Madhusanaka, R.B. D.Pathirage, L.P.M.M. K.Perera, S.Kularatne, S.A.M.Abeykoon, W.D.S.E.2025-11-032025-11-032024-08-29Proceedings of the Peradeniya University International Research Sessions (iPURSE) – 2024, University of Peradeniya, P 561391-4111https://ir.lib.pdn.ac.lk/handle/20.500.14444/5924Dengue is an arboviral infection endemic to the tropical countries. Neurological sequelae like encephalitis is well reported in dengue. There is growing recognition of its psychiatric manifestations like mania, psychosis and post dengue depression specially during convalescence period. We present a middle-aged male who developed mania and visual hallucinations while being managed for dengue during the convalescent phase. A 49-year-old male with 10 days of fever with positive IgM for dengue developed over talkativeness, irritability, visual hallucinations, and disinhibited behaviour during the latter part of the critical phase of the illness. There were no neurological deficits or altered sensorium during the episode. No past history or family history of mental illness. His metabolic screening and non-contrast CT brain were normal. Psychiatry opinion was taken and rapid resolution was noted after starting a small dose of olanzapine and discharged after three days of observation. He had a full recovery within the follow-up period of six weeks. Neuro-psychiatric manifestations of dengue is an emerging entity. These manifestations can be seen during the acute or convalescent phases of dengue due to the direct effect of the virus, capillary leakage or immune mediated derangements. Mood disorders are the most commonly reported psychiatric manifestations without neurological consequences. Our patient has developed psychosis during the leaking phase and it could be cytokine mediated. The pathophysiology behind neuropsychiatric manifestations of dengue remains unsorted. This will be the first reported case of dengue with psychosis in Sri Lanka. Being a dengue endemic country, this case will highlight the necessity of starting large scale studies to identify the pathophysiology of psychiatric manifestations in dengue.en-USDengueVisual HallucinationManiaPsychotic SymptomsArticle