1.Sex-Specific Reference Intervals and AgeRelated Variations in Hematologic Parameters in Korean Adults Measured Using the Beckman Coulter DxH 900 Analyzer
Shinae YU ; Eunkyoung YOU ; Sae Am SONG ; Jeong Nyeo LEE ; Kyung Ran JUN ; Ja Young LEE
Journal of Laboratory Medicine and Quality Assurance 2025;47(1):6-13
Background:
This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults.
Methods:
Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years.
Results:
The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lymphocyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age.
Conclusions
This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.
2.Permanent Congenital Hypothyroidism in Very Low Birth Weight Infants: A Single Center’s Experience
Joo Hyung ROH ; Tae-Gyeong KIM ; Keon Hee SEOL ; Chae Young KIM ; Soo Hyun KIM ; Ji Yoon JEONG ; Ja Hye KIM ; Euiseok JUNG ; Jin-Ho CHOI ; Byong Sop LEE
Neonatal Medicine 2025;32(1):30-38
Purpose:
Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH.
Methods:
This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups.
Results:
Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH.
Conclusion
The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.
3.A practical guide for enteral nutrition from the Korean Society for Parenteral and Enteral Nutrition: Part I. prescribing enteral nutrition orders
Ye Rim CHANG ; Bo-Eun KIM ; In Seok LEE ; Youn Soo CHO ; Sung-Sik HAN ; Eunjung KIM ; Hyunjung KIM ; Jae Hak KIM ; Jeong Wook KIM ; Sung Shin KIM ; Eunhee KONG ; Ja Kyung MIN ; Chi-Min PARK ; Jeongyun PARK ; Seungwan RYU ; Kyung Won SEO ; Jung Mi SONG ; Minji SEOK ; Eun-Mi SEOL ; Jinhee YOON ; Jeong Meen SEO ;
Annals of Clinical Nutrition and Metabolism 2025;17(1):3-8
Purpose:
This study aimed to develop a comprehensive practical guide for enteral nutrition (EN) designed to enhance patient safety and reduce complications in Korea. Under the leadership of the Korean Society for Parenteral and Enteral Nutrition (KSPEN), the initiative sought to standardize EN procedures, improve decision-making, and promote effective multidisciplinary communication.
Methods:
The KSPEN EN committee identified key questions related to EN practices and organized them into seven sections such as prescribing, delivery route selection, formula preparation, administration, and quality management. Twenty-one experts, selected based on their expertise, conducted a thorough literature review to formulate evidence-based recommendations. Drafts underwent peer review both within and across disciplines, with final revisions completed by the KSPEN Guideline Committee. The guide, which will be published in three installments, addresses critical elements of EN therapy and safety protocols.
Results:
The practical guide recommends that EN orders include detailed elements and advocates the use of electronic medical records for communication. Standardized prescription forms and supplementary safety measures are outlined. Review frequency is adjusted according to patient condition—daily for critically ill or unstable patients and as dictated by institutional protocols for stable patients. Evidence indicates that adherence to these protocols reduces mortality, complications, and prescription errors.
Conclusion
The KSPEN practical guide offers a robust framework for the safe delivery of EN tailored to Korea’s healthcare context. It emphasizes standardized protocols and interdisciplinary collaboration to improve nutritional outcomes, patient safety, and operational efficiency. Rigorous implementation and monitoring of adherence are critical for its success.
4.Sex-Specific Reference Intervals and AgeRelated Variations in Hematologic Parameters in Korean Adults Measured Using the Beckman Coulter DxH 900 Analyzer
Shinae YU ; Eunkyoung YOU ; Sae Am SONG ; Jeong Nyeo LEE ; Kyung Ran JUN ; Ja Young LEE
Journal of Laboratory Medicine and Quality Assurance 2025;47(1):6-13
Background:
This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults.
Methods:
Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years.
Results:
The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lymphocyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age.
Conclusions
This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.
5.Permanent Congenital Hypothyroidism in Very Low Birth Weight Infants: A Single Center’s Experience
Joo Hyung ROH ; Tae-Gyeong KIM ; Keon Hee SEOL ; Chae Young KIM ; Soo Hyun KIM ; Ji Yoon JEONG ; Ja Hye KIM ; Euiseok JUNG ; Jin-Ho CHOI ; Byong Sop LEE
Neonatal Medicine 2025;32(1):30-38
Purpose:
Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH.
Methods:
This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups.
Results:
Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH.
Conclusion
The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.
6.Sex-Specific Reference Intervals and AgeRelated Variations in Hematologic Parameters in Korean Adults Measured Using the Beckman Coulter DxH 900 Analyzer
Shinae YU ; Eunkyoung YOU ; Sae Am SONG ; Jeong Nyeo LEE ; Kyung Ran JUN ; Ja Young LEE
Journal of Laboratory Medicine and Quality Assurance 2025;47(1):6-13
Background:
This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults.
Methods:
Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years.
Results:
The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lymphocyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age.
Conclusions
This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.
7.Permanent Congenital Hypothyroidism in Very Low Birth Weight Infants: A Single Center’s Experience
Joo Hyung ROH ; Tae-Gyeong KIM ; Keon Hee SEOL ; Chae Young KIM ; Soo Hyun KIM ; Ji Yoon JEONG ; Ja Hye KIM ; Euiseok JUNG ; Jin-Ho CHOI ; Byong Sop LEE
Neonatal Medicine 2025;32(1):30-38
Purpose:
Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH.
