CLSI M22-A3 standard, titled "Quality Control for Commercially Prepared Microbiological Culture Media; Approved Standard—Third Edition,"
Accurate culture media performance is the backbone of clinical microbiology. If a culture medium fails to perform correctly, it can lead to false-negative results, delayed diagnoses, and inappropriate patient treatment. What is CLSI M22-A3? clsi m22a3 pdf
: For ongoing QC needs, laboratories should refer to current CLSI standards, such as M100 (Performance Standards for Antimicrobial Susceptibility Testing), which is updated annually. : For ongoing QC needs, laboratories should refer
Exempt media consists of highly stable formulations with a proven track record of minimal failure rates. Laboratories do not need to perform full user QC (such as inoculation with control organisms) on these media if they receive documentation from the manufacturer proving the lot passed QC. Examples of commonly exempt media include: Sheep Blood Agar (SBA) MacConkey Agar (MAC) Examples of commonly exempt media include: Sheep Blood
Upon receiving a shipment of media, log the receipt and inspect the plates or tubes immediately. Check for: Correct labeling and expiration dates. Evidence of freezing, overheating, or drying. Contamination, bubbles, or unequal filling. Step 2: Review Manufacturer Certificates
Hold a training session on the new QC requirements. Emphasize the clinical importance—for example, how a false-negative on Shigella selective agar could delay outbreak detection.
In the highly regulated world of clinical diagnostics and pharmaceutical analysis, precision is not just a goal—it is a legal and ethical requirement. For laboratories performing chromatographic assays, particularly those dealing with therapeutic drug monitoring (TDM), toxicology, and clinical chemistry, the document known as serves as the definitive roadmap.