Distinguishing cytomegalovirus meningoencephalitis from other viral central nervous system infections

Clinical presentation of cytomegalovirus meningoencephalitis: a retrospective study of 12 adult patients with a variety of immunocompromised conditions

BACKGROUND

Human Cytomegalovirus (HCMV) is a crucial pathogen in immunocompromised individuals, causing infections such as pneumonitis, colitis, and retinitis. However, research on HCMV infections of the central nervous system (CNS) is limited.

OBJECTIVE

This retrospective cohort study aimed to investigate the clinical manifestations, underlying conditions, laboratory findings, imaging findings, treatments, and outcomes of adult patients diagnosed with HCMV meningitis or encephalitis at a single medical center in East Asia over a 6-year period.

METHODS

The study included patients who had positive results in quantitative polymerase chain reaction (PCR) tests of their cerebrospinal fluid (CSF) for HCMV at any time between January 2017 and December 2022. Clinical characteristics, laboratory findings, imaging findings, treatment approaches, and outcomes were reviewed and analyzed from electronic medical records.

RESULTS

The cohort comprised 12 patients with a median age of 61 years (range, 43-84 years). Stupor and generalized seizures were the most common neurological presentations. Brain imaging findings in half of the patients revealed nonspecific abnormalities, such as atrophy. CSF protein levels were elevated, with a median of 74.5 mg/dL. CSF pleocytosis was observed in three patients (25%) and was predominantly lymphocytic. The in-hospital mortality rate was 75% (9 out of 12 patients).

CONCLUSIONS

Although rare, HCMV CNS infections are associated with a high mortality rate. CSF pleocytosis is uncommon in such cases, potentially contributing to clinical misdiagnosis or underestimation. HCMV meningoencephalitis should be considered in immunocompromised patients who present with unexplained seizures or altered consciousness.

Successfully salvaging a HIV-positive patient with mixed CIDP and meningoencephalitis: a case report

We describe an acquired immunodeficiency syndrome (AIDS) patient who first exhibited chronic inflammatory demyelinating polyneuropathy (CIDP) and subsequently developed meningoencephalitis due to ganciclovir (GCV)-resistant cytomegalovirus (CMV) infection. The patient first presented with peripheral nervous system (PNS) symptoms, followed by central nervous system (CNS) symptoms. Based on auxiliary examinations, including cerebrospinal fluid (CSF) tests, electromyography (EMG), brain magnetic resonance imaging (MRI) and GCV drug resistance tests, the patient was diagnosed with CIDP and meningoencephalitis due to CSF GCV-resistant CMV. After the combined application of intravenous immunoglobulin treatment, corticosteroid treatment, antiretroviral therapy (ART), and adjusted anti-CMV treatment, the patient achieved persistent relief. This case underscores the importance of considering CMV as a common etiology of neurological disorders in AIDS patients. It also highlights the necessity of prompt drug resistance testing when anti-CMV therapy yields suboptimal responses.

Infectious Neuropathies

This review explores diverse infectious etiologies of peripheral nervous system (PNS) dysfunction, spanning sensory and motor neurons, nerves, and associated structures. Progress in viral and bacterial infections reveals multifaceted mechanisms underlying neuropathies, including viral neurotoxicity and immune-mediated responses. Latest diagnostic advances facilitate early PNS complication detection, with ongoing research offering promising treatment avenues. Emerging pathogens like severe acute respiratory syndrome coronavirus 2, Zika virus, and EV-D68 highlight the evolving infectious neuropathy paradigm. Recognizing characteristic patterns and integrating clinical factors are pivotal for precise diagnosis and tailored intervention. Challenges persist in assessment and management due to varied pathogenic mechanisms. Advancements in understanding pathogenesis have improved targeted therapies, yet gaps remain in effective treatments. Ongoing research is crucial for optimizing approaches and improving patient outcomes.

