# A Case Report of Longitudinal Extensive Transverse Myelitis: Ruling Out the Known Perpetrators

## TL;DR

A 40-year-old woman with progressive hand weakness was diagnosed with LETM, a rare spinal cord inflammation, and showed significant recovery after steroid treatment.

## Contribution

This case report highlights the importance of early diagnosis and treatment of LETM to prevent severe disability.

## Key findings

- The patient showed 80% resolution of paresthesia and improved motor function after IV methylprednisolone treatment.
- MRI revealed marked improvement with no new enhancement at the two-week follow-up.
- LETM diagnosis was confirmed despite negative autoimmune and infectious workup.

## Abstract

Transverse myelitis (TM) is a rare, heterogeneous syndrome described as acute or subacute inflammation of the spinal cord, and longitudinally extensive transverse myelitis (LETM) is the term used to describe TM that is severe enough to produce T2-weighted high signal intensity on sagittal spinal magnetic resonance imaging (MRI) spanning three or more vertebral segments. We present a case of a 40-year-old African American woman who presented with a 2-day history of progressive bilateral hand weakness. Neurological examination revealed bilateral hand and wrist weakness, more pronounced on the left, with paresthesia from the mid-forearms down, not following a dermatomal pattern. Basic lab work was within normal limits. Autoimmune and infectious workup, including antineutrophil cytoplasmic antibodies (ANCA), thyroid peroxidase (TPO) antibodies, West Nile virus IgG/IgM, and rapid plasma reagin (RPR), was unremarkable. Erythrocyte sedimentation rate (ESR) was elevated at 46. Antinuclear antibodies (ANA) comprehensive plus profile was negative except for positive ribonucleoprotein (RNP) antibodies. Cerebrospinal fluid (CSF) analysis showed no oligoclonal bands. Computed tomography (CT) scan of the head and MRI of the brain were normal. MRI of the cervical and thoracic spine revealed patchy, irregular increased signal from C4-C7. The patient was diagnosed with LETM. She was started on IV methylprednisolone for three days, followed by tapering doses of oral prednisolone, and reported 80% resolution of paresthesia and improved upper limb motor function. At the two-week neurology follow-up, the patient reported near-complete recovery. Repeat cervical spine MRI showed marked improvement with no new enhancement. Despite being uncommon, LETM has devastating clinical outcomes, and many patients suffer from severe disability if treatment is delayed. In order to achieve maximally beneficial outcomes and, in some situations, initiation of the right treatment to avoid further bouts of central nervous system (CNS) inflammation, early identification and the etiology of LETM are crucial.