Comments
INITIAL SYMPTOMS:
Rash; Fever is low grade or absent. [CCDM]
FINDINGS:
Erythema infectiosum (EI) is a common rash in children with "slapped cheeks" of the face and a fine, lacy rash of the trunk. The rash may last for 1-3 weeks, and the disease is typically mild and without fever. The virus replicates in red blood cell precursors, and complications of the disease are seen in patients with hemolytic anemia, immunosuppression, or pregnancy. B19 parvovirus infections cause aplastic crises in patients with sickle cell disease, thalassemia, hereditary spherocytosis, and other hemolytic diseases. Immunosuppressed patients may develop severe anemia. [CCDM, p. 202-4; ID, p. 1959-66] Childhood infections are most common in the spring months, and a low-grade fever is typical. Infected adults may experience mild joint pain and swelling that persists for weeks or months. [Merck Manual, p. 2840] "Glove-and-sock syndrome, an exanthem localized to the hands and feet and consisting of edema, erythema, paresthesia, and pruritis, has been linked to B19." [Cecil, p. 2116] The incidence of EI peaks in children ages 4-12. Adult women are more likely to have arthritis. The following are associated but not proven complications: glomerulonephritis, hepatitis, thrombocytopenic purpura, meningoencephalitis, myocarditis, and pericarditis. [5MCC-2015] Adults do not typically have the "slapped cheek" rash. [Harrison ID, p. 817] Recent studies using molecular techniques (PCR) have implicated parvovirus B19 in 56% of 87 patients with viral myocarditis. [Cohen, p. 505] Based on case reports and PCR detection with poorly documented controls, there are a number of associated conditions including glomerulonephritis, hepatitis, encephalitis, and meningitis. Rare skin presentations are vesiculo-pustular, papular-purpuric glove and sock syndrome, and erythema multiforme. Brachial plexus neuropathy with weakness has been reported. Transient liver enzyme abnormalities are common, but hepatitis is rare. [PPID, p. 1843-4]
EPIDEMIOLOGY:
Epidemics occur in winter and spring in temperate climates. Transmission by transfusion has been reported. [CCDM] Seropositive rates are >50% for children (15 and older) and >90% for elderly adults. [Harrison, p. 712] "Maternal B19 infection between 9 and 20 weeks’ gestation may carry a significant risk for developing fetal anemia." [5MCC-2015] Patients with immunodeficiency may have persistent parvovirus infection because of failed antibody response. Pure red cell aplasia is one of the presenting diseases in AIDS patients. Anemic crises in patients with hereditary spherocytosis or sickle cell disease are almost always caused by B19 parvovirus infections. [Cecil, p. 2115]
PREVENTION:
"Personnel have acquired infection while working in laboratories or during the care of patients with B19-associated sickle-cell aplastic crises. . . . Persons with erythema infectiosum are infectious before the appearance of the rash, those with infection and aplastic crises for as long as 7 days after onset of illness, and persons with chronic infection for years. . . . Because of the serious nature of the consequences for the fetus, female personnel of childbearing age need to be counseled regarding the risk of transmission of B19 and appropriate infection control precautions." [Guidelines for Infection Control in Health Care Personnel. CDC. 1998]
For updated text and symptoms of infectious diseases, see iddx.com.
Diagnostic
Clinical; IgM antibodies (85% sensitive; turn negative in <3 months); IgG (from 2 weeks post infection to lifelong); Giant pronormoblasts in blood or bone marrow are suggestive; PCR most sensitive, but not diagnostic alone; [ABX Guide]