Acid mucopolysaccharides is a test that measures the amount of mucopolysaccharides released into the urine either on 1 episode or over a 24-hour period.
Mucopolysaccharides are long chains of sugar molecules in the body. They are often found in mucus and in fluid around the joints.
AMP; Dermatan sulfate - urine; Urine heparan sulfate; Urine dermatan sulfate; Heparan sulfate - urine
How the Test is Performed
For the 24-hour test, you must urinate into a special bag or container every time you use the bathroom.
- On day 1, urinate over the toilet into the container or bag when you wake up in the morning. Close the container tightly. Keep it in the refrigerator or a cool place during the collection period.
- Urinate into the special container every time you use the bathroom for the next 24 hours.
- On day 2, urinate into the container in the morning again when you wake up.
- Label the container with your name, the date, the time of completion, and return it as instructed.
For an infant:
Thoroughly wash the area around the urethra (the hole where urine flows out). Open a urine collection bag (a plastic bag with an adhesive paper on one end).
- For males, place the entire penis in the bag and attach the adhesive paper to the skin.
- For females, place the bag over the two folds of skin on either side of the vagina (labia). Put a diaper on the baby (over the bag).
Check the infant often, and change the bag after the infant has urinated. Empty the urine from the bag into the container provided by your doctor.
Active babies can move the bag causing the urine to go into the diaper. You may need extra collection bags.
When finished, label the container and return it as you have been told.
How to Prepare for the Test
There is no special preparation needed.
How the Test will Feel
The test involves only normal urination, and there is no discomfort.
Why the Test is Performed
This test is done to diagnose a rare group of genetic disorders called mucopolysaccharidoses (MPS). These include, Hurler, Scheie, and Hurler/Scheie syndromes (MPS I), Hunter syndrome (MPS II), Sanfilippo syndrome (MPS III), Morquio syndrome (MPS IV), Maroteaux-Lamy syndrome (MPS VI), and Sly syndrome (MPS VII).
Most of the time, this test is done in infants who may have a symptom or family history of one of these disorders.
Normal levels vary with age and from lab to lab. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
Abnormally high levels could be consistent with a type of mucopolysaccharidosis. Further tests are needed to determine the specific type of mucopolysaccharidosis.
Jones KL, Jones MC, Del Campo M. Storage disorders. In: Jones KL, Jones MC, Del Campo M eds. Smith's Recognizable Patterns of Human Malformation. 7th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap O.