Circulating cell-free DNA as a biomarker for molecular diagnosis of Neurocysticercosis

Abstract

Taenia solium is a widespread zoonotic tapeworm that predominantly affects regions of Latin America, South and South-East Asia, and Sub-Saharan Africa. Neurocysticercosis (NCC), the presence of T. solium cysts in the brain is associated with diverse clinical manifestations, such as epilepsy, seizures, and neurological deficits. It is a significant cause of preventable epilepsy globally, accounting for approximately 30% of cases in endemic regions. The diagnosis of neurocysticercosis relies on neuroimaging techniques, but these resources are often limited in low-income countries, resulting in an underestimation of the disease burden. The present study enrolled 141 patients who were clinically suspected and radiologically confirmed for NCC at the Neurology OPD of PGIMER, Chandigarh. Additionally, 98 control subjects attending the PGIMER OPD for investigation were also included. Plasma and urine samples were collected from all participants for further analysis. Cell-free DNA extraction was performed using specific kits, and the quality of the extracted DNA was assessed. The RT-LAMP assay targeted the cox1 gene. Real-time RT-LAMP results were evaluated using a fluorescence graph obtained with the Genei III fluorimeter. Among a group of patients diagnosed with NCC, the gene was identified in 74.4% of plasma samples and 67.3% of urine samples. In comparison, the T. solium cox1 gene was found in 6.1% of control subjects in plasma and urine samples using the LAMP assay. In conclusion, the study emphasises the need for improved diagnostic methods for NCC and presents promising alternatives, such as RT-LAMP and urine-based cell-free DNA analysis. These approaches offer advantages in terms of cost-effectiveness, simplicity, and diagnostic accuracy.

Keywords: Cell-free DNA; Diagnosis; LAMP; Molecular diagnosis; Neurocysticercosis.