Clinical Burden of Dengue Fever and On-Admission Atypical Lymphocyte Count as a Prognostic Biomarker – A Case Study

Dengue fever imposes a substantial economic burden on healthcare systems, particularly in low- and middle-income countries. This study aimed to assess the financial impact of dengue fever in a private hospital setting in Sri Lanka and to evaluate the predictive value of on-admission atypical lymphocyte count (ALC) for disease severity, length of hospital stay, and total hospital costs. A retrospective analysis was conducted on 2,185 confirmed dengue patients admitted to Nawaloka Hospital, Colombo, between January 2017 and August 2023. Data on patient demographics, disease severity (per WHO 2009 classification), financial records, and ALC values from the Sysmex XS500i analyzer were extracted. The median total hospital bill was LKR 127,600, with room charges and administrative costs contributing the most. Severe dengue, prolonged hospitalization (>5 days), and insurance coverage were significantly associated with higher hospital bills (p<0.001). Patients with an ALC >0.5×10³/μL on day 3 of fever had significantly longer hospital stays and higher costs compared to those with lower ALC levels. ROC analysis showed that elevated ALC predicted hospital stays >5 days with 94.4% sensitivity and 78.4% specificity, and costs >LKR 132,000 with 95.8% sensitivity and 72.4% specificity. These findings highlight ALC as a practical, early biomarker to stratify dengue patients by risk and optimize resource al-location. The study underscores the need for early clinical decision-making o minimize economic strain on patients, especially those lacking insurance coverage. Further prospective research is recommended to validate ALC as a cost-saving predictive tool in dengue management.