Expanded Dengue Syndrome With Posterior Reversible Encephalopathy Syndrome

Dengue virus infection can present with a wide spectrum of clinical manifestations, ranging from mild febrile illness to severe disease with multiorgan involvement. Neurological complications, though less common, are increasingly recognized in severe dengue, with posterior reversible encephalopathy syndrome (PRES) being a rare association. We report the case of a 16-year-old male presenting with high-grade fever, altered sensorium, and in-hospital seizures in the setting of dengue virus infection. Laboratory evaluation showed dengue NS1 antigen and IgM antibody positivity, thrombocytopenia, and deranged liver and renal function tests. Initial MRI brain was normal, but a repeat MRI following seizure episodes revealed PRES. Supportive management, including adequate hydration, antibiotics, antiepileptic, diuretics, and ventilatory support, led to full neurological recovery. This case illustrates a rare presentation of dengue-associated PRES with multiorgan involvement, highlighting the importance of early recognition and timely supportive management.