Reference ranges for serum S100B protein during the first three years of life

ObjectiveClinical and diagnostic management of traumatic brain injuries is problematic in young children. To facilitate this management, we describe blood reference ranges for the well established biomarker S100B in children younger than 3 years.Design and methodsSerum S100B concentrations were determined by electro-chemiluminescence immunoassay in a population of 186 healthy children aged 0–3 years.ResultsFour age groups emerged, i.e. 0–3, 4–9, 10–24 and 25–36 months. We also found an interesting inverse correlation with head circumference.ConclusionThis study provides useful serum S100B values from the largest cohort of healthy children aged 0–3 years old.     

Reference values for venous and capillary S100B in children

BackgroundThe current management guidelines for pediatric mild head injury (MHI) liberally recommend computed tomography (CT) and frequent admission. Serum protein S100B, currently used in management of adult head injury, has recently shown potential for reducing unnecessary CT scans after pediatric mild head injury. Capillary sampling in children is commonly used when venous sampling fails or is inappropriate. We present reference values for both venous and capillary samples of protein S100B in children.MethodsNeurologically healthy children aged 1–16, scheduled for minor surgery requiring general anesthesia, were prospectively included. Samples for S100B were drawn before (venous) and after (venous and capillary) sedation.ResultsSerum values of 455 children (255 boys, 200 girls) aged 1–14 were computed. S100B was higher in younger children for both venous (r = ? 0.32) and capillary samples (r = ? 0.28). Reference levels for children aged 1 and 2 were significantly higher than for children aged 3–14 years (venous 0.15 μg/L, capillary 0.37 μg/L). For capillary blood, a gender difference was found in the youngest age groups.ConclusionsWe present reference values for venous and capillary S100B in healthy children. These results can be utilized when considering future studies on pediatric head injury and S100B levels.     

Performance of the Pediatric Glasgow Coma Scale in Children with Blunt Head Trauma

Objectives: To compare the accuracy of a pediatric Glasgow Coma Scale (GCS) score in preverbal children with blunt head trauma with the standard GCS score in older children. Methods: The authors prospectively enrolled children younger than 18 years with blunt head trauma. Patients were divided into cohorts of those 2 years and younger and those older than 2 years. The authors assigned a pediatric GCS score to the younger cohort and the standard GCS score to the older cohort. Outcomes were 1) traumatic brain injury (TBI) on computed tomography (CT) scan or 2) TBI in need of acute intervention. The authors created and compared receiver operating characteristic (ROC) curves between the age cohorts for the association of GCS scores and TBI. Results: The authors enrolled 2,043 children, and 327 were 2 years and younger. Among these 327, 15 (7.7%; 95% confidence interval [CI] = 4.4% to 12.4%) of 194 who underwent imaging with CT had TBI visible and nine (2.8%; 95% CI = 1.3% to 5.2%) had TBI needing acute intervention. In children older than 2 years, 83 (7.7%; 95% CI = 6.2% to 9.5%) of the 1,077 who underwent imaging with CT had TBI visible and 96 (5.6%; 95% CI = 4.6% to 6.8%) had TBI needing acute intervention. For the pediatric GCS in children 2 years and younger, the area under the ROC curve was 0.72 (95% CI = 0.56 to 0.87) for TBI on CT scan and 0.97 (95% CI = 0.94 to 1.00) for TBI needing acute intervention. For the standard GCS in older children, the area under the ROC curve was 0.82 (95% CI = 0.76 to 0.87) for TBI on CT scan and 0.87 (95% CI = 0.83 to 0.92) for TBI needing acute intervention. Conclusions: This pediatric GCS for children 2 years and younger compares favorably with the standard GCS in the evaluation of children with blunt head trauma. The pediatric GCS is particularly accurate in evaluating preverbal children with blunt head trauma with regard to the need for acute intervention.     

Pediatric splenic trauma: predicting the success of nonoperative therapy

The charts of all pediatric patients discharged from the Massachusetts General Hospital with a diagnosis of a ruptured spleen were reviewed over a six-year period to determine if any factors could be used to predict which children could be managed safely without operation. Seventy-five percent of these injuries were so managed. The patients who required surgical intervention were older (mean age, 17 years), had multiple injuries (mean ISS, 41), presented with more blood loss (mean hematocrit, 23.5%), and suffered their injuries as a result of a motor vehicle accident. The patients who were successfully managed nonoperatively were younger (mean age, 12 years), had fewer associated injuries (mean ISS, 18), required fewer blood transfusions, and suffered their traumas secondary to falls, sporting events, or altercations. We propose that the injury severity score, the number of units of blood transfused, patient age, as well as the type of trauma suffered be used to predict which patients can be safely managed nonoperatively.     

