Thursday, September 25, 2014

Hereditary Cmv Infections

Congenital CMV Infections


Cytomegalovirus (CMV) infection can cause permanent disabilities in a small number of infants who are born with the disease. CMV is in the herpes family, related to cold sores and chicken pox. Most people become infected with the virus as children and do not have any symptoms. If a pregnant woman is exposed and infected for the first time during her pregnancy, she has a 33 percent chance of transferring the infection to her baby. If a baby is born with the virus, the infection is termed congenital.


Symptoms of Congenital CMV


One in 10 newborns infected with CMV will have problems such as fluid in the lungs, small for gestational age, low birth weight, small head size, tremors, jaundice, seizures and a rash of tiny bruises. The liver and spleen may be enlarged. Most babies who are born with these severe symptoms will suffer permanent disabilities.


Prenatal Tests for CMV


Blood titers can tell if the mother has antibodies to CMV that indicate she has been infected, but they cannot determine when the infection occurred. The baby is only at risk if the mother was infected for the first time while pregnant. There are tests that can help pinpoint the time of infection, but they are unreliable and not widely used. A woman who does not show antibodies for CMV is at risk of acquiring the infection while pregnant, but such tests are not routinely done prenatally. Amniocentesis can detect the virus but cannot tell whether the baby will have abnormalities.


Drug Considerations


Anti-viral medications such as ganciclovir, which is being experimentally tried to prevent hearing loss in the most severe cases of congenital infection, have serious side effects. They are much dangerous for use in pregnancy.


Prognosis for Babies with CMV


Most babies with CMV develop normally. Babies that have symptoms of CMV at birth may develop liver problems, growth problems, vision and hearing loss and mental disabilities later in life.


Future for CMV Research


A major development will be the discovery of a safe vaccine for CMV. Scientists are working to end the disabilities associated with CMV, which are as common as those from Down syndrome, fetal alcohol syndrome and neural tube defects.