Paradoxical response to intravenous immunoglobulin in a case of Parvovirus B19-associated chronic fatigue syndrome

We describe a case of chronic fatigue syndrome (CFS) associated to Parvovirus B19 infection where administration of intravenous immunoglobulins (IVIG), previously reported as effective, induced a paradoxical clinical response and increased viral replication. The indication of IVIG administration in the treatment of Parvovirus B19-associated CFS should be carefully reconsidered.