Neonatal encephalitis through human parechoviruses with signs of extensive white matter injury – Case study and comparison to existing published cases

Parechoviruses are enteroviruses, which have only recently been detectable with PCR and can be described as a causative agent for neonatal encephalitis. We are reporting on a newborn with encephalitis and extensive white matter injury, a type of case on which there are very few publications to date.

The female baby was born by normal spontaneous delivery after an uncomplicated pregnancy. The baby showed no clinical signs of problems, except for a hoarse throat on the fourth day. On the seventh day the baby briefly developed a fever of 39.1°C and therapy-resistant myoclonic seizures. Because of central apnea, the baby was on artificial ventilation for several days. The initial IL-6 was slightly high, at 125 pg/ml, the C-reactive protein (CRP) was persistently normal. Cerebrospinal fluid showed no pleocytosis or elevated protein concentration. The infection serology results, including the PCR for enteroviruses in the stool and cerebrospinal fluid, were negative. The cerebral MRI findings revealed widespread symmetrical high signal intensity on T2 weighted imaging and restricted diffusion in white matter from the frontal to the occipital, as well as in the corpus callosum, internal capsule and pyramidal tract. In addition, there were spots with increased intensity spread over the periventricular white matter. Initially, differenzial diagnosis suggested a damage due to ischemia. However, no underlying causes could be identifical.

Parechoviruses were detected with PCR in the stool and cerebrospinal fluid. (Institute of Virology, University of Bonn, Prof. Drosten).

The course, supported also by the magnetic resonance imaging (MRI) findings, fits well with the published cases (Malgorzata 2008) from neonatal encephalitis through parechoviruses. Seizures, irritability and increased temperature without detection of pleocytosis and white matter injury in the MRI are typical in the first two weeks. By this constellation of symptoms, the stool and fluid should be studied for parechoviruses (PCR) in addition to the classical neurotropic viruses.