Related Gene(s): CHIT1
Plasma chitotriosidase (chito) activity is a biomarker of macrophage activation and is useful for monitoring disease severity and effectiveness of treatment in Gaucher disease (GD). Clinical manifestations in GD are highly variable and cannot be predicted accurately, even when a patient’s causative gene mutations are known. Plasma levels of chitotriosidase are markedly elevated in most untreated GD patients. Determination of plasma levels of chitotriosidase has been shown to effectively confirm the diagnosis of GD (particularly when the acid beta-glucosidase levels for a patient under evaluation falls into the inconclusive range), provide early detection of disease onset and, most importantly, provide a measure of disease activity (eg, macrophage activation) that is useful for assessing the effectiveness of enzyme replacement or other therapies.
Approximately 6% of the general population (including GD patients) has a recessively inherited deficiency in chitotriosidase. A duplication of 24 nucleotides results in a deficiency allele, which can be identified by PCR analysis. Identification of the CHIT1 genotype in GD patients is necessary in order to correctly interpret chitotriosidase levels measured in plasma.
- For adults
- Blood: Two 5-10 mL tubes with EDTA (lavender top) or two 5-10 mL tubes with ACD (yellow top) from the patient.
- For newborns or children
- Blood: 2 mL in pediatric EDTA tube (lavender top) or 2 mL in pediatric ACD tube (yellow top) from patient
- Ship at room temperature
- 7-10 days