Molecular diagnostics are essential for detecting intestinal parasites, but evaluating clinical samples from low endemic areas, including Korea, is challenging. We tested the performance of the BD MAX Enteric Parasite Panel in simulated samples for clinical use. Simulated samples were prepared with residual stool samples to confirm the diagnostic performance of the kits. Standard materials for Cryptosporidium parvum, Giardia lamblia, and Entamoeba histolytica were obtained for assessment. Limit of detection was determined by diluting standard materials into multiple concentrations and testing each in duplicate. Repeatability was assessed by retesting all samples twice. Accuracy was evaluated by comparing BD MAX System results with intended results. The limit of detection values obtained using standard materials were 781 cysts/ml, 6,250 oocysts/ml, and 125 DNA copies/ml for G. lamblia, C. parvum, and E. histolytica, respectively. Simulated G. lamblia-positive stool samples with concentrations above 6,250 cysts/ml consistently yielded positive results (100% concordance). However, C. parvum-positive stool samples at 6,250 oocysts/ml showed 50% concordance initially and 75% after retesting. At 62,500 oocysts/ml, the concordance rates were 89% initially and 100% after retesting. Overall agreement was 95.2%, but that for C. parvum was relatively low (82.4%). The diagnostic performances were 87.8% of sensitivity and 100% of specificity. Despite the limited clinical samples, BD MAX Enteric Parasite Panel showed good performance for clinical use, and spiked samples proved useful for evaluating protozoan PCR in low-incidence regions.

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening infection commonly observed in immunocompromised patients, necessitating prompt diagnosis and treatment. This review evaluates the diagnostic performance of various tests used for PJP diagnosis through a comprehensive literature review. Additionally, we propose a diagnostic algorithm tailored to non-human immunodeficiency virus immunocompromised patients, considering the specific characteristics of current medical resources in Korea.

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) represents a devastating and growing global threat, calling for new antibiotic treatments. In Korea, the challenge of treating CRAB is compounded by high nosocomial acquisition rates and limited availability of novel antibiotics. Minocycline, a semisynthetic tetracycline derivative, has been proposed as a therapeutic option for CRAB infections. Nonsusceptibility to minocycline may occur through the efflux pump, TetB. The prevalence of tetB in A. baumannii has increased, along with higher minocycline minimum inhibitory concentrations (MICs). We aimed to evaluate minocycline susceptibility rates in clinical strains of CRAB, and the association between tetB carriage and minocycline susceptibility across different genotypes. Materials and Methods: Representative CRAB blood isolates were collected from Asan Medical Center, Seoul.Minocycline susceptibility was assessed using the Clinical and Laboratory Standards Institute (CLSI) breakpoint (≤4 mg/L) and the proposed pharmacokinetics (PK)/pharmacodynamics (PD) breakpoint (≤1 mg/L). Tigecycline was used as a comparator, and its susceptibility breakpoint for Enterobacterales defined by EUCAST was applied (≤0.5 mg/L).The presence of tetB was detected by PCR, and multilocus sequence typing (MLST) was performed using seven housekeeping genes. Results: Of the 160 CRAB blood isolates, 83.8% were susceptible to minocycline by the CLSI criteria, and 50.6% were PK-PD susceptible by the PK-PD criteria. The minocycline minimum inhibitory concentration (MIC)50 /MIC90 was 1/8 mg/L. tetB was present in 49% of isolates and was associated with a higher minocycline MIC (MIC50/90 2/8 mg/L vs. 1/2 mg/L). No clear correlation was observed between tetB positivity and tigecycline MIC. Nine MLSTs were identified, with significant differences in tetB carriage rates between the major sequence types. Notably, ST191, associated with non-tetB carriage and greater susceptibility to minocycline, declined over the study period (P=0.004), while ST451, associated with tetB carriage, increased. Conclusion tetB was present in 49% of CRAB isolates and was associated with higher MICs and non-susceptibility by both CLSI and PK-PD criteria. However, absence of tetB was not a reliable predictor of minocycline PK-PD susceptibility. Additionally, shifts over time towards genotypes with reduced minocycline susceptibility were observed. Further research is needed to correlate these findings with clinical outcomes and identify additional resistance mechanisms.

