IntroductionPost-infectious cerebellitis is an acute form of inflammatory encephalitis mainly limited to the cerebellum. It is commonly found in children, especially after viral infections such as Epstein-Barr virus. Post-infectious cerebellitis presents with acute onset dysarthria and ataxia. To the best of our knowledge, this is the first case report of post-infectious cerebellitis in a patient with both dengue and Epstein-Barr viral infection confirmed on serology.Case presentationA 43-year-old Sri Lankan Sinhala man presented with an acute febrile illness associated with thrombocytopenia. While being managed as uncomplicated dengue fever, our patient developed dysarthria, ataxia and cerebellar signs. Our patient's infectious disease screen was positive for both dengue and Epstein-Barr specific immunoglobulin M. A cerebrospinal fluid analysis was suggestive of viral meningoencephalitis while cerebrospinal fluid serology was positive for dengue immunoglobulin G. T2-weighted magnetic resonance images were consistent with post-viral cerebellitis. The patient was given full supportive care and he made an uneventful complete recovery.ConclusionThere have been no previously reported cases of post-infectious cerebellitis associated with both Epstein-Barr and dengue viral infections confirmed by serology. Our patient's clinical features and findings on the imaging studies were consistent with post-viral cerebellitis. This report highlights the need to screen for other possible more common etiologies of a particular presentation before coming to a specific diagnosis based on initial findings. Uncomplicated cases of cerebellitis can be successfully managed with appropriate supportive measures with good prognosis, as in this case.