Glucosamine N Acetyl Transferase

The glucosamine N acetyl transferase blood test measures the activity of glucosamine N acetyl transferase enzyme in the bloodstream.

• The glucosamine N acetyl transferase blood test is typically done to diagnose and monitor Sanfilippo syndrome type C or MPS IIIC, a rare inherited disorder that affects the central nervous system and other organs.

• It is often used in combination with other tests, such as urine and plasma glycosaminoglycan analysis, molecular genetic testing, and clinical examination.

• It is also useful in identifying carriers of Sanfilippo syndrome type C or MPS IIIC, who have reduced enzyme activity but do not show any symptoms.

The glucosamine N acetyl transferase blood test may be recommended in the following situations:

• When a patient has signs or symptoms of Sanfilippo syndrome type C or MPS IIIC, such as developmental delay, behavioral problems, coarse facial features, hearing loss, or vision impairment. • When a patient has abnormal results from other tests, such as urine or plasma glycosaminoglycan analysis, that suggest the presence of heparan sulfate accumulation.

• When a patient has a family history of Sanfilippo syndrome type C or MPS IIIC and wants to know their carrier status.

A positive result in the glucosamine N acetyl transferase blood test may indicate low or absent activity of glucosamine N acetyl transferase enzyme. This can confirm the diagnosis of Sanfilippo syndrome type C or MPS IIIC. However, the results should be interpreted in conjunction with other clinical and laboratory findings, as some factors such as age, gender, and medication can affect the enzyme activity.

The test involves a blood draw, where a healthcare professional will collect a small sample of blood from a vein, usually in the arm. The process is safe and reasonably easy.

Patients do not need any special preparation before the test. However, they should inform their healthcare provider if they are taking any medications or supplements that may interfere with the test results.

Additional tests that may be ordered along with the glucosamine N acetyl transferase blood test include:

• Urine glycosaminoglycan analysis: To measure the amount and type of glycosaminoglycans excreted in the urine.

• Plasma glycosaminoglycan analysis: To measure the amount and type of glycosaminoglycans present in the blood.

• Molecular genetic testing: To identify the specific gene mutation that causes Sanfilippo syndrome type C or MPS IIIC.

Sanfilippo syndrome, also known as mucopolysaccharidosis type III (MPS III), is a rare and progressive genetic disorder belonging to a group of conditions known as lysosomal storage disorders. There are four subtypes of Sanfilippo syndrome, labeled A, B, C, and D, each caused by a deficiency of a specific enzyme involved in the breakdown of mucopolysaccharides (glycosaminoglycans or GAGs). Sanfilippo syndrome type C (MPS III-C) is specifically caused by a deficiency of the enzyme acetyl-CoA:alpha-glucosaminide N-acetyltransferase (HGSNAT). This enzyme is necessary for the breakdown of heparan sulfate, a type of GAG.