Overview
Influenza infection can complicate neurological presentations, particularly in patients with pre-existing central nervous system (CNS) disorders, potentially leading to secondary CNS complications such as encephalitis or meningitis.Diagnosis
Clinical Presentation: Focus on signs of altered mental status, focal neurological deficits, severe headache, and vomiting 1.
Imaging: Cranial CT recommended for patients with high suspicion criteria (age ≥60 years, focal neurologic deficit, headache with vomiting, altered mental status) to detect significant abnormalities like stroke, intracranial bleeding, or infection 1.
Biopsy and Immunohistochemistry: In cases where CNS tumors are suspected, immunohistochemical staining for neuron-specific enolase (NSE) can be useful but should be interpreted cautiously, especially in non-APUD tumors 2.Management
Antiviral Therapy: Oseltamivir or zanamivir are first-line treatments for influenza; dosing varies by age and clinical condition but generally follows standard guidelines [Not specified in provided abstracts].
Supportive Care: Management includes hydration, fever control, and monitoring for complications such as secondary infections or worsening neurological symptoms [Not specified in provided abstracts].
Neurological Support: For patients with CNS disorders, close monitoring and tailored interventions based on specific neurological deficits are crucial [Not specified in provided abstracts].Special Populations
Elderly: Higher suspicion for significant CT abnormalities; imaging criteria apply similarly but with increased vigilance 1.
Comorbidities: Patients with pre-existing CNS disorders require heightened clinical scrutiny and prompt imaging if neurological signs are present 1.Key Recommendations
Order cranial CT scans in elderly patients (age ≥60 years) or those presenting with focal neurologic deficits, headache with vomiting, or altered mental status, given the high sensitivity for detecting clinically significant abnormalities 1 (Evidence: Moderate).
Use immunohistochemical staining for neuron-specific enolase cautiously in diagnosing CNS tumors, recognizing its limited value in non-APUD tumors 2 (Evidence: Weak).
Implement supportive care measures tailored to the severity of influenza and the presence of neurological symptoms, emphasizing close monitoring in special populations [Not specified in provided abstracts] (Evidence: Expert opinion).References
1 Rothrock SG, Buchanan C, Green SM, Bullard T, Falk JL, Langen M. Cranial computed tomography in the emergency evaluation of adult patients without a recent history of head trauma: a prospective analysis. Academic emergency medicine : official journal of the Society for Academic Emergency Medicine 1997. link
2 Vinores SA, Bonnin JM, Rubinstein LJ, Marangos PJ. Immunohistochemical demonstration of neuron-specific enolase in neoplasms of the CNS and other tissues. Archives of pathology & laboratory medicine 1984. link