Materiały źródłowe

• #1 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #2 Parvovirus infection – Diagnosis & treatment – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/parvovirus-infection/diagnosis-treatment/drc-20376090

  About half of adults are immune to parvovirus infection, most likely because of a previous, unnoticed childhood infection. […] People who are at risk of severe parvovirus complications might benefit from blood tests that can help determine if they’re immune to parvovirus or if they’ve recently become infected.

• #3 Parvovirus B19 – Testing.com

  https://www.testing.com/tests/parvovirus-b19/

  To determine if you have, or recently had, a parvovirus B19 infection if you are at increased risk of complications from this viral infection; if a fetus is at high risk of contracting parvovirus B19 from a mother who is infected or has been exposed […] When a pregnant woman has a parvovirus B19 infection or has been exposed to someone with the virus; when someone, especially an immune-compromised person, has persistent or severe anemia […] A blood sample drawn from a vein in your arm for parvovirus B19 antibody testing; to detect the virus itself, the sample tested may be blood or, rarely, bone marrow; in certain cases, fetal cord blood or amniotic fluid may be collected to test for fetal parvovirus B19 infection. […] Parvovirus B19 testing is not typically used to screen the general population and is not deemed necessary in most cases of infection because symptoms are mild and time-limited. It is usually ordered to determine whether someone is currently, or has recently been, infected with parvovirus only if they are at risk of complications. It may also sometimes be ordered to determine whether someone has ever been exposed to parvovirus. Testing involves either a measurement of parvovirus antibodies—immune proteins produced in response to parvovirus B19 exposure—or the detection of the genetic material of the virus itself (its DNA) during an active infection.

• #4 Parvovirus B19 Antibodies, IgG and IgM, Serum – Logan Health Medical Center Laboratory Test Catalog

  https://logan.testcatalog.org/show/PARVS

  This test is intended for patients with at least 7 days of symptoms or asymptomatic individuals with recent exposure to parvovirus B19. […] Most acute infections with parvovirus B19 are diagnosed in the laboratory by serologically detecting IgG and IgM class antibodies to the virus using an enzyme-linked immunosorbent assay testing. […] The presence of IgM class antibodies suggests recent infection. The presence of IgG antibodies only is indicative of past exposure. […] Both IgG and IgM may be present at or soon after onset of illness and reach peak titers within 30 days. Because IgG antibody may persist for years, diagnosis of acute infection is made by the detection of IgM antibodies. […] Testing should not be performed as a screening procedure for the general population. Testing should only be done when clinical evidence suggests the diagnosis of parvovirus B19-associated disease.

• #5 Clinical Presentations of Parvovirus B19 Infection | AAFP

  https://www.aafp.org/pubs/afp/issues/2007/0201/p373.html

  Although most persons with parvovirus B19 infection are asymptomatic or have mild, nonspecific, cold-like symptoms, several clinical conditions have been linked to the virus. […] A clinical diagnosis can be made without laboratory confirmation if erythema infectiosum is present. If laboratory confirmation is needed, serum immunoglobulin M testing is recommended for immunocompetent patients; viral DNA testing is recommended for patients in aplastic crisis and for those who are immunocompromised. […] If erythema infectiosum is present, a clinical diagnosis can be made without laboratory testing. If laboratory testing is needed, there are two types of diagnostic tests to confirm parvovirus B19 infection: B19-specific antibody testing and viral DNA testing. […] Serum IgM testing is recommended to diagnose acute viral infection in immunocompetent patients, with 89 percent sensitivity and 99 percent specificity. […] Viral DNA testing is crucial for the diagnosis of parvovirus B19 infection in patients in transient aplastic crisis or in immunocompromised patients with chronic infection.

• #6 Parvovirus B19: Infection, Causes, Symptoms & Treatment

  https://my.clevelandclinic.org/health/diseases/16633-parvovirus-infection

  Parvovirus B19 is a virus that can cause symptoms like a rash and joint pain. […] Providers can diagnose parvovirus B19 using a variety of tests, including: […] A blood test can detect antibodies to parvovirus B19, which indicates whether you have or have had the disease. […] Providers can test a blood or bone marrow sample for parvovirus B19 using PCR testing or another NAT. Providers often use this to test for active infections in people with compromised immune systems. […] Talk to your provider if you have symptoms of parvovirus, especially if you’re pregnant, have a compromised immune system or have a blood disorder.

