In plain words
Seroconversion is the point at which a blood test changes from negative to positive for a specific infection. The test looks for antibodies, which the immune system makes after it meets an infection. Two blood samples, taken a few weeks apart, are often compared to show that the antibodies are new. In pregnancy, seroconversion matters for infections that can pass to the baby, such as cytomegalovirus and . A mother may hear the term when a test is repeated after a rash, a fever, or a known exposure. It can point to a recent infection, which is different from an infection that happened long ago. Results are read in context by the care team, because timing and the type of test both change what a result means.
The deeper version
Seroconversion is documented when an antibody test changes from negative in an early sample to positive in a later sample, most often for IgG. Interpretation depends on paired samples and on the assay's window period. For suspected congenital infection, IgM and IgG avidity testing are used together, and IgM can persist, which makes a single positive result hard to date. Maternal seroconversion during pregnancy raises the risk of vertical transmission for cytomegalovirus and toxoplasmosis. The differential for maternal lymphadenopathy and fever includes cytomegalovirus, Epstein-Barr virus, and HIV seroconversion. Kenneson and Cannon (2007) reviewed the epidemiology of congenital cytomegalovirus infection, a common cause of fetal infection and one considered when a fetal scan shows calcifications or ventriculomegaly.
Where it comes up
- Food safety: listeria, mercury, raw foodsPregnancy: Eating
- Pets, litter boxes, and pregnancyPregnancy: Your Body
What mothers here say about seroconversion
No one has posted under this term yet.
Sources
- Kenneson A, Cannon MJ — Review and meta-analysis of the epidemiology of congenital cytomegalovirus (CMV) infection. Reviews in Medical Virology 2007