Establishment of reference intervals for complete blood count parameters in venous blood for children in the Xiamen area, China

Sex- and age-based reference intervals for capillary complete blood count parameters among urban preschoolers in southeast China based on a large community population

Background and aim

Pediatricians commonly use the complete blood count (CBC) of capillary blood to evaluate health status, guide diagnoses, and determine treatment strategies. This study aimed to establish sex- and age-specific reference intervals (RIs) for 23 capillary CBC parameters for urban preschoolers in Fuzhou, Southeast China.

Materials and methods

Capillary blood CBC data of 18,369 healthy preschoolers who underwent annual physical examinations at Fujian Maternity and Child Health Hospital between January 01, 2022, and November 31, 2023, were analyzed retrospectively. To fully validate the new RIs, the data of all apparently healthy children within the same age cohort at the same institution were comprehensively analyzed in December 2023. The new RIs were assessed by comparing them with the RIs currently used in laboratories and those obtained from different regions, sample types, or methodologies.

Results

Dynamic temporal changes that differ between males and females were observed in the blood system of 3-7-year-old children in this region. The new sex- and age-specific RIs for capillary CBC parameters were feasible to guide clinical decision-making in the local region.

Conclusions

Our findings demonstrated the importance of establishing sex- and age-specific RIs for each region and underscored the necessity of continuous adjustment of clinical Rls based on statistical rules and clinical responses.

Establishment and validation of haematological reference intervals for newborns aged 5 to 28 days in Nanjing, China

BACKGROUND

China lacks a standard for reference intervals (RIs) of complete blood cell (CBC) counts in newborns. This study aimed to determine local haematological RIs for newborns.

METHODS

This prospective study was conducted from January 2020 to December 2020 in Nanjing Maternity and Child Health Care Hospital. We collected capillary blood specimens from 497 healthy newborns aged 5-28 days. We calculated the RIs as nonparametric 2.5th to 97.5th percentiles and 90% confidence intervals following the EP28-A3c guideline. We validated the RIs in another 20 specimens from healthy newborns.

RESULTS

The RIs for the 18 CBC parameters were: white blood cell count 7.17-15.69 × 109/L; monocytes# 0.52-1.66 × 109/L; Mono% 5.7-14.1; eosinophils# 0.16-1.08 × 109/L; Eos% 1.5-8.9; Lymphocytes# 4.04-8.08 × 109/L; Lymph% 40.1-67.8; Neutrophils# 1.59-6.41 × 109/L; Neut% 18.1-46.7; Basophils# 0.00-0.04 × 109/L; Baso% 0.0-0.4; red blood cell count 3.38-5.89 × 1012/L; haemoglobin (Hb) 116-198 g/L; Hematocrit % 35.2-61.2; mean corpuscular Hb (MCH) 30.9-36.3 pg/L; MCH concentration 310-341 g/L; mean corpuscular volume 94.5-112.2 fL; and platelets 210-610 × 109/L. The RIs had a conformity rate of 90%-100% in the validation specimens.

CONCLUSION

We established region-specific RIs for CBC parameters in healthy newborns to help diagnose haematological disease in neonates.

Eosinophil-derived neurotoxin levels in early childhood and association with preschool asthma - A prospective observational study

INTRODUCTION

Eosinophil-derived neurotoxin (EDN) is related to childhood asthma, while normal values are lacking. We aimed to document serum EDN levels at 1 and 3 years in general and in non-atopic children, and explore if EDN levels differed by sex or were associated with preschool asthma at 3 years.

METHODS

From the PreventADALL birth cohort, we included 1233 children with EDN analysed using ImmunoCAP at 1 and/or 3 years. Non-atopic children had no history of wheeze, asthma, allergic sensitization or atopic dermatitis. Preschool asthma was defined as having ≥3 episodes of bronchial obstruction between 2 and 3 years, plus doctor diagnosed asthma and/or asthma medication use by 3 years. The upper limit of normal (ULN) of EDN was defined as the 95th percentile. With Youden Index we calculated EDN cut-off levels for risk of preschool asthma.

RESULTS

The overall median (ULN) EDN levels were 27.4 (121) μg/L at 1 year (n = 787), and 20.1 (87.8) μg/L at 3 years (n = 857). Non-atopic children had EDN levels of 24.0 (107) μg/L at 1 year (n = 147), and 17.3 (84.6) μg/L at 3 years (n = 173). EDN levels were higher in boys compared to girls; 32.0 (133) versus 24.5 (97.0) μg/L at 1 year, and 20.9 (96.3) versus 19.0 (72.4) μg/L at 3 years. Preschool asthma was observed in 109/892 (12.2%) children. Higher EDN levels at 1 (>26.7 μg/L) and 3 (≥20.5 μg/L) years were associated with preschool asthma; adjusted OR (95% CI) 2.20 (1.09, 4.41) and 4.68 (2.29, 9.55), respectively.