Methods:
This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups.
Results:
Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH.
Conclusion
The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.
8.A practical guide for enteral nutrition from the Korean Society for Parenteral and Enteral Nutrition: Part I. prescribing enteral nutrition orders
Ye Rim CHANG ; Bo-Eun KIM ; In Seok LEE ; Youn Soo CHO ; Sung-Sik HAN ; Eunjung KIM ; Hyunjung KIM ; Jae Hak KIM ; Jeong Wook KIM ; Sung Shin KIM ; Eunhee KONG ; Ja Kyung MIN ; Chi-Min PARK ; Jeongyun PARK ; Seungwan RYU ; Kyung Won SEO ; Jung Mi SONG ; Minji SEOK ; Eun-Mi SEOL ; Jinhee YOON ; Jeong Meen SEO ;
Annals of Clinical Nutrition and Metabolism 2025;17(1):3-8
Purpose:
This study aimed to develop a comprehensive practical guide for enteral nutrition (EN) designed to enhance patient safety and reduce complications in Korea. Under the leadership of the Korean Society for Parenteral and Enteral Nutrition (KSPEN), the initiative sought to standardize EN procedures, improve decision-making, and promote effective multidisciplinary communication.
Methods:
The KSPEN EN committee identified key questions related to EN practices and organized them into seven sections such as prescribing, delivery route selection, formula preparation, administration, and quality management. Twenty-one experts, selected based on their expertise, conducted a thorough literature review to formulate evidence-based recommendations. Drafts underwent peer review both within and across disciplines, with final revisions completed by the KSPEN Guideline Committee. The guide, which will be published in three installments, addresses critical elements of EN therapy and safety protocols.
Results:
The practical guide recommends that EN orders include detailed elements and advocates the use of electronic medical records for communication. Standardized prescription forms and supplementary safety measures are outlined. Review frequency is adjusted according to patient condition—daily for critically ill or unstable patients and as dictated by institutional protocols for stable patients. Evidence indicates that adherence to these protocols reduces mortality, complications, and prescription errors.
Conclusion
The KSPEN practical guide offers a robust framework for the safe delivery of EN tailored to Korea’s healthcare context. It emphasizes standardized protocols and interdisciplinary collaboration to improve nutritional outcomes, patient safety, and operational efficiency. Rigorous implementation and monitoring of adherence are critical for its success.
9.A practical guide for enteral nutrition from the Korean Society for Parenteral and Enteral Nutrition: Part I. prescribing enteral nutrition orders
Ye Rim CHANG ; Bo-Eun KIM ; In Seok LEE ; Youn Soo CHO ; Sung-Sik HAN ; Eunjung KIM ; Hyunjung KIM ; Jae Hak KIM ; Jeong Wook KIM ; Sung Shin KIM ; Eunhee KONG ; Ja Kyung MIN ; Chi-Min PARK ; Jeongyun PARK ; Seungwan RYU ; Kyung Won SEO ; Jung Mi SONG ; Minji SEOK ; Eun-Mi SEOL ; Jinhee YOON ; Jeong Meen SEO ;
Annals of Clinical Nutrition and Metabolism 2025;17(1):3-8
Purpose:
This study aimed to develop a comprehensive practical guide for enteral nutrition (EN) designed to enhance patient safety and reduce complications in Korea. Under the leadership of the Korean Society for Parenteral and Enteral Nutrition (KSPEN), the initiative sought to standardize EN procedures, improve decision-making, and promote effective multidisciplinary communication.
Methods:
The KSPEN EN committee identified key questions related to EN practices and organized them into seven sections such as prescribing, delivery route selection, formula preparation, administration, and quality management. Twenty-one experts, selected based on their expertise, conducted a thorough literature review to formulate evidence-based recommendations. Drafts underwent peer review both within and across disciplines, with final revisions completed by the KSPEN Guideline Committee. The guide, which will be published in three installments, addresses critical elements of EN therapy and safety protocols.
Results:
The practical guide recommends that EN orders include detailed elements and advocates the use of electronic medical records for communication. Standardized prescription forms and supplementary safety measures are outlined. Review frequency is adjusted according to patient condition—daily for critically ill or unstable patients and as dictated by institutional protocols for stable patients. Evidence indicates that adherence to these protocols reduces mortality, complications, and prescription errors.
Conclusion
The KSPEN practical guide offers a robust framework for the safe delivery of EN tailored to Korea’s healthcare context. It emphasizes standardized protocols and interdisciplinary collaboration to improve nutritional outcomes, patient safety, and operational efficiency. Rigorous implementation and monitoring of adherence are critical for its success.
10.Sex-Specific Reference Intervals and AgeRelated Variations in Hematologic Parameters in Korean Adults Measured Using the Beckman Coulter DxH 900 Analyzer
Shinae YU ; Eunkyoung YOU ; Sae Am SONG ; Jeong Nyeo LEE ; Kyung Ran JUN ; Ja Young LEE
Journal of Laboratory Medicine and Quality Assurance 2025;47(1):6-13
Background:
This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults.
Methods:
Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years.
Results:
The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lymphocyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age.
Conclusions
This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.

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