What Causes High Ammonia Levels In Babies?

It is not uncommon to observe elevated levels of ammonia in babies especially in newborns. This article deals with the causes of high ammonia level in babies.

Ammonia is a chemical substance that is produced in the body by breakdown of proteins. It is toxic to the body. In healthy individuals, this ammonia is converted into urea (which is non-toxic in nature) and eliminated from the body through urine. However, in the presence of certain heath issues, the ammonia level may exceed above the normal acceptable level. It, then, becomes difficult for the body to eliminate the excess ammonia from the body which in turn can lead to brain damage, coma and even death in some cases.

What Causes of High Ammonia Levels in Babies?

What Causes of High Ammonia Levels in Babies?

The most common causes of high levels of ammonia in babies are listed below:

Urea Cycle Disorders Causing High Ammonia Levels in Babies:

Urea cycle disorder (abbreviated as UCD) is a genetically inherited disorder where the baby lacks certain enzymes required by the liver to convert ammonia to urea. As a result of this, the liver is unable to convert ammonia into urea and there is excessive ammonia in the body. This condition is often noted within the first 24 hours post birth. This is one of the commonest causes of high ammonia levels in babies.

Urea cycle disorder may be accompanied by other symptoms such as irritability, tiredness and vomiting. In some children, the condition goes unnoticed and the symptoms show up later in life. Studies have shown that the child must inherit a defective gene from both parents in order to get affected by this condition. Being a genetic disease, there is no specific cure for this condition. The treatment modality mainly focuses on management of the symptoms. It is recommended to follow a low protein diet in such conditions. Medications are often prescribed to remove excess ammonia from the body.

Hemolytic Disease of Babies Causing High Ammonia Levels:

High concentration of ammonia in blood can indicate presence of hemolytic disease in newborns (also known as HDN). This condition arises from the incompatibility of the Rh factor between the child and the mother (i.e. the presence or absence of a blood protein called as Rh factor). Cases where the mother in Rh Positive and carried a child that is Rh Negative, the mother’s immune system may consider the child’s red blood cells as a foreign body and produce antibodies against it, also resulting in production of ammonia. These antibodies are usually produced during the first pregnancies but do not pose a threat till a later pregnancy. Babies born with HDN develop severe anemia. During pregnancies, if Rh incompatibility is detected, Rh immunoglobulin injections are given to the carrying mother to avoid production of antibodies which may harm the fetus. This too is one of the important causes of high levels of ammonia in babies.

Reye’s Syndrome:

This is a very rare syndrome that affects children and young adults causing encephalopathy (or brain dysfunction), liver degeneration, reduced glucose level and higher levels of ammonia in the body. This is a one of the known causes of high levels of ammonia in babies too. The cause of this condition is linked to use of aspirin during viral infections like chicken pox. There is no specific treatment for this condition. Treatment modalities aim towards controlling symptoms such as controlling intracranial pressure, controlling seizures, management/prevention of liver damage etc. Studies have shown that about 1/3rd of children and teenagers who develop Reye’s syndrome suffer from permanent neurological damage or die soon.

Other Causes of High Ammonia Levels in Babies:

There are other causes which may lead to over production of ammonia in the body. Since, liver is the vital organ that converts ammonia to urea for elimination from the body, any damage to the liver can cause elevated level of ammonia in the body. Hence, such conditions too can be some of the causes of high levels of ammonia in babies. Conditions associated with bleeding in the digestive tract (gastrointestinal bleeding) may cause excessive ammonia production by breakdown of red blood cells in the intestine followed by release of protein in the blood stream. Babies who have renal failure also have high ammonia level in the body. As the body is unable to eliminate urea efficiently, there may be accumulation of ammonia in the body.


Thus, it is clear that there are many causes of high levels of ammonia in babies and proper diagnosis is needed. If a baby is detected with high ammonia levels, it is very essential that appropriate medical care and treatment is provided as an emergency. An increased level of ammonia is very toxic for the body and thus can lead to several major health concerns including coma, brain damage and in severe cases it can also lead to death. Thus, once the symptoms are noticed, there must not be any delay in seeking medical help.

Also Read:

Team PainAssist
Team PainAssist
Written, Edited or Reviewed By: Team PainAssist, Pain Assist Inc. This article does not provide medical advice. See disclaimer
Last Modified On:January 8, 2022

Recent Posts

Related Posts