Title : Clinico-epidemiological presentation of acute encephalitis syndrome in patients visiting a tertiary hospital in Kathmandu, Nepal: A descriptive cross-sectional study
Acute encephalitis syndrome (AES) is defined as acute onset of fever and a change in mental status (including symptoms such as confusion, disorientation, coma or inability to talk) and/or new onset of seizures (excluding simple febrile seizures) in a person of any age at any time of year. It is a complex, severe, neurological syndrome that is associated with significant morbidity and mortality and often it is associated with meningitis. Etiologies include viral, bacterial, rickettsial, fungal, parasitic, para or post infectious and antibody associated or those associated with paraneoplastic syndrome. In most cases, the cause of encephalitis is unknown. Specific etiologies are identified in less than 50% of cases. It usually presents with fever and altered sensorium (confusion and behavioral abnormalities) or depressed level of consciousness ranging from mild lethargy to coma. It may also present with seizures (focal or generalized), focal findings like aphasia, ataxia, weakness of extremities and cranial nerve deficits (ocular palsies, facial weakness). Meningism can be seen if there is associated meningitis. Diagnosis is made by the clinical picture, laboratory investigations (blood and CSF samples) and radiological imaging.
Acute encephalitis syndrome (meningitis, meningoencephalitis, encephalitis) is a cause of significant morbidity and mortality in Nepal. Not only Nepal, it is a burden worldwide with annual incidence estimated to be 0.07 to 12.60 cases per 100,000 population. Encephalitis represents a challenging condition for physicians to evaluate and to treat given the variability of its presentations and etiologies and low diagnostic yield. In limited resources setup, especialy like that of Nepal, initiation of empirical treatment post suspicion is of great importance than treatment post definitive diagnosis. My research would be of great aid in suspicion of AES. The true incidence of these infections is difficult to determine because the diagnosis may not be considered, many cases are unreported, or a specific viral etiology is never confirmed. Thus, my research would help in categorising the possible cases of AES. As observed in my study, AES often results in an increased number of cases with unknown etiology due to its poor diagnostic yield. We, thus, can conclude that diagnostics for acute encephalitis syndrome require a significant amount of resources, however, standard protocols can be incorporated to identify AES. To standarise such protocols, studies like mine will prove to be of great value. Future studies should include participants from multiple centers worldwide and analyze the clinical spectrum. Periodic hospital-based epidemiological investigations essential to determine the spectrum of agents that cause AES, similar to what my research offers; the information can be used to develop preventive measures against specific etiologic agents.