Fatal central nervous system co-infection with SARS-CoV-2 and tuberculosis in a healthy child.

Background: Central and peripheral nervous system symptoms and complications are being increasingly recognized among individuals with pandemic SARS-CoV-2 infections, but actual detection of the virus or its RNA in the central nervous system has rarely been sought or demonstrated. Severe or fatal illnesses are attributed to SARS-CoV-2, generally without attempting to evaluate for alternative causes or co-pathogens.

Case Presentation: A five-year-old girl with fever and headache was diagnosed with acute SARS-CoV-2-associated meningoencephalitis based on the detection of its RNA on a nasopharyngeal swab, cerebrospinal fluid analysis, and magnetic resonance imaging findings.

Differentiation between intra-axial metastatic tumor progression and radiation injury following fractionated radiation therapy or stereotactic radiosurgery using MR spectroscopy, perfusion MR imaging or volume progression modeling.

Objective: To determine the accuracy of magnetic resonance spectroscopy (MRS), perfusion MR imaging (MRP), or volume modeling in distinguishing tumor progression from radiation injury following radiotherapy for brain metastasis.

Methods: Twenty-six patients with 33 intra-axial metastatic lesions who underwent MRS (n=41) with or without MRP (n=32) after cranial irradiation were retrospectively studied. The final diagnosis was based on histopathology (n=4) or magnetic resonance imaging (MRI) follow-up with clinical correlation (n=29).

Brain lesions with elevated lactic acid peaks on magnetic resonance spectroscopy.

Magnetic resonance (MR) spectroscopy is a noninvasive imaging tool that provides information on various metabolite concentrations within brain lesions. The biochemical information obtained with MR spectroscopy, along with the morphologic appearance of a lesion on MR imaging, allows for better characterization and improved diagnostic ability. Lactic acid is an end product of anaerobic metabolism.

West nile virus encephalitis involving the substantia nigra: neuroimaging and pathologic findings with literature review.

West Nile virus has become a medically important arbovirus in the continental United States with its debut in 1999 in the New York City area. We present neuroimaging features and pathologic findings in 2 patients who were severely affected out of the more that 100 documented cases at our institution. Both patients showed striking involvement of the substantia nigra, a finding not previously reported for West Nile virus.