Management and predictors of <scp>ICU</scp> admission in <scp>DRESS</scp> : A multicentre retrospective cohort study

Abstract Background Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is a rare but potentially life‐threatening drug‐induced hypersensitivity reaction. Approximately 15% of patients require admission to an intensive care unit (ICU). Objectives To identify factors associated with ICU admission in patients with DRESS in order to improve risk stratification and management. Methods We conducted a multicentre retrospective cohort study including adult patients with probable or definite DRESS (RegiSCAR score ≥4) hospitalized in Greater Paris area hospitals between July 2017 and January 2023. Data were extracted from the Assistance Publique‐Hôpitaux de Paris Health Data Warehouse, covering 39 centres. The primary endpoint was DRESS‐related ICU admission. Secondary endpoints included in‐hospital mortality and therapeutic interventions inside and outside the ICU. Results A total of 207 DRESS cases were included of whom 35 (17%) required ICU admission. Median age was 58 years [IQR 41–72], with a female predominance (62%) and a median Charlson comorbidity score of 3 [1–6]. Anti‐epileptic drugs were the most frequently implicated agents (22%). Hepatic involvement was the most common visceral manifestation (70%), followed by renal (30%), haemodynamic (6.3%), cardiac (5.3%) and pulmonary involvement (1.9%). Disease severity was classified as mild in 40%, moderate in 35% and severe in 25% of cases. Nearly, all patients received corticosteroids, predominantly topical in mild to moderate forms and systemic in severe cases. Overall, in‐hospital mortality was 4.8% ( n = 10), rising to 20% ( n = 7) among ICU patients. In multivariable analysis, hospital‐acquired DRESS (adjusted odds ratio, aOR = 5.21; 95% CI [1.96; 14.1]; p = 0.001) and DRESS severity were independently associated with ICU admission (moderate forms: aOR = 3.74 [1.13; 14.9] and severe forms: aOR = 12.5 [3.79; 51.3], versus minor forms; p &lt; 0.001). Conclusions Nearly one in five hospitalized patients with DRESS required ICU management. Hospital‐acquired DRESS and disease severity were the main determinants of critical care admission, underscoring their prognostic importance.