Parvovirus B19 encephalitis in adults: a case report from Vietnam.

Parvovirus B19 is a non-enveloped DNA virus of the Parvoviridae family, which usually causes erythema infectiosum in children. Although rare in adults, this virus can cause severe complications, including encephalitis. We report a case of a 50-year-old male patient, previously healthy, who was admitted to the hospital with high fever, headache, nausea, vomiting, and rapidly progressing to impaired consciousness. The patient was intubated and placed on mechanical ventilation. A lumbar puncture was performed, which showed mild leukocytosis with normal protein and glucose levels, and negative cultures. Tests to exclude common causes of encephalitis such as HSV, Influenza, Dengue, and HIV were all negative. Brain magnetic resonance imaging revealed corpus callosum lesions, while electroencephalography showed diffuse theta slow waves. Multiplex Polymerase chain reaction (PCR) of the cerebrospinal fluid confirmed the diagnosis of Parvovirus B19 infection. The patient was treated empirically with empirical broad-spectrum antibiotics (meropenem and vancomycin) and supportive intensive care. After seven days, the patient made a complete recovery without neurological sequelae and was discharged in a stable condition. This report emphasizes that Parvovirus B19, although generally considered a benign agent in children, can cause encephalitis in healthy adults and should be considered in the differential diagnosis of encephalitis of unknown etiology.