A 2-Year Study of Gram Stain Competency Assessment in 40 Clinical Laboratories

Competency Assessment on Gram Stain Examination and Interpretation Among Medical Laboratory Professionals Working in Selected Hospitals of Addis Ababa, Ethiopia

Background

Laboratory test results are the cornerstone for patient diagnosis and treatment. Gram staining is a classic laboratory test method used to differentiate between bacteria. Competence assessment can help identify gaps and provide suggestions to academics, researchers, and policymakers to address competency gaps. In Ethiopia, there is no evidence of competency assessment by medical laboratory professionals using the Gram-staining technique.

Objective

To assess the competency of medical laboratory professionals on Gram stain examination and interpretation in selected hospitals of Addis Ababa, Ethiopia.

Methods

A cross-sectional study was conducted to assess the competency of medical laboratory professionals on Gram stain examination and interpretation from September 2015 to December 2017.

Results

Of 190 participants, 55 (28.9%) participants scored low knowledge, 131 (68.9%) scored medium knowledge, and only 4 (2.1%) respondents scored high knowledge. From the study variables, education level, supervision by regional or federal government bodies, and training about Gram staining were significantly associated with the knowledge level of study participants. Forty eight (25.3%), 78 (41%), and 64 (33.7%) participants scored low, medium, and high skill level, respectively, from a total of 190 participants. From skill level analysis, hospital type, microscope type, and availability of health information resources were significantly associated with skill levels. There were 44 observations (4%) with major errors and 321 observations (28%) with very major errors from all 1140 observations. Of all observations, 321 (28.2%) reported without grading, 39 observations (3.4%) reported gram-positive bacteria as gram-negative bacteria, and 15 observations (1.4%) reported gram-negative bacteria as gram-positive bacteria.

Conclusion

The current study found that most medical laboratory professionals work without supervision or refresher training in Gram stain examination and interpretation. Hence, medical laboratory professionals' knowledge and skill levels are unsatisfactory. Regular competence assessments, training, and follow-up are necessary to improve the professional competence in medical laboratories.

Performances of automated digital imaging of Gram-stained slides with on-screen reading against manual microscopy

The objective of this study was to evaluate the performances of the automated digital imaging of Gram-stained slides against manual microscopy. Four hundred forty-three identified Gram-stained slides were included in this study. When both methods agreed, we considered the results as correct, and no further examination was carried out. Whenever the methods gave discrepant results, we reviewed the digital images and the glass slides by manual microscopy to avoid incorrectly read smears. The final result was a consensus of multiple independent reader interpretations. Among the 443 slides analyzed in this study, 101 (22.8%) showed discrepant results between the compared methods. The rates of discrepant results according to the specimen types were 5.7% (9/157) for positive blood cultures, 42% (60/142) for respiratory tract specimens, and 22% (32/144) for sterile site specimens. After a subsequent review of the discrepant slides, the final rate of discrepancies dropped to 7.0% (31/443). The overall agreement between the compared methods and the culture results reached 78% (345/443) and 79% (349/443) for manual microscopy and automated digital imaging, respectively. According to culture results, the specificity for automated digital imaging and manual microscopy were 90.8% and 87.7% respectively. In contrast, sensitivity was 84.1% for the two compared methods. The discrepant results were mostly encountered with microorganism morphologies of rare occurrence. The results reported in this study emphasize that on-screen reading is challenging, since the recognition of morphologies on-screen can appear different as compared to routine manual microscopy. Monitoring of Gram stain errors, which is facilitated by automated digital imaging, remains crucial for the quality control of reported Gram stain results.

Harmonization of microbiology processes and standards: work in progress

Clinical microbiology is a highly challenging technical discipline, which makes it difficult to harmonize processes and protocols. In addition, the lack of scientific consensus on some diagnostic algorithms and the need to address the diverse needs of different patient populations contribute to the lack of interlaboratory consistency. Laboratories utilize a number of measures and metrics, but the lack of standardized approaches and data collection means that they cannot effectively evaluate their performance against their peers. Coordinated efforts are required to develop tools that can be used across laboratories regardless of size or complexity.