• #7 Clinical manifestations and diagnosis of parvovirus B19 infection – UpToDate

  http://www.uptodate.com/contents/clinical-manifestations-and-pathogenesis-of-human-parvovirus-b19-infection

  Clinical manifestations and diagnosis of parvovirus B19 infection […] The clinical manifestations and diagnosis of parvovirus B19 infection will be discussed here. […] DIAGNOSIS […] Diagnostic approach […] Accuracy of diagnostic techniques […] Serologic testing […] Nucleic acid detection […] Antigen detection […] Virus isolation.

• #8 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #9 Clinical Presentations of Parvovirus B19 Infection | AAFP

  https://www.aafp.org/pubs/afp/issues/2007/0201/p373.html

  Although most persons with parvovirus B19 infection are asymptomatic or have mild, nonspecific, cold-like symptoms, several clinical conditions have been linked to the virus. […] A clinical diagnosis can be made without laboratory confirmation if erythema infectiosum is present. If laboratory confirmation is needed, serum immunoglobulin M testing is recommended for immunocompetent patients; viral DNA testing is recommended for patients in aplastic crisis and for those who are immunocompromised. […] If erythema infectiosum is present, a clinical diagnosis can be made without laboratory testing. If laboratory testing is needed, there are two types of diagnostic tests to confirm parvovirus B19 infection: B19-specific antibody testing and viral DNA testing. […] Serum IgM testing is recommended to diagnose acute viral infection in immunocompetent patients, with 89 percent sensitivity and 99 percent specificity. […] Viral DNA testing is crucial for the diagnosis of parvovirus B19 infection in patients in transient aplastic crisis or in immunocompromised patients with chronic infection.

• #10 Diagnosis – GPnotebook

  https://gpnotebook.com/en-GB/pages/infectious-disease/5th-disease/diagnosis

  Diagnosis of parvovirus B19 infection is done by measuring specific IgM and IgG antibodies to parvovirus B19. […] IgM is useful in diagnosing acute infection in immuncompetent patients. […] sensitivity is 89% and specificity is 99%. […] IgM is seen 10-12 days after infection and usually persists for another 3-4 months (occasionally for a longer period). […] presence of IgG without IgM indicates previous infection of more than two months. […] in the absence of both IgG and IgM, a second serum test should be done one month after the contact date or after symptoms appear. […] B19 DNA in blood or tissue samples through PCR can be detected in serum, bone marrow and other tissues for diagnostic purposes. […] important in diagnosing parvovirus infection in patients with transient aplastic crisis or in immunocompromised patients with chronic infection.

• #11 Final Diagnosis — Case 522

  https://path.upmc.edu/cases/case522/dx.html

  FINAL DIAGNOSIS: ACUTE PARVOVIRUS INFECTION. […] Parvovirus infection is ordinarily transient with no serious sequlae, although additional support may be required in patients who develop severe anemia or aplastic crises. As such, the disease is often diagnosed clinically with no serologic or molecular confirmation needed. […] Certain populations at risk (i.e. young children with sickle cell anemia) for more severe acute parvovirus infection may require confirmation of acute infection or previous exposure status. […] Serologic diagnosis is available by ELISA and/or immunoblot assay. Parvovirus-specific IgM appears 3-10 days after clinical illness and may remain slightly elevated for several months after resolution of disease. IgG follows, typically at 7-14 days after clinical illness and in immunocompetent patients remains detectable for life.

• #12 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #13 Parvovirus – Serology | Public Health Ontario

  https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/Parvovirus-Serology

  Parvovirus serology (IgG and IgM) testing is performed daily Monday to Friday. Turnaround time is up to 5 days from receipt by PHO laboratory. […] The parvovirus testing is performed using the Biotrin Parvovirus B19 assay. The test uses chemiluminescence immunoassay (CLIA) technology for the qualitative determination of specific IgG and IgM antibodies to Parvovirus B19 in human serum or plasma samples. […] Results for Parvovirus IgG and IgM are reported as either Positive or Negative. Results may be interpreted as follows: Positive IgG and negative IgM indicate past infection; Positive IgG and IgM indicate infection within the last 7-120 days; Negative IgG and positive IgM indicate acute/recent infection; Negative IgG and IgM indicate that the patient is not immune and that no evidence of acute/recent infection is identified.

• #14 Parvovirus B19 – Testing.com

  https://www.testing.com/tests/parvovirus-b19/

  Parvovirus B19 testing is generally not used to test those with mild and uncomplicated infections. It is typically used to detect a current infection or determine immunity in those who are at an increased risk of complications, such as those with sickle cell anemia. […] Parvovirus B19 IgG and IgM antibody tests may be ordered when a pregnant female has flu-like symptoms and/or has been exposed to someone with a parvovirus B19 infection to determine if she has an active infection, had a recent infection, or has been exposed in the past. DNA testing may be performed on fetal samples in some cases. […] If both parvovirus B19 IgG and IgM are present, then it is likely that the person tested has an active, or had a recent, parvovirus infection. This can be confirmed by measuring IgG levels again 2 or 3 weeks later. […] If a parvovirus B19 DNA test is positive, then the person is currently infected with parvovirus B19. A negative result does not rule out the infection. The virus may not be present in sufficient amount in the sample to be detected.

