Evaluation of five formulae for estimating body surface area of nigerian children

The Z-scores of cardiac indices among healthy children: a systematic review and meta-analysis

BACKGROUND

The application of z-scores in normalizing the cardiac size function and structural dimension will be of immense benefit to the clinician, especially in evaluating children with cardiac anomalies. However, heterogeneity in the obtained z- score results is high, thus a subgroup analysis by region (or continent) to assist healthcare practitioners is necessary.

OBJECTIVES

The review aimed to ascertain the overall mean z-scores for cardiac structures and function.

METHODS

A thorough search of several databases, EMBASE, PubMed/MEDLINE, and Google Scholar was made. Articles published between January 1999 and December 2023 were recruited, of which the last search was done in December 2023. Keywords used in the search were "z-scores", Children; echocardiography; cardiac structures; cardiac function; and body surface area (BSA)". We restricted our search to children. Besides, additional relevant articles were manually searched. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) was used to highlight selected studies using a pre-defined search protocol. The I2 statistics were used to ascertain statistical heterogeneity.

RESULTS

Two hundred and forty citations were identified in our search strategy, of which a total of 34 studies were identified. Twenty-four were excluded from the thirty-four studies. A total of 11 studies met our inclusion criteria shown in the PRISMA. Apart from different z scores reading obtained from various countries and regions, some authors focused on few cardiac parameters while others were exhaustive. The mean z-scores of the cardiac structures from various countries/regions range as follows; The range of Z scores obtained by different studies and regions above are as follows; MV;-1.62-0.7 AV: -1.8 -0.5 TV: -2.71 -0.7; PV ; -1.52- (-0.99) MPA; -1-81 -0.8 LPA;-1.07-0.4; RPA;-0.92- 0.1 IVSD; -0.1.77-1.89 LVPWD; -0.12-1.5 LVPWS; -0.1-0.15 LVPWS; 0.03-0.18 LVIDD; -1.13- (-0.98) LVIDS; -0.84-10.3 respectively. The mean z-score from the pooled studies showed mitral valve diameter as -0.24 ± 0.9 and pulmonary valve annuls as -1.10 ± 0.3. The left ventricular end diastolic diameter is -0.93 ± 0.3 while the left ventricular end systolic diameter is -0.05 ± 0.5. The total pooled sample size of the eleven included studies was 9074 and the mean at 95% interval was 824.9 ± 537.344. The pooled mean is presented under the model of the Mean raw (MRAW) column. The heterogeneity discovered among the selected studies was statistically significant.

CONCLUSION

Due to heterogeneity involved in the reportage of the z-scores of cardiac structures and function, it may be necessary for every region to use their z-scores domiciled in their locale. However, having a pooled mean z-score of cardiac structures and function may be useful in the near future.

Whole body sweat rate prediction: outdoor running and cycling exercise

Our aim was to develop and validate separate whole body sweat rate prediction equations for moderate to high-intensity outdoor cycling and running, using simple measured or estimated activity and environmental inputs. Across two collection sites in Australia, 182 outdoor running trials and 158 outdoor cycling trials were completed at a wet-bulb globe temperature ranging from ∼15°C to ∼29°C, with ∼60-min whole body sweat rates measured in each trial. Data were randomly separated into model development (running: 120; cycling: 100 trials) and validation groups (running: 62; cycling: 58 trials), enabling proprietary prediction models to be developed and then validated. Running and cycling models were also developed and tested when locally measured environmental conditions were substituted with participants' subjective ratings for black globe temperature, wind speed, and humidity. The mean absolute error for predicted sweating rate was 0.03 and 0.02 L·h-1 for running and cycling models, respectively. The 95% confidence intervals for running (+0.44 and -0.38 L·h-1) and cycling (+0.45 and -0.42 L·h-1) were within acceptable limits for an equivalent change in total body mass over 3 h of ±2%. The individual variance in observed sweating described by the predictive models was 77% and 60% for running and cycling, respectively. Substituting measured environmental variables with subjective assessments of climatic characteristics reduced the variation in observed sweating described by the running model by up to ∼25%, but only by ∼2% for the cycling model. These prediction models are publicly accessible (https://sweatratecalculator.com) and can guide individualized hydration management in advance of outdoor running and cycling.NEW & NOTEWORTHY We report the development and validation of new proprietary whole body sweat rate prediction models for outdoor running and outdoor cycling using simple activity and environmental inputs. Separate sweat rate models were also developed and tested for situations where all four environmental parameters are not available, and some must be subsequently estimated by the user via a simple rating scale. All models are freely accessible through an online calculator: https://sweatratecalculator.com. These models, via the online calculator, will enable individualized hydration management for training or recreational cycling or running in an outdoor environment.

