Acute Fulminant Cerebral Edema in a Child With Suspected Meningoencephalitis

Abstract

Acute fulminant cerebral edema (AFCE) is a recently identified encephalitis type associated with significant morbimortality. Described as rare, limited data exists on its early detection and treatment. This paper describes a case of AFCE that progressed to unresponsive intracranial hypertension. A previously healthy four-year-old boy presented with fever, myalgias, and neurological symptoms. Diagnostic assessments showed cerebrospinal fluid abnormalities, and despite medical interventions, his condition deteriorated rapidly and developed severe cerebral edema and herniation within 24 hours. A decompressive craniectomy was attempted to decrease intracranial pressure, without success. This case emphasizes the urgency of early AFCE recognition and effective management strategies given its severe prognosis, aiming to improve understanding and spur further research.

Keywords: acute encephalitis; acute fulminant cerebral edema; decompressive craniectomy; hyperosmolar therapy; secondary intracranial hypertension.

Figure 1. Head computed tomography scan revealing diffuse hypodensity of the brain parenchyma (diffuse dark areas), involving the cortico-subcortical parenchyma, the basal ganglia, and the thalamus.

Figure 2. Head computed tomography scan showing a global effacement of the cerebrospinal fluid circulation spaces of the hemispheric sulci, convexity and basal cisterns, as well as a global loss of differentiation between gray and white matter in the supratentorial compartment (a and b). These findings are compatible with diffuse cerebral edema. After administration of contrast (red arrow on c), leptomeningeal contrast uptake is observed.

Figure 3. Head computed tomography imaging revealing pronounced global hypodensity in both cerebral hemispheres, absence of grey and white matter differentiation and complete effacement of the extra-ventricular supratentorial spaces.

The brainstem mass effect is more exuberant, with a notable mesencephalic compression due to bilateral uncal herniation (green arrow on c). There is also a greater conflict of space in the posterior fossa. Brain parenchyma is herniated through the site of the bilateral frontal craniectomy. An intracranial pressure monitoring catheter (yellow arrow on a) is placed in the anterior horn of the right lateral ventricle.