Case report: severe gastrointestinal inflammation and persistent HHV-6B infection in a paediatric cancer patient

Lymphotropic herpesviruses such as human herpesvirus type 6 (HHV-6) have enhanced pathogenicity in some immunocompromised hosts, such as transplant recipients and HIV-infected patients. The clinical relevance of HHV-6 infections in cancer patients undergoing conventional cytotoxic therapy is undetermined, however. Here we report on a 10-month-old boy with an anaplastic astrocytoma, who acquired an HHV-6 variant B infection during chemotherapy. HHV-6B infection caused or triggered severe gastrointestinal inflammation with intractable diarrhoea and failure to thrive over several months. The clinical symptoms were associated with pronounced (CD4) lymphopenia and a marked increase in serum immunoglobulin A levels. After unsuccessful therapy with ganciclovir and foscarnet, combined antiviral and anti-inflammatory treatment with cidofovir and prednisolone controlled the HHV-6 infection and enabled resolution of clinical symptoms.