Pseudotumoral Acute Hemicerebellitis Due to Parvovirus B19 Infection in a Child: Diagnostic Pitfalls, Successful Treatment with Intravenous Immunoglobulins and Long-Term Follow-Up

Abstract

Pseudotumoral Acute Hemicerebellitis is a very rare disease of childhood, resulting from the acute inflammation of a single cerebellar hemisphere. The clinical presentation and the neuroradiological findings strictly resembles those of posterior fossa tumors. It is regarded as a para-infectious disorder, mainly related to viral infections, albeit in almost all cases reported in the literature, the cause-effect relationship between a specific virus and this peculiar condition only relied on the recent medical history of the patient or on plasma serological tests. Molecular assays, such as Polymerase Chain Reaction has never been applied to cerebro-spinal fluid to identify the infectious agent with certainty, and among all the viruses implied, Parvovirus B19 has never been reported in the literature. Pseudotumoral Acute Hemicerebellitis requires prompt and proper medical treatment, in order to avoid the possible complications of raised intracranial pressure. Different combinations of antimicrobial agents, steroids and mannitol have been used as empirical therapy, but a very few cases of successful treatment with intravenous immunoglobulins have been reported so far. Despite usually Pseudotumoral Acute Hemicerebellitis shows a good response to therapy and a benign course, with neurological complete recovery, residual cerebellar gliosis and atrophy have been described shortly after the disease onset. Nevertheless, in all the cases reported in the literature, the clinical and neuroradiological follow-up is too short to demonstrate the long-term radiological sequelae and to establish the clinical relevance of the residual cerebellar parenchymal damage. Hereby we describe clinical presentation, diagnosis, successful treatment and long-term clinical and neuroradiological follow-up of the first pediatric case of Pseudotumoral Acute Hemicerebellitis, definitely caused by Parvovirus B19, identified in the cerebro-spinal fluid by Polymerase Chain Reaction. Citation: Bossi G, Mussati G, Fiorito I, Vanzù G, Marseglia GL (2022) Pseudotumoral Acute Hemicerebellitis Due to Parvovirus B19 Infection in a Child: Diagnostic Pitfalls, Successful Treatment with Intravenous Immunoglobulins and Long-Term Follow-Up. Arch