Section 866.5760 - Tryptase test system(a)Identification. A tryptase test system is a device that aids in the diagnosis of systemic mastocytosis. It is intended for in vitro diagnostic use as an aid in the clinical diagnosis of patients with a suspicion of systemic mastocytosis in conjunction with other clinical and laboratory findings.(b)Classification. Class II (special controls). The special control is FDA's guideline entitled "Class II Special Controls Guideline: Tryptase Test System as an Aid in the Diagnosis of Systemic Mastocytosis." For availability of the document, see § 866.1(e) . 79 FR 56010 , Sept. 18, 2014