First Report of Hemorrhagic LETM in NMOSD Highlights Need for Prompt Intervention

Abdorreza Naser Moghadasi, MD, PhD

(Credit: ResearchGate)

Newly published in Clinical Case Reports, researchers have documented a case of hemorrhagic longitudinally extensive transverse myelitis (LETM) in a 51-year-old man with neuromyelitis optica spectrum disorder (NMOSD) for the first time. Although the patient underwent through multiple treatment strategies, the man's condition progressed to irreversible nerve damage, underscoring the importance of early and targeted interventions.¹

In this case, the patient presented with sudden lower-limb paralysis, vertigo, nausea, and a severe headache. Initially diagnosed with myelitis, he partially improved after high-dose corticosteroids and plasmapheresis. However, subsequent COVID-19 infection aggravated his symptoms, leading to a diagnosis of hemorrhagic LETM confirmed via imaging and aquaporin-4 immunoglobulin (AQP4-IgG) seropositivity. Despite intensive treatment, the patient showed no significant improvement in neurological function.

"NMOSD should be considered an important differential diagnosis in cases of hemorrhagic myelitis. However, it is equally crucial to carefully evaluate other possibilities, particularly vascular malformations and tumors," senior author Abdorreza Naser Moghadasi, MD, PhD, an assistant professor of neuroscience at Tehran University of Medical Sciences in Iran, told NeurologyLive^®. "A thorough review of imaging studies is essential in cases that do not respond to treatment. Hyperintensity on T1-weighted imaging can serve as a marker of hemorrhage, but it is easily overlooked. This case is extremely rare, necessitating extensive investigation. Nonetheless, I believe the ultimate diagnosis is accurate."

All told, the patient had no significant medical or family history of autoimmune or neurological disorders. Subsequent cerebrospinal fluid and blood analyses ruled out infections, vitamin deficiencies, and other autoimmune diseases. The patient received initial therapy with 4 g of methylprednisolone and plasmapheresis, achieving partial improvement. Following a COVID-19 infection, he underwent 2 g/kg of IVIG without significant recovery. At a specialized hospital, he was treated with high-dose methylprednisolone (1 g/day for 7 days) and cyclophosphamide (3 g IV for 3 days), but no clinical improvement was observed in his hospital stay of 31 days.

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Authors noted that despite a comprehensive treatment approach, the patient’s condition deteriorated. Furthermore, hemorrhagic LETM was diagnosed more than 2 weeks after initial admission, suggesting that delayed recognition may have contributed to the poor outcome. No additional adverse events were reported from the treatments administered. Researchers noted that the primary limitation was the delayed diagnosis of hemorrhagic LETM, which may have hindered the timely implementation of targeted therapy.

The study authors noted that the current study aligned with results from another case report that involved various disease contexts, where significant recovery was uncommon. Published in the Egyptian Journal of Radiology and Nuclear Medicine, a prior case study described a 15-year-old girl with hemorrhagic LETM and positive MOG antibody who, following prompt and intensive treatment with intravenous pulse methylprednisolone and plasmapheresis, gradually regained her ability to walk.²

Overall, the current case study highlights the potentially aggressive nature of hemorrhagic LETM in NMOSD and the challenges that clinicians could face in its management for their patients. Therefore, early and comprehensive diagnostic workups for demyelinating diseases may be essential to prevent patients from experiencing irreversible neurological damage. Additionally, the interplay between COVID-19 and autoimmune diseases such as NMOSD warrants further investigation to guide clinical management during concurrent infections.

REFERENCES
1. Jahani S, Jamshidi F, Moghadasi AN. Hemorrhagic Longitudinally Extensive Transverse Myelitis (LETM) as a First Presentation of Neuromyelitis Optica Spectrum Disorder (NMOSD): A Case Report and Literature Review. Clin Case Rep. 2025;13(1):e70081. Published 2025 Jan 6. doi:10.1002/ccr3.70081
2. Nerlekar A, Malvadkar S, Patil D, Bhoir B, Shaikh N, Sambare J. A rare presentation of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) as acute hemorrhagic longitudinally extensive transverse myelitis. Egypt J Radiol Nucl Med. 2023;54(1):189.