Adrenal insufficiency in severe West Nile Virus infection

Objective: To explore adrenal function in severe West Nile virus (WNV) infection. Design and setting: Prospective interventional cohort study in a medical ICU of a teaching hospital. Patients: Ten consecutive patients (seven men, mean age 64 ± 12 years, mean SAPS II 26 ± 6) with definite diagnosis of WNV related meningoencephalitis and variable proportion of organ/system failure. All patients had fever (mean body temperature 39 ± 1 °C) and altered mental status (mean Glasgow Coma Score 11 ± 2). Mean SOFA score was 9 ± 2; eight patients had systemic inflammatory response syndrome, five septic shock, and six acute respiratory failure (usually from central origin) requiring mechanical ventilation. Interventions: A short corticotropin test was performed in each patient to assess the adrenal function. Measurements and results: Cortisol response was defined as the difference between baseline and corticotropin-stimulated peak. Absolute adrenal insufficiency was defined by a baseline cortisol level below 15 μg/dl (415 nmol/l). Relative insufficiency was defined by a cortisol response of 9 μg/dl (250 nmol/l) or less. Relative adrenal insufficiency, defined by a corticotropin response below 9 μg/dl, was observed in seven while the remaining three had normal cortisol response; six out of these seven died in the ICU. All patients with normal adrenal function survived. Conclusion: Adrenal insufficiency is frequent in severe WNV infection and carries a poor outcome. In the absence of specific effective treatment, our data provide a rational to investigate a supplemental corticosteroid treatment in a controlled trial.