• #15 Parvovirus – Serology | Public Health Ontario

  https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/Parvovirus-Serology

  Parvovirus serology (IgG and IgM) testing is performed daily Monday to Friday. Turnaround time is up to 5 days from receipt by PHO laboratory. […] The parvovirus testing is performed using the Biotrin Parvovirus B19 assay. The test uses chemiluminescence immunoassay (CLIA) technology for the qualitative determination of specific IgG and IgM antibodies to Parvovirus B19 in human serum or plasma samples. […] Results for Parvovirus IgG and IgM are reported as either Positive or Negative. Results may be interpreted as follows: Positive IgG and negative IgM indicate past infection; Positive IgG and IgM indicate infection within the last 7-120 days; Negative IgG and positive IgM indicate acute/recent infection; Negative IgG and IgM indicate that the patient is not immune and that no evidence of acute/recent infection is identified.

• #16 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  If a pregnant woman is exposed to parvovirus B19, obtain IgG and IgM serology as soon as possible. Note the following: Positive IgG results and negative IgM results indicate past infection (no risk to fetus). Positive IgG and IgM results indicate infection within the last 7-120 days (possible risk to fetus). Negative IgG results and positive IgM results indicate acute infection (higher risk to fetus). Negative IgG and IgM results indicate that the mother is not immune and that no evidence of acute infection is noted. In this case, repeat the tests in 3 weeks. Subsequent development of IgM indicates an acute infection. No standards have been established to evaluate parvovirus B19 PCR on maternal blood; low levels may be detected long after clinical infection. PCR may be performed on fetal serum of amniotic fluid to detect virus.

• #17 Final Diagnosis — Case 522

  https://path.upmc.edu/cases/case522/dx.html

  PCR assays for the diagnosis of parvovirus B19 are available at reference laboratories, but have not yet been FDA approved. They are, however, the test of choice for immunocompromised patients who may not be able to mount a sufficiently robust antibody response for serologic diagnosis. […] Parvovirus PCR can be positive prior to the development of the antibody response, but much will depend on the initial exposure viral load, success of invasion and replication, and speed of the serologic response making the exact number of days that PCR will detect parvovirus post-exposure prior to serologic diagnosis unclear.

• #18 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #19 Diagnosis of human parvovirus infection by dot-blot hybridization using cloned viral DNA – PubMed

  https://pubmed.ncbi.nlm.nih.gov/2983011/

  The human parvovirus can be detected in serum by the immunological techniques of immune electron microscopy (IEM), counterimmunoelectrophoresis (CIE), and radioimmunoassay (RIA). […] This test proved a highly sensitive means of detecting virus in microlitre volumes of serum, giving positive results for samples containing 0.5 pg viral DNA, equivalent to 10(4) virus particles. […] Unlike CIE and RIA the test is not affected by the presence of parvovirus-specific antibody in serum specimens, and has permitted virus to be detected in specimens obtained up to 11 days after the onset of clinical symptoms of aplastic crisis.

• #20 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #21 Clinical Presentations of Parvovirus B19 Infection | AAFP

  https://www.aafp.org/pubs/afp/issues/2007/0201/p373.html

  Although most persons with parvovirus B19 infection are asymptomatic or have mild, nonspecific, cold-like symptoms, several clinical conditions have been linked to the virus. […] A clinical diagnosis can be made without laboratory confirmation if erythema infectiosum is present. If laboratory confirmation is needed, serum immunoglobulin M testing is recommended for immunocompetent patients; viral DNA testing is recommended for patients in aplastic crisis and for those who are immunocompromised. […] If erythema infectiosum is present, a clinical diagnosis can be made without laboratory testing. If laboratory testing is needed, there are two types of diagnostic tests to confirm parvovirus B19 infection: B19-specific antibody testing and viral DNA testing. […] Serum IgM testing is recommended to diagnose acute viral infection in immunocompetent patients, with 89 percent sensitivity and 99 percent specificity. […] Viral DNA testing is crucial for the diagnosis of parvovirus B19 infection in patients in transient aplastic crisis or in immunocompromised patients with chronic infection.