How to handle a missed or delayed dose of lacosamide in pediatric patients with epilepsy? a mode-informed individual dosing

This study aims to investigate the effects on the pharmacokinetic (PK) of lacosamide (LCM), and to guide the individual dosing regimens for children and ones with poor medication adherence. Population PK research was performed based on 164 plasma samples of 113 pediatric patients aged from 1.75 to 14.42 years old. The PK characteristic of LCM was developed by a one-compartment model with first-order elimination. The typical value of apparent clearance (CL) and apparent volume of distribution (Vd) was 1.91 L·h-1 and 56.53 L respectively. In the final model, the variability of CL was significantly associated with the body surface area (BSA) and elevated uric acid (UA) level. In contrast, the impact of some prevalent anti-seizure medicines, such as valproic acid, levetiracetam, oxcarbazepine, lamotrigine, and perampanel, and gene polymorphisms of Cytochrome P450 (CYP)2C19, ATP-binding cassette (ABC)B1, and ABCC2 had no clinical significance on the PK parameters of LCM. BSA-based dosing regimen of LCM was provided according to Monte Carlo simulation approach; while the dosage should reduce half in patients with an UA level of more than 400 μmol·L-1 comparing with an UA level of 100 μmol·L-1. Individualize remedial doses of about 0.5- to 1.5-fold of regular doses were recommended in six common scenarios of missed or delayed doses, that depended on the delayed time. In current study, the population PK model of LCM in children with epilepsy was developed successfully. The BSA-based dosing regimen and individualized remedial strategy were recommended to guarantee the precise administration of LCM.

Machine learning prediction of hepatic steatosis using body composition parameters: A UK Biobank Study

Non-alcoholic fatty liver disease (NAFLD) has emerged as the most prevalent chronic liver disease worldwide, yet detection has remained largely based on surrogate serum biomarkers, elastography or biopsy. In this study, we used a total of 2959 participants from the UK biobank cohort and established the association of dual-energy X-ray absorptiometry (DXA)-derived body composition parameters and leveraged machine learning models to predict NAFLD. Hepatic steatosis reference was based on MRI-PDFF which has been extensively validated previously. We found several significant associations with traditional measurements such as abdominal obesity, as defined by waist-to-hip ratio (OR = 2.50 (male), 3.35 (female)), android-gynoid ratio (OR = 3.35 (male), 6.39 (female)) and waist circumference (OR = 1.79 (male), 3.80 (female)) with hepatic steatosis. Similarly, A Body Shape Index (Quantile 4 OR = 1.89 (male), 5.81 (female)), and for fat mass index, both overweight (OR = 6.93 (male), 2.83 (female)) and obese (OR = 14.12 (male), 5.32 (female)) categories were likewise significantly associated with hepatic steatosis. DXA parameters were shown to be highly associated such as visceral adipose tissue mass (OR = 8.37 (male), 19.03 (female)), trunk fat mass (OR = 8.64 (male), 25.69 (female)) and android fat mass (OR = 7.93 (male), 21.77 (female)) with NAFLD. We trained machine learning classifiers with logistic regression and two histogram-based gradient boosting ensembles for the prediction of hepatic steatosis using traditional body composition indices and DXA parameters which achieved reasonable performance (AUC = 0.83-0.87). Based on SHapley Additive exPlanations (SHAP) analysis, DXA parameters that had the largest contribution to the classifiers were the features predicted with significant association with NAFLD. Overall, this study underscores the potential utility of DXA as a practical and potentially opportunistic method for the screening of hepatic steatosis.

Normalization of Cardiac Structural dimension and Function to Body Surface Area in South East Nigeria Children

BACKGROUND

Standardizing cardiac valve structures and function to body surface area will help the clinician and surgeons in decision-making.

AIM

To evaluate the z-scores of the sizes of cardiac structures and function and to present them in Gaussian curves and reference values.

MATERIALS AND METHODS

This was a cross-sectional study that involved 300 apparently healthy children. This study was performed among healthy children from birth to 18 years. Children with a normal echocardiogram, those with no chronic illness, no congenital heart defect, and no acquired heart defect were included in the study.

RESULT

The majority fell within the normal limits, as shown in the Gaussian curves. For instance, 40 (13.3%) of atrioventricular (AV) valve diameters were +1 Z-score above the normal, and only 5 (1.7%) were +2 Z-score above the normal. About 9.3% (28/300) had below -2 Z-score below normal, while only 5% had -1 Z-score below normal. Similarly, the left ventricular function z-scores were also derived at -3 Z-scores to +3 Z-scores. The standard reference values were compared with the results obtained from our Z score values. There was no significant difference noted in the Z-scores. P values ranged from 0.07 to 0.84 for all the cardiac structures except for gender, where Z-scores of the mitral valve and left pulmonary artery varied significantly (P = 0.02).

