Clinical profiles and factors associated with mortality in adults with yellow fever admitted to an intensive care unit in Minas Gerais, Brazil.

Background: Yellow fever (YF) is a viral hemorrhagic disease caused by an arbovirus from the Flaviviridae family. Data on the clinical profile of severe YF in intensive care units (ICUs) are scarce. This study aimed to evaluate factors associated with YF mortality in patients admitted to a Brazilian ICU during the YF outbreaks of 2017 and 2018.

Methods: This was a longitudinal cohort case series study that included YF patients admitted to the ICU. Demographics, clinical and laboratory data were analyzed. Cox regression identified independent predictors of death risk.

Results: A total of 114 patients were studied. The median age was 48 years, and 92.1% were males. In univariate analysis, jaundice, leukopenia, bradycardia, prothrombin time, expressed as a ratio to the international normalized ratio-(PT-INR), alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin, lactate, arterial pH and bicarbonate, Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score 3 (SAPS 3) severity scores, transfusion of fresh frozen plasma, acute renal failure (Acute Kidney Injury Network stage III (AKIN III)), hemodialysis, cumulative fluid balance at 72 h of ICU, vasopressor use, seizures and grade IV encephalopathy were significantly associated with mortality. In multivariate analysis, factors independently associated with YF mortality were PT-INR, APACHE II, and grade IV hepatic encephalopathy.

Conclusions: In the large outbreak in Brazil, factors independently associated with death risk in YF were: PT-INR, APACHE II, and grade IV hepatic encephalopathy. Early identification of patients with YF mortality risk factors may be very useful. Once these patients with a poor prognosis have been identified, proper management should be promptly implemented.