Dose-by-dose virological and hematological responses to intravenous immunoglobulin in an immunocompromised patient with persistent parvovirus B19 infection

A 42-year-old male with stage IV mantle cell lymphoma received chemotherapy and autologous peripheral blood stem cell transplantation. He developed pancytopaenia, and bone marrow examination indicated a parvovirus B19 (PVB 19)-induced red cell aplasia, confirmed by virological tests. Multiple doses of intravenous immunoglobulin (IVIG) were given over the following months, with blood samples being taken after each dose for quantitative PVB 19 DNA and hematological testing to assess the response. Each dose of IVIG produced a 1-3 log(10) drop in PVB 19 DNA levels. Eventually, after the fifth dose of IVIG, the PVB 19 DNA was reduced to <10 copies/ml serum, with a gradual improvement in his hematological parameters. This report demonstrates how close monitoring of the virological and hematological response to IVIG therapy for persistent PVB 19 infection in an immunocompromised patient can optimize the usage of this relatively expensive, and sometimes scarce intervention.

Parvovirus B19 infection in Hong Kong

Human parvovirus B19 is a small DNA virus that can cause a number of diseases, notably erythema infectiosum in children, and aplastic crisis in patients with chronic haemolytic disorders. With the availability of serological tests for parvovirus infection, much is known about the prevalence of this virus in the Western population. However, there have not been any data on the epidemiological pattern of parvovirus B19 infection in Hong Kong and its surrounding region. In this report we have studied the sero-prevalence of parvovirus B19 in Hong Kong in 1983 and 1993, and were able to show a low incidence of parvovirus infection in the intervening 10 years, leading to a shift in the prevalence rate of parvovirus infection in the general population. From 1991 to 1996, of 276 patients presenting with illness which might have been caused by B19, only 2.5% were positive for IgM and 19.6% for IgG anti-B19. The prevalence of IgG anti-B19 among patients with thalassaemia major requiring frequent blood transfusion in 1995 was similar to those in the same age group in the general population, substantiating the observation that B19 infection was not common in Hong Kong in recent years.