Herpes simplex encephalitis (HSE) is a relatively common sporadic central nervous
system (CNS) infection caused by Herpes simplex virus (HSV) type 1 (most often) and HSV 2
(occasionally). The final diagnosis depends on CSF PCR study to conclude the presence of the
HSV in CNS. But as this is not possible in all patients due to limited availability and precluded
in patients with raised intracranial tension, clinical and radiological features with a high index
of suspicion is the cornerstone of early diagnosis and managing this acute, potentially lethal
CNS infection. HSE presents with initial nonspecific symptoms like fever, headache followed
by rapidly evolving neurological features namely, seizures, impaired sensorium and altered
behavior which, if left untreated, may progress to coma, quadiparesis and death. Early diagnosis
and treatment with appropriate antiviral drug acyclovir can control the infection and promote
recovery, especially in elderly people who are usually severely affected by the virus due to their
comorbidities and possible immunocompromised state. Here we present an elderly woman with
essential hypertension who was admitted with symptoms of a viral fever rapidly progressing
to loss of consciousness. Her imaging features and clinical presentation was supplementated
by serological test positive for HSV 1 IgG and IgM antibody. She was promptly dealt with by
necessary medical therapy precluding CSF study for HSV- PCR due to her raised intracranial
tension. She recovered completely and uneventfully in 2 weeks. Physiotherapy was instituted.