The standing puzzle of Giomatosis cerebri and Herpes encephalitis

Abstract

Background & Significance: Gliomatosis cerebri (GC) is a rare brain tumor characterized by diffuse overgrowth of large portion of the brain and spinal cord by glial cells and extensive infiltration of at least two lobes. Final diagnosis is made based on a combination of biopsy and neuroimaging findings. The diagnosis remains difficult because of poor correlation of clinical, radiological, and pathological findings. Differentiation from infectious diseases, such as viral encephalitis, can be difficult or even impossible. We report a patient with GC, confused with viral encephalitis.

Case: A 33-year-old male was admitted, complaining of headache without fever. On neurological examination he had right hemiparesis, right facial pasy, and increased DTR on right side. Leukocytosis of serum and pleocytosis of cerebrospinal fluid (CSF) were observed on laboratory findings. Brain magnetic resonance imaging (MRI) showed well demarcated lesions of thalamus, midbrain, and pons in the left side and poorly delineated lesion of bilateral medial temporal lobe, more involved in the left side without enhancement. We performed [18F] fluorodeocyglucose positron emission tomography (FDG PET), in which revealed cerebral glucose hypometabolism in the corresponding areas on MRI. Biopsy findings of brain were consistent with GC.

Conclusion: He was initially misdiagnosed as viral encephalitis because this patient had some infectious signs, such as leukocytosis and pleocytosis and unclear MRI findings. However, considering the characteristic feature, discrepancy between mild clinical deficits and severe radiological findings, the diagnosis of GC should be included. It is still important enigma to diagnose GC, differentiating with viral encephalitis.