Home treadmill friction injuries: a five-year review

Treadmills are popular home fitness machines in American homes. Young children are at risk for friction injuries if they contact moving treadmills. The purpose of this study was to determine the impact of treatment of treadmill friction injuries in children. A review of 1,211 pediatric patients younger than 6 years treated at the Intermountain Burn Center between July 1997 and June 2002 was conducted. Forty-eight of these cases (4%) were treadmill friction injuries. The mean TBSA of these burns was 0.5%. The volar surface of the hand was the most common site of injury. Twenty-two (46%) of the 48 identified patients had full-thickness injuries that were treated surgically. Medical costs associated with treadmill friction injuries averaged US 2,385 dollars. The number of treadmill friction accidents resulting in friction injuries to children less than 6 years of age deserves serious attention and increased public awareness.     

Healthcare resource utilization and epidemiology of pediatric burn-associated hospitalizations, United States, 2000.

The objective of this study was to describe the epidemiology and financial burden of burn-associated hospitalizations for children younger than 18 years in the United States. Retrospective data analysis of pediatric burn-associated hospitalizations was done using the Healthcare Cost and Utilization Project Kids' Inpatient Database for 2000. An estimated 10,000 children younger than 18 years were hospitalized for burn-associated injuries in the United States in 2000. These children spent an estimated 66,200 days in the hospital with associated hospital charges equal to USD 211,772,700. Total charges and length of stay for pediatric burn-associated hospitalizations in the United States during 2000 were associated with degree of burn, percentage of total body surface area burned, child's age, region of the United States, hospital location, and hospital type. Children 2 years old or younger were more likely to be nonwhite, be hospitalized for burns, and burn their hands/wrists, compared with children 3 to 17 years of age. Male children in both age groups were more likely to be hospitalized for burns than female children. Children 2 years old or younger were more likely to be burned by hot liquids/vapors and contact with hot substances/objects, while children 3 to 17 years were more likely to be burned by fire/flames. This study is the first national study on healthcare resource utilization for pediatric burn-associated hospitalizations to utilize the KID database. Burns are a major source of pediatric morbidity and are associated with significant national healthcare resource utilization annually. Future burn prevention efforts should emphasize implementing passive injury prevention strategies, especially for young children who are nonwhite and live in low-income communities.     

S-100beta protein-serum levels in healthy children and its association with outcome in pediatric traumatic brain injury

OBJECTIVE: To describe normal serum levels of S-100beta in healthy children and determine whether serum S-100beta levels after traumatic brain injury are associated with outcome. DESIGN: Prospective cohort study. SETTING: Urban, tertiary care, children's teaching hospital. PATIENTS: A total of 136 healthy children and 27 children with traumatic brain injury. METHODS: Serum S-100beta levels were measured in 136 healthy children. A total of 27 children with traumatic brain injury had S-100beta levels collected within 12 hrs of injury. Other indices of severity of injury measured were admission Glasgow Coma Scale score, and Pediatric Risk of Mortality score at 24 hrs (PRISM 24). Outcome was measured by the Pediatric Cerebral Performance Category (PCPC) score at hospital discharge and 6 months postinjury or at death. MEASUREMENTS AND MAIN RESULTS: S-100beta levels in healthy children had a mean of 0.3 microg/L (90% confidence interval, 0.03-1.47) and inversely correlated with age, (r = -.32, p <.001). In children with traumatic brain injury, 6-month postinjury outcome inversely correlated with Glasgow Coma Scale score (r = -.47, p =.01) and correlated with PRISM 24 score (r =.83, p <.001) and S-100beta levels (r =.75, p <.001). Six months postinjury, comparing good outcome (PCPC < or = 3, n = 20) vs. poor outcome (PCPC > or = 4, n = 7), median admission Glasgow Coma Scale scores were 8 (range, 3-15) and 3 (range, 3-7, p =.01), median PRISM 24 scores were 7 (range, 0-19) and 30 (range, 18-35, p <.001), and median S-100beta levels were 0.85 microg/L (range, 0.08-4.8 microg/L) and 3.6 microg/L (range, 1.4-20 microg/L, p <.001), respectively. A serum S-100beta level of > or =2.0 microg/L is associated with poor outcome, with a sensitivity of 86% and a specificity of 95%. The area under the receiver operating curve for S-100beta was 0.94 (+/-0.05). CONCLUSIONS: Serum S-100beta levels in healthy children have a moderate inverse correlation with age. After traumatic brain injury in children, the acute assessment of serum S-100beta levels seems to be associated with outcome.     