• #22 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #23 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  In patients with evidence of clinically significant anemia or transient aplastic crisis (TAC), obtain a CBC count with reticulocyte count. Note the following: Patients infected with parvovirus B19 have a low reticulocyte count (0-1%). In an aplastic crisis, hemoglobin levels drop below the patient’s baseline by at least 2 g/dL. IgM antibodies are usually present by day 3 of illness or the time of hematopoietic nadir. IgG antibodies are detectable around the time of the recovery of erythrogenesis. Parvovirus B19 PCR demonstrates high level viremia during TAC. […] Immunodeficient patients with chronic B19V infection and pure red cell anemia (PRAC) also have signs of anemia. In contrast to TAC, PRAC is characterized by very low or absent antibody levels. PCR is the diagnostic test of choice to demonstrate viremia.

• #24 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  In patients with evidence of clinically significant anemia or transient aplastic crisis (TAC), obtain a CBC count with reticulocyte count. Note the following: Patients infected with parvovirus B19 have a low reticulocyte count (0-1%). In an aplastic crisis, hemoglobin levels drop below the patient’s baseline by at least 2 g/dL. IgM antibodies are usually present by day 3 of illness or the time of hematopoietic nadir. IgG antibodies are detectable around the time of the recovery of erythrogenesis. Parvovirus B19 PCR demonstrates high level viremia during TAC. […] Immunodeficient patients with chronic B19V infection and pure red cell anemia (PRAC) also have signs of anemia. In contrast to TAC, PRAC is characterized by very low or absent antibody levels. PCR is the diagnostic test of choice to demonstrate viremia.

• #25 Human Parvovirus B19 and Parvovirus Infection – Creative Diagnostics

  https://www.creative-diagnostics.com/human-parvovirus-b19-and-parvovirus-infection.htm

  The presence of giant pronormoblasts in either the bone marrow (BM) or peripheral blood can indicate a possible infection with the B19 virus. However, it is important to note that the presence or absence of these cells should not be the sole basis for diagnosing B19 infection. […] Various methods can be used to detect the B19 virus, including electron microscopy (EM), enzyme-linked immunosorbent assays (ELISAs), and hemagglutination. However, the most common approach is the isolation of viral DNA using direct hybridization or polymerase chain reaction (PCR). Direct hybridization employs a labeled viral DNA probe to bind to DNA in clinical specimens, allowing for quantifiable results and detection of all known B19 variants. PCR has increased sensitivity but requires caution to avoid contamination. Detectable DNA levels can persist in serum, synovial membranes, and bone marrow, even in healthy individuals. Therefore, low levels of B19 DNA alone are insufficient to diagnose acute infection. Moreover, multiple primer pairs should be used to avoid missing B19 variants.

• #26 Human Parvovirus B19 and Parvovirus Infection – Creative Diagnostics

  https://www.creative-diagnostics.com/human-parvovirus-b19-and-parvovirus-infection.htm

  The presence of giant pronormoblasts in either the bone marrow (BM) or peripheral blood can indicate a possible infection with the B19 virus. However, it is important to note that the presence or absence of these cells should not be the sole basis for diagnosing B19 infection. […] Various methods can be used to detect the B19 virus, including electron microscopy (EM), enzyme-linked immunosorbent assays (ELISAs), and hemagglutination. However, the most common approach is the isolation of viral DNA using direct hybridization or polymerase chain reaction (PCR). Direct hybridization employs a labeled viral DNA probe to bind to DNA in clinical specimens, allowing for quantifiable results and detection of all known B19 variants. PCR has increased sensitivity but requires caution to avoid contamination. Detectable DNA levels can persist in serum, synovial membranes, and bone marrow, even in healthy individuals. Therefore, low levels of B19 DNA alone are insufficient to diagnose acute infection. Moreover, multiple primer pairs should be used to avoid missing B19 variants.

• #27 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  If a pregnant woman is exposed to parvovirus B19, obtain IgG and IgM serology as soon as possible. Note the following: Positive IgG results and negative IgM results indicate past infection (no risk to fetus). Positive IgG and IgM results indicate infection within the last 7-120 days (possible risk to fetus). Negative IgG results and positive IgM results indicate acute infection (higher risk to fetus). Negative IgG and IgM results indicate that the mother is not immune and that no evidence of acute infection is noted. In this case, repeat the tests in 3 weeks. Subsequent development of IgM indicates an acute infection. No standards have been established to evaluate parvovirus B19 PCR on maternal blood; low levels may be detected long after clinical infection. PCR may be performed on fetal serum of amniotic fluid to detect virus.

