Identification and characterization of acute infection with parvovirus B19 genotype 2 in immunocompromised patients in Poland.

Parvovirus B19 (B19V) is divided into three genotypes. Genotypes 2 and 3 may cause diagnostic difficulties and their epidemiology is not well understood. In the present study the prevalence of B19V genotypes in patients with symptomatic infection in Poland was evaluated and the course of infection in patients infected with non-genotype 1 strains is described. Real-time PCR, able to detect all three genotypes of B19V was used to screen patient plasma samples. Sixty-nine, mainly acute-phase B19V DNA positive cases were identified in patients from hematological and obstetric/gynecological wards between 2004 and 2008. Thirty patients were studied in greater detail and genotyping was performed by analysis of the NS1/VP1u region. The majority of samples were genotype 1. However two (6.6%) strains were identified as genotype 2, associated with high viremia and identified in a kidney transplant recipient with anemia and a leukemia patient, following chemotherapy, with pancytopenia. A change of immunosuppression treatment in the former and treatment with intravenous immunoglobulin in latter, resulted in normalization of clinical parameters, and whilst viral loads fell, B19V DNA was still detectable. The kidney transplant recipient subsequently became pregnant with no clinical complications, although persistently infected with B19V genotype 2. This is the first description of symptomatic cases of genotype 2 B19V infection in Eastern Europe suggesting that acute infection, particularly among immunocompromised patients with these virus strains may be more prevalent than thought.