CONCLUSION AND CLINICAL RELEVANCE

We report EDN values in early childhood, demonstrating higher levels at 1 compared to 3 years and in boys compared to girls at both ages. Higher EDN levels at both ages were associated with preschool asthma. However, EDN cut-off levels for preschool asthma were overall lower than the ULN of non-atopic children, limiting translation into clinical practice.

Age- and sex-specific reference intervals for complete blood count parameters in capillary blood for Chinese neonates and infants: A prospective study

BACKGROUND

The reference intervals (RIs) of laboratory tests are essential for disease diagnosis, therapy monitoring, and health assessment. They are also significant for clinicians to discriminate between subjects with disease and healthy subjects. However, RIs for complete blood count (CBC) parameters in capillary blood for children are deficient. This study aimed to establish capillary blood RIs for blood cell parameters in neonates and infants from birth to 2 years of age in Zhengzhou.

METHODS

We prospectively collected a total of 1840 capillary blood specimens from healthy subjects from birth to 2 years of age. Hematology RIs were established by analyzing capillary blood sample data, and RIs and 90 % confidence intervals (CIs) were calculated according to Clinical and Laboratory Standards Institute (CLSI) C28-A3 guidelines.

RESULTS

RIs were established for hematological parameters of capillary blood in neonates and infants from birth to 2 years of age. The levels of almost all hematological parameters, except for the lymphocyte (LYMPH), platelet (PLT), and thrombocytocrit (PCT) parameters, peaked in the first month after birth and then decreased to lower levels within 6 months. There were significant sex differences in most erythrocyte-related parameters, with higher levels in males than in females. Erythrocyte-related parameters showed an increasing tendency with increasing age after the second month. Neutrophil (NEUT) levels were high on the third day of life, declined to a nadir in the first month, and then slowly increased with age. LYMPH levels were low at birth and began to increase after birth, peaked at approximately-six months of age and then gradually declined with age. PLT and PCT levels showed an increasing trend during the first month, while the other parameters showed a decreasing trend. All platelet-related and leukocyte-related parameters showed no significant difference with sex.

CONCLUSION

We provide comprehensive age- and sex-specific RIs, including RIs for neonates in Henan. Our study provides more comprehensive reference ranges for Child Health Hospital and children's medical institutions, which may facilitate preliminary screening, diagnosis, and therapy.

Establishing Reference Values for Peripheral Blood Lymphocyte Subsets of Healthy Children in China Using a Single Platform

Lymphocyte subsets significantly change during childhood; thus, age-matched reference values derived from healthy children are crucial. We established reference values for lymphocyte subsets, including T cells (CD3+), CD4 T cells (CD3 + CD4+), CD8 T cells (CD3 + CD8+), double negative T (DNT) cells (CD3 + CD4-CD8-), B cells (CD3-CD19+), NK cells (CD3-CD56+), and NKT-like cells (CD3 + CD56+) in the peripheral blood of 813 healthy children. We used the method of the international standard document (Clinical Laboratory Standard Institute C28-A3) to establish reference intervals with a single platform. First, we used the Skewness and Kurtosis test to analyze the normality of the data. The nonnormally distributed data was transformed into approximately normal distribution by the Box-Cox transformation. Second, we used the Tukey's method to eliminate outliers. Further, all the subjects were grouped into subgroups according to sex (male and female) and age (0–1 month, 2–12 months, 1–3 years, 4–6 years, and 7–18 years). We used the standard normal deviation test (Z-test) to evaluate whether age and sex were possible grouping factors. The analyses indicated age to be an important factor associated with changes in lymphocyte subsets. The absolute number of lymphocyte subsets and total number of lymphocytes, T cells, CD4 T cells, CD8 T cells, and B cells gradually increase from birth to 12 months and then gradually decrease with age. Furthermore, CD4 T cells and the ratio of CD4⁺/CD8⁺ gradually decrease with age. In contrast, CD8 T and DNT cells gradually increase with age. The percentage and number of NK and NKT-like cells gradually increase with age and remain stable between 1 and 18 years of age. In conclusion, the age-related reference intervals established in healthy children in this study can aid in monitoring and assessing the changes in immune levels in diseased conditions.