Improving Gram stain proficiency in hospital and satellite laboratories that do not have microbiology

BACKGROUND

Consolidation of laboratories has left many hospitals and satellite laboratories with minimal microbiologic testing. In many hospitals and satellite laboratories, Gram stains on primary specimens are still performed despite difficultly in maintaining proficiency.

METHODS

To maintain Gram stain proficiency at a community 450-bed hospital with an active emergency room we designed bimonthly challenges that require reporting Gram staining and morphology of different organisms. The challenges consist of five specimens prepared by the reference microbiology laboratory from cultures and primary specimens. Twenty to 23 medical laboratory scientists participate reading the challenges. Results from the challenges are discussed with each medical laboratory scientists. In addition, printed images from the challenges are presented at huddle to add microbiology knowledge.

RESULTS

On the first three challenges, Gram staining was read correctly in 71%-77% of the time while morphology 53%-66%. In the last six challenges correct answers for Gram stain were 77%-99% while morphology 73%-96%.

CONCLUSIONS

We observed statistically significant improvement when reading Gram stains by providing frequent challenges to medical laboratory scientists. The clinical importance of Gram stain results is emphasized during huddle presentations increasing knowledge and motivation to perform the test for patients.

Multicenter Assessment of Gram Stain Error Rates

Gram stains remain the cornerstone of diagnostic testing in the microbiology laboratory for the guidance of empirical treatment prior to availability of culture results. Incorrectly interpreted Gram stains may adversely impact patient care, and yet there are no comprehensive studies that have evaluated the reliability of the technique and there are no established standards for performance. In this study, clinical microbiology laboratories at four major tertiary medical care centers evaluated Gram stain error rates across all nonblood specimen types by using standardized criteria. The study focused on several factors that primarily contribute to errors in the process, including poor specimen quality, smear preparation, and interpretation of the smears. The number of specimens during the evaluation period ranged from 976 to 1,864 specimens per site, and there were a total of 6,115 specimens. Gram stain results were discrepant from culture for 5% of all specimens. Fifty-eight percent of discrepant results were specimens with no organisms reported on Gram stain but significant growth on culture, while 42% of discrepant results had reported organisms on Gram stain that were not recovered in culture. Upon review of available slides, 24% (63/263) of discrepant results were due to reader error, which varied significantly based on site (9% to 45%). The Gram stain error rate also varied between sites, ranging from 0.4% to 2.7%. The data demonstrate a significant variability between laboratories in Gram stain performance and affirm the need for ongoing quality assessment by laboratories. Standardized monitoring of Gram stains is an essential quality control tool for laboratories and is necessary for the establishment of a quality benchmark across laboratories.

Competency assessment of microbiology medical laboratory technologists in Ontario, Canada

Accreditation in Ontario, Canada, requires that licensed clinical laboratories participate in external quality assessment (also known as proficiency testing) and perform competency evaluation of their staff. To assess the extent of ongoing competency assessment practices, the Quality Management Program--Laboratory Services (QMP-LS) Microbiology Committee surveyed all 112 licensed Ontario microbiology laboratories. The questionnaire consisted of a total of 21 questions that included yes/no, multiple-choice, and short-answer formats. Participants were asked to provide information about existing programs, the frequency of testing, what areas are evaluated, and how results are communicated to the staff. Of the 111 responding laboratories, 6 indicated they did not have a formal evaluation program since they perform only limited bacteriology testing. Of the remaining 105 respondents, 87% perform evaluations at least annually or every 2 years, and 61% include any test or task performed, whereas 16% and 10% focus only on problem areas and high-volume complex tasks, respectively. The most common methods of evaluation were review of external quality assessment (EQA) challenges, direct observation, and worksheet review. With the exception of one participant, all communicate results to staff, and most take remedial action to correct the deficiencies. Although most accredited laboratories have a program to assess the ongoing competency of their staff, the methods used are not standardized or consistently applied, indicating that there is room for improvement. The survey successfully highlighted potential areas for improvement and allowed the QMP-LS Microbiology Committee to provide guidance to Ontario laboratories for establishing or improving existing microbiology-specific competency assessment programs.