Myelopathy in West Nile virus encephalitis: Report of a case and review of literature

A Case Report of NMO Transverse Myelitis

BACKGROUND

Transverse myelitis is considered one of the cardinal features of neuromyelitis optica spectrum disorder (NMOSD), an immune-mediated inflammatory condition of the CNS characterized by severe, immune-mediated demyelination and axonal damage predominantly targeting optic nerves and spinal cord. We describe a case in which a diagnosis of NMOSD was established, associated with West Nile Virus (WNV) infection.

CASE PRESENTATION

A healthy 18-year-old female presented with intractable hiccups and rapidly progressing paraparesis. MRI demonstrated T2 edema extending from the medulla to the conus, consistent with longitudinally extensive transverse myelitis. Serum and CSF Aquaporin-4 IgG (AQP4) were both positive with high titers. In conjunction with antiviral therapy, immunomodulatory treatment was initiated using pulse methylprednisolone, plasmapheresis and Rituximab. A month and a half after admission, the patient was fully ambulatory with no residual symptoms. On her rheumatology follow-up visit, West Nile Virus-specific IgM in CSF was found to be positive from the patient's initial presentation.

CONCLUSION

We propose that West Nile Virus may have been the autoimmune trigger to the patient's development of NMOSD, highlighting the importance of evaluating viral triggers in autoimmune diseases.

Bilateral Upper Extremity Tremors in West Nile Encephalitis

West Nile encephalitis is a rare complication of infection from the West Nile virus (WNv). Viral encephalitis can mimic manifestations of other neurologic diseases. The purpose of this article is to report a case of a 60-year-old female who developed bilateral upper extremity tremors with West Nile encephalitis. She presented to a hospital in Southern Louisiana with persistent high fevers and new onset confusion. She soon developed tremors which persisted throughout her hospitalization. Computerized tomography (CT) of the head revealed no abnormalities. Cerebral spinal fluid (CSF) was remarkable for WNv IgM, and supportive care was pursued. After nearly three weeks, she was transferred to a skilled nursing facility for further care. The presentation of movement disorder with confusion usually raises concern for injury to the brain or spinal cord or other neurologic illnesses. Despite the presentation of movement disorders or other neurologic manifestations, viral etiologies should remain high on the differential when the patient has additional symptoms, such as fever and elevated white blood cell (WBC) count, to limit inappropriate diagnostic testing and treatment.

Acute Polyradiculomyelitis With Spinal Cord Gray Matter Lesions: A Report of Two Cases

Objective: Inflammatory polyradiculomyelitis belongs to a rare group of immune-mediated diseases affecting both the central and peripheral nervous system. We aimed to describe an unusual presentation of acute polyradiculomyelitis with marked spinal cord lesions restricted to the gray matter.

Methods: Thorough examination of two case reports including clinical, MRI, serologic, electrophysiologic and CSF examinations as well as short-term follow-up.

Results: We present two adult patients with acute polyradiculomyelitis and unusual spinal cord lesions restricted to the gray matter on MRI. The clinical presentation, serologic, electrophysiologic and CSF features of the two patients varied, whereas both patients demonstrated severe, asymmetrical, predominantly distal, motor deficits of the lower extremities as well as bladder and bowel dysfunction. Both patients only partially responded to anti-inflammatory treatment. Severe motor impairment and bladder dysfunction persisted even months after symptom onset.

Conclusions: To our best of knowledge, these are the first reports of acute polyradiculomyelitis with distinct involvement of the lower thoracic spinal cord gray matter. Currently, it remains unclear whether gray matter lesions reflect a separate pathophysiologic mechanism or an exceedingly rare presentation of spinal cord involvement in acute polyradiculomyelitis.

Global emergence of West Nile virus: Threat & preparedness in special perspective to India

West Nile virus (WNV) is a mosquito-borne single-stranded RNA neurotropic virus within the family Flaviviridae. The virus was first reported in the West Nile province of Uganda in 1937. Since then, sporadic cases have been reported until the last two decades when it has emerged as a threat to public health. The emergence of WNV with more severity in recent times is intriguing. Considering this phenomenon, the WNV-affected areas of the world were distinguished as old versus new in a depicted world map. The present review showcases the historical and epidemiological perspectives of the virus, genetic diversity of prevailing lineages and clinical spectrum associated with its infection. Emergence of the virus has been discussed in special context to India because of co-circulation of different WNV lineages/strains along with other flaviviruses. Recent laboratory diagnostics, vaccine development and clinical management associated with WNV infection have also been discussed. Further, the research gaps, especially in context to India have been highlighted that may have a pivotal role in combating the spread of WNV.

Longitudinally extensive transverse myelitis in a patient infected with West Nile virus

Until now, longitudinally extensive transverse myelitis (LETM) was reported in association with various viral infections. We describe the case in which a diagnosis of LETM was established as a clinical manifestation of West Nile virus (WNV) infection. We report a 39-year old man with WNV infection and LETM. In neurological examination, there was a left periscapular hypotrophy, moderate weakness of left arm, decreased left brachioradialis reflex, tandem instability and gait ataxia. Cervical spine MRI showed enhancing intramedullary lesion extending from C3-C7 level. According to the neurological, EMG and MRI findings, a diagnosis of LETM, with affection of anterior horn cells of the cervical spinal cord, induced by WNV infection was established. The patient was treated with antibiotics, acyclovir and high dose-steroids, methylprednisolone (MP) 1 g/daily in intravenous infusion, for 5 consecutive days, followed by tapering doses of prednisone during the next four months. Six weeks after onset of symptoms, previously described lesion on cervical spine MRI resolved, and the patient gradually clinically improved.