CONCLUSION

Reference values of cardiac structure and function were presented using Z scores, and we noted no significant difference when compared with the Western standard values except for the mitral valve and left pulmonary artery.

Left atrial remodeling in adolescents with obesity evaluated by speckle-tracking echocardiography

BACKGROUND AND AIMS

In adolescents with obesity, a left atrial (LA) enlargement has been reported. However, data regarding its function and its stiffness are missing. The aim of this study was to describe LA morphology and function, using speckle-tracking echocardiography (STE) and to explore their potential determinants in adolescents with obesity.

METHODS

Twenty-eight adolescent women with obesity (13.2 ± 1.4 yr) with an illness duration of 130 ± 27 months and 33 controls (14.1 ± 2.0 yr) underwent a resting echocardiography including an analysis of left ventricular (LV) and LA morphologies and strains. A fasting venous blood sample was performed to biochemical determinations including inflammation markers.

RESULTS

LA volume and stiffness index were increased in adolescents with obesity compared to controls. LA reservoir, conduit and booster pump functions were not different between groups. By stepwise forward multivariate regression analyses, systolic blood pressures, cardiac output and sedimentation rate were the independent determinants of LA volume (p < 0.0001, β-coefficient = 0.460) whereas only the body mass index was an independent determinant of LA stiffness (p = 0.003, β-coefficient = 0.413).

CONCLUSION

In adolescents with obesity, we observed a specific LA remodeling, including higher volume and lower stiffness, which could constitute early signs of an altered LV diastolic function.

Inverse Problem Algorithm-Based Time-Resolved Imaging of Head and Neck Computed Tomography Angiography Contrast Kinetics with Clinical Testification

This study mitigated the challenge of head and neck CT angiography by IPA-based time-resolved imaging of contrast kinetics. To this end, 627 cerebral hemorrhage patients with dizziness, brain aneurysm, stroke, or hemorrhagic stroke diagnosis were randomly categorized into three groups, namely, the original dataset (450), verification group (112), and in vivo testified group (65), in the Affiliated BenQ Hospital of Nanjing Medical University. In the first stage, seven risk factors were assigned: age, CTA tube voltage, body surface area, heart rate per minute, cardiac output blood per minute, the actual injected amount of contrast media, and CTA delayed trigger timing. The expectation value of the semi-empirical formula was the CTA number of the patient's left artery (LA). Accordingly, 29 items of the first-order nonlinear equation were calculated via the inverse problem analysis (IPA) technique run in the STATISTICA 7.0 program, yielding a loss function and variance of 3.1837 and 0.8892, respectively. A dimensionless AT was proposed to imply the coincidence, with a lower AT indicating a smaller deviation between theoretical and practical values. The derived formula was confirmed for the verification group of 112 patients, reaching high coincidence, with average ATavg and standard deviation values of 3.57% and 3.06%, respectively. In the second stage, the formula was refined to find the optimal amount of contrast media for the CTA number of LA approaching 400. Finally, the above procedure was applied to head and neck CTA images of the third group of 65 patients, reaching an average CTA number of LA of 407.8 ± 16.2 and finding no significant fluctuations.

Measured Glomerular Filtration Rate in Live Related Kidney Donors Three Months Post-Kidney Donation: A Single-Center Experience From Western India

Background Glomerular filtration rate (GFR) estimation is pivotal in the evaluation of kidney donors. There are various methods available for assessing GFR, but there has been a lack of consensus on the measurement of GFR and the frequency of renal evaluation after kidney donation. Our study aims to analyze the measured GFR (m-GFR) before and three months after kidney donation and note the compensatory abilities of the remnant kidney in live related kidney donors. Methods This prospective observational study was conducted at the Department of Nephrology, Dr. D. Y. Patil Medical College, Hospital & Research Centre, Pune, from April 2021 to December 2022. The study included 30 donors from both genders aged between 23 and 73 years. The measured GFR was calculated using a technetium-99m diethylene triamine pentaacetic acid (Tc-99m DTPA) scan. We analyzed donor characteristics and various parameters that included demography, anthropometry, blood pressure, and serum creatinine and measured GFR (m-GFR) using a Tc-99m DTPA scan, which was compared before and three months after donor nephrectomy. Results Of the 30 donors, 25 (83.3%) were females and five (16.7%) were males. The mean age of donors was 49.23 ± 12.29 years. The mean body mass index (BMI) was noted to be 24.73 ± 5.58 kg/m2, whereas the mean body surface area (BSA) was 1.59 ± 0.12 m2. In terms of the measured GFR by DTPA scan, pre-donation and post-donation, the average GFR for our population was 103.83 ± 10.07 mL/minute/1.73 m2 and 60.47±6.57 mL/minute/1.73 m2, respectively. The mean measured GFR of remnant kidney increased by 9.21 ± 4.39 mL/minute/1.73 m2 in 28 donors, while two donors had a fall in the mean measured GFR by 6.8 ± 1.69 mL/minute/1.73 m2. Conclusions To safeguard donor health, accurate measurement of GFR at various timelines after kidney donation should be considered as there are various limitations associated with the use of serum creatinine-based GFR estimating equations for solitary kidneys. However, long-term studies are required to analyze the changes in GFR after nephrectomy and determine the adequacy of compensatory changes in the remnant kidney post-kidney donation.

