the antibody test a sensitivity of 26%, and a specificity of 92%. This translated into a Positive Predictive Value (PPV) of 83%, Negative Predictive Value (NPV) of 45%, and a positive likelihood ratio of 3.21. In patients who had single or multiple viable parenchymal NCC lesions (57/74), cysticidal therapy with Albendazole (under steroid cover) was safe and effective in 88% (50/57) cases. Conclusion: NCC commonly presents with seizures, and is best diagnosed with contrast MR imaging of the brain. The commercially available ELISA based antibody test do not add significantly in the management of this tropical infection. Cysticidal therapy is safe and effective in a majority of the patients, however treatment of extra-parenchymal NCC remains a challenge.

Keywords

• albendazole
• enzyme linked immunosorbent assay
• inflammatory granuloma
• magnetic resonance imaging
• seizures