# Neuromyelitis Optica Spectrum Disorder Presenting With Organizing Pneumonia: A Case Report and Literature Review

## TL;DR

A case of Neuromyelitis Optica Spectrum Disorder (NMOSD) presented with organizing pneumonia, highlighting the importance of recognizing area postrema syndrome for early diagnosis.

## Contribution

This case report emphasizes area postrema syndrome as a key early symptom of NMOSD in male and older patients with organizing pneumonia.

## Key findings

- NMOSD can present with organizing pneumonia and area postrema syndrome.
- Area postrema syndrome is a critical early sign for diagnosing NMOSD in older male patients.
- Diagnosing NMOSD is challenging when it coexists with organizing pneumonia.

## Abstract

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory disease of the central nervous system (CNS) that can result in severe neurological sequelae. Aquaporin-4, a cause of complement-mediated inflammation in NMOSD, is expressed on alveolar epithelial cells and in the CNS, and organizing pneumonia (OP) is recognized as an extra-CNS symptom in NMOSD. We herein present a case of NMOSD following OP. The patient initially presented with area postrema syndrome, and the coexistence of OP made the diagnosis of NMOSD challenging. A review of previously reported cases of NMOSD with OP suggests that careful attention to area postrema syndrome as an onset symptom is needed for the early diagnosis and treatment of NMOSD in male and older patients with OP.