Non-Immune Causes of Longitudinally Extensive TransverseMyelitis: Lessons Learnt from A Tertiary Care Cohort
Authors
Varsha Patil, Dr. Sunetra D Phulsunge, Dr. Satish V Khadilkar, Dr. Samantha Kumar, Dr. Sunila T Jaggi, Dr. Jimmy Lalkaka, Dr. Vibhor Pardasani, Dr. B S SinghalFiles
Key Information
Journal
Published in Vol. 68 No. 1 (2026) of Bombay Hospital Journal.
Bombay Hospital Journal (BHJ) is a peer-reviewed quarterly published Print and Online journal. It is an official Journal of Bombay Hospital institute of medical sciences. The aim of BHJ is to improve medical care by publishing sound scientific articles (both research and practice papers) and focusing on topics that are of great importance to its readership.
Editor-in-Chief- Dr Satish Vasant Khadilkar
About the JournalAbstract
Background: Longitudinally extensive transverse myelitis (LETM) is often presumed to be immune‑mediated. However, a
substantial proportion of LETM arises from non‑immune causes that closely mimic inflammatory myelitis, leading to diagnostic
delays and inappropriate immunotherapy.
Objectives: The aim of the present study was to describe the clinical and radiological characteristics of LETM due to non-immune
causes and highlight red flag features that differentiate these conditions from immune‑mediated LETM.
Methods: We retrospectively reviewed LETM cases who presented to our tertiary care centre over a period of 6 years (2019–2025)
and analysed cases due to non-immune causes.
Results: Out of a total 43 LETM cases, 27 cases with a non-immune cause were included in the present study. These included
various etiological categories: infectious (n=11), vascular (n=5), nutritional (n=4), neoplastic/paraneoplastic (n=4) and compressive
(n=3). The diagnostic delay in cases with vascular etiologies was more compared to other causes. 55% (5/27) of cases received
immunotherapy before final diagnosis was established. Clinical and radiological diagnostic clues differentiating various etiologies
were strikingly different compared to the immune mediated group.
Conclusion: Non-immune causes constitute a significant proportion of LETM in endemic regions. Recognizing red flag features
is essential to avoid misclassification as immune-mediated LETM. Early identification of reversible etiologies such as vitamin B12
deficiency and spinal dural arterio-venous fistula significantly alters outcomes. Bottom of Form
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