Aetiologic spectrum of longitudinally extensive spinal cord lesions and clues to their differential diagnosis

The aetiologic diagnosis of longitudinally extensive spinal cord lesions (LESCL) is challenging because its broad differential. Early recognition of diagnostic clues is crucial. With the advent of novel antibody testing, the aetiologic spectrum of LESCL has expanded, yet remains insufficiently characterised in real-world practice. We conducted a single-centre, retrospective cohort study of patients diagnosed with LESCL at a Spanish tertiary hospital between June 2012 and March 2025. Inclusion required suspected myelopathy with MRI involvement of ≥3 consecutive segments, excluding cases where LESCL was not the initial presentation. Clinical, radiological, immunological, and therapeutic data were extracted from medical records. Descriptive analyses with SPSS v20.0 were performed to report the aetiological spectrum, and as an exploratory assessment, to compare potential differences between diagnostic groups. 62 patients of 185 met inclusion criteria. Median age was 49.5 years (19–74), 56% were women. Idiopathic LESCL was most frequent (40%), followed by neuromyelitis optica spectrum disorder (NMOSD, 16%), tumoral (6%), dural arteriovenous fistula (AVF, 6%), infectious (6%), systemic lupus erythematosus (SLE, 5%), multiple sclerosis (MS, 5%), MOG antibody-associated disease (MOGAD, 3%), sarcoidosis (3%), ischaemic (3%), venous infarction (2%), GFAP astrocytopathy (2%), and nutritional deficiency (2%). Distinctive features included conus involvement in MOGAD, optic nerve involvement in NMOSD and MOGAD, perimedullary vascular abnormalities in AVF, and consistent contrast enhancement in tumoral and AVF lesions. Tumoral showed the greatest extension. Prognosis was most favourable in SLE, MS, and MOGAD. Idiopathic LESCL remains the predominant aetiology, followed by NMOSD, but newer entities such as MOGAD and GFAP astrocytopathy broaden the spectrum. Recognition of the specific characteristic is essential to accelerate diagnosis, guide treatment, and improve outcomes.