Body surface area is a predictor of maturity status in school children and adolescents

BACKGROUND

Generally, Body surface area (BSA) changes significantly during growth and maturation. These increases portend a possible relationship between body size as determined by BSA with maturational status in children and adolescents.

OBJECTIVE

To determine the relationship between maturity status (MS) obtained by non-invasive anthropometric methods and body surface area (BSA) in children and adolescents of both sexes in a regional population of Chile. Additionally, we sought to verify the type of linear or nonlinear relationship between MS and BSA in both sexes.

METHODS

A descriptive (cross-sectional) study was designed in 950 children and adolescents of both sexes (539 males and 411 females). The age range ranged from 6.0 to 17.9 years. Anthropometric measurements were evaluated: body weight, standing height, sitting height. MS was assessed by means of two non-invasive anthropometric techniques. Both techniques predict peak years of growth velocity (APHV) through a regression equation for each sex. BSA (m2) was estimated by means of the Haycock equation.

RESULTS

The R2 in the linear model is relatively lower (R2 = 0.80 to 0.89 in males and 0.74 to 0.66 in females) in relation to the nonlinear quadratic model (R2 = 0.81 in males and 0.76 to 0.69). The quadratic nonlinear quadratic model reflected an adequate fit (RMSE) for the data set, being in men (RMSE = 1.080 and 1.125), while in women (RMSE = 1.779 and 1.479).

CONCLUSION

BSA is positively associated with MS determined by two non-invasive methods in Chilean children and adolescents: The nonlinear quadratic model was a better fit to the data distribution. The results suggest the use of BSA as a possible predictor of maturity status in Chilean youth.

Impact of BMI z-score on left ventricular mechanics in adolescent girls

Background

Adolescent weight disorders ranging from anorexia nervosa (AN) to obesity (OB) can impact the heart by causing opposite alterations in its morphology, suggesting a direct impact of body mass index (BMI) on the heart. Cardiac function is relatively preserved as assessed by standard echocardiography. However, few studies have used 2D speckle-tracking echocardiography (2D-STE), which can detect subtle alterations of left ventricular (LV) function by evaluating deformations. This study aimed to assess the link between the BMI z-score of adolescent girls and myocardial function.

Methods

Ninety-one adolescent girls comprising 26 AN patients (age 14.6 ± 1.9 years), 28 OB patients (age 13.2 ± 1.4 years), and 37 controls (age 14.0 ± 2.0 years) underwent 2D-STE to assess LV morphology and myocardial global and regional deformations.

Results

The BMI z-score of our population ranged from -4.6 to 5.2. LV morphological remodeling was significantly and positively correlated with the BMI z-score (R2 = 0.456, p < 0.0001 for LV mass). Global longitudinal strain (LS) and regional LS recorded at the mid and apical levels were significantly correlated with the BMI z-score (R2 = 0.196, p = 0.0001 and R2 = 0.274, p < 0.0001, respectively, for apical and medial LS). Circumferential strains and twisting mechanics were not correlated with the BMI z-score. Fibrinogen and systolic blood pressure were the main variables explaining the alteration of LS.

Conclusion

We observed that the BMI z-score had an impact on LV mechanics, especially on medial and apical LS. Neither circumferential nor twisting mechanics were altered by the BMI z-score in adolescent girls.

Studying the effect of donor kidney volume ratios to recipients' body surface area, body mass index, and total body weight on post-transplant graft function

OBJECTIVES

The goal of this study was to retrospectively investigate the relationship between renal transplanted volume indexes (Total kidney volume (TKV)/Body surface area (BSA), Renal parenchymal volume (RPV)/BSA, Renal cortical volume (RCV)/BSA, RPV/Body mass index (BMI), RCV/BMI, RPV/Weight, RCV/Weight), and short- and long-term function of the graft.

