Plasma chitotriosidase (chito) activity is a biomarker of macrophage activation and is useful for monitoring disease severity and effectiveness of therapy in treatment of 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" (i.e. 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. The deficiency allele can be identified by PCR analysis, where the active allele results in a 75 nt product and the null allele produces a 99 nt PCR amplicon. Identification of the CHITO genotype in each GD patient (75/75, 75/99, 99/99) is necessary in order to correctly interpret chitotriosidase levels measured in plasma.
1. Hollak, C.E.M., van Weely, S. van Oers, M,H.J., and Aerts, J: Marked elevation of plasma chitotriosidase activity: A novel hallmark of Gaucher disease, J,. Clin Invest, 93:1288-1292, 1994.
2. Aerts, J., Boot, R, Renkema, G.H., van Weeley, S, Jones, S., Hollak, C., van Oers, Molecular and biochemical abnormalities of Gaucher disease: Chitotriosidase, a newly identified biochemical marker, Seminars in Hematology, 32:3 (Suppl 1), 10-13, 1995.
3. Boot, R., Renkema, G.H., Verhoek, M., Strijland, A., Bliek, J., de Meulemeester, T., Mannens, M., Aerts, J.M.F.G., The human chitotriosidase gene: nature of inherited enzyme deficiency, J Biol Chem, 273(40):25680-25685, (1998).
4. Guo, Y., He, W., Boer, A., Wevers, R., De Bruum, A., Groener, O., Hollak, C., Aerts, J., Galjaard, H. and van Digggelen, O.P., Elevated plasma chitotriosidase activity in various lysosomal storage disorder, J. Inher. 18:717-722 (1995).
5. Young, E., Chatter ton, C., Vellodi, A, and Winchester, Plasma chitotriosidase activity in Gaucher disease patients who have been treated either by bone marrow transplantation or by enzyme replacement therapy with aglucerase, J Inher Metab Dis, (20): 595-602 (1997).
Two 5-10 ml tubes of anticoagulated blood. The preferred anticoagulant is EDTA (lavendar top tubes), ACD (yellow top) tubes are also accepted.
Shipping: Send at room temperature.
Turnaround Time: 7-10 days
CPT Codes: 83891, 83894, 83898, 83912
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Related Tests: Chitotriosidase (Gaucher Disease Biomarker)