Varicella-zoster virus meningitis with hypoglycorrhachia, presenting with painless occipital herpes zoster mimicking atopic dermatitis

Varicella-zoster virus (VZV) is a known cause of meningoencephalitis, typically in immunocompromised inpatients. We report a case of meningitis caused by VZV in an immunocompetent man in his 20s. Diagnosis was delayed due to the atypical presentation of painless occipital zoster mimicking atopic dermatitis, and the presence of hypoglycorrhachia in his cerebrospinal fluid. The clinical diagnosis of VZV meningitis poses significant diagnostic challenges, and nucleic acid tests for VZV detection are recommended for patients with severe cases who require empiric acyclovir treatment.

A Multiplex Polymerase Chain Reaction Assay for the Detection of Herpes Simplex Virus, Cytomegalovirus, and Varicella-Zoster Virus in Cerebrospinal Fluid

Viral meningitis poses a significant clinical challenge due to its rapid onset and potential progression to life-threatening encephalitis. Early detection of treatable viral pathogens such as Herpes simplex virus (HSV), Cytomegalovirus (CMV), and Varicella-zoster virus (VZV) is essential for initiating appropriate therapies. However, multiplex PCRs for the rapid and simultaneous detection of these pathogens are scarce due to the complex PCR design and the elaborate validation process using cerebrospinal fluid samples. In this study, we established and validated a novel multiplex PCR assay for detecting HSV, CMV, and VZV in cerebrospinal fluid samples and implemented the assay on a fully automated platform.

What intensivists need to know about cytomegalovirus infection in immunocompromised ICU patients

PURPOSE

Advances in therapeutic care are leading to an increase in the number of patients living with overt immunosuppression. These patients are at risk of cytomegalovirus (CMV) infection and disease that can lead to or develop during ICU admission. This manuscript aims to describe the clinical presentation, risk factors, and management of CMV infection and disease in this patient population.

METHODS

We conducted a literature search in PubMed up to April 2024, focusing on CMV infection and disease in patients with overt immunosuppression (hematopoietic stem cell and solid organ transplantation, solid or hematologic malignancies, HIV infection, immunosuppressive drugs, including corticosteroids, and primary immunodeficiencies) admitted to the intensive care unit (ICU). As there is limited ICU-specific data on CMV in immunosuppressed patients, many of the findings were extrapolated from the general literature.

RESULTS

CMV infection and disease in immunocompromised critically ill patients is associated with increased mortality and presents significant management challenges. Clinical manifestations are diverse, shaped by the underlying immune deficiency and primary disease. Pneumonia and encephalitis are among the most severe CMV end-organ diseases. CMV infection may also increase the risk of secondary infections and induce life-threatening conditions, such as thrombotic microangiopathy. Importantly, CMV reactivation is not synonymous with CMV disease, and qPCR testing of body fluids cannot reliably differentiate between viral shedding and tissue-invasive infection, which requires histopathological confirmation. Ganciclovir is commonly the first-line anti-viral, though maribavir shows potential for patients unresponsive to other antivirals. Identifying patients who require prophylactic or preemptive antiviral therapy is essential.

CONCLUSIONS

CMV infection and disease in critically ill immunocompromised patients pose a unique challenge for intensivists. The broad spectrum of clinical presentations and the difficulty in distinguishing CMV-related symptoms from other causes require a high level of clinical suspicion. Accurate interpretation of nucleic acid load levels and careful evaluation of CMV's pathogenic role when it is found are critical. Further studies focusing specifically on CMV infection and disease in critically ill immunocompromised patients are needed to optimize management strategies.

West Nile virus encephalitis: Clinical characteristics and a comparison to other infectious encephalitides

PURPOSE

To compare functional outcomes and help differentiate between important causative agents of acute infectious encephalitis in adults, focusing on West Nile virus encephalitis (WNVE).