Age and sex specific reference intervals of 13 hematological analytes in Chinese children and adolescents aged from 28 days up to 20 years: the PRINCE study

OBJECTIVES

Pediatric Reference Intervals in China (PRINCE) is a nationwide initiative that aims to establish and validate harmonized reference intervals (RIs) for Chinese children and adolescents, in which 15,150 healthy volunteers aged up to 20 years were recruited from 11 centers to establish RIs and 7,557 children and adolescents were enrolled from 21 centers to validate RIs.

METHODS

The complete blood cell counts (CBC) of venous whole blood were measured by hematology analyzers through Sysmex systems in different centers. Age- and sex-specific RIs were calculated according to the guidelines.

RESULTS

Unlike adults with certain levels of analyte concentrations, hematological parameters of children changed through growth and development. Red blood cell counts, hemoglobin, and hematocrit increased with age, and revealed higher concentrations in boys than girls after puberty. White blood cell counts and platelet counts showed significant higher levels than adults before 2 years of age, and then gradually decreased without distinct sex differences. In addition, lymphocyte counts decreased with age while neutrophil counts showed an opposite trend. The lower and upper limits of pediatric RIs of CBC were different from those of adults.

CONCLUSIONS

The validation of RIs indicated that the PRINCE study provided a version of RIs suitable for most of regions in China. This first harmonized pediatric RIs of CBC across China provided a robust database to understand the dynamic changes of hematologic parameters from birth to adolescence, and will contribute to clinical diagnosis and prognosis evaluation for pediatric patients as well.

Establishment of pediatric reference intervals for complete blood count parameters in capillary blood in Beijing

BACKGROUND

Reference intervals (RIs) are normal ranges of clinical indicators established from healthy subjects, and comparing test results with RIs is the first step for clinicians in differentiating between healthy and diseased subjects. Capillary blood is widely used in complete blood count (CBC) tests in children; however, capillary blood-based RIs for the CBC parameters are still lacking for all pediatric populations. The aim of this study was to establish capillary blood-based RIs for the CBC parameters in children aged 3 months to 18 years in Beijing.

METHODS

A total of 6799 capillary blood specimens from children were collected, including 3832 males and 2967 females aged 3 months to 18 years, and CBC parameters were analyzed. Data analysis, RI calculations, and 90% confidence interval (CI) calculations were performed according to CLSI C28-A3 guidelines.

RESULTS

Capillary blood RIs for 22 CBC parameters were established in children aged 3 months to 18 years. The levels of most red blood cell-related parameters increased with age and were generally higher in males than in females. White blood cell counts were relatively stable, with no obvious upward or downward trends from 3 months to 18 years of age. Platelet levels decreased within the first year and tended to be stable thereafter. Further validation with 458 healthy children illustrated that the verified results were within the established RIs with a 90%-100% proportion.

CONCLUSION

We established capillary blood RIs for 22 CBC parameters in children across a broad age range in Beijing.

A retrospective cohort study on red blood cell morphology changes in pre-school age children under nitrous oxide anesthesia

Background

Megaloblastic anemia or bone marrow changes could occur after prolonged nitrous oxide inhalation via vitamin B₁₂ inactivation related DNA synthesis impairment. Previous researches have studied hematological changes with nitrous oxide exposure, but only in adults or adolescents. Pre-school age children with active hematopoietic red bone marrow are more vulnerable to potential side effects of nitrous oxide and might experience growth impairment. The purpose of our study was to analyze red blood cell morphology changes under nitrous oxide anesthesia in pre-school age children.

Methods

One hundred thirty-six children under 5 years old scheduled for hemivertebra resection were analyzed. According to fresh gas type in anesthesia records, 71 children who received nitrous oxide in oxygen during anesthesia maintenance were categorized into the nitrous oxide group and the other 65 who received air in oxygen were the air group. Complete blood counts in perioperative period were assessed for anemia, macrocytosis, microcytosis, anisocytosis, hyperchromatosis and hypochromatosis. The peak value and change percentage were calculated for mean corpuscular volume and red cell distribution width.

Results

Forty-two children in the air group (64.6%) and 30 in the nitrous oxide group (42.3%) developed anemia (P = 0.009). None developed macrocytosis in both groups. Postoperative mean corpuscular volume peaked (mean [95% confidence interval]) at 83.7(82.9–84.4) fL, and 83.2(82.4–83.9) fL and postoperative red cell distribution width at 13.8% (13.4–14.2%), and 13.9% (13.6–14.2%) for the air group and the nitrous oxide group. Both the relative change of mean corpuscular volume (P = 0.810) and red cell distribution width (P = 0.456) were similar between the two groups.

Conclusions

No megaloblastic red blood cell changes were observed with nitrous oxide exposure for 4 h in pre-school age children undergoing hemivertebra resection.

