[Herpes-simplex encephalitis: case example, diagnosis and therapy].

Herpes simplex encephalitis (HSE) is the most common nonepidemic cause of acute viral encephalitis. Since successful therapy depends on a high level of suspicion that HSE is present and on the early administration of antiviral treatment, knowledge of clinical and laboratory findings of HSE is of great importance. The clinical hallmark of HSE are signs of both focal and diffuse neurologic involvement. Our case report exemplifies the diagnostic problems that can occur in HSE-patients. The validity of the different ancillary examinations is discussed. Up to the present time brain biopsy has been the method of choice for a reliable early diagnosis of HSE. In the foreseeable future early diagnosis is likely to become available in a non-invasive way by the polymerase-chain reaction. Immediate antiviral therapy with acyclovir in HSE has proved to be useful in rigorously controlled trials. The clinical picture of the acyclovir-induced encephalopathy represents a disorder that can be probably avoided by means of a sufficient hydration.