What are the other Names for this Condition? (Also known as/Synonyms)

• Duodenal Atresia TOF

What is Duodenal Atresia Tetralogy of Fallot? (Definition/Background Information)

• Duodenal Atresia Tetralogy of Fallot is a rare, inherited disorder, characterized by the coexistence of 4 heart defects and absence/under-development of duodenum, a portion of the small intestine
• The gene mutations causing Duodenal Atresia Tetralogy of Fallot have not been identified yet. The disorder is transmitted in an autosomal dominant (with variable expression and incomplete penetrance) or autosomal recessive manner

Who gets Duodenal Atresia Tetralogy of Fallot? (Age and Sex Distribution)

• Duodenal Atresia Tetralogy of Fallot is a rare congenital disorder. The presentation of symptoms may occur at birth
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Duodenal Atresia Tetralogy of Fallot? (Predisposing Factors)

• A positive family history may be an important risk factor, since Duodenal Atresia Tetralogy of Fallot can be inherited

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Duodenal Atresia Tetralogy of Fallot? (Etiology)

• The gene mutations causing Duodenal Atresia Tetralogy of Fallot have not been identified yet
• The disorder is transmitted in an autosomal dominant (with variable expression and reduced penetrance) or autosomal recessive manner

Autosomal dominant: Autosomal dominant conditions are traits or disorders that are present when only one copy of the mutation is inherited on a non-sex chromosome. In these types of conditions, the individual has one normal copy and one mutant copy of the gene. The abnormal gene dominates, masking the effects of the correctly function gene. If an individual has an autosomal dominant condition, the chance of passing the abnormal gene on to their offspring is 50%. Children, who do not inherit the abnormal gene, will not develop the condition or pass it on to their offspring.

In autosomal dominant inheritance with incomplete penetrance and variable expression, an individual may not develop symptoms even when he/she is carrying a defective gene copy in each cell of his/her body. It is believed that factors other than gene mutation(s) contribute to the development of the disease.

Autosomal recessive: Autosomal recessive conditions are traits or disorders that occur when two copies of an abnormal gene have been inherited on a non-sex chromosome. If both parents have an autosomal recessive condition, there is a 100% likelihood of passing on the mutated genes to their children. If, however, only one mutant copy of the gene is inherited, the individual will be a carrier of the condition, but will not be present with any symptoms. Children born to two carriers, have a 25% chance of being homozygous dominant (unaffected), a 50% chance of being heterozygous (carrier), and a 25% chance of being homozygous recessive (affected).

What are the Signs and Symptoms of Duodenal Atresia Tetralogy of Fallot?

The signs and symptoms of Duodenal Atresia Tetralogy of Fallot may include the presence of four heart defects, namely subpulmonic stenosis, ventricular septal defect, overriding aorta, and right ventricular hypertrophy, causing the following signs and symptoms:

• Blue discoloration of the skin (cyanosis) that can worsen when the baby cries, known as ‘blue baby syndrome’
• Clubbing of fingers, thickening of the fingertip resembling a drumstick
• Poor feeding habits
• Failure to gain weight, poor development
• Passing-out, fainting
• The child assumes a squatting position during episodes of cyanosis that make him/her feel better
• Tet spells: Episodes in infants, characterized by the skin color turning deep blue after crying, feeding, having a bowel movement, or kicking legs upon awakening. These spells are due to a rapid drop in oxygen levels in blood and are more common in young infants between the ages of 2 and 4 months

Duodenal atresia (DA), causing the following signs and symptoms:

• Abdominal swelling
• Vomiting, even on an empty stomach
• Lack of urination
• Lack of bowel movements

How is Duodenal Atresia Tetralogy of Fallot Diagnosed?

Duodenal Atresia Tetralogy of Fallot is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests
• Imaging studies
• Biopsy studies, if necessary

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Duodenal Atresia Tetralogy of Fallot?

The complications of Duodenal Atresia Tetralogy of Fallot may include:

• Dehydration
• Delayed growth and development
• Irregular heart rhythms (arrhythmias)
• Seizures during periods with lack of oxygen
• Increased risk of infective endocarditis, an inflammation of the inner lining of the heart due to a bacterial infection

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Duodenal Atresia Tetralogy of Fallot Treated?

There is no cure for Duodenal Atresia Tetralogy of Fallot, since it is a genetic condition. The treatment, including surgery, is usually given to manage the signs and symptoms and any complication that develops.

How can Duodenal Atresia Tetralogy of Fallot be Prevented?

• Duodenal Atresia Tetralogy of Fallot may not be preventable, since it is a genetic disorder
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders
• Regular medical screening at periodic intervals with tests and physical examinations are recommended

What is the Prognosis of Duodenal Atresia Tetralogy of Fallot? (Outcomes/Resolutions)  

• The prognosis of Duodenal Atresia Tetralogy of Fallot is dependent upon the severity of the signs and symptoms and associated complications, if any
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications
• Typically, the prognosis may be assessed on a case-by-case basis

Additional and Relevant Useful Information for Duodenal Atresia Tetralogy of Fallot:

The following DoveMed website links are useful resources for additional information:

http://www.dovemed.com/diseases-conditions/tetralogy-fallot/

http://www.dovemed.com/diseases-conditions/rare-disorders/