Real Time Loop Mediated Isothermal Amplification Assay of Urine for Diagnosis of Neurocysticercosis: A Preliminary Observation Study

Abstract

Objectives: Neurocysticercosis (NCC) is one of the commonly Neglected tropical disease worldwide. Improvement in Living conditions with better diagnostics can reduce the incidence of this disease. The burden of NCC is high in areas with poor socio-economic development. Despite high prevalence in India, the diagnostic challenge remains especially when differentiating from tuberculosis which is also common in the same setting. We describe a novel and rapid diagnostic method for NCC, which might add to our diagnostic Repertoire. Methods: It was prospective case control study involving consecutive patients of definite and probable NCC at a tertiary teaching hospital in Northern India. LAMP assay in urine was performed in all the patients. LAMP amplified target Taenia solium cox1 gene at 60ºC in 120min. The results were compared with 24 controls. The specificity, sensitivity, positive predictive value and negative value were calculated using a 2X 2 contingency table. Results: Total of 58 patients recruited, 53 were definitive NCC and 5 had probable NCC based on Del Brutto criteria and 24 volunteers were taken as control all of them underwent urine LAMP of Taenia solium. Taenia solium cox1 gene was detected in 60% of Urine samples in patients of NCC, overall specificity of LAMP assay was 92%. The negative predictive value and positive predictive value of real time LAMP assay was 50% and 95%. Conclusions: Conclusion: Real time urine LAMP assay for Taenia solium gene offers noninvasive, cost effective and rapid method to detect Taenia parasite in patients, in Addition to available investigations. Specially in resource limited setting of endemic countries. J Microbiol Infect Dis 2020; 10(3):154-159.

Keywords

• Loop mediated isothermal amplification
• Taenia solium
• cox1 gene
• Neurocysticercosis
• Urine

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