METHODS

The electronic database of Tel Aviv Medical Center was screened for patients admitted during 2010-2020 with acute encephalitis. Additionally, patient laboratory results during the same period were screened for CSF samples positive for common pathogens causing encephalitis. The main patient groups were compared in terms of clinical characteristics and functional outcomes.

RESULTS

One hundred and five infectious encephalitis patients were identified. WNVE patients (n = 31) and VZV encephalitis (VZVE) patients (n = 31) were older than HSV1 encephalitis (HSV1E) patients (n = 15) (median ages 73, 76, 51, respectively). WNVE patients had a more prominent inflammatory profile. CSF characteristics significantly differed between groups, with an extreme mononuclear white blood cell predominance in VZVE patients (median 98%). Functional outcomes at discharge were significantly worse in WNVE patients (median modified Rankin Scale score 4 at hospital discharge, 2.5 at last follow-up) when compared with HSV1E patients (2.5, 1, respectively) and VZVE patients (1.5, 1, respectively).

CONCLUSION

In odds with previous reports, WNVE and VZVE in this study were far more prevalent than HSV1E. Differences in clinical characteristics could prove clinically useful early in encephalitis, including an association of WNVE with a relatively prominent inflammatory profile (somewhat resembling a bacterial infection) and an extreme mononuclear white blood cell predominance in VZVE. The detrimental outcome of WNVE emphasizes the need to advance research on WNV infection.

[Cytomegalovirus Encephalitis Presenting With Palpitations as the Initial Symptom After Hematopoietic Stem Cell Transplantation to Treat Acute Lymphoblastic Leukemia in a Child: A Case Report]

Hematopoietic stem cell transplantation (HSCT) patients may develop cytomegalovirus encephalitis, a rare but life-threatening complication with a mortality rate exceeding 90%. Cytomegalovirus encephalitis is rare and does not have specific clinical manifestations, which makes clinical diagnosis more difficult. This article reports a pediatric case of acute lymphoblastic leukemia (ALL) with early onset (81 d after transplantation) cytomegalovirus encephalitis after HSCT, with palpitations presenting as the initial symptom. The patient exhibited rapid clinical progression and the treatment was ineffective. This case report can help clinicians gain further understanding of the high-risk factors and clinical features of central nervous system complications following HSCT. When encountering unexplained tachycardia, clinicians should still be vigilant for the possibility of intracranial infection even in the absence of typical neurological manifestations associated with encephalitis. Early recognition and management may help improve the outcomes of such patients.

The ATP-Binding Cassette Transporter-Mediated Efflux Transport of Ganciclovir at the Blood-Brain Barrier

BACKGROUND AND OBJECTIVE

Recent studies have highlighted the key role of the ATP-binding cassette (ABC) transporters, including the P-glycoprotein (P-gp), the breast cancer resistance protein (BCRP), and the multi-drug resistance protein 4 (MRP4) in limiting the brain distribution of several antiviral agents. In this study, we investigated whether the inhibition of these transporters increases the permeability of the blood-brain barrier (BBB) to ganciclovir.

METHODS

A microdialysis and high-performance liquid chromatographic method was developed to monitor the concentrations of unbound ganciclovir in the brain interstitial fluid and plasma, with and without the administration of ABC transporter inhibitors. Pharmacokinetic parameters, including the area under the plasma concentration-time curve from time 0 to time of the last measurable analyte concentration (AUC0-t,plasma), the area under the brain interstitial fluid concentration-time curve from time 0 to time of the last measurable analyte concentration (AUC0-t,brain), and the unbound brain-to-plasma concentration ratio (Kp,uu,brain) were calculated.

RESULTS

The mean AUC0-t,plasma, AUC0-t,brain, and Kp,uu,brain in rats who received ganciclovir (30 mg/kg, intraperitoneal) alone were 1090 min·µg/mL, 150 min·µg/mL, and 14%, respectively. After the administration of tariquidar (inhibitor of P-gp), Ko143 (inhibitor of BCRP), or MK-571 (inhibitor of MRP4), the Kp,uu,brain of ganciclovir increased to 31 ± 2.1%, 26 ± 1.3%, and 32 ± 2.0%, respectively.