A comparison of two different assays for determining S-100B in serum and urine

BACKGROUND: Brain injury after head trauma can be detected by S-100B measurements in serum. Recent preliminary studies indicate that urinary levels of S-100B are also increased after head injury, a finding that is of possible clinical value. The aims of the present study are two-fold: to compare serum measurements of two assays, the Liaison Sangtec 100 system and the Elecsys S100 test, and to investigate to what extent they can detect and measure S-100B in urine. METHODS: A total of 191 serum and 174 urine samples from 107 patients (children aged between 1 and 18 years following head trauma) were measured with both assays. The results were compared using correlation analysis and Bland-Altman difference plots. RESULTS: Serum values of the Sangtec system ranged from 0.02 to 2.28 microg/L, and from 0.005 to 2.13 microg/L for the Elecsys test. Comparisons showed a clear correlation (correlation coefficient 0.80) but not an agreement between the methods. The Sangtec system could only detect S-100B in 20 out of 174 urine samples (range 0.02-0.06 microg/L), whereas the Elecsys test could detect S-100B in 171 samples (range 0.005-0.14 microg/L). No clear relation was observed between the two methods in urine analysis (correlation coefficient 0.60). CONCLUSION: The Sangtec and Elecsys assays are not interchangeable methods when analyzing S-100B in serum or urine samples after head injury.     

S-100蛋白的动态变化对急性出血性脑血管病评价的临床意义

目的：通过观察急性出血性脑血管病患者血浆中S-100蛋白的动态变化，分析其与脑出血相应临床变化之间的关系。方法：应用ELISA法对62例急性出血性脑血管病患者及36例对照的血浆S-100蛋白水平进行动态检测及比较；应用CT测定出血体积并用ICH评分对脑出血进行临床评价。结果：急性出血性脑血管病患者S-100蛋白浓度在发病早期明显升高，1～3d达到峰值，显著高于恢复期及对照组；对于ICH评分较高者S-100蛋白升高更明显，两者呈正相关（P〈0．05）。结论：S-100可作为急性出血性脑血管病损伤早期敏感的检测指标并对患者的预后评价具有重要的临床意义。     

Urinary homogentisic acid in alkaptonuric and healthy children.

To detect and follow-up the metabolic status of patients with alkaptonuria (AKU), urinary homogentisic acid (HGA) was measured by gas chromatography. These results were close to values we obtained by colorimetric method (linearity: upto 700 mg/l, detection limit: 1 mg/l, within-run imprecision (CV): 1.2% at 100 mg/l HGA, 4.9% at 10 mg/l, between-run CV: 6.8% at 100 mg/l). To determine urinary reference ranges of HGA, 84 healthy children (age: 2 months-18 years) were divided into five age groups. HGA and creatinine were measured in their morning urine. Statistical analysis proved that urinary HGA/creatinine ratio is age-dependent. The ratio is relatively high between 1 and 6 years of age, with large scatter (upper limit of reference ranges given as mean + 2 SD: 5.5-7.2 mg/mmol = 0.03-0.04 mmol/mmol creatinine), and it decreases with age. Approximately at the age of 7 years, HGA/creatinine ratio becomes constant, and later it is similar to the adult value (upper limit: 2.8 mg/ mmol = 0.017 mmol/mmol creatinine). We monitored a patient during her 1-5th year of life, and her urinary HGA was 80-200 times higher than the upper limit of the age-matched reference ranges. The measurement of HGA supports the decision for starting restricted protein diet and is useful for the evaluation of the effectiveness of therapy.     

