Atypical presentation and severity of Dengue fever in patients with CKD

BACKGROUND AND HYPOTHESIS: Dengue fever and chronic kidney disease (CKD) are growing health concerns. However, the features and indicators of severe dengue (SD) in CKD patients remain poorly understood. This study aimed to describe dengue in CKD patients, test the relationship between CKD and SD and identify indicators of SD during the 2019 dengue epidemic in La Réunion Island, a region with high prevalence of metabolic diseases and dengue transmission. METHODS: A retrospective cohort study was conducted on patients aged ≥ 15 years with dengue who presented to the University Hospital of La Réunion between January and June 2019. CKD was defined according to KDIGO criteria. Clinical, biological, and outcome data were extracted from the EPIDENGUE database. We used nonconditional logistic regression models to identify dengue-specific indicators in CKD patients and indicators of SD (WHO-2009 definition) and conditional models to assess the relationship between CKD and SD. RESULTS: Of 1 498 confirmed dengue cases, 105 (7%) had CKD. CKD patients were older (median age 77 vs. 51 years) with more comorbidities, especially diabetes and hypertension. They displayed a distinct dengue phenotype, with fewer classic symptoms (myalgia, rash) but more dyspnea, encephalopathy, anemia, inflammation, and neutrophil-to-platelet ratios. CKD patients were more likely to develop SD (46% vs. 18%, p < 0.001; conditional OR 1.93; 95%CI 1.21-3.06) and mortality (6.7% vs. 1.6%). Severe renal involvement was the main driver of severity. WHO warning signs were poor indicators of SD in CKD patients. In multivariate analysis, insulin-treated diabetes, afebrile presentation, and early cardiorespiratory involvement indicated SD. CONCLUSION: CKD alters the presentation and worsens the prognosis of dengue independently of confounders. Classical warning signs are insufficient in predicting SD among CKD patients. Diabetes, afebrile presentation, and early cardiorespiratory symptoms require closer monitoring and early hospitalization. CKD patients are a high-risk group needing tailored diagnostic and preventive strategies.