Mechanisms To Assess Gram Stain Interpretation Proficiency of Technologists at Satellite Laboratories

Abstract

To address Gram stain interpretation proficiency in a satellite/centralized microbiology laboratory paradigm, two programs were devised. In quality assurance program 1, nonmicrobiology technologists at satellite laboratories were required to interpret standardized Gram-stained specimens of clinical material prepared by an experienced microbiologist at a central laboratory. In quality assurance program 2, clinical Gram stains prepared and read by the satellite laboratorians were reviewed by experienced microbiologists at the central laboratory. Satisfactory performance (94%) was achieved in quality assurance program 1. In contrast, quality assurance program 2 had a significantly lower overall performance (89%; P < 0.0001) due to poorer identification of host cells (93%) and bacteria (84%). A variety of intervention mechanisms, including continuous monitoring, resulted in overall performance improvement (P < 0.006). While a technologist challenge has educational merit, having a microbiologist review previously read slides is a better indicator of the technologist's Gram stain interpretation proficiency.

Multicenter Assessment of Gram Stain Error Rates

“…False-negative Gram stains could occur due to inadequate specimen or smear preparation or failure to examine an adequate number of fields. In addition, training and maintenance of proficiency for Gram staining remain challenging (5,20). The consolidation of clinical microbiology laboratories has left many community hospitals with limited laboratory capacity.…”

“…Although the Gram stain has been the staple of clinical microbiology laboratories for over a century, it is still considered a high-complexity procedure by the Clinical Laboratory Improvement Amendments (CLIA) program. The manual nature of the staining process and the subjectivity of Gram stain interpretation contribute to the incidence of errors (4)(5)(6)(7). Inappropriate specimen sampling, specimen processing, smear preparation, and prior antibiotic therapy are all factors that can have an adverse impact on Gram stain result.…”

“…The consolidation of clinical microbiology laboratories has left many community hospitals with limited laboratory capacity. Gram stains are often read by generalists with limited training and proficiency in microbiology, which has an adverse impact on the quality of results (5,7). The lack of reproducibility of Gram stain results, particularly with respiratory specimens, has also led some to question its utility (2,4,21).…”

Targeting errors in microbiology: the case of the Gram stain

“…Over the course of the study, they were able to demonstrate significantly improved performance in reporting of both Gram stain tinctorial characteristics as well as bacterial morphology. While other studies have advocated routine review by the central laboratory of Gram stains performed by the satellite laboratories [11], Guarner et al were able to improve technologist performance to the point where routine review could be limited to once daily. This in turn reduces the burden on core laboratories to monitor performance of the satellites.…”

“…Errors in Gram stain interpretation are more likely to occur at such satellite laboratories and the clinical consequences can be significant [9,10]. While regulatory bodies use proficiency specimens to gauge laboratory performance on Gram stains, these do not adequately measure performance nor do they serve to address gaps in proficiency [10,11].…”