Background: The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings. Methods: We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes. Results: A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%). Conclusion This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.

Background: The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings. Methods: We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes. Results: A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%). Conclusion This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.

Background: The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings. Methods: We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes. Results: A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%). Conclusion This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.

Background: The accuracy of Logical Observation Identifiers Names and Codes (LOINC) mappings is reportedly low, and the LOINC codes used for research purposes in Korea have not been validated for accuracy or usability. Our study aimed to evaluate the discrepancies and similarities in interoperability using existing LOINC mappings in actual patient care settings. Methods: We collected data on local test codes and their corresponding LOINC mappings from seven university hospitals. Our analysis focused on laboratory tests that are frequently requested, excluding clinical microbiology and molecular tests. Codes from nationwide proficiency tests served as intermediary benchmarks for comparison. A research team, comprising clinical pathologists and terminology experts, utilized the LOINC manual to reach a consensus on determining the most suitable LOINC codes. Results: A total of 235 LOINC codes were designated as optimal codes for 162 frequent tests.Among these, 51 test items, including 34 urine tests, required multiple optimal LOINC codes, primarily due to unnoted properties such as whether the test was quantitative or qualitative, or differences in measurement units. We analyzed 962 LOINC codes linked to 162 tests across seven institutions, discovering that 792 (82.3%) of these codes were consistent. Inconsistencies were most common in the analyte component (38 inconsistencies, 33.3%), followed by the method (33 inconsistencies, 28.9%), and properties (13 inconsistencies, 11.4%). Conclusion This study reveals a significant inconsistency rate of over 15% in LOINC mappings utilized for research purposes in university hospitals, underlining the necessity for expert verification to enhance interoperability in real patient care.

We retrospectively examined current trends in ordering for erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) testing. All claims corresponding to ESR and CRP testing for hospital visits in 2022 were obtained from a platform operated by the Health Insurance and Review Agency. The annual (2018–2022) utilization and cost of ESR and CRP, total inpatient days, and patient encounters with outpatients were retrieved. The number of ESR and CRP tests gradually increased over 5 years, except a slight decrease in 2020. The proportion of claims with co-ordering of ESR and CRP tests was 46.64%. More than 60% co-ordering claims were observed in orthopedic surgery, neurosurgery, and plastic surgery departments. The proportion of co-orders was relatively high in inpatient setting and primary hospitals. This study indicated frequent co-ordering patterns of ESR and CRP tests, highlighting an urgent need for diagnostic stewardship programs on ESR and CRP testing in Korea.

We retrospectively examined current trends in ordering for erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) testing. All claims corresponding to ESR and CRP testing for hospital visits in 2022 were obtained from a platform operated by the Health Insurance and Review Agency. The annual (2018–2022) utilization and cost of ESR and CRP, total inpatient days, and patient encounters with outpatients were retrieved. The number of ESR and CRP tests gradually increased over 5 years, except a slight decrease in 2020. The proportion of claims with co-ordering of ESR and CRP tests was 46.64%. More than 60% co-ordering claims were observed in orthopedic surgery, neurosurgery, and plastic surgery departments. The proportion of co-orders was relatively high in inpatient setting and primary hospitals. This study indicated frequent co-ordering patterns of ESR and CRP tests, highlighting an urgent need for diagnostic stewardship programs on ESR and CRP testing in Korea.

We retrospectively examined current trends in ordering for erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) testing. All claims corresponding to ESR and CRP testing for hospital visits in 2022 were obtained from a platform operated by the Health Insurance and Review Agency. The annual (2018–2022) utilization and cost of ESR and CRP, total inpatient days, and patient encounters with outpatients were retrieved. The number of ESR and CRP tests gradually increased over 5 years, except a slight decrease in 2020. The proportion of claims with co-ordering of ESR and CRP tests was 46.64%. More than 60% co-ordering claims were observed in orthopedic surgery, neurosurgery, and plastic surgery departments. The proportion of co-orders was relatively high in inpatient setting and primary hospitals. This study indicated frequent co-ordering patterns of ESR and CRP tests, highlighting an urgent need for diagnostic stewardship programs on ESR and CRP testing in Korea.

We retrospectively examined current trends in ordering for erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) testing. All claims corresponding to ESR and CRP testing for hospital visits in 2022 were obtained from a platform operated by the Health Insurance and Review Agency. The annual (2018–2022) utilization and cost of ESR and CRP, total inpatient days, and patient encounters with outpatients were retrieved. The number of ESR and CRP tests gradually increased over 5 years, except a slight decrease in 2020. The proportion of claims with co-ordering of ESR and CRP tests was 46.64%. More than 60% co-ordering claims were observed in orthopedic surgery, neurosurgery, and plastic surgery departments. The proportion of co-orders was relatively high in inpatient setting and primary hospitals. This study indicated frequent co-ordering patterns of ESR and CRP tests, highlighting an urgent need for diagnostic stewardship programs on ESR and CRP testing in Korea.

A 30-year-old Korean man with myelodysplastic syndrome admitted hospital due to undifferentiated fever and recurrent skin lesions. He received combination therapy with high doses of meropenem, tigecycline and amikacin, yielding carbapenem resistant Klebsiella pneumoniae (CRKP) harboring K. pneumoniae carbapenemase (KPC)-2 from blood cultures on hospital day (HD) 23. Ceftazidime/avibactam was started at HD 37 and CRKP was eradicated from blood cultures after 5 days. However, ceftazidime/avibactam-resistant CRKP carrying KPC-44 emerged after 26 days of ceftazidime/avibactam treatment and then ceftazidime/ avibactam-resistant, carbapenem-susceptible K. pneumoniae carrying KPC-135 was isolated on HD 65. The 3-D homology of KPC protein showed that hot spot changes in the omega loop could be attributed to ceftazidime/avibactam resistance and loss of carbapenem resistance.Whole genome sequencing of serial isolates supported that phenotypic variation was due to clonal evolution than clonal replacement. The treatment regimen was changed from CAZ/AVI to meropenem-based therapy (meropenem 1 g iv q 8 hours and amikacin 600 mg iv per day) starting with HD 72. CAZ/AVI-susceptible CRKP was presented again from blood cultures on HD 84, and the patient expired on HD 85. This is the first Korean report on the acquisition of ceftazidime/avibactam resistance through the emergence of blaKPC variants.

Background: Neutralization testing to confirm hepatitis B surface antigen (HBsAg) positivity is strongly recommended to avoid false-positive results but was not reimbursed in Korea at that time of the study. This study aimed to investigate the status of neutralization testing for the confirmation of an HBsAg test result in Korea. Methods: The manufacturers of HBsAg qualitative reagents were listed based on the proficiency test report of the Korean Association of External Quality Assessment Service. The supply status of neutralization reagents and their user laboratories were investigated. The laboratories using neutralization reagents were surveyed to determine the number of specimens utilized for HBsAg qualitative testing and subsequent neutralization testing. Their results were categorized according to the HBsAg levels measured in 2022. Results: Seventeen laboratories performed HBsAg neutralization testing using Roche (14 sites) and Abbott (3 sites) reagents. Each laboratory applied a neutralizing agent to some HBsAg-positive samples using different cutoff points based on the instrument’s measurement values. In 14 laboratories using Roche neutralization reagents, 53.6% of the specimens were positive for HBsAg on neutralization test, of which 94.1% had a cutoff index of <10. Conclusions HBsAg neutralization testing is crucial for preventing falsepositive results of HBsAg qualitative tests, especially for specimens with lower measurement values.