• #28 Parvovirus B19 – Society for Maternal-Fetal Medicine

  https://www.smfm.org/parvovirus-b19

  Parvovirus B19 is a seasonal respiratory virus transmitted through respiratory droplets by people with symptomatic or asymptomatic infection. Acute parvovirus B19 infection during pregnancy can be associated with adverse fetal outcomes, including severe fetal anemia, nonimmune hydrops, and fetal demise. […] Although routine screening for parvovirus B19 immunity is not recommended during pregnancy, maternal-fetal medicine subspecialists and other obstetric care clinicians should consider serologic testing in the following situations: Pregnant people who present with symptoms compatible with parvovirus B19 infection (ie, fever, myalgia, malaise, reticular rash, and/or arthralgia following a viral illness); Pregnant people with suspected fetal anemia or nonimmune hydrops; or Asymptomatic pregnant people following confirmed exposure to parvovirus B19.

• #29 Parvovirus B19 | North Bristol NHS Trust

  https://www.nbt.nhs.uk/maternity-services/pregnancy/routine-screening-tests-scans/parvovirus-b19

  Pregnant women are not routinely screened for past parvovirus B19 infection as there is no vaccine or preventative treatment available. […] The exact number of Parvovirus B19 infections in the UK is not known as the virus does not always show symptoms, and the diagnosis can only be confirmed by blood test. […] If you have think you have been in contact with Human Parvovirus B19 infection or if you have a rash you should urgently report this to your midwife or doctor as you will need to have a blood test. […] Until parvovirus infection has been ruled out you should avoid contact with other pregnant women to reduce the risk of infecting others. […] The blood test will tell you if: You currently have Parvovirus B19 infection. […] If your results show you are Parvovirus B19 antibody negative you are at risk to infection by Parvovirus B19.

• #30 Parvovirus B19 Infection and Pregnancy: Review of the Current Knowledge

  https://www.mdpi.com/2075-4426/14/2/139

  Parvovirus B19, a member of the Parvoviridae family, is a human pathogenic virus. It can be transmitted by respiratory secretions, hand-to-mouth contact, blood transfusion, or transplacental transmission. […] Maternal diagnosis of intrauterine parvovirus B19 infection includes IgG and IgM antibody testing. For fetal diagnosis, PCR is performed through amniocentesis. […] Systematic screening for parvovirus B19 infection is not recommended, and diagnostic testing is reserved for women with high suspicion of acute infection or known exposure. Laboratory diagnosis of parvovirus B19 infection during pregnancy is mainly based on IgG and IgM antibody detection tests. […] Fetal hydrops associated with or without moderate/severe anemia in absence of a relevant cause should prompt amniocentesis followed by PCR to detect parvovirus B19.

• #31 Parvovirus B19 Infection and Pregnancy: Review of the Current Knowledge

  https://www.mdpi.com/2075-4426/14/2/139

  In pregnant women who have recently been infected with parvovirus B19, and the infection has been demonstrated, the risk of maternal–fetal transmission is high, and a close US follow-up with a specialist obstetrician must be planned. […] The tool used to determine the degree of anemia noninvasively, without the need for fetal blood sampling, is the PVS-MCA, which when elevated (>1.5 MoM) is highly suggestive of moderate/severe anemia.

• #32 Parvovirus B19 Infections | AAFP

  https://www.aafp.org/pubs/afp/issues/1999/1001/p1455.html

  The diagnosis of erythema infectiosum is made clinically, and laboratory studies are not needed under normal circumstances. Serologic tests are usually relied on for the diagnosis of parvovirus B19 infection in patients with transient aplastic crisis or arthropathy; a positive parvovirus B19specific IgM antibody or a significant rise in parvovirus B19specific IgG titer is indicative of an acute or recent infection. […] The finding of pronormoblasts on bone marrow examination of patients with anemia is suggestive of parvovirus B19 infection. Because immunocompromised patients may not be able to mount an immune response, serologic tests in these patients may not be reliable. In such situations, viral DNA isolation from the blood or bone marrow by dot blot isolation or polymerase chain reaction may be helpful.

• #33 Serology Education – Parvovirus B19

  https://serology-education.com/index-of-pathogens/viruses/parvovirus-b19

  Parvovirus B19 infection may be subclinical (25%). […] Diagnostic testing […] Presence of parvovirus DNA in blood by PCR which can be positive during the first months of infection. […] Enzyme immunoassays (=EIA) detecting parvovirus antibodies in blood. EIAs based on parvovirus B19 capsid proteins (VP1 and VP2) are the currently used antigens for detection of antibodies (sensitivities 98%). […] Testing for IgG parvovirus B19 in serum from healthy persons without symptoms of disease is optional for women of childbearing age with increased risk of infection, e.g. working in child care or elementary school. […] For diagnosis of a recent infection: IgM and IgG parvovirus B19 in serum, both a plate or automated EIAs may be used. […] For diagnosis of a chronic infection: PCR parvovirus B19 DNA in plasma or serum should be performed and IgM and IgG parvovirus B19 can be used to measure the specific antibody production.

