A Case of Neuromyelitis Optica Spectrum Disorder Aggravated after Varicella Zoster Infection

시각신경척수염은 양측 시신경과 척수를 침범하는 중추신경계의 자가면역성 탈수초 질환이다. 질병 특이적 항체인 AQP-4 항체가 밝혀지면서 기존의 진단 기준이 바뀌었고, 반복성 광범위 횡단 척수염 혹은 반복성 시신경염과 같이 시각신경 척수염의 범주에 속하는 질환에 대한 인식이 생겼다. 시각신경 척수염의 치료는 면역억제제 치료로 스테로이드를 투여하며, 부작용으로 중증 감염이 생길 수 있다. 본 저자들은 면역억제 치료 중에 발생한 수두 감염 이후 시각신경척수염 스펙트럼장애의 악화소견을 보인 1례를 경험하고, 이 증례를 통해 시각신경척수염 스펙트럼장애 치료뿐만 아니라 치료의 부작용을 감시하고 예방하는 것의 중요성을 제시하고자 하였다.

Neuromyelitis optica (NMO) is a rare demyelinating disease of the central nervous system (CNS) that affects the optic nerves and spinal cord. Although aggressive immunosuppressive treatment is mandatory due to the poor prognosis of NMO, there is always a risk of life-threatening infections. A 4-year-old boy was admitted because of headache and weakness of both lower extremities. Brain and spinal magnetic resonance imaging (MRI) demonstrated diffuse ill-defined lesions with T2 hyperintensity in the lower medulla and whole cervical cord. He improved with intravenous immune-globulin (IVIG) and methylprednisolone pulse therapy. However, after 2 years, he developed recurrent vomiting and hyperesthesia on his neck and shoulder. Aquaporin-4 antibody (AQP-4 Ab) was positive in his serum and he was diagnosed with NMO spectrum disorder (NMOSD). After 1 year, he developed a generalized vesicular rash and was treated with acyclovir for chickenpox. However, after 2 weeks, he re-developed left ear vesicles with severe headache and hyperes-thesia on his post scalp and upper shoulder without muscle weakness. His brain and spinal MRI revealed extensively increased T2 hyperintensity lesions down through the upper thoracic cord (T6). He again received IVIG and methylprednisolone pulse therapy, followed by oral prednisolone and azathioprine maintenance. We also treated zoster infection with IV acyclovir for 3weeks and chronic famciclovir pro-phylaxis and neurontin for trigeminal neuralgia. His headache and hyperesthesia showed some improvement, but not complete. Here, we present a case of NMOSD aggravated after varicella zoster infection during chronic steroid maintenance.