Age-related reference values for serum selenium concentrations in infants and children

BACKGROUND: Children are at particular risk for selenium deficiency, which has potentially serious medical implications. Reliable age-specific reference values for serum selenium concentrations in children are sparse, but are essential for the identification of selenium deficiency and decisions regarding selenium supplementation. METHODS: Using electrothermal atomic absorption spectrometry, we analyzed serum selenium concentrations from 1010 apparently healthy children (age range, 1 day to 18 years) and from 60 patients on a protein-restricted diet because of inborn errors of metabolism. Reference intervals were defined according to recommended guidelines. RESULTS: Medians for serum selenium concentrations showed a statistically significant age dependency: a decrease from the age <1 month (0.64 micromol/L) to 4 months (0.44 micromol/L); an increase to 0.62 micromol/L in the 4-12 months age group; constant values in children between 1 and 5 years of age (0.90 micromol/L); and an additional slight increase to reach a plateau between 5 and 18 years (0.99 micromol/L). Of 43 children older than 1 year and on a protein-restricted diet, 87% showed serum selenium concentrations below the 2.5 percentile. CONCLUSIONS: Because of nutritional changes, serum selenium concentrations are significantly higher in older children than in infants under 1 year of age. The application of age-adjusted reference values may provide more specific criteria for selenium supplementation. Long-term protein restriction in children is reflected by a failure to achieve higher serum selenium concentrations with increasing age.     

Isolated Intraperitoneal Fluid on Abdominal Computed Tomography in Children with Blunt Trauma

OBJECTIVE: To determine the frequency of isolated intraperitoneal fluid (IIF) on abdominal computed tomography (CT) in pediatric blunt trauma patients and the association between IIF and clinically identifiable intra-abdominal injuries (IAIs) in these patients. METHODS: The authors conducted a prospective observational study of consecutive children <16 years old with blunt torso trauma who underwent abdominal CT scanning while in the emergency department (ED). All patients were evaluated by a faculty emergency physician who documented the patient's physical examination. All CTs were interpreted by a single faculty radiologist masked to clinical data. The volume of intraperitoneal fluid was quantified (small, moderate, large) and the presence of organ injury visible on CT was noted. Patients were considered to have IIF if the CT demonstrated intraperitoneal fluid and no solid organ injury. Patients with IIF were followed through their hospitalizations or telephoned in one week if discharged home from the ED. RESULTS: Five hundred twenty-seven children with blunt trauma were enrolled into the study. The mean age (+/-SD) was 7.4 +/- 4.7 years, and the median pediatric trauma score was 10 (range -2 to 12). Eighty-eight patients (17%; 95% CI = 14% to 20%) had intraperitoneal fluid on CT scan and 42 (48%; 95% CI = 37% to 59%) of these patients had IIF. Of the 42 patients with IIF, five patients (all without abdominal tenderness and with a small amount of IIF on CT scan) were discharged to home from the ED and were well at telephone follow-up; the remaining 37 patients were hospitalized. Of the 42 patients with IIF, 7 patients (17%, 95% CI = 7 to 31%) had IAIs subsequently identified (all gastrointestinal injuries) during their evaluations. Six of the seven patients with IIF and subsequently identified IAIs had abdominal tenderness on examination in the ED. The remaining patient had a decreased level of consciousness. CONCLUSIONS: Isolated intraperitoneal fluid occurs in 8% of pediatric blunt trauma patients undergoing abdominal CT, and IAIs are subsequently identified in 17% of these patients. Patients with a small amount of IIF on CT who lack abdominal tenderness and have a normal level of consciousness are at low risk for subsequently identified IAIs.     

Impairment of blood-brain barrier integrity during carotid surgery as assessed by serum S-100B protein concentrations.

During carotid endarterectomy (CEA) the internal carotid artery is cross-clamped for a period of several minutes. This maneuver may cause cerebral hypoperfusion and/or impairment of the blood-brain barrier (BBB) even in cases where clinical signs are absent. The aim of the present study was to examine whether such alterations could be detected by monitoring the cerebral marker S-100B protein concentrations during and after CEA in the serum. Twenty-five consecutive patients (17 M/8 F, mean age: 64.2 years, range 47-79 years) undergoing elective CEA at our department were studied. All of these patients were without perioperative neurological deficit. Intraoperative samples were collected from internal jugular and peripheral venous blood: 1) before carotid cross-clamping; 2) immediately before declamping; 3) after clamp release. Postoperative samples were taken from peripheral blood at 6 and 24 h, respectively. S-100B was assayed in sera using an immunoluminometric technique. During carotid cross-clamping, S-100B protein concentrations in the ipsilateral jugular serum significantly (p < 0.02) increased to pre-clamp values. After declamping, however, S-100B returned to the baseline level. No differences were seen between the responses of hypertensive and normotensive patients. There was no correlation between carotid occlusion time and S-100B protein concentrations. In the peripheral venous serum no significant changes in S-100B concentrations were detected during or after CEA. We presume that the elevation of S-100B protein concentration during CEA in patients with no neurological deficits indicates the transient opening of the BBB elicited by carotid cross-clamping.     