METHODS

One-hundred and twelve live donor-recipient pairs from 2017 to 2018, whose donors underwent preoperative renal computed tomography angiography and recipients survived during 12 months of follow-up, were included in this study.

RESULTS

The crude and adjusted linear regressions for the effect of volume measurements by voxel and ellipsoid methods on the estimated glomerular filtration rate (eGFR) at different post-transplantation times demonstrated that the RPV/weight ratio had the most substantial crude effect on the eGFR 12 months and 4 years after renal transplant. Receiver operating characteristic (ROC) curves for six different renal volume ratios demonstrated no significant difference between these ratios in terms of discriminative ability (p value < 0.05). A strong direct correlation between TKV calculated by the ellipsoid formula with RPV and RCV measured using OsiriX software was noted. Analysis of ROC curves for renal volume indices has demonstrated fair to good discriminative ability of our cut-off points to estimate 4-year post-transplantation eGFR > 60 mL/min.

CONCLUSION

Renal transplant recipients' volume indices, such as RPV/weight, had strong correlations with eGFR at different points in time, and renal transplant recipients with the volume ratios higher than our cut-off points had a good chance of having a 4-year post-transplantation eGFR higher than 60 mL/min.

Prevalence of pre-eclampsia and adverse pregnancy outcomes in women with pre-existing cardiomyopathy: a multi-centre retrospective cohort study

Pre-eclampsia is associated with postnatal cardiac dysfunction; however, the nature of this relationship remains uncertain. This multicentre retrospective cohort study aimed to determine the prevalence of pre-eclampsia in women with pre-existing cardiac dysfunction (left ventricular ejection fraction < 55%) and explore the relationship between pregnancy outcome and pre-pregnancy cardiac phenotype. In this cohort of 282 pregnancies, pre-eclampsia prevalence was not significantly increased (4.6% [95% C.I 2.2-7.0%] vs. population prevalence of 4.6% [95% C.I. 2.7-8.2], p = 0.99); 12/13 women had concurrent obstetric/medical risk factors for pre-eclampsia. The prevalence of preterm pre-eclampsia (< 37 weeks) and fetal growth restriction (FGR) was increased (1.8% vs. 0.7%, p = 0.03; 15.2% vs. 5.5%, p < 0.001, respectively). Neither systolic nor diastolic function correlated with pregnancy outcome. Antenatal ß blockers (n = 116) were associated with lower birthweight Z score (adjusted difference - 0.31 [95% C.I. - 0.61 to - 0.01], p = 0.04). To conclude, this study demonstrated a modest increase in preterm pre-eclampsia and significant increase in FGR in women with pre-existing cardiac dysfunction. Our results do not necessarily support a causal relationship between cardiac dysfunction and pre-eclampsia, especially given the population's background risk status. The mechanism underpinning the relationship between cardiac dysfunction and FGR merits further research but could be influenced by concomitant ß blocker use.

Analysis of therapy monitoring in the International Congenital Adrenal Hyperplasia Registry

OBJECTIVE

Congenital adrenal hyperplasia (CAH) requires exogenous steroid replacement. Treatment is commonly monitored by measuring 17-OH progesterone (17OHP) and androstenedione (D4).

DESIGN

Retrospective cohort study using real-world data to evaluate 17OHP and D4 in relation to hydrocortisone (HC) dose in CAH patients treated in 14 countries.

PATIENTS

Pseudonymized data from children with 21-hydroxylase deficiency (21OHD) recorded in the International CAH Registry.

MEASUREMENTS

Assessments between January 2000 and October 2020 in patients prescribed HC were reviewed to summarise biomarkers 17OHP and D4 and HC dose. Longitudinal assessment of measures was carried out using linear mixed-effects models (LMEM).

RESULTS

Cohort of 345 patients, 52.2% female, median age 4.3 years (interquartile range: 3.1-9.2) were taking a median 11.3 mg/m2 /day (8.6-14.4) of HC. Median 17OHP was 35.7 nmol/l (3.0-104.0). Median D4 under 12 years was 0 nmol/L (0-2.0) and above 12 years was 10.5 nmol/L (3.9-21.0). There were significant differences in biomarker values between centres (p < 0.05). Correlation between D4 and 17OHP was good in multiple regression with age (p < 0.001, R2  = 0.29). In longitudinal assessment, 17OHP levels did not change with age, whereas D4 levels increased with age (p < 0.001, R2  = 0.08). Neither biomarker varied directly with dose or weight (p > 0.05). Multivariate LMEM showed HC dose decreasing by 1.0 mg/m2 /day for every 1 point increase in weight standard deviation score.

