ABSTRACT

Herpes simplex encephalitis is the most common form of acute encephalitis. Untreated Cases have a mortality of 70%. In early diagnosis, herpes simplex virus positivity in cerebrospinal fluid and magnetic resonance imaging is important. Rarely, as seen in our case, HSV positivity is not detected in CSF analysis diagnosed with clinical and radiological images. A male patient, who was 44 years old, was examined because of fever, headache, confusion and generalized seizures. He had somnolence, limited cooperation, neck stiffness, and fever of 38°C. There was dysarthria in speech and he had difficulty finding words. Examination of CSF leukocyte revealed 1-2, 15-20 red blood cells and a slight increase in protein. In diffusion MRI, hyperintensity was observed in the anterior left temporal lobe. Despite a lesion which spread to the frontal lobe on repeated MRI, repeated early and late period serum and CSF tests for HSV type 1-2 IgM-IgG and HSV type 1-2, the PCR result was negative. Clinical history and radiological images suggest probable herpes encephalitis from which the patient recovered without sequelae with antiviral therapy. Today, the PCR method is considered the gold standard in the diagnosis of herpes encephalitis. However, when the disease is suspected following clinical tests and radiological images,, even if there is PCR negativity, early treatment can be life saving. (JAREM 2012; 2: 29-32)

Keywords: Encephalitis, herpes simplex virus, polymerase chain reaction, cerebrospinal fluid, imaging, prognosis