Study researchers proposed a case definition for acute fulminant brain edema (AFCE) based on a clinical profile of patients from the California Encephalitis Project (CEP). This is evident from study results published in the Journal of the Pediatric Infectious Disease Society.
The study researchers reviewed the medical history of all pediatric patients with cerebral edema who had been referred to the CEP between 1998 and 2012 and who had progressed to fulminant cerebral edema. The case definition is designed to include fever, altered mental status, and / or new seizures, followed by progression to diffuse brain edema, as documented by neuroimaging and / or autopsy.
The study researchers differentiated known causes of cerebral edema by excluding patients with a history of epilepsy, organic brain injuries, metabolic disorders, or neurological disorders, and those with serum sodium less than 130 meq / L. They also excluded patients with neurological signs and symptoms as a side effect.
All AFCE patients had a fever and most had new seizures (24; 80%) and / or altered mental status (25; 83%). Of the 24 patients aged 4 years and over, 19 (79%) had a headache. Almost all patients (28; 93%) had upper respiratory tract (URT) and / or gastrointestinal (GI) symptoms. Of this group, 11 showed both URT and GI symptoms, 3 only URT symptoms and 14 only GI symptoms (11 of which had vomiting without diarrhea).
Of 1955 pediatric patients, 30 met the AFCE case definition. Gender was borderline statistical significance in AFCE patients as 63% were girls while 46% of non-AFCE patients were girls (P = 0.06). A larger proportion of AFCE patients were Asian or Pacific islanders (44%) compared to non-AFCE patients (14%; P <0.01). Mortality in AFCE patients was also significantly higher than in non-AFCE patients (80% versus 13%; P <0.01).
Of the 12 AFCE cases that indicated an acute infection, 2 met the CEP criteria as confirmed causes (enterovirus, human herpes virus type 6), while 10 had other indications of a pathogen in the respiratory tract.
AFCE seems unusual, and colleges would likely only have 1 or 2 cases every few years. The etiology likely involves both genetic and environmental factors, according to the study’s researchers. A wide range of therapies were provided by attending physicians, and no specific treatment was associated with an improved outcome.
Additionally, avoiding hyperthermia in AFCE patients may be “beneficial” because AFCE shares clinical and demographic similarities with influenza-related neurological complications.
Limitations include those that, due to their retrospective nature and CEP referral, are likely to target more severe and diagnostically demanding cases, which limits representation of all encephalitis patients.
“We suspect that not a single pathogen is responsible for the development of AFCE, but that a certain number of relatively common infections can trigger this phenotype in certain people,” the researchers concluded.
Krishnan P., Glenn OA, Samuel MC, et al. Acute fulminant brain edema: a newly recognized phenotype in children with suspected encephalitis. J Pediatric Infect Dis Soc. 2021; 10 (3): 289- 294. doi: 10.1093 / jpids / piaa063