CONCLUSIONS

The findings of this study suggest that ABC transporters P-gp, BCRP, and MRP4 mediate the efflux of ganciclovir at the BBB and that the inhibition of these transporters facilitates the penetration of the BBB by ganciclovir.

Varicella-zoster virus-related neurological complications: From infection to immunomodulatory therapies

The Varicella-zoster virus (VZV), classified as a neurotropic member of the Herpesviridae family, exhibits a characteristic pathogenicity, predominantly inducing varicella, commonly known as chickenpox, during the initial infectious phase, and triggering the reactivation of herpes zoster, more commonly recognized as shingles, following its emergence from a latent state. The pathogenesis of VZV-associated neuroinflammation involves a complex interplay between viral replication within sensory ganglia and immune-mediated responses that contribute to tissue damage and dysfunction. Upon primary infection, VZV gains access to sensory ganglia, establishing latent infection within neurons. During reactivation, the virus can spread along sensory nerves, triggering a cascade of inflammatory mediators, chemokines, and immune cell infiltration in the affected neural tissues. The role of both adaptive and innate immune reactions, including the contributions of T and B cells, macrophages, and dendritic cells, in orchestrating the immune-mediated damage in the central nervous system is elucidated. Furthermore, the aberrant activation of the natural defence mechanism, characterised by the dysregulated production of immunomodulatory proteins and chemokines, has been implicated in the pathogenesis of VZV-induced neurological disorders, such as encephalitis, myelitis, and vasculopathy. The intricate balance between protective and detrimental immune responses in the context of VZV infection emphasises the necessity for an exhaustive comprehension of the immunopathogenic mechanisms propelling neuroinflammatory processes. Despite the availability of vaccines and antiviral therapies, VZV-related neurological complications remain a significant concern, particularly in immunocompromised individuals and the elderly. Elucidating these mechanisms might facilitate the emergence of innovative immunomodulatory strategies and targeted therapies aimed at mitigating VZV-induced neuroinflammatory damage and improving clinical outcomes. This comprehensive understanding enhances our grasp of viral pathogenesis and holds promise for pioneering therapeutic strategies designed to mitigate the neurological ramifications of VZV infections.

Understanding the Neurotrophic Virus Mechanisms and Their Potential Effect on Systemic Lupus Erythematosus Development

Central nervous system (CNS) pathologies are a public health concern, with viral infections one of their principal causes. These viruses are known as neurotropic pathogens, characterized by their ability to infiltrate the CNS and thus interact with various cell populations, inducing several diseases. The immune response elicited by neurotropic viruses in the CNS is commanded mainly by microglia, which, together with other local cells, can secrete inflammatory cytokines to fight the infection. The most relevant neurotropic viruses are adenovirus (AdV), cytomegalovirus (CMV), enterovirus (EV), Epstein-Barr Virus (EBV), herpes simplex virus type 1 (HSV-1), and herpes simplex virus type 2 (HSV-2), lymphocytic choriomeningitis virus (LCMV), and the newly discovered SARS-CoV-2. Several studies have associated a viral infection with systemic lupus erythematosus (SLE) and neuropsychiatric lupus (NPSLE) manifestations. This article will review the knowledge about viral infections, CNS pathologies, and the immune response against them. Also, it allows us to understand the relevance of the different viral proteins in developing neuronal pathologies, SLE and NPSLE.

Viral meningitis and encephalitis: an update

PURPOSE OF REVIEW

The most common infectious etiologies of meningitis and encephalitis are viruses. In this review, we will discuss current epidemiology, prevention, diagnosis, and treatment of the most common causes of viral meningitis and encephalitis worldwide.

