Identification of Taenia solium DNA by PCR in blood and urine samples from a tertiary care center in North India.

BACKGROUND: NCC is a neglected zoonotic disease with high endemicity and disease burden. Neurocysticercosis is a frequent cause of seizures in endemic countries. Early diagnosis and therapy helps in reducing morbidity and DALYs (daily adjusted life years) lost. Definite diagnosis still relies on neuroimaging identification of scolex or by histopathological examination. Molecular method such as PCR (Polymerase Chain Reaction) is an emerging modality to supplement or complement these Gold standard methods. AIM: To determine the utility of PCR in detecting Taenia Solium DNA in NCC patients. METHODS: A total of 100 blood samples of cases of NCC and 50 control blood samples, 58 urine samples of NCC cases and 24 control samples were collected. Repetitive element PTsol9 of the Taenia Solium was targeted. RESULTS: The sensitivity and specificity of PCR in blood samples was 57% and 94%, while sensitivity and specificity in urine samples was 64% and 87%. CONCLUSION: PCR assay can be used as an adjunct for the diagnosis of NCC especially in ambiguous cases, this is relatively rapid and non-invasive diagnostic modality.

Sorting out difficulties in immunological diagnosis of neurocysticercosis: Development and assessment of real time loop mediated isothermal amplification of cysticercal DNA in blood.

PURPOSE OF THE STUDY: Among various immunological tests available for diagnosis of neurocysticercosis (NCC), only EITB (Electroimmunotransfer blot for detection of anticysticercal antibodies) had gained widespread acceptance. However EITB is not available widely and is costly (Indian rupees 15,000/- approximately). We evaluated utility of Loop mediated isothermal amplification (LAMP) assay for detection of Taenia solium cox1 gene in blood of patients with NCC. PATIENTS AND METHODS: Current study included 100 consecutive patients of NCC at a tertiary teaching hospital in Northern India. All the patients underwent detailed history and examinations as well as gadolinium enhanced magnetic resonance imaging of brain. LAMP assay was performed in all the patients. The results were compared with 50 controls. RESULTS: LAMP detected Taenia Solium cox1 gene in 74% of all blood samples in patients of NCC.T he overall sensitivity of LAMP assay for detection of cox1 gene was 74% in all patients with NCC, 71.8% in patients with intraparenchymal brain cysts only and 86.7% of patients with extraparenchymal brain cysts with or without intraparenchymal brain cysts. The overall specificity of LAMP assay was 90% in all these three subgroups. The positive predictive value of real time LAMP assay was close to 93% for almost all forms of NCC- both solitary and multiple while negative predictive value ranged from 57 to 64%. CONCLUSION: Real time LAMP assay of blood for detection of Taenia solium cox1 gene appears to be a promising toll for diagnosis of NCC.