[Code of Federal Regulations] [Title 21, Volume 8] [Revised as of April 1, 2008] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR866.1645] [Page 255] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 866_IMMUNOLOGY AND MICROBIOLOGY DEVICES--Table of Contents Subpart B_Diagnostic Devices Sec. 866.1645 Fully automated short-term incubation cycle antimicrobial susceptibility system. (a) Identification. A fully automated short-term incubation cycle antimicrobial susceptibility system is a device that incorporates concentrations of antimicrobial agents into a system for the purpose of determining in vitro susceptibility of bacterial pathogens isolated from clinical specimens. Test results obtained from short-term (less than 16 hours) incubation are used to determine the antimicrobial agent of choice to treat bacterial diseases. (b) Classification. Class II (special controls). The special control for this device is FDA's guidance document entitled ``Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA.'' [68 FR 5827, Feb. 5, 2003]