Continuous age-dependent reference ranges for thyroid hormones in neonates, infants, children and adolescents established using the ADVIA Centaur Analyzer.

In neonates, infants, children and adolescents serum concentrations of the thyroid hormones show a clear age dependency. Currently, age-dependent thyroid hormone reference ranges for the new ADVIA Centaur immunoanalyzer are not available. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), total thyroxine (T4), free triiodothyronine (FT3) and total triiodothyronine (T3) were determined in the sera of 460 healthy children aged 0 daysto 18 years from an inland (n=308) and a seaside city (n=152) using the Bayer ADVIA Centaur analyzer. Square root functions defining the upper and lower limit of the continuous age-dependent reference range and the median line for each thyroid hormone were estimated applying a parametric regression technique. Continuous age-dependent reference ranges show a better fit to the obtained data than discontinuous reference ranges. The median TSH and FT4 concentrations decrease within the first year of life and are nearly constant until 18 years of age. The median T4 decreases within the entire age interval, whereas the median FF3 is constant. The median T3 increases within the first year of life and decreases afterwards. The calculated continuous reference ranges for T4, T3 and partly FT4 are consistent with published reference ranges. However, the reference ranges obtained for FT3 and partly TSH differed considerably, compared to published reference ranges. No significant residence- or sex-specific effects on age-adjusted hormone concentrations were found except for a slight residence-specific effect on age-adjusted FT4, which was probably due to assay imprecision. Due to the lack of international standardization, the assay-specific evaluation of reference ranges is very important. Continuous age-dependent reference ranges comply better with the biological reality and are more reliable than discontinuous reference ranges.     

Unique issues in pediatric spinal cord injury

Spinal cord injuries are devastating events, and they are particularly tragic when they affect children or adolescents who have barely had an opportunity to experience life. Of the approximately 10,000 individuals who sustain spinal cord injury each year in the United States, 3% to 5% occur in individuals younger than 15 years of age and approximately 20% occur in those younger than 20 years of age (Nobunaga, Go, & Karunas, 1999). Because of the growth and development inherent in children and adolescents and the unique manifestations and complications associated with spinal cord injuries, management must be developmentally based and directed to the individual's special needs (Vogel, 1997). The many unique facets of pediatric spinal cord injuries are addressed in this article. They clearly delineate the need for care that is responsive to the dynamic changes that occur with growth and development. The multidisciplinary team, combined with a focus on family-centered care, is essential in pediatric spinal cord injuries.     

Long-term outcome of equestrian injuries in children

Purpose: To investigate the possible development of long-term disabilities arising from paediatric equestrian injuries.

Method: All patients, aged 17 years or younger, treated in a hospital setting because of an equestrian injury during a five-year period received a questionnaire. A reference population and healthy friends served as controls.

Results: Four years post-injury, 41 of the 100 respondents still experienced disabilities following the injury. The median Injury Severity Score was 4. Absenteeism from school lasted 2 weeks, and from horse riding, 4 months. Compared to the reference population, the results of the Child Health Questionnaire were poorer considering most of its subscales. In comparison with the friends, the patients only scored lower on 'physical functioning'. The risk factors concerning poor long-term outcomes were being an advanced rider, sustaining injuries other than fractures of the extremities or sustaining subsequent injuries following the riding accident.

Conclusions: Although equestrian injuries in children are minor to moderate in their severity, these injuries are significant considering that a large proportion of patients experience long-term disabilities.     

Age-related changes in plasma coenzyme Q10 concentrations and redox state in apparently healthy children and adults

BACKGROUND: Coenzyme Q10 (CoQ) is an endogenous enzyme cofactor, which may provide protective benefits as an antioxidant. Because age-related CoQ changes and deficiency states have been described, there is a need to establish normal ranges in healthy children. The objectives of this study are to determine if age-related differences in reduced CoQ (ubiquinol), oxidized CoQ (ubiquinone), and CoQ redox state exist in childhood, and to establish reference intervals for these analytes in healthy children. METHODS: Apparently healthy children (n=68) were selected from individuals with no history of current acute illness, medically diagnosed disease, or current medication treatment. Self-reported healthy adults (n=106) were selected from the ongoing Princeton Follow-up Study in greater Cincinnati. Participants were assessed for lipid profiles, ubiquinol concentration, ubiquinone concentration, total CoQ concentration, and CoQ redox ratio. RESULTS: Mean total CoQ and ubiquinol concentrations are similar in younger children (0.2-7.6 years) and adults (29-78 years); however, lipid-adjusted total CoQ concentrations are significantly increased in younger children. Also CoQ redox ratio is significantly increased in younger and older children compared with adults. CONCLUSIONS: Elevated CoQ and redox ratios in children may be an indication of oxidative stress effects, which are associated with early development of coronary heart disease.     

