Hyperammonemia: Types, Causes, Symptoms, Treatment, Prognosis, Diagnosis
What is Hyperammonemia?
Hyperammonemia is a pathologic metabolic condition which is caused as a result of high levels of ammonia present in the blood. Hyperammonemia is quite serious and may be the cause of quite a few complications like encephalopathy and sometimes may even cause death. Under normal circumstances a person has anywhere between 10-40 µmol/L of ammonia in the blood, but in cases of Hyperammonemia this is markedly increased resulting in numerous life threatening complications.
What are the Different Types of Hyperammonemia?
There are basically two types of Hyperammonemia, primary and secondary.
Primary Hyperammonemia: This condition comes to the fore as a result of numerous metabolic malfunctions resulting in inactivity or reduced activity of enzymes which form a part of the urea cycle in a person.
Secondary Hyperammonemia: This condition arises from metabolic malfunctions resulting in inactivity or reduced activity of enzymes which are not a part of the urea cycle of a person. This condition is also caused due to malfunction of cells which facilitate metabolism in an individual.
What is the Cause of Hyperammonemia?
Studies suggest that Hyperammonemia is caused due to two main factors. One is that it may be caused due to processes taking place inside the body resulting in increased production of ammonia. Another potential cause of Hyperammonemia is reduction in the elimination of ammonia from the body resulting in accumulation of this gas. This can occur as a result of side effects of certain medications or medical conditions like liver failure. Some of the conditions which increase ammonia production are metabolism of protein in body and is often accompanied by gastrointestinal hemorrhage, trauma or steroid use. Medication which may increase the production of ammonia in the body is named as Glycine. This medication is utilized at the time of a surgical procedure called TURP. This facilitates production of ammonia in the body.
Stressors: Increased stress is also known to cause an increase in the production of ammonia in the body in people with known metabolic disorders.
Another form of Hyperammonemia is the idiopathic type in which there is no known or inherited cause for the disorder.
People who have conditions like herpes infections, multiple myeloma, urinary tract infection can also go on to have Hyperammonemia.
What are the Symptoms of Hyperammonemia?
Some of the symptoms that may point to Hyperammonemia are:
- Increased respirations
- Reduced muscle strength
- Babies with large fontanelles.
How is Hyperammonemia Diagnosed?
Hyperammonemia can be easily detected by conducting a blood test in case if the above symptoms are noted without another known cause. The next step is to identify the cause of the condition. For this, some of the tests conducted are:
- Liver function tests
- Measuring acetaminophen levels
- Viral serologies
How is Hyperammonemia Treated?
The basic aim of treatment for Hyperammonemia is to correct the chemical abnormalities. The first step towards this is adequate nutritional intake. It also involves taking compounds which help in eliminating nitrogen wastes from the body. These compounds react with nitrogen to form compounds which are excreted from the body and thus the increased load on the urea cycle and the enzymes involved in it is reduced. Some of the compounds used for this purpose are sodium benzoate and arginine.
In case of a baby suffering from hyperammonemic coma, then protein intake should be completely stopped, nutrition should be provided through glucose. After this, hemodialysis should be started and after this IV arginine should be started
Hyperammonemia patients with urea cycle defects may need to be treated emergently to avoid complications by stopping nitrogen products completely and starting IV sodium benzoate with checking plasma ammonium levels every eight to ten post-infusion. In case the ammonia level does not come down then hemodialysis is the way to go.
What is the Prognosis of Hyperammonemia?
When it comes to prognosis of Hyperammonemia, it is quite a serious condition and if left untreated it may result in serious disorders like encephalopathy with permanent defects. It may also cause death if not treated appropriately, although the prognosis brightens up with treatment and adequate observation for complications and prompt treatment if any complications arise due to Hyperammonemia.