Heterotaxy with asplenia or polysplenia, Ivemark Syndrome

From the Madisons Foundation m-Power® Rare Disease Database:

What
Heterotaxy syndrome is a disorder that results in certain organs forming on the opposite side of the body. For example, instead of the heart normally forming on the left side of the chest, it will be located on the right side. Heterotaxy has been known to affect the development of the heart, liver, lungs, intestines, and spleen. Babies with Heterotaxy syndrome are usually first identified because they have structural problems with their hearts or livers.

Who
Heterotaxy syndrome is equally common in boys and girls and can occur in all ethnic groups. For every 1,000,000 babies born, 4 of them will have Heterotaxy syndrome. Rarely, Heterotaxy can only affect the boys in some families.

Signs and Symptoms
Babies with Heterotaxy can have symptoms that start shortly after birth from any of the organs listed above. The heart is involved about 80% of the time and the first thing that may be seen is a blue color to the skin (cyanosis) that most commonly is found on the lips and under the fingernails. Over time, your baby may develop poor feeding, fast breathing, increased sweating when they eat, or poor weight gain. All of these findings are signs that the heart is not able to pump enough blood to the body to meet its needs and is called "heart failure." Sometimes your doctor might hear an unusual heart beat or an extra sound when they listen to the heart (heart murmur). Heterotaxy can also affect the liver and intestine. Biliary atresia is due to a failure of the bile ducts in the liver to form correctly and can cause jaundice (a yellow color of the skin). If the intestines are abnormally positioned inside the body, then it is more likely for the intestine to get blocked and your baby may have vomiting or swelling of their stomach when they eat. When the spleen is involved your child can have either no spleen (asplenia) or many little spleens (polysplenia). Even if there are many little spleens, sometimes they don't work well enough to help fight off certain types of infections.

Possible Causes
The exact cause of Heterotaxy is not known, but the symptoms result from the way that the internal organs turn into position during
fetal development. This rotation can be affected by many different factors including: infection, genetics, or exposures to certain chemicals. There are a few reports of families having several members with Heterotaxy, but the exact cause has not been identified yet.

Diagnosis
Making the diagnosis of Heterotaxy syndrome involves an ultrasound of the heart (echocardiogram) that will allow a pediatric
cardiologist to best see the structures of your child's heart. An electrocardiogram (EKG) is usually done to ensure there are no heart rhythm problems. An x-ray can help to evaluate the heart size and look for what side the abdominal organs and heart are on. The intestines can also be twisted incorrectly and an upper gastrointestinal series should be done to look for this. A liver-spleen scan should also be done to check for a functioning spleen. Finally, a cardiac catheterization procedure may be needed for a more detailed view of the child's heart structures in preparation for corrective surgery.

Treatment
Children with Heterotaxy syndrome and heart disease will need medications to help prevent heart failure in addition to surgery to correct the abnormalities. The type of heart surgery performed will be based on each child's particular heart problems. Children with Heterotaxy are also at increased risk of having irregular electrical signals in their heart tissue and may need a pacemaker later in life. If the intestines are twisted incorrectly, surgery will be needed to place the intestines into the proper position to prevent any blockage. When biliary atresia occurs, a liver transplant is often required. If the spleen isn't functionally properly, children with Heterotaxy will need to take daily antibiotics and receive special vaccinations to protect them from certain infections.

Prognosis
Without corrective surgery, most children with Heterotaxy syndrome and significant heart problems will not survive beyond the first year of life. If your child doesn't have many organs involved, then they can lead a fairly normal life. Even with surgery, the majority of children still face many challenges based upon their exact anatomy.