Medical Causes of Intellectual Disabilities: Infections and Brain Damage

Certain types of infections can lead to intellectual disabilities. Pregnant women can take simple steps to reduce these risks. These infections are represented by the acronym TORCH. Each letter of TORCH stands for a different infection:

T- Toxoplasma infection (toxoplasmosis) is caused by a parasite. This parasite can be found throughout the world in warm-blooded animals. In the United States and Canada, cat feces are the greatest concern. It can also be introduced through undercooked meats that are infected with the parasite. The parasite can live in the ground. People may ingest the parasite by getting dirt in their mouths. This can occur during simple activities like gardening. Pregnant women should not garden, particularly in places where cats may defecate. They should not handle or clean cat liter boxes.

Toxoplasmosis is insidious in that there are no symptoms during the pregnancy. Once the child is born, the symptoms emerge. These include jaundice, rashes, and an enlarged liver and spleen. Toxoplasmosis has a profound effect on the baby's central nervous system. Unfortunately, these effects may not be recognized for months or even years. Usually this is when signs of learning disabilities or intellectual disability surface.

O- Other infections, including Hepatitis B, syphilis, and the virus herpes zoster, that causes chicken pox. Pregnant women should practice safe sex and use condoms to reduce the risk of exposure. Women planning to become pregnant should talk to their doctor about testing for these infections.

R- Rubella, the contagion that causes German measles. It is commonly associated with intellectual disabilities in infants. This insidious condition is passed from mother to baby during pregnancy. The mother's symptoms are mild, including rash and a low-grade fever. The symptoms present after birth and include intellectual disability or even death.

C- Another virus, cytomegalovirus, is so common that nearly everyone has contracted it before reaching adulthood. If the virus is contracted during teenage and young adult years, it is commonly known as mononucleosis. Cytomegalovirus may be passed from mother to fetus if she has contracted the condition for the very first time while pregnant. Five percent of babies who contract the virus have significant developmental problems including blindness and brain damage.

H- Herpes simplex II is a sexually transmitted disease. Once contracted, there is no cure. The signs are very tender blisters. The virus may remain dormant in the carrier's body until some stressor activates the virus. In this dormant state, it is not contagious. However, when blisters appear and open, it is highly contagious. An infant can contract this virus from the mother during pregnancy if the mother contracts herpes simplex virus during pregnancy. It can also be transmitted if the mother has an active outbreak during birth. The condition can be detrimental to a newborn, resulting in significant brain damage and possibly death.

Brain Damage and Intellectual Disabilities:

Several types of brain damage can lead to an intellectual disability (ID, formerly mental retardation). These are: 1) Traumatic Brain Injury (TBI), 2) congenital brain damage, and 3) progressive brain damage.

Congenital conditions are present before birth. Degenerative conditions occur after birth. They are progressive in nature. One progressive brain diseases is spinal muscular atrophy. This is an inherited neuromuscular disorder. Another is Batten disease. This is an inherited metabolic disease. It leads to the progressive decline of brain functioning.

Traumatic Brain Injuries (TBI) are injuries to the brain that occur after birth (but before age 18). Many brain injuries are preventable. These injuries may be caused by an auto accident, a blow to the head, or a fall. Children should always ride in an approved child safety seat. The seat must be installed and used correctly. Follow the manufacturer's instructions for installation and use. If a family cannot afford a safety seat, there are agencies that can provide them. Ask your healthcare provider for information. Children should always wear helmets when riding bikes, skateboards, etc.

Brain injury also occurs when infants are shaken or dropped. This unfortunate situation often occurs when caregivers are frustrated. Caring for infants can be extremely stressful. It is natural to feel frustrated. Ask your healthcare provider to refer you to someone who can teach you better ways to cope stress.