Introduction: To describe our experience in the etiology, evolution, and sequelae of non-traumatic acute myelophaty (NTAM).

Material and methods: A retrospective, observational study of medical records of 76 patients who presented with NTAM was conducted. NTAM was defined as spinal cord involvement with motor and/or sensory deficits and/or sphincter dysfunction that reaches its nadir over the course of 3 weeks.

Results: Patients were classified into 4 groups according to etiology: A (n=11) tumor compression, being PNET the most-frequent tumor. B (n=9) vascular: 3 spinal AVM; 6 ischemic (4 procedure-related, 2 idiopathic). C (n=10) infectious: 2 mycobacterium; 1 bacterium; 1 CMV; 1 arbovirus; 4 enterovirus; 1 histoplasmosis. D (n=46) inflammatory/demyelinating: 31 ADEM, NMO, MS; 12 idiopathic transverse myelitis; 3 lupus. The most frequent clinical presentation in all groups was gait abnormality and sphincter dysfunction. A rapid symptom onset (within hours) was characteristic of group B (p=0.00).Visual and sensory impairment and relapses were exclusively seen in group D. Sequelae were the most frequent in group A  and the least frequent in group D (p=0.025). The most-common sequela in all groups was paraparesis. CSF parameters of inflammation and a contrast-enhancing spinal cord MRI were only found in group C and D.

Conclusions: In the face of an NTAM patient, abroad range of possible causes should be considered. These causes should guide the request of complementary studies and treatment strategy.An inflammatory/demyelinating etiology was most frequently observed in our series and was associated with better outcome.