Congenital toxoplasmosis is a group of symptoms that occur when an unborn baby (fetus) is infected with the parasite Toxoplasma gondii.

The developing baby can become infected with toxoplasmosis if the mother becomes infected with toxoplasmosis during the pregnancy. The infection may spread to the developing baby during the pregnancy itself, or during labor or delivery.

For the mother, the toxoplasmosis infection is generally mild, and she may not be aware of it. Infection of the developing baby, however, can cause severe problems. Infection early in pregnancy results in more severe problems than later infection.

Up to half of the developing babies who become infected with toxoplasmosis during the pregnancy ae born early (prematurely). Congenital toxoplasmosis can damage the baby's eyes, nervous system, skin, and ears.

Often, there are signs of infection in the baby at birth. However, newborns with milder infections may not have symptoms or problems for months or even years. If they are not treated, almost all develop problems (especially in the eyes) when they become adolescents.

Symptoms may include:

• Enlarged liver and spleen
• Diarrhea or vomiting
• Eye damage from inflammation of the retina or other parts of the eye
• Feeding problems
• Hearing loss
• Jaundice (yellow skin)
• Low birth weight (intrauterine growth restriction)
• Skin rash (tiny red spots or bruising) at birth
• Vision problems

Brain and nervous system damage ranges from very mild to severe, and may include:

• Seizures
• Mental retardation

The health care provider will examine the baby. The baby may have:

• Swollen spleen and liver
• Yellow skin (jaundice)
• Inflammation of the eyes
• Fluid on the brain (hydrocephalus)
• Swollen lymph nodes (lymphadenopathy)
• Large head size (macrocephaly) or smaller-than-normal head size (microcephaly)

Tests that may be done during pregnancy include:

• Amniotic fluid testing and fetal blood testing
• Antibody titer
• Ultrasound of the abdomen

After birth, the following tests may be done on the baby:

• Antibody studies on cord blood and cerebrospinal fluid
• CT scan of the brain
• MRI scan of the brain
• Neurological exams
• Standard eye exam
• Toxoplasmosis test

Spiramycin can treat infection in the pregnant mother.

Pyrimethamine and sulfadiazine can treat fetal infection (diagnosed during the pregnancy).

Treatment of infants with congenital toxoplasmosis typically includes pyrimethamine, sulfadiazine, and leucovorin for one year. Infants are also sometimes given steroids if their vision is threatened or if the protein level in the spinal fluid is high.

The outcome depends on the severity of the congenital toxoplasmosis.

• Hydrocephalus
• Blindness or severe visual disability
• Severe mental retardation or other neurological problems

Call for an appointment with your health care provider if you are pregnant and think you are at risk for toxoplasmosis (for example, if you have a cat and are the person who cleans the litter box).

Call for an appointment with your health care provider if you are pregnant and have not received any prenatal care.

Prospective or expectant mothers can be tested to find out if they are at risk for toxoplasmosis.

Pregnant women who have cats as house pets may be at increased risk of developing toxoplasmosis. They should avoid contact with any materials that are potentially infected with cat feces, or that could be contaminated by insects exposed to cat feces (cockroaches, flies, etc.).

Cook meat until it is well done, and wash your hands after handling raw meat.

Petersen E. Toxoplasmosis. Semin Fetal Neonatal Med. 2007 Jun;12(3):214-23.