Metagenomic next-generation sequencing in the diagnosis of neurocysticercosis: A case report

Figure 1 Imaging examinations results. A: Magnetic resonance arteriography image revealing partial vascular stenosis and weakened blood flow signal; B-D: Cerebral magnetic resonance imaging (MRI) showing a cystic lesion, an expanded ventricular system and hydrocephalus. T1-weighted image showing a low signal of the corpus callosum (B); T2-weighted image showing a high signal behind the corpus callosum (C); Fast fluid attenuated inversion recovery sequence of brain MRI revealing a cystic lesion in the corpus callosum (D); E and F: Cerebral MRI image with contrast showing several small hyperintense lesions involving the brain parenchyma and ventricular system, with subtle ring enhancement of gadolinium.

Figure 2 he diagnosis of Taenia solium by metagenomic next-generation sequencing. A: Mapping of Taenia solium reads on the genome; B: Reads distribution of total DNA in the cerebrospinal fluid sample. A total of 21507137 (21 M) reads were obtained from metagenomic next-generation sequencing, among which 65792 reads were matched with microorganisms; C: Distribution of pathogenic microorganisms reads in the absence of human, others, and unclassified reads; 43134 reads correspond to pathogenic parasite DNA. Among them, 94.38% (40710 reads) map to the Taenia solium genome.

Figure 3 The timeline of clinical events. Imaging examinations from the local hospital, taken seven days before admission, showing hydrocephalus. The patient was treated with mannitol. Before metagenomic next-generation sequencing (mNGS) was conducted (the first five days of the hospital stay), we considered this to be a central nervous system infection case. On the fifth day of the hospital stay, we obtained the mNGS results which showed high Taenia solium reads. Symptomatic treatments were carried out combining dexamethasone and albendazole; meanwhile, glycerol fructose and lappaconitine were used to relieve the symptoms. Blood means the Blood specimen. CSF means the cerebrospinal fluid specimen. MRI: Magnetic resonance imaging; WBC: White blood cell; N: Neutrophils; L: Lymphocyte; B: Basophilic granulocyte; E: Eosinophilic granulocyte; PLT: Platelets; PCT: Procalcitonin; CRP: C-reactive protein; Na: Sodium; K: Potassium; Cre: Creatinine; TORCH: Antibody test for Toxoplasma, Herpes virus, Cytomegalovirus, and Rubella virus; CSF: Cerebrospinal fluid; mNGS: Metagenomic next-generation sequencing; ANA: Antinuclear antibody. -: Normal; ↑: Above normal; ↓: Below normal.