Molecular and clinical evaluation of the acute human parvovirus B19 infection: comparison of two cases in children with sickle cell disease and discussion of the literature

Abstract

Human parvovirus B19 is a well-known cause of severe conditions in patients with sickle cell disease, but the molecular mechanisms of the infection are insufficiently understood. The different clinical outcome of the acute parvovirus B19 infection in two pediatric patients with sickle cell disease has been examined. One of them developed life-threatening condition requiring emergency transfusions, while the other had asymptomatic infection, diagnosed occasionally. Both cases had high viral load and identical subgenotype, indicating that the viral molecular characteristics play a minimal role in the infection outcome.

Fig. 1

Phylogenetic analysis of the detected human parvovirus B19 (B19V) isolates from acutely infected and asymptomatic children with sickle cell disease. (A) Rooted NJ tree of the reference B19V genotypes and the sequences obtained from the patients with acute (AF282) and asymptomatic infections (AF262) based on a 442 bp fragment of the NS1 region. The simian parvovirus (SIM) is used as an outgroup; (B) Rooted NJ tree of the reference B19V genotypes and the sequences obtained from the patients with acute (AF282) and asymptomatic infections (AF262) based on a 699 bp fragment of the VP1 region. Simian parvovirus is also used as an outgroup. The posterior probabilities (above 75%, using 1000 bootstrap replicates) are indicated at the clusters. The statistical evaluation of some important branches was also performed by the Maximum Likelihood method (**p < 0.01 and *p < 0.05).