RECENT FINDINGS

Viral meningitis and encephalitis are increasingly diagnosed as molecular diagnostic techniques and serologies have become more readily available worldwide but recent progress in novel antiviral therapies remains limited. Emerging and re-emerging viruses that have caused endemic or worldwide outbreaks or epidemics are arboviruses (e.g., West Nile virus, Japanese encephalitis, Tick borne encephalitis, Dengue, Zika, Toscana), enteroviruses (e.g., Enterovirus 71, Enterovirus D68), Parechoviruses, respiratory viruses [e.g., severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza, metapneumoviruses, measles, mumps], and herpes viruses [e.g., herpes simplex virus (HSV) type 1 (HSV-1), HSV-2, human herpes (HV) 6, varicella zoster virus (VZV)]. Future efforts should concentrate in increasing availability for those viruses with effective vaccination [e.g., Japanese encephalitis, Tick borne encephalitis, varicella zoster viruses, SARS-CoV-2, influenza], prompt initiation of those with encephalitis with treatable viruses (e.g., HSV-1, VZV), increasing the diagnostic yield by using novel techniques such as metagenomic sequencing and avoiding unnecessary antibiotics in those with viral meningitis or encephalitis.

SUMMARY

We review the current epidemiology, clinical presentation, diagnosis, and treatment of the common causative agents of viral meningitis and encephalitis worldwide.

Severe, Progressive Meningoencephalitis in a Patient with Coexisting SARS-CoV-2 and Cytomegalovirus Infection: A Case Report

: SARS-CoV-2, the pathogen responsible for COVID-19, has infected hundreds of millions since its emergence in late December 2019. Recently, concern has been raised due to the increased prevalence of co-infections with opportunistic pathogens among these patients. Though not common, co-infections may be associated with adverse outcomes and increased risk of morbidity and mortality among patients suffering from COVID-19. Cytomegalovirus (CMV) infection is a serious problem among immunocompromised and critically ill patients. So far, few cases of co-infection with COVID-19 and CMV have been reported. Here, we report the co-infection with COVID-19 and CMV in a young woman presenting with sudden, progressive fever, delusion, agitation, bizarre behavior, seizure, and loss of consciousness leading to death despite receiving appropriate anti-viral treatment. To the best of our knowledge, this is the first case of coexisting SARS-CoV-2 and CMV infection presenting with severe, progressive meningoencephalitis in the era of COVID-19.

Herpesvirus-Associated Encephalitis: an Update

Purpose of Review

Recent Findings

Summary

Severe cytomegalovirus encephalitis in an immunocompetent healthy young woman: A case report

Cytomegalovirus (CMV) causes a mild illness in immunocompetent patients. Conversely, it can be life-threatening in immunocompromised or critically ill patients. We present a 48-year-old immunocompetent woman presenting primary severe CMV encephalitis. She presented with a headache, fever, and drowsiness. She did not respond to empirical treatment. Her level of consciousness deteriorated, she was put on mechanical ventilation on day two. Bacterial culture, herpes simplex virus, and tuberculosis were negative in cerebrospinal fluid (CSF). After three weeks, the patient was transferred to our center due to financial matters. Brain magnetic resonance imaging (MRI) showed diffuse hydrocephalus, periventricular T2 hyperintensity, patchy basal ganglia, and diffuse leptomeningeal enhancement. CMV polymerase chain reaction (PCR) was positive in cerebrospinal fluid (CSF) specimen. Ganciclovir (5 mg/kg/IV q12h) was initiated. Subsequently, a brain shunt was inserted. Her level of consciousness raised, she was weaned from the ventilator. She was discharged after 52 days in a bedridden state, quadriplegic, and only able to speak words with a minor swallowing problem. She remained in the same condition for one year. She was expired one year later due to aspiration pneumonia after four weeks of hospitalization. Early diagnosis and treatment of severe CMV encephalitis are crucial to prevent neurological sequelae.