Next generation sequencing for diagnosis of central nervous system aspergillosis in liver transplant recipients

A case report of diagnosis and dynamic monitoring of Listeria monocytogenes meningitis with NGS

Listeria monocytogenes (LM) infections of the central nervous system are deadly and have vague symptoms. Traditional cerebro spinal fluid culture has a low positive rate, and because antibiotic use is common following therapy, it is more challenging to assess the response from pathogen content. In this case, a 66-year-old man who had a fever, a headache, and vomit was admitted to the hospital. He had diabetes, decline in thyroid function, and a history of pituitary tumor removal surgery. His initial treatment with ribavirin, ceftriaxone antibiotic, and moxifloxacin did not go well. Using two etiological tests (culture and metagenomic next-generation sequencing [mNGS]), his cerebrospinal fluid tested positively for LM. Ampicillin-sulbactam and meropenem were used as treatments once LM meningitis was identified. After treatment, his cerebrospinal fluid was assessed once more. Culture: negative; targeted next-generation sequencing (tNGS): positive and shows changes in the copy number of the LM. After 44 days of treatment, the patient finally stopped taking antibiotics, and the prognosis was good. Our study showed that mNGS and tNGS, as novel approaches for pathogen detection, are capable of identifying pathogens quickly, sensitively, and accurately, especially when there are few infections present (such as after antibiotic treatment). The two methods can be a powerful assistance for helping clinicians to choose the best course of action.

A consensus conference to define the utility of advanced infectious disease diagnostics in solid organ transplant recipients

The last decade has seen an explosion of advanced assays for the diagnosis of infectious diseases, yet evidence-based recommendations to inform their optimal use in the care of transplant recipients are lacking. A consensus conference sponsored by the American Society of Transplantation (AST) was convened on December 7, 2021, to define the utility of novel infectious disease diagnostics in organ transplant recipients. The conference represented a collaborative effort by experts in transplant infectious diseases, diagnostic stewardship, and clinical microbiology from centers across North America to evaluate current uses, unmet needs, and future directions for assays in 5 categories including (1) multiplex molecular assays, (2) rapid antimicrobial resistance detection methods, (3) pathogen-specific T-cell reactivity assays, (4) next-generation sequencing assays, and (5) mass spectrometry-based assays. Participants reviewed and appraised available literature, determined assay advantages and limitations, developed best practice guidance largely based on expert opinion for clinical use, and identified areas of future investigation in the setting of transplantation. In addition, attendees emphasized the need for well-designed studies to generate high-quality evidence needed to guide care, identified regulatory and financial barriers, and discussed the role of regulatory agencies in facilitating research and implementation of these assays. Findings and consensus statements are presented.