Nationwide Analysis of In-Hospital Mortality in Patients with Encephalitis-Related Diagnoses in Ecuador

Background/Objectives: Encephalitis and related acute encephalopathic syndromes represent severe neurological conditions with diverse etiologies and variable clinical outcomes. This study aimed to analyze nationwide hospitalization patterns for encephalitis-related diagnoses in Ecuador between 2018 and 2024. Methods: We used data from the Ecuadorian National Institute of Statistics and Census to estimate age-adjusted hospitalization and mortality rates according to ICD-10 codes. Binary and multinomial logistic regression models were employed to identify sociodemographic factors and diagnostic categories of encephalitis associated with hospitalization and in-hospital mortality. Results: A total of 1560 hospitalizations related to encephalitis-spectrum diagnoses were recorded, with an overall age-adjusted rate of 0.127 per 100,000 inhabitants and 6.0% in-hospital mortality. Unspecified encephalitis and encephalomyelitis were the most common diagnostic categories. Adolescents (10–19 years) were more frequently diagnosed with acute disseminated and bacterial meningoencephalitis, while patients aged ≥70 had higher odds of “other” encephalitis subtypes and the highest mortality risk (aOR = 0.265; 95% CI: 0.116–0.608). Indigenous individuals were more likely to be diagnosed with acute disseminated encephalitis, and Black individuals showed a higher risk for myelopathy associated with human T-cell lymphotropic virus type 1-associated myelopathy. Conclusions: Age and ethnicity significantly influence hospitalization due to encephalitis-related diagnoses in Ecuador. These findings provide epidemiological rates for a lower-middle–income country where the lack of precise diagnosis, age, and ethnicity contribute to the vulnerability of encephalitis.