Case of parvovirus B19 infection and immunodeficiency in the patient with Gilbert syndrome

A case of long-term persistence of parvovirus B19 is described for the first time in a patient with Gilbert's syndrome against the background of immunodeficiency with predominance of infectious symptoms (chronic herpesvirus infection). Previously, the patient (male, 48 years old) was diagnosed with Gilbert's syndrome, chronic rhinosinusopharyngitis, and chronic herpesvirus infection. In July 2017, parvovirus B19 DNA was detected in blood. No clinical manifestations of infectious erythema were noted. The patient was admitted to the medical center of St. Petersburg Pasteur Institute. His blood samples obtained under informed consent were examined at the medical center in Central Clinical and Diagnostic Laboratory of St. Petersburg Pasteur Institute in January and June 2018 and in November 2019. ELISA test systems “Anti-Parvovirus B19 ELISA (IgM)” and “Anti-Parvovirus B19 ELISA (IgG)” (Euroimmune, Germany), as well PCR reagent kit “AmpliSens Parvovirus B19-FL” (FSB Central Research Institute of Epidemiology of Rospotrebnadzor, Russia) were used for specific diagnostics. Interferon status was determined by the induced production of IFN types I, II and circulating (serum) interferons. Moreover, we considered the laboratory data obtained earlier at different medical facilities of St. Petersburg. IgM class antibodies to the parvovirus B19 were not detected in the blood samples obtained in 2018. IgG antibody titer was 96 IU/ml and 264 IU /ml, respectively. Parvovirus B19 DNA was isolated from blood plasma, but the viral load was less than 720 IU of PVB19 DNA/ml (1.5 x 102 and 1.9 x 102 copies of DNA/ml, respectively). Clinical blood analysis, showed only minor (no more than 7%) deviations from the reference values, increased hemoglobin saturation of red blood cells (RBC), a decreased width of RBC distribution curve, and relative lymphocytosis. A deficiency of various interferon types was revealed: IFNγ level was 80 IU/ml in both samples, IFNα, IFNβ amounts varied from 80 to 160 IU/ml, respectively. The period of parvovirus B19 DNA persistence in blood was 11 months in presence of immunodeficiency. The patient was administered drugs of the interferon group. Parvovirus B19 DNA was not detected in clinical samples of November 2019; IFNα, IFNβ and IFNγ values were 160 IU/ml. We have detected recovery of lymphoid cell ratio, increase in their number, and improved indexes of interferon status.