Diagnosis of Meningitis Caused by Pathogenic Microorganisms Using Magnetic Resonance Imaging: A Systematic Review

Neuroimaging of the Most Common Meningitis and Encephalitis of Adults: A Narrative Review

Meningitis is the infection of the meninges, which are connective tissue membranes covering the brain, and it most commonly affects the leptomeninges. Clinically, meningitis may present with fever, neck stiffness, altered mental status, headache, vomiting, and neurological deficits. Encephalitis is an infection of the brain, which usually presents with fever, altered mental status, neurological deficits, and seizure. Meningitis and encephalitis are serious conditions which could also coexist, with high morbidity and mortality, thus requiring prompt diagnosis and treatment. Imaging plays an important role in the clinical management of these conditions, especially Magnetic Resonance Imaging. It is indicated to exclude mimics and evaluate the presence of complications. The aim of this review is to depict imaging findings of the most common meningitis and encephalitis.

[Anti-myelin oligodendrocyte glycoprotein antibody-positive unilateral cerebral cortical encephalitis occurring first as general convulsion after meningitis symptoms and second after headache]

The case was a 30-year-old man. He had generalized convulsion after preceding meningitis symptoms and transferred to our emergency department. He was tentatively diagnosed with meningoencephalitis and Todd paralysis based on elevation of cell counts in cerebrospinal fluid and abnormal high signals in the right cerebral cortex on brain FLAIR-MRI, and admitted on the same day. After admission, treatment with antibiotics, dexamethasone, antiviral drug and anticonvulsants was started. Both his clinical symptoms and findings on MRI improved steadily, and then he was discharged on day 19. Subsequently, headache exacerbated again and an additional examination for his serum sample taken on first admission day revealed presence of anti myelin oligodendrocyte glycoprotein (MOG)-antibody, resulting in his diagnosis of anti-MOG antibody unilateral cerebral cortical encephalitis (MOG-UCCE) on day 42. Rehospitalization was planned for introduction of steroid therapy, but generalized convulsion recurred on day 44 and he was hospitalized again. MRI image revealed no FLAIR high signal and cerebrospinal fluid was almost normal, but his headache and mild hemiparesis and numbness on the left side deteriorated again. Therefore, he was treated with intravenous high dose methylprednisolone followed by oral steroids. His clinical symptoms gradually improved, and he was discharged with slight headache on day 71. After discharge, there has been no recurrence under continuation of low dose oral steroids for two years. This case shows the need to measure anti-MOG antibody and introduce steroid therapy in the early phase in a case of suspected MOG-UCCE in a young patient with meningoencephalitis accompanied by generalized convulsion and characteristic abnormal findings on FLAIR-MRI.

Infectious Agents and Stroke: A Systematic Review

Introduction:

A major cause of injury and the second cause of death worldwide is stroke. Among several infectious agents considered as the risk factor of stroke, some pathogens demonstrated stronger robust associations with stroke. Proposing an accurate correlation between infectious microorganisms and stroke provides valuable information for early intervention and control of the infections.

Methods:

In this study, we searched the literature using the Web of Science, PMC/Medline via PubMed, and Scopus databases up to July 2018 without time and language restrictions. After quality assessment, 16 articles were included in the study. The whole data extraction process was independently conducted by two reviewers.

Results:

Based on the results of the studies, viruses, such as Hepatitis C virus (HCV), Hepatitis B virus (HBV), Human Immunodeficiency Virus (HIV), Herpes Simplex Virus Type-1, 2 (HSV-1, 2), Varicella-Zoster Virus (VZV or Chickenpox), and West Nile virus (WNV) seem to be common causes of ischemic stroke. Moreover, the association of other microbial categories, such as Streptococcus mutans (in bacteria), Toxocara spp. and Toxoplasma gondii (in parasites), and Rhizopus sp. (in fungi) with stroke was reported.

Conclusion:

Considering the adverse role of the above-mentioned microorganisms, it is necessary to implement some preventive measures for stroke treatment.

Bacterial meningitis imaging in children

In this review, we provide the data on the modern use of different MRI modalities and computer tomography (CT) as diagnostic and prognostic tools for meningitis of various etiology, first of all, bacterial purulent meningitis. Each of these techniques has its own field of application depending on the stage of the disease and the patients condition (necessity of intensive care procedures, ventilation support). The opinions on the diagnostic value of CT and structural MRI data differ and depend on the etiology and phase of the inflammatory process. In the recent years, the techniques of multiparametric MRI are widely implemented in the practice. Beside structural MRI, they include diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI) and MR spectroscopy (MRS), as well as studies with artificial contrast; there are some reports that these modalities are more effective as a diagnostic tool in meningitis. Thus, the use of multiparametric MRI techniques and CT with contrast is promising and justified for the diagnostics of patients with bacterial purulent meningitis from the viewpoint of enhanced sensitivity.

Intracranial Abnormalities with Diffusion Restriction

Multiple pathologic conditions can cause changes in the random movement of water, which can be detected with diffusion-weighted imaging (DWI). DWI plays a powerful clinical role in detecting restricted diffusion associated with acute brain infarction. Other disorders can also result in restricted diffusion. This article focuses on showing examples of common and uncommon disorders that have restricted diffusion secondary to cytotoxic and/or intramyelinic edema. These disorders include ischemia, infection, noninfectious demyelinating diseases, genetic mutations affecting metabolism, acquired metabolic disorders, toxic or drug exposures, neoplasms and tumorlike lesions, radiation treatment, trauma, and denervation.

Severe Candida glabrata pancolitis and fatal Aspergillus fumigatus pulmonary infection in the setting of bone marrow aplasia after CD19-directed CAR T-cell therapy - a case report

Background

Prolonged myelosuppression following CD19-directed CAR T-cell transfusion represents an important, yet underreported, adverse event. The resulting neutropenia and multifactorial immunosuppression can facilitate severe infectious complications.

Case presentation

We describe the clinical course of a 59-year-old patient with relapsed/refractory DLBCL who received Axicabtagene-Ciloleucel (Axi-cel). The patient developed ASTCT grade I CRS and grade IV ICANS, necessitating admission to the neurological ICU and prolonged application of high-dose corticosteroids and other immunosuppressive agents. Importantly, neutropenia was profound (ANC < 100/μl), G-CSF-refractory, and prolonged, lasting more than 50 days. The patient developed severe septic shock 3 weeks after CAR transfusion while receiving anti-fungal prophylaxis with micafungin. His clinical status stabilized with broad anti-infective treatment and intensive supportive measures. An autologous stem cell backup was employed on day 46 to support hematopoietic recovery. Although the counts of the patient eventually started to recover, he developed an invasive pulmonary aspergillosis, which ultimately lead to respiratory failure and death. Postmortem examination revealed signs of Candida glabrata pancolitis.

Conclusions

This case highlights the increased risk for fatal infectious complications in patients who present with profound and prolonged cytopenia after CAR T-cell therapy. We describe a rare case of C. glabrata pancolitis associated with multifactorial immunosuppression. Although our patient succumbed to a fatal fungal infection, autologous stem cell boost was able to spur hematopoiesis and may represent an important therapeutic strategy for DLBCL patients with CAR T-cell associated bone marrow aplasia who have underwent prior stem cell harvest.