Hi and welcome to the cirrhosis community.
The blood ammonia test, NH3, has a normal range of "about" 10 to 80 mcg/dL.(micrograms)
Note: Lab ranges vary so be sure to look at YOUR lab's range levels.
Ammonia levels rise when there are large amounts of protein being catabolized and the liver is unable for some reason to convert it into urea so it can be excreted through the kidneys. anything that interferes with the breakdown of ammonia in the system will increase serum levels.
Also keep in mind that it is the symptoms of hepatic encephalopathy that are used to diagnose HE. This is especially important for caregivers as they may be able to recognize the symptoms which the cirrhotic may be completely oblivious to due to the impact the HE has on our brain function.
The severity of HE is judged according to your symptoms. The most commonly used staging scale of Hepatic Encephalopathy is called the West Haven Grading System:
Grade 0: Minimal HE
This stage is very hard to detect as changes in your memory, concentration and intellectual functioning are so minimal that they may not be outwardly noticeable, even to you. Coordination can be affected and although subtle, may impact your ability to drive a car.If you recently had poorer performance at work or have committed a number of traffic violations while driving, it would be worth bringing this to the attention of your healthcare provider. You may be referred for special testing, called neuropsychiatric testing, to evaluate your thinking abilities by doing a number of specifically designed tasks with a trained examiner. If your test reveals some deficits, your healthcare provider will likely schedule frequent follow-up visits to closely follow your condition. There are currently no medications approved by the FDA to treat minimal HE.
Grade 1: Mild HE
You may have a short attention span, notice mood changes like depression or irritability, and have sleep problems.
Grade 2: Moderate HE
You may keep forgetting things, have no energy and exhibit inappropriate behavior. Your speech may be slurred and you can have trouble doing mental tasks such as basic math. Your hands might shake and you can have difficulty writing.
Grade 3: Severe HE
You may be confused as to where you are or what day it is and be extremely sleepy, but can still be woken up. You may be unable to do basic mental tasks, feel extremely anxious and act strangely.
Grade 4: Coma
The last stage of HE is when the person becomes unconscious and slips into a coma. (This is a life-threatening emergency situation and the person should be taken to an ER ASAP.)
I hope this helps answer your question.
Hi jd. Not sure if this will help but I asked my Hepatologist at Mayo Clinic about testing for ammonia in the blood on Friday. I have cirrhosis and have never had my blood tested for it. My Hepa stated that you could have let's say 0 levels and have full fledged HE, or score in the 100s and be perfectly fine. There they find the scores unreliable and don't test the blood.
On the other hand they only use the test that Hector pointed out the neurophysiatric test. As mentioned it's a diagnostic tool done by a specialist to diagnose and treat HE.
Best to you