We report a case of cytomegalovirus retinitis in a hematopoietic stem cell transplant recipient during valganciclovir pre-emptive therapy followed by maribavir. Analysis of UL97 mutation revealed a C480F substitution associated with high maribavir resistance and low ganciclovir resistance.

Background: The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted global infrastructure. We surveyed laboratories to analyze the changes in testing methods and procedures to improve future pandemic preparedness. Methods: This study surveyed laboratory physicians and technologists in South Korea and analyzed responses from 126 of 323 institutions. The survey was conducted in May 2023 using the proficiency test of the Korean Association of External Quality Assessment Service and examined the diagnostic procedures, personnel, equipment, and quality control. The survey comprised 15 questions covering respondent demographics, public-private proficiency projects, COVID-19 testing procedures, and laboratory status. Results: Of the 126 laboratories, 66.7% performed bacterial smear and culture, 65.9% had biosafety level 2 facilities, and 39.7% had separate nucleic acid extraction areas. Furthermore, 98.4% of the laboratories had biological safety cabinets, the median number of PCR machines was four units, and 77.8% had autoclaves. The median numbers of personnel managing and conducting tests were one and three, respectively. Additionally, 88.1% of the laboratories found the COVID-19 proficiency test helpful, with key benefits in terms of accuracy and skill improvement. COVID-19 tests were primarily used for symptomatic or contact person testing, pre-admission screening, and periodic proactive testing. Specialized testing laboratories conducted up to 50,000 tests daily, and tertiary hospitals conducted up to 1,500 tests.Emergency, pooled, and rapid antigen tests were widely used. Most respondents wanted future tests for respiratory viruses, bacteria, and viral diarrhea, indicating a willingness to participate. Conclusion Aggressive testing and collaboration between health agencies and laboratories are crucial for managing emerging diseases. Systematic preparations are essential to maintain and strengthen laboratory capabilities for future infectious disease outbreaks.

Molecular diagnostics are essential for detecting intestinal parasites, but evaluating clinical samples from low endemic areas, including Korea, is challenging. We tested the performance of the BD MAX Enteric Parasite Panel in simulated samples for clinical use. Simulated samples were prepared with residual stool samples to confirm the diagnostic performance of the kits. Standard materials for Cryptosporidium parvum, Giardia lamblia, and Entamoeba histolytica were obtained for assessment. Limit of detection was determined by diluting standard materials into multiple concentrations and testing each in duplicate. Repeatability was assessed by retesting all samples twice. Accuracy was evaluated by comparing BD MAX System results with intended results. The limit of detection values obtained using standard materials were 781 cysts/ml, 6,250 oocysts/ml, and 125 DNA copies/ml for G. lamblia, C. parvum, and E. histolytica, respectively. Simulated G. lamblia-positive stool samples with concentrations above 6,250 cysts/ml consistently yielded positive results (100% concordance). However, C. parvum-positive stool samples at 6,250 oocysts/ml showed 50% concordance initially and 75% after retesting. At 62,500 oocysts/ml, the concordance rates were 89% initially and 100% after retesting. Overall agreement was 95.2%, but that for C. parvum was relatively low (82.4%). The diagnostic performances were 87.8% of sensitivity and 100% of specificity. Despite the limited clinical samples, BD MAX Enteric Parasite Panel showed good performance for clinical use, and spiked samples proved useful for evaluating protozoan PCR in low-incidence regions.

Molecular diagnostics are essential for detecting intestinal parasites, but evaluating clinical samples from low endemic areas, including Korea, is challenging. We tested the performance of the BD MAX Enteric Parasite Panel in simulated samples for clinical use. Simulated samples were prepared with residual stool samples to confirm the diagnostic performance of the kits. Standard materials for Cryptosporidium parvum, Giardia lamblia, and Entamoeba histolytica were obtained for assessment. Limit of detection was determined by diluting standard materials into multiple concentrations and testing each in duplicate. Repeatability was assessed by retesting all samples twice. Accuracy was evaluated by comparing BD MAX System results with intended results. The limit of detection values obtained using standard materials were 781 cysts/ml, 6,250 oocysts/ml, and 125 DNA copies/ml for G. lamblia, C. parvum, and E. histolytica, respectively. Simulated G. lamblia-positive stool samples with concentrations above 6,250 cysts/ml consistently yielded positive results (100% concordance). However, C. parvum-positive stool samples at 6,250 oocysts/ml showed 50% concordance initially and 75% after retesting. At 62,500 oocysts/ml, the concordance rates were 89% initially and 100% after retesting. Overall agreement was 95.2%, but that for C. parvum was relatively low (82.4%). The diagnostic performances were 87.8% of sensitivity and 100% of specificity. Despite the limited clinical samples, BD MAX Enteric Parasite Panel showed good performance for clinical use, and spiked samples proved useful for evaluating protozoan PCR in low-incidence regions.