DISCUSSION

Registry data show large variability in 17OHP and D4 between centres. 17OHP correlates with D4 well when accounting for age. Prescribed HC dose per body surface area decreased with weight gain.

Relationship between ultrasound-measured spleen, liver and anthropometry of children living in a rural community in southwest Nigeria: a cross-sectional study

BACKGROUND

Ultrasonography is noninvasive, relatively inexpensive and useful for resource-poor settings. US spleen and liver sizes have been observed to differ among populations, so there is a need for reference values for different geographic populations.

OBJECTIVE

To describe the sizes of the spleen and liver of children living in a rural community in southwest Nigeria and assess the relationship between these measurements and the children's anthropometry.

MATERIALS AND METHODS

We conducted a community-based cross-sectional study among 358 apparently healthy children ages 1-14 years. We obtained the participants' weights, heights, body mass index and body surface area. They underwent US imaging to obtain longitudinal measurements of their spleen and liver. We used independent t-test to compare means, and linear regression analysis to assess relationships between continuous data. The significance level was set as P < 0.05.

RESULTS

There were more girls (181; 50.6%). Most children were ages 1-5 years (172; 48.0%). The body surface area had significantly strong positive relationships with US spleen size (r = 0.769; R² = 0.592; P < 0.0001) and US liver size (r = 0.819; R² = 0.671; P < 0.0001) but body mass index had weak positive relationships.

CONCLUSION

This study contributes to data on US spleen and liver sizes of Nigerian children. The findings buttress observations that body surface area strongly correlates with US spleen and liver measurements. It is recommended that more studies be conducted among Nigerian children to generate a robust pool of data that are useful for creating homogeneous formulae to ease interpretation of US measurements of these intraabdominal organs.

Cardiac Remodeling and Its Determinants in Anorexia Nervosa Adolescents: Impact of Weight Recovery

Cardiovascular alterations in anorexia nervosa (AN) adolescents include bradycardia and decreased systolic blood pressure and left ventricular mass. However, their determinants remain poorly understood. We assessed the associations between morphological and functional left ventricular (LV) remodeling, autonomic control by heart rate variability (HRV) analysis, thyroid hormones and brain natriuretic peptide (BNP) levels in AN female adolescents without or with weight recovery (WR). Fifty-nine female adolescents including 16 AN patients without WR (mean age 13.9 years (10−16)), 10 AN patients with WR (15.7 years (12−18)) and 33 controls (14.1 years (10−18)) underwent night heart rate (HR) recording to measure HRV (and especially SD1/SD2, the ratio between instantaneous (SD1) and long-term (SD2) standard deviation of R-R intervals, reflecting sympatho-vagal balance), speckle tracking echocardiography to assess LV global longitudinal strain (GLS) and blood test for dosage of tri-iodothyronine (T3) hormone and NT-proBNP. Compared to controls, AN patients without WR presented with lower HR (55 ± 7 vs. 68 ± 6 bpm; p < 0.001), parasympathetic hyperactivity, and higher GLS (−19.2 ± 1.8 vs. −16.9 ± 2.8%; p = 0.009). These alterations were partly abolished in AN patients with WR. In a multivariate regression analysis, T3 was the main factor explaining the variance of SD1/SD2, a sympatho-vagal balance marker. NT-proBNP levels were not correlated with cardiac alterations. AN patients had parasympathetic hyperactivity linked with their rate of T3, and a higher GLS. These alterations were partly restored in AN patients with WR.

Left Ventricular Strains and Myocardial Work in Adolescents With Anorexia Nervosa

Background

Anorexia nervosa (AN) is accompanied by bradycardia, low blood pressure (BP) and cardiac morphological remodeling. Systolic and diastolic functions are relatively preserved when assessed by standard ultrasound methods. However, novel advances based on speckle tracking echocardiography (STE), that could detect subtle and early alterations of left ventricular (LV) function, remained poorly used in AN patients.

Objective

The aim of this study was to assess the cardiac function of AN patients by evaluating LV myocardial strains, myocardial work (MW) and LV mechanical dispersion. We hypothesized that LV strains and global myocardial work would be decreased and LV twisting mechanisms enhanced to preserve the systolic function.

Methods

Fifty-nine adolescents including 26 women AN patients (14.6 ± 1.9 yrs. old) with a mean duration of AN of 19 ± 9 months and 33 controls (14.1 ± 2.0 yrs. old) underwent STE to assess LV morphology and myocardial regional strains.