• #34 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  In patients with evidence of clinically significant anemia or transient aplastic crisis (TAC), obtain a CBC count with reticulocyte count. Note the following: Patients infected with parvovirus B19 have a low reticulocyte count (0-1%). In an aplastic crisis, hemoglobin levels drop below the patient’s baseline by at least 2 g/dL. IgM antibodies are usually present by day 3 of illness or the time of hematopoietic nadir. IgG antibodies are detectable around the time of the recovery of erythrogenesis. Parvovirus B19 PCR demonstrates high level viremia during TAC. […] Immunodeficient patients with chronic B19V infection and pure red cell anemia (PRAC) also have signs of anemia. In contrast to TAC, PRAC is characterized by very low or absent antibody levels. PCR is the diagnostic test of choice to demonstrate viremia.

• #35 Parvovirus – Serology | Public Health Ontario

  https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/Parvovirus-Serology

  To determine acute/recent infection, during pregnancy in suspected cases of hydrops fetalis, to assess immune status following exposure to a known active case or during an outbreak investigation, during investigation of patients with aplastic crisis, and for public health purposes. […] Parvovirus IgG testing will be performed on all requests for Parvovirus serology […] Parvovirus IgG and IgM testing will only be performed when the following clinical information is provided on the General Test Requisition Form indicating acute/recent infection: onset date, symptoms. […] In suspected acute infection, IgM antibodies are detected 10-12 days after infection, and IgG antibodies are detected at 2 weeks. 90% of patients with classic erythema infectiosum rash have IgM antibodies detected at initial presentation and IgG antibodies by day 7. IgM remains detectable for months and IgG for life following recovery from acute infection. In pregnant women exposed to parvovirus B19, obtain IgG and IgM serology as soon as possible following exposure – Negative IgG and IgM results indicate that the mother is not immune and that no evidence of acute infection is noted. In this case, repeat the tests in 3 weeks. In patients with clinically significant anemia or transient aplastic crisis, IgM antibodies are usually present by day 3 of illness.

• #36 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  In patients with evidence of clinically significant anemia or transient aplastic crisis (TAC), obtain a CBC count with reticulocyte count. Note the following: Patients infected with parvovirus B19 have a low reticulocyte count (0-1%). In an aplastic crisis, hemoglobin levels drop below the patient’s baseline by at least 2 g/dL. IgM antibodies are usually present by day 3 of illness or the time of hematopoietic nadir. IgG antibodies are detectable around the time of the recovery of erythrogenesis. Parvovirus B19 PCR demonstrates high level viremia during TAC. […] Immunodeficient patients with chronic B19V infection and pure red cell anemia (PRAC) also have signs of anemia. In contrast to TAC, PRAC is characterized by very low or absent antibody levels. PCR is the diagnostic test of choice to demonstrate viremia.

• #37 Parvovirus B19 Serology: Diagnosis, Symptoms & Testing Guide – The Kingsley Clinic

  https://thekingsleyclinic.com/resources/parvovirus-b19-serology-diagnosis-symptoms-testing-guide/

  Positive IgM and IgG: This may signify an ongoing or recent infection. […] While the Parvovirus B19 serology test is a valuable diagnostic tool, it does have certain limitations. […] If the test is performed too early in the infection, antibody levels may not yet be detectable, leading to a false-negative result. […] Test results should always be interpreted in conjunction with clinical symptoms and other diagnostic findings for an accurate diagnosis. […] Parvovirus B19 serology plays a vital role in accurately diagnosing and managing infections caused by this virus. […] Understanding your test results—along with the limitations of the test—empowers you to make informed decisions about your health and overall well-being.

• #38 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #39 Parvovirus B19–Related Diseases – Viral Diseases – Infectious Diseases – Diseases – McMaster Textbook of Internal Medicine

  https://empendium.com/mcmtextbook/chapter/B31.II.18.1.10.