Background: The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted global infrastructure. We surveyed laboratories to analyze the changes in testing methods and procedures to improve future pandemic preparedness. Methods: This study surveyed laboratory physicians and technologists in South Korea and analyzed responses from 126 of 323 institutions. The survey was conducted in May 2023 using the proficiency test of the Korean Association of External Quality Assessment Service and examined the diagnostic procedures, personnel, equipment, and quality control. The survey comprised 15 questions covering respondent demographics, public-private proficiency projects, COVID-19 testing procedures, and laboratory status. Results: Of the 126 laboratories, 66.7% performed bacterial smear and culture, 65.9% had biosafety level 2 facilities, and 39.7% had separate nucleic acid extraction areas. Furthermore, 98.4% of the laboratories had biological safety cabinets, the median number of PCR machines was four units, and 77.8% had autoclaves. The median numbers of personnel managing and conducting tests were one and three, respectively. Additionally, 88.1% of the laboratories found the COVID-19 proficiency test helpful, with key benefits in terms of accuracy and skill improvement. COVID-19 tests were primarily used for symptomatic or contact person testing, pre-admission screening, and periodic proactive testing. Specialized testing laboratories conducted up to 50,000 tests daily, and tertiary hospitals conducted up to 1,500 tests.Emergency, pooled, and rapid antigen tests were widely used. Most respondents wanted future tests for respiratory viruses, bacteria, and viral diarrhea, indicating a willingness to participate. Conclusion Aggressive testing and collaboration between health agencies and laboratories are crucial for managing emerging diseases. Systematic preparations are essential to maintain and strengthen laboratory capabilities for future infectious disease outbreaks.

Background: The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted global infrastructure. We surveyed laboratories to analyze the changes in testing methods and procedures to improve future pandemic preparedness. Methods: This study surveyed laboratory physicians and technologists in South Korea and analyzed responses from 126 of 323 institutions. The survey was conducted in May 2023 using the proficiency test of the Korean Association of External Quality Assessment Service and examined the diagnostic procedures, personnel, equipment, and quality control. The survey comprised 15 questions covering respondent demographics, public-private proficiency projects, COVID-19 testing procedures, and laboratory status. Results: Of the 126 laboratories, 66.7% performed bacterial smear and culture, 65.9% had biosafety level 2 facilities, and 39.7% had separate nucleic acid extraction areas. Furthermore, 98.4% of the laboratories had biological safety cabinets, the median number of PCR machines was four units, and 77.8% had autoclaves. The median numbers of personnel managing and conducting tests were one and three, respectively. Additionally, 88.1% of the laboratories found the COVID-19 proficiency test helpful, with key benefits in terms of accuracy and skill improvement. COVID-19 tests were primarily used for symptomatic or contact person testing, pre-admission screening, and periodic proactive testing. Specialized testing laboratories conducted up to 50,000 tests daily, and tertiary hospitals conducted up to 1,500 tests.Emergency, pooled, and rapid antigen tests were widely used. Most respondents wanted future tests for respiratory viruses, bacteria, and viral diarrhea, indicating a willingness to participate. Conclusion Aggressive testing and collaboration between health agencies and laboratories are crucial for managing emerging diseases. Systematic preparations are essential to maintain and strengthen laboratory capabilities for future infectious disease outbreaks.

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening infection commonly observed in immunocompromised patients, necessitating prompt diagnosis and treatment. This review evaluates the diagnostic performance of various tests used for PJP diagnosis through a comprehensive literature review. Additionally, we propose a diagnostic algorithm tailored to non-human immunodeficiency virus immunocompromised patients, considering the specific characteristics of current medical resources in Korea.