健康成年人和儿童外周血淋巴细胞亚群参考区间的建立

目的建立健康成年人和儿童外周血淋巴细胞亚群百分率参考区间。方法使用荧光抗体,分别对100例不同年龄、性别的健康成年人和100例健康儿童外周血淋巴细胞亚群进行标记,采用美国BD公司的FACSCalibur型流式细胞仪进行检测并分析结果,使用SPSS17.0进行统计学处理。结果 1~5岁健康儿童总调节性T淋巴细胞(总Treg)、天然调节性T淋巴细胞(天然Treg)、诱导调节性T淋巴细胞(诱导Treg)、活化总T淋巴细胞(活化总T)、活化杀伤性T淋巴细胞(活化Ts)、纯真辅助性T淋巴细胞(纯真Th)、记忆辅助性T淋巴细胞(记忆Th)、CD8+CD28+/CD8+、CD4+CD28+/CD4+、B1淋巴细胞(B1)、转化B淋巴细胞(转化B)的95%参考范围分别为(3.41±0.81)%、(1.59±0.48)%、(1.80±0.47)%、(8.05±3.61)%、(13.81±6.86)%、(70.19±6.35)%、(29.90±6.36)%、(76.48±11.45)%、90.90%~100.00%、(10.05±3.76)%、(3.59±1.70)%。对18~65岁健康成年人分别按年龄性别制订了相应的参考范围。结论在相同地域,相同种族,可以建立健康成年人和儿童外周血淋巴细胞亚群的正常参考区间。     

18岁以下健康儿童及青少年网织红细胞计数与分群测定

目的探讨18岁以下健康儿童网织红细胞(RET)计数、分群与性别、年龄的关系,并建立其参考值范围。方法采用Sysmex XE-2100全自动血细胞分析仪对649例广州地区18岁以下健康儿童RET按性别、年龄(婴儿组、幼儿组、学龄前组、学龄组、青春期组)进行计数与分群测定,并对所得数据进行统计学处理;参考范围分别用第2.5百分位数(P2.5)和第97.5百分位数(P97.5)确定。结果 (1)按性别分组,经两个独立样本t检验,RET百分数(RET%)在两性之间有明显差异(P<0.05),男性RET%为1.18%±0.31%,女性为1.24%±0.34%。RET绝对值(RET#)、低荧光强度RET百分率(LFR%)、中荧光强度RET百分率(MFR%)、高荧光强度RET百分率(HFR%)、未成熟RET比率(IRF%)在两性之间差异无统计学意义(P>0.05)。18岁以下健康儿童RET%的范围与性别有关,RET#、IFR%、LFR%、MFR%和HFR%的范围与性别无关。(2)将男女性数据合并进行单因素方差分析,IRF%、MFR%在婴儿组与青春期组间差异有统计学意义(P<0.05)。(3)男女性RET%参考值范围分别为0.64%~1.84%、0.63%~1.96%。结论各实验室应建立与年龄、性别相关的RET参数参考值,对临床疾病的诊断、鉴别诊断、治疗和疗效观察具有更好的应用价值。     

Reference interval for prealbumin for children two to 36 months old

To define a reference value for serum prealbumin (transthyretin) concentration, we used a rate immunonephelometric microassay to quantify it in 76 healthy children, ranging in age from two to 36 months. Age-specific ranges (+/- 2 SD from the mean) are: 2-5.9 months, 142-330 mg/L; 6-11.9 months, 120-274 mg/L; 12-17.9 months, 115-259 mg/L; 18-23.9 months, 143-243 mg/L; 24-36 months, 108-258 mg/L. When the data were grouped into those for subjects younger and older than 12 months of age, the mean for the 2-11.9 month age group (210 mg/L) significantly (P less than 0.01) exceeded that of the 12-36 month age group (187 mg/L). We propose that in spite of a decrease in prealbumin concentration with increasing age, it is acceptable to use the reference interval 116-281 mg/L (+/- 2 SD from the mean) for children from two to 36 months old. We also compared concentrations of prealbumin in serum and plasma of 41 individuals, finding the mean difference to be +11.7 mg/L; concentrations in plasma averaged 6.7% greater than those in serum.