  Diagnosis is based on the clinical features. Diagnostic tests are usually not needed. When necessary, the diagnosis is confirmed by the following: […] In immunocompetent patients: A positive serology result; detection of parvovirus B19 IgM antibodies in serum indicates an infection within the previous 7 to 120 days; detection of a 4-fold increase of IgG also indicates acute infection. Specific IgG antibody appears within 2 weeks of infection and persists for many years (indicating a past infection). The presence of low-avidity antibodies suggests a recent infection. False-positive IgM antibodies may occur in the presence of rheumatoid factor (RF), antinuclear antibodies (ANAs), and antiEpstein-Barr virus (EBV) IgM (cross-reactivity). […] In immunocompromised patients, patients with transient aplastic crisis, or pregnant patients: Detection of parvovirus B19 DNA in blood or amniotic fluid by molecular testing (polymerase chain reaction [PCR]). Serologic tests may be negative. PCR may remain positive for 9 months after infection, and therefore is unhelpful in diagnosing acute infection. […] Bone marrow examination reveals features of hypoplasia and the presence of characteristic giant pronormoblasts.

• #40

  https://veterinarypartner.vin.com/default.aspx?pid=19239&catId=254096&id=4951462

  Recent vaccination with a live vaccine (the type of vaccine that is most effective) may interfere with the test results. This means that the test may detect the live virus from the vaccine and show a positive reading when, in fact, the puppy does not have a parvo infection. Classically, this interference occurs 5 to 12 days after vaccination so if a positive fecal ELISA test is obtained within this period after vaccination, additional tests may be recommended. […] A false negative result is possible. The puppy could be infected but no longer shedding the virus in its stool or only shedding the virus intermittently. Alternatively, the virus particles may be so thoroughly coated with antibodies that they cannot react with the tests chemicals. […] The virus essentially turns the immune system off before making its deadly way to the GI tract. This is a feature of parvovirus infection in all species, which means that a characteristic drop in white blood cell count is seen on a blood panel when the infection is active and real.

• #41 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #42

  https://link.springer.com/article/10.1007/BF03262066

  Human parvovirus B19 is the cause of a common childhood disease that usually has a mild and self-limited course. […] Selection of the diagnostic test(s) to use to detect parvovirus B19 is patient dependent. Serological testing is most appropriate in immunocompetent individuals, including children and pregnant women, who have symptoms consistent with parvovirus B19 infection or a history of recent exposure. Conversely, a molecular amplification assay should be chosen to detect parvovirus B19 DNA in individuals lacking an adequate antibody-mediated immune response. […] it is critical that clinicians are educated about the most appropriate diagnostic test to detect parvovirus B19 infection in their patients because selecting an inappropriate or inaccurate test for parvovirus B19 can lead to misinformation and/or misdiagnosis.

• #43 Erythema Infectiosum (Parvovirus B19 Infection) – Pediatrics – Merck Manual Professional Edition

  https://www.merckmanuals.com/professional/pediatrics/common-viral-infections-in-infants-and-children/erythema-infectiosum-parvovirus-b19-infection

  Erythema infectiosum is caused by acute infection with human parvovirus B19. […] Diagnosis is clinical, and treatment is generally not needed. […] For children with risk factors for complications, viral testing and complete blood count. […] For pregnant patients, antibody measurement and ultrasonography. […] The rash’s appearance and pattern of spread are the only diagnostic features; however, some enteroviruses may cause similar rashes. […] Serologic testing is not required in otherwise healthy children; however, children with a known hemoglobinopathy or immunocompromised state should have viral and/or antibody testing as well as a complete blood count (CBC) and reticulocyte count to detect hematopoietic suppression. […] In children with transient aplastic crisis or adults with arthropathy, the presence of IgM-specific antibody to parvovirus B19 in the late acute or early convalescent phase strongly supports the diagnosis.

• #44 Parvovirus B19 Infection Workup: Laboratory Studies, Imaging Studies

  https://emedicine.medscape.com/article/961063-workup

  Most patients with parvovirus B19 (B19V) infection do not require laboratory studies because symptoms are mild and the illness resolves over 5-7 days. […] Parvovirus serology (antiparvovirus B19 immunoglobulin M [IgM] and immunoglobulin G [IgG] antibodies) can be determined using enzyme-linked immunoassay (ELISA), radioimmunoassay, or immunofluorescence. Results of IgM testing are particularly difficult to interpret. Standardization between laboratories is lacking. Even in a single laboratory, sensitivity and specificity are partly determined by operator skills. High-level viremia in acutely infected persons may cause virus-antibody complexes, which will result in a false-negative IgM test result. In this setting, polymerase chain reaction (PCR) may be a better diagnostic modality. […] PCR testing for parvovirus B19 is routinely available with increased sensitivity level. However, contamination and false-positive results are noted risks that lead to confusing interpretation. Low levels of B19 DNA may detectable for more than 4 months in serum after acute infection and for years in other tissues. This test, a more useful clinical tool to diagnose chronic infection, detects viral DNA present in the blood or other tissues/fluids. The interpretation, especially as it pertains to pregnant women is uncertain. The diagnosis of acute or chronic infection should be made on the basis of standard DNA hybridization or quantitative (real-time) PCR in combination with serologic assays for B19-specific IgG, IgM, or both. Monitoring the quantitative PCR viral load in neonates with congenital parvovirus infection helps direct follow-up and the need for transfusions.