Age-dependent changes of total and differential white blood cell counts in children

BACKGROUND

Total and differential white blood cell counts are important for the diagnostic evaluation of suspected diseases. To facilitate the interpretation of total and differential white blood cell counts in pediatric patients, the present study investigated age-dependent changes in total and differential white blood cell counts in healthy reference children.

METHODS

Data were obtained from the Pediatric Reference Intervals in China study (PRINCE), which aims to establish and verify pediatric reference intervals for Chinese children based on a nationwide multicenter cross-sectional study from January 2017 to December 2018. Quantile curves were calculated using the generalized additive models for location, shape, and scale method. The 2.5th, 50th, and 97.5th quantile curves were calculated for both total and differential white blood counts. Percents of stacked area charts were used to demonstrate the proportions of differential white blood cells. All statistical analyses were performed using R software.

RESULTS

Both 50th and 97.5th quantiles of total white blood cell count and monocyte count were highest at birth, then rapidly decreased in the first 6 months of life; relatively slow reduction continued until 2 years of age. The lymphocyte count was low during infancy and increased to its highest level at 6 months of age; it then exhibited moderate and continuous reduction until approximately 9 years of age. The pattern of neutrophil count changed with age in a manner opposite to that of lymphocyte count. Besides, there were two inter-sections of lymphocyte count and neutrophil count during infancy and at approximately 5 years of age, based on locally weighted regression (LOESS) analysis. There were no apparent age-related changes in eosinophil or basophil counts.

CONCLUSION

These data regarding age-related changes in total and differential white blood cell counts can be used to assess the health of pediatric patients and guide clinical decisions.

Haematological and Biochemical Reference Values for Healthy Population of Maferinyah Rural Community in Guinea

Guinea's reference ranges for biological parameters rely on those of Caucasian values. Variability in reference ranges according to the context is well-documented. We conducted this study for the purpose of future malaria clinical trials that assess the efficacy and safety of malaria drugs. A repeated cross-sectional study was carried out, in an apparently healthy cohort population. Surveys took place in Maferinyah rural community, which is located at 75 km from the capital. The 2.5^th and 97.5^th percentiles were determined nonparametrically and stood for reference intervals. Reference values were determined separately for males and females according to ranges of age (6-10 years of age; 11-15 years of age; 16-45 years of age). Differences between genders were tested using the Mann-Whitney test, while the Friedman test was performed to test differences within each gender group according to the seasons. A total of 450 volunteers were enrolled. The median age was 13. Males 16-45 years of age had significantly higher hematologic and biochemical values compared to a female of the same age (for hematological parameters: Mean Cell Hemoglobin Concentration MCHC p ≤ 0.001, Platelets p ≤ 0.001, monocytes p = 0.0305, eosinophils p = 0.0225; for biochemical parameters: Aspartate aminotransferase AST p ≤ 0.001, Alanine Aminotransferase ALT p ≤ 0.001, creatinine p ≤ 0.001). We noticed significant seasonal variations for all the biochemical parameters and some hematologic parameters (Mean Corpuscular Hemoglobin MCH, MCHC, Mean Cell volume). This is the first study establishing hematologic and biochemical parameters in Guinea. These findings provide a useful guide for the clinical researchers and care providers. Studies on large scale and in different settings would be also desirable.

Establishing reference intervals of coagulation indices based on the ACL Top 700 system for children in Southwestern Fujian, China

BACKGROUND

Till date, China has not issued industry standards for reference intervals (RIs) of pediatric blood coagulation indices. Here, we evaluated changes in the coagulation indices in the venous blood of healthy children aged 29 days to 12 years derived using the ACL Top 700 system and established appropriate RIs.

METHODS

We analyzed venous blood from 1770 healthy children for five coagulation indices. RIs were established according to the Clinical and Laboratory Standards Institute C28-A3c guideline.

RESULTS

The coagulation indices were grouped by age. For prothrombin time (PT) and international normalization ratio (INR), the RIs of infants and toddlers were identical; preschool children had the same RI as school-age children. Pediatric RIs for PT and INR were slightly lower than those for adults. The RIs of activated partial thromboplastin time (APTT), thrombin time (TT), and fibrinogen (FIB) in childhood were divided into two groups by age (1 month to 1 year and 1-12 years). The RI of APTT in infants was the widest; the overall level of FIB in infants was the lowest; children's APTT and FIB RIs were lower than those of adults. The pattern of TT values and RI trends in childhood were similar to those of APTT.

CONCLUSIONS

There were minor changes in the RIs of coagulation indices for children. The RIs of PT, INR, APTT, TT, and FIB must be grouped by age. The RIs of coagulation indices for children were different from those for adults; therefore, establishing separate RIs for children is necessary.