Unusual rapid progression of glioblastoma initially mimicking herpes encephalitis

Abstract

The initial clinical and morphological manifestations of glioblastoma vary widely and can easily mimic herpes encephalitis in all radiological features, in particular if the classic necrotic tumor components are missing. We report a case of 62-year old female who presented to the emergency department with a one-month history of imbalance, dizziness, headaches and nausea. CT scan of the brain and CT angiogram were within normal limits. Lumbar puncture was negative for enterovirus, herpes simplex virus (HSV1 and HSV2) and varicella zoster virus (VZV) using polymerase chain reaction (PCR). The brain magnetic resonance imaging (MRI) showed edema involving the right mesial temporal lobe, the limbic system, the insular region and was highly suggestive of herpes simplex virus (HSV) encephalitis. The patient was treated with IV Acyclovir over 6 days and improved except for persistent confusion. Four weeks later she underwent follow up MRI because of new right 3rd nerve palsy. The MRI revealed the development of a large multifocal necrotic mass in the right temporal lobe with significant vasogenic edema and significant mass effect, including right uncal herniation, effacement of the interpeduncular fossa and compression of the right 3rd nerve. Following to the new MRI results the patient received IV corticosteroid therapy and underwent surgery. Pathology revealed glioblastoma, WHO GRADE IV, IDH 1 wildtype. This case is considered unique as its rapid progression was unusual, which emphasizes the value of doing a short-term MRI follow up in every case of clinically unproven HSV encephalitis.

Keywords

• Herpes simplex encephalitis
• Glioblastoma