Results

The global longitudinal strain (GLS) was higher in AN patients compared to controls (−18.8 ± 2.0 vs. −16.9 ± 2.8%, p = 0.006). The area under the pressure-strain loop, representing the global MW was not altered but was shifted to the left and downwards in AN patients, due to their lower BP and higher GLS. Intraventricular mechanical dispersion was similar in both groups. Circumferential strains, twisting/untwisting mechanics were preserved.

Conclusion

Our results strongly support that the cardiac morphological remodeling observed in our AN patients was associated with normal ventricular regional myocardial functions. Only GLS was higher in AN patients, but its clinical significance remains to be demonstrated.

Automatic SCOring of Atopic Dermatitis using Deep Learning (ASCORAD): A Pilot Study

Atopic dermatitis (AD) is a chronic, itchy skin condition that affects 15–20% of children but may occur at any age. It is estimated that 16.5 million US adults (7.3%) have AD that initially began at age >2 years, with nearly 40% affected by moderate or severe disease. Therefore, a quantitative measurement that tracks the evolution of AD severity could be extremely useful in assessing patient evolution and therapeutic efficacy. Currently, SCOring Atopic Dermatitis (SCORAD) is the most frequently used measurement tool in clinical practice. However, SCORAD has the following disadvantages: (i) time consuming—calculating SCORAD usually takes about 7–10 minutes per patient, which poses a heavy burden on dermatologists and (ii) inconsistency—owing to the complexity of SCORAD calculation, even well-trained dermatologists could give different scores for the same case. In this study, we introduce the Automatic SCORAD, an automatic version of the SCORAD that deploys state-of-the-art convolutional neural networks that measure AD severity by analyzing skin lesion images. Overall, we have shown that Automatic SCORAD may prove to be a rapid and objective alternative method for the automatic assessment of AD, achieving results comparable with those of human expert assessment while reducing interobserver variability.

Evaluation of nine formulas for estimating the body surface area of children with hematological malignancies

OBJECTIVES

Body surface area (BSA) is an important parameter in clinical practice for children. To find out the most accurate BSA formula for Chinese children, nine formulas were compared.

METHODS

This single-center study comprised children who were diagnosed with acute lymphoblastic leukemia and treated with anticancer agents in a specialized children's hospital in China from January 2017 to December 2020. The BSA values were calculated using the formulas from Boyd, Banerjee and Bhattacharya, Costeff, Fujimoto and Watanabe, Haycock, Gehan and George, Mosteller, Stevenson and a Pediatrics textbook. The arithmetic mean of formulas was calculated as the "gold standard" for comparison.

RESULTS

A total of 666 children (389 males and 277 females) were included. All nine formulas showed a strong positive correlation with the "gold standard." Underestimation was observed with the Banerjee and Bhattacharya, Fujimoto and Watanabe formulas. The Gehan and George formula showed overestimation. Values estimated from the Haycock and Mosteller formulas were the closest to the mean BSA.

CONCLUSION

The Haycock and Mosteller formulas are the most recommended formulas for Chinese children with hematological malignancies.

Estimation of body surface area in neonates, infants, and children using body weight alone

BACKGROUND

The aim of this study was to use Body Surface Area (BSA) data calculated with the Mosteller equation to test potential new equations that estimate BSA using Body Weight (BW) alone in children aged 0-18 years.Mosteller's equation, the golden standard at our hospital, was used to calculate the BSA in infants and children aged 0-18 years using BW and height data from 27,440 hospital visits by 20,635 patients over one year.

METHODS

The best fit of three nonlinear regression equations (third-order polynomial, Meeh-type, and modified Boyd self-adjusting-type) to a plot of the calculated Mosteller BSA values versus BW was then investigated. The correlation between the BSA values estimated by these equations and the Mosteller BSA values was established by the Spearman rank correlation test. Bias and precision were evaluated as outlined by Sheiner and Beal. Measured and estimated BSA values were compared using the Eksborg plot.

RESULTS

The estimated BSA values from all three equations and the BSA values from the Mosteller equation were closely correlated (P < .0001). The third-order polynomial and Meeh-type equations overestimated BSA by 0.13% and 0.40%, respectively, while the Boyd self-adjusted-type equation underestimated BSA by 0.060%. For the entire pediatric population, the best fit was obtained with the Meeh-type equation: 99.2% of the Meeh/Mosteller BSA ratios were within the range of 0.9-1.1 when compared with 98.3% and 97.2% for the polynomial and Boyd-type equations, respectively.

CONCLUSION

A single Meeh-type equation can be used to predict the results of Mosteller equation when H is not available with high precision and accuracy in children aged 0-18 years, including term neonates. We now plan to include the results of this study in CPOE systems in Sweden to improve drug dosage in all children.

