Parvovirus B19, Molecular Detection, PCR
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
B19, previously classified as a parvovirus, is now in the genus erythrovirus based on preferential replication of this virus in erythroid progenitor cells.(1) Infection with B19 occurs early in life and the virus is transmitted by respiratory secretion and occasionally by blood products. Antibody prevalence ranges from 2% to 15% in early adults.(1)
B19 may result in an asymptomatic infection or produce a wide spectrum of disease ranging from erythema infections (slapped cheek syndrome or fifth disease) in children to arthropathy, severe anemia, and systemic manifestations involving the central nervous system, heart, and liver depending on the immune competence of the host.(2,3) Infection with B19 in pregnant women may cause hydrops fetalis, congenital anemia, abortion, or stillbirth of the fetus.(4) B19 is also the causative agent of persistent anemia usually, but not exclusively, in immunocompromised patients, transplant patients, and infants. The deficiencies of appropriate immune responses to B19 impair viral elimination in virus, which results in enlargement of B19-infected erythroid-lineage cells.(5,6)
Most acute infections with B19 are diagnosed in the laboratory by serologically detecting IgG and IgM class antibodies with enzyme-linked immunosorbent assay testing.
Diagnosing erythrovirus B19 (parvovirus) infection
The presence of erythrovirus B19 DNA by PCR indicates infection with this virus.
The absence of erythrovirus B19 DNA by PCR indicates the lack of infection with this virus (see Cautions).
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
A negative result does not necessarily indicate the absence of B19 infection. False-negative results may be due to suppression of virus replication to levels below the detection threshold, or to inhibitory substances that may be present in the specimens.
This assay has only been validated for the detection of genotype 1 parvovirus B19 and its ability to detect the less common genotypes 2 and 3 is unknown.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Heegaard ED, Brown KE: Human parvovirus B19. Clin Microbiol Ref 2002;15:485-505
2. Bultmann BD, Klingel K, Soltar K, et al: Fatal parvovirus B19 associated myocarditis clinically mimicking ischemic heart disease: an endothelial cell-mediated disease. Hum Pathol 2003;34:92-95
3. Rerolle JP, Helal I, Morelon E: Parvovirus B19 infection after renal transplantation. Nephrologie 2003;24:309-315
4. Chisaka H, Morita E, Yaegashi N: Parvovirus B19 and the pathogenesis of anaemia. Rev Med Virol 2003;16:347-359
5. Goto H, Ishida A, Fujii H, et al: Successful bone marrow transplantation for severe aplastic anemia in a patient with persistent human parvovirus B19 infection. Int J Hematol 2004;79(4):384-386