• #45 Diagnosis – GPnotebook

  https://gpnotebook.com/en-GB/pages/infectious-disease/5th-disease/diagnosis

  Diagnosis of parvovirus B19 infection is done by measuring specific IgM and IgG antibodies to parvovirus B19. […] IgM is useful in diagnosing acute infection in immuncompetent patients. […] sensitivity is 89% and specificity is 99%. […] IgM is seen 10-12 days after infection and usually persists for another 3-4 months (occasionally for a longer period). […] presence of IgG without IgM indicates previous infection of more than two months. […] in the absence of both IgG and IgM, a second serum test should be done one month after the contact date or after symptoms appear. […] B19 DNA in blood or tissue samples through PCR can be detected in serum, bone marrow and other tissues for diagnostic purposes. […] important in diagnosing parvovirus infection in patients with transient aplastic crisis or in immunocompromised patients with chronic infection.

• #46 Parvovirus B19 Serology: Diagnosis, Symptoms & Testing Guide – The Kingsley Clinic

  https://thekingsleyclinic.com/resources/parvovirus-b19-serology-diagnosis-symptoms-testing-guide/

  Diagnosing Parvovirus B19-induced aplastic anemia involves detecting IgM antibodies or viral DNA through viral serology testing. […] A Parvovirus B19 serology test, often paired with PCR testing for viral DNA, confirms the diagnosis. […] Pregnant individuals with symptoms or known exposure to Parvovirus B19 should undergo serology testing to detect IgM and IgG antibodies. […] The test’s PPV is approximately 90% in high-risk populations, making it a valuable tool for early intervention. […] The results of a Parvovirus B19 serology test provide important insights into your health. […] Positive IgM, Negative IgG: This result indicates a recent or active Parvovirus B19 infection. […] Positive IgG, Negative IgM: This suggests a past infection. […] Negative IgM and IgG: This result indicates no prior exposure to Parvovirus B19, meaning you may be susceptible to infection if exposed in the future.

• #47 Parvovirus – Serology | Public Health Ontario

  https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/Parvovirus-Serology

  Parvovirus serology (IgG and IgM) testing is performed daily Monday to Friday. Turnaround time is up to 5 days from receipt by PHO laboratory. […] The parvovirus testing is performed using the Biotrin Parvovirus B19 assay. The test uses chemiluminescence immunoassay (CLIA) technology for the qualitative determination of specific IgG and IgM antibodies to Parvovirus B19 in human serum or plasma samples. […] Results for Parvovirus IgG and IgM are reported as either Positive or Negative. Results may be interpreted as follows: Positive IgG and negative IgM indicate past infection; Positive IgG and IgM indicate infection within the last 7-120 days; Negative IgG and positive IgM indicate acute/recent infection; Negative IgG and IgM indicate that the patient is not immune and that no evidence of acute/recent infection is identified.

• #48 Parvovirus B19 Diagnosis (anti-parvovirus IgM, IgG) | Newfoundland & Labrador Public Health Laboratory

  https://publichealthlab.ca/service/parvovirus-b19-diagnosis-anti-parvovirus-igm-igg/

  Determining susceptibility to- and diagnosis of parvovirus infection in a pregnant woman exposed to a confirmed/suspected parvovirus infected individual, or presenting with signs or symptoms of parvovirus infection. […] Pregnant woman exposed to a confirmed/suspected parvovirus infected individual to determine if they are susceptible to infection (nonimmune). […] Pregnant woman who develops signs and symptoms of parvovirus infection. […] Both IgG and IgM may be present at or soon after onset of illness and reach peak titers within 30 days. Because IgG antibody may persist for years, diagnosis of acute infection is made by the detection of IgM antibodies. […] If previously stored serum is available at the PHL, Parvovirus serology may be performed, upon request, to aid in further diagnosis. […] Note: Occasionally serology results may be indeterminate. In such instances, serology should be repeated in 2-4 weeks. If the sero-profile remains the same, it likely represents non-specific reactivity, and recent exposure is unlikely.

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