A case of Bilharzial tubercle in a migrant from zimbabwe, diagnosed late through cystoscopy and histology, with negative schistosomiasis serology [Indirect Hemagglutination (IHA)]

Abstract

Aim: To evaluate clinical usefulness of metagenomics sequencing alongside conventional testing in two adult cases of CNS infection. Methods: For both cases, bacterial microscopy and culture, herpes multiplex PCR, enterovirus PCR, parasitology multiplex PCR, Acanthamoeba culture, fungal culture, cryptococcal antigen and M. tuberculosis culture and PCR were done on the cerebrospinal fluid (CSF) with 4 mL required for each patient. Metagenomics sequencing required only 0.4 mL of CSF for each patient. CSF was subjected to particle enrichment (virus and ribosomes), random amplification of extracted RNA and DNA, library preparation and Ion Torrent next generation sequencing (NGS). Although clearly an experimental method, this method has been successful in detecting viruses and other microbes in a range of samples. Result: All conventional testing as mentioned above was negative. NGS of sample 1 generated 3.7 million reads, mean read length 156 nucleotides; sample 2 generated 4 million reads, mean read length 185 nucleotides. Analysis of NGS reads focusing on finding an infectious aetiology, did not reveal any significant findings. Clinicians were reassured to prescribe immune-suppressive therapy with good response for Case 1 and have antibiotics ceased in Case 2. Conclusion: Metagenomics sequencing alongside conventional testing may be useful for ruling out active infection in patients with possible CNS infection.