MR Features of Varicella-zoster Myelitis in an Immunocompetent Patient.

Background: Varicella-zoster virus (VZV) is a latent virus that can remain in the central nervous system. Reactivation of the virus can cause some neurologic manifestations, and myelitis is one of the rarest of them. In this report, we aimed to present the MRI features of long-segment cervical myelitis after VZV infection, which is rarely reported in the literature.

Case Presentation: A 69-year-old patient, who was diagnosed with varicella-zoster two months ago and treated with valacyclovir, was admitted to our clinic with worsening of his complaints and weakness in the right upper extremity. Neurological examination was normal in the left upper and bilateral lower extremities, but the muscle strength in the right upper extremity was evaluated as 4/5 grade. While rare leukocytes (10 leukocytes/mm³, 50 erythrocytes/mm³, high protein level (46 mg/dl, ref.15- 40 mg/dl)) were seen in the cerebrospinal fluid (CSF) analysis, no microorganisms were seen, and no growth was observed in the culture. VZV antibody-immunoglobulin G (Ab-IgG) was positive in CSF, while polymerase chain reaction [PCR] for VZV was negative. On cervical MRI, lesions showing T2 hyperintensity were observed from the C3-4 level to the C7-T1 level, eccentrically located in the right paramedian spinal cord. On post-contrast images, patchy heterogeneous contrast enhancement was noted in these regions of the spinal cord. When the patient's history, CSF features and MRI examinations were evaluated together, the lesions were consistent with VZV myelitis. The patient was started on valacyclovir treatment, and during the follow-up, the patient's complaints decreased, while no progress was observed in neurologic symptoms.

Conclusion: As a result, we aimed to report the MRI features of this rare complication of varicellazoster and emphasize the necessity of keeping this in mind in the etiology of myelitis, especially in cases with patchy enhancement, to achieve early diagnosis and treatment.