Spontaneous Subarachnoid Hemorrhage as a Rare Manifestation of Dengue: A Case Report

Dengue fever is a common mosquito-borne viral infection that usually presents with fever, leukopenia, and thrombocytopenia. Neurological involvement is uncommon and typically seen as part of severe or expanded dengue syndrome. Spontaneous subarachnoid hemorrhage (SAH) as a manifestation of dengue is exceedingly rare, with very few cases reported in the literature. We report the case of a 65-year-old previously healthy male who presented with headache, vomiting, and altered sensorium. Neuroimaging revealed extensive subarachnoid hemorrhage with intraventricular extension and hydrocephalus (Fisher Grade 4). Laboratory investigations demonstrated severe thrombocytopenia (15,000/cmm) and positive dengue IgM serology. Digital subtraction angiography excluded aneurysmal or arteriovenous malformations. The patient underwent emergency placement of an external ventricular drain followed by a left ventriculoperitoneal shunt. Supportive management included platelet transfusions, fluid resuscitation, and anticonvulsant therapy. The patient showed marked neurological recovery and was discharged in a stable condition. This case underscores a rare but potentially fatal neurological complication of dengue fever. Clinicians in endemic areas should maintain a high index of suspicion for intracranial bleeding, including SAH, in patients with dengue and severe thrombocytopenia. Early neuroimaging and timely neurosurgical intervention are crucial for favorable outcomes.