Background: Influenza-associated encephalopathy, encephalitis, and acute necrotizing encephalopathy (ANE) are rare but potentially life-threatening neurological complications of influenza. Adult cases remain poorly characterized because the available literature is largely limited to isolated case reports and small case series. Methods: A PRISMA-guided scoping review of the MEDLINE database was conducted through 31 May 2026. Published adult cases of influenza-associated encephalopathy, encephalitis, and ANE were identified and analyzed for demographic characteristics, clinical presentation, neuroimaging findings, treatment, and outcomes. Results: Eighty-three adult cases reported between 1958 and 2026 were included. The mean age was 45.6 ± 17.8 years, and 57.8% were male. Two-thirds did not have any underlying comorbidities. Neurological symptoms developed a mean of 4.6 days after influenza onset, with influenza A accounting for 80.7% of infections. Fever (91.6%), altered mental status (86.7%), and seizures (36.1%) were the most common manifestations. Encephalitis was the predominant presentation (44.5%), followed by encephalopathy (31.3%) and ANE (24.1%). MRI most frequently demonstrated cerebral hemispheric lesions (53.0%) and bilateral thalamic involvement (36.4%), while EEG abnormalities were reported in 69.6% of patients. Overall mortality was 22.9%, highest among patients with ANE (45.0%). Among survivors, 28.9% experienced persistent neurological sequelae. Conclusions: Influenza-associated encephalopathy, encephalitis, and ANE are rare in adults but are associated with substantial morbidity and mortality. This review represents the largest adult cohort reported to date and provides important insights into the clinical spectrum, neurodiagnostic findings, and outcomes of these uncommon complications. This review highlights significant gaps in knowledge and the need for collaborative multicenter studies to improve the diagnosis, treatment, and outcome of these severe complications of influenza infection.
Burden and trends of arrhythmias in hypertrophic cardiomyopathy and its impact of mortality and resource utilization
AbstractBackgroundHypertrophic cardiomyopathy (HCM) accounts for significant morbidity and mortality worldwide. Arrhythmias are considered the main cause of mortality, however, there is paucity of data relating to trends of arrhythmia and associated outcomes in HCM patients.MethodsNationwide Inpatient Sample from 2003 to 2014 was analyzed. HCM related hospitalizations were identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD9‐CM) code 425.1 and 425.11 in all diagnosis fields.ResultsOverall, there was an increase in number of hospitalizations related to arrhythmias among HCM patients from 7784 in 2003 to 8380 in 2014 (relative increase 10.5%, P < 0.001). The increase was most significant in patients ≥ 80 years and those with higher comorbidity burden. Atrial fibrillation (AF) was the most frequently occurring arrhythmia however atrial flutter (AFL) witnessed the highest rise during the study period. In general, there was a down trend in mortality with the greatest reduction occurring in patients with ventricular fibrillation/flutter (VF/VFL). The mean length of stay was higher if patients had arrhythmia, which led to increased cost of care from $16105 in 2003 to $19310 in 2014 (relative increase 22.9%, P < 0.001).ConclusionThere is overall decline in HCM related hospitalizations but rise in hospitalization among HCM patients with arrhythmias. HCM with arrhythmia accounts for significant inpatient mortality coupled with prolonged hospital stay and increased cost of care. However, there is an encouraging downtrend in the mortality most likely because of improved clinical practice, cardiac screening and primary and secondary prevention strategies.