Abstract
BACKGROUND: Chikungunya is a mosquito-borne viral infection, which classically presents with the triad of acute onset of fever, rash, and debilitating arthralgia. Although musculoskeletal symptoms are predominant, it is increasingly recognized that chikungunya virus infection can present with neurological complications involving both the central and peripheral nervous systems via mechanisms that include direct viral invasion and immune-mediated responses. CASE PRESENTATION: In this report, we describe five adult patients with confirmed chikungunya infection who presented with a wide spectrum of neurological complications. Chikungunya virus (CHIKV) real-time reverse transcription-polymerase chain reaction (rt RT-PCR) and IgM in cerebrospinal fluid (CSF) and blood were performed in all patients, and supportive imaging and neuroelectric studies were done as clinically indicated. Three patients were diagnosed with CHIKV-associated encephalitis, each presenting with distinct clinical features such as seizures, myoclonus, and altered levels of consciousness. CHIKV rt RT-PCR was positive in CSF of all patients, confirming direct viral invasion of the central nervous system. Among the remaining two patients, one presented with bilateral facial nerve palsy and ataxia, consistent with an atypical variant of Guillain-Barré syndrome (GBS). The other patient developed memory impairment following resolution of the acute febrile illness, suggestive of post-infectious cognitive dysfunction. Both cases likely represent immune-mediated sequelae of chikungunya infection. In the absence of specific antiviral therapy, all patients were managed supportively. CONCLUSION: This case series, the first report from Sri Lanka, highlights the broad neurological manifestations of CHIKV infection. Enhanced clinical vigilance and timely neurodiagnostic evaluation are essential in managing these patients. Therefore, raising awareness among the medical community regarding the broad spectrum of neurological manifestations is critical in combating this emerging clinical challenge.