Quality Control
Quality control (QC) must be performed following all applicable local, state, and/or federal regulations. Your laboratory's QC procedures will be written based on these regulations and the accreditation requirements that apply.
At a minimum, the intended reactivity of the Gram stain must be verified with every new batch of stain and at least weekly against known gram-positive and gram-negative control organisms.1 However, individual laboratories may have more stringent requirements. No matter what the required frequency for QC testing - if you prepare and read Gram stains infrequently, it is helpful to stain QC slides at the same time as a patient Gram stain smear.