Model-Oriented Dose Optimization of Voriconazole in Critically Ill Children

This study aimed to employ a population pharmacokinetic (PK) model to optimize the dosing regimen of voriconazole (VRC) in children with a critical illness. A total of 99 children aged from 0.44 to 13.58 years were included in this study. The stability and predictive performance of the final model were evaluated by statistical and graphical methods. The optimal dosing regimen was proposed for children with different body weights, CYP2C19 phenotypes, and coadministrations with omeprazole. The PK of VRC was described by a two-compartment model with nonlinear Michaelis-Menten elimination. Body weight, CYP2C19 phenotype, and omeprazole were significant covariates on the maximum velocity of elimination (V_max), which had an estimated typical value of 18.13 mg · h^-1. Bayesian estimation suggested that the dose-normalized concentration and total exposure (peak concentration [C_max]/D, trough concentration [C_min]/D, and area under the concentration-time curve over 24 h [AUC₂₄]/D) were significantly different between extensive metabolizer (EM) patients and poor metabolizer (PM) patients. To achieve the target concentration early, two loading doses of 9 mg · kg^-1 of body weight every 12 h (q12h) were reliable for most children, whereas three loading doses of 6 to 7.5 mg · kg^-1 q8h were warranted for young children weighing ≤18 kg (except for PM patients). The maintenance doses decreased about 30 to 40% in PM patients compared to that in EM patients. For children aged <2 years, in EM patients, the maintenance dose could be as high as 9 mg · kg^-1. The maintenance dose of VRC was supposed to decrease slightly when coadministered with omeprazole. A population PK model of intravenous VRC for critically ill children has been successfully developed. It is necessary to adjust dosing regimens according to the CYP2C19 genotype. Optimal dosing regimens have been recommended based on the final model.

Six commonly used empirical body surface area formulas disagreed in young children undergoing corrective heart surgery

AIM

Formulas for empirical body surface area (BSA), which is used to estimate body size and standardise physiological parameters, may disagree in children. We compared six commonly used BSA formulas-Du Bois, Boyd, Costeff, Haycock, Meban and Mosteller-in a surgical cohort.

METHODS

This retrospective single-centre cohort study comprised 68 children who had corrective heart surgery at Skåne University Children's Hospital, Lund, Sweden, from February 2010 to March 2017.

RESULTS

The children (51% female) underwent surgery at a mean weight of 7.0 kilograms (range 2.7-14.1 kg) and a mean age 11 months (range 0-43 months). All the BSA formulas showed good correlation with mean BSA, but there were considerable variations between them. Mosteller's formula was exactly the same as the mean BSA (bias 0.000). The Du Bois and Boyd formulas had the largest mean BSA deviations (bias -0.012 and 0.015). Costeff's formula showed good agreement with mean BSA, Haycock's formula showed minimal overestimation and Meban's formula demonstrated a systemic error in older children.

CONCLUSION

Commonly used BSA formulas did not agree in young children undergoing heart surgery, but they were all close to the overall mean of the six formulas, with the Mosteller formula producing the same value.

Porcine Small Intestinal Submucosa Mitral Valve Material Responses Support Acute Somatic Growth

Background: Conceptually, a tissue engineered heart valve would be especially appealing in the pediatric setting since small size and somatic growth constraints would be alleviated. In this study, we utilized porcine small intestinal submucosa (PSIS) for valve replacement. Of note, we evaluated the material responses of PSIS and subsequently its acute function and somatic growth potential in the mitral position. Methods and Results: Material and mechanical assessment demonstrated that both fatigued 2ply (∼65 μm) and 4ply (∼110 μm) PSIS specimens exhibited similar failure mechanisms, but at an accelerated rate in the former. Specifically, the fatigued 2ply PSIS samples underwent noticeable fiber pullout and recruitment on the bioscaffold surface, leading to higher yield strength (p < 0.05) and yield strain (p < 0.05) compared to its fatigued 4ply counterparts. Consequently, 2ply PSIS mitral valve constructs were subsequently implanted in juvenile baboons (n = 3). Valve function was longitudinally monitored for 90 days postvalve implantation and was found to be robust in all animals. Histology at 90 days in one of the animals revealed the presence of residual porcine cells, fibrin matrix, and host baboon immune cells but an absence of tissue regeneration. Conclusions: Our findings suggest that the altered structural responses of PSIS, postfatigue, rather than de novo tissue formation, are primarily responsible for the valve's ability to accommodate somatic growth during the acute phase (90 days) following mitral valve replacement. Impact Statement Tissue engineered heart valves (TEHVs) offer the potential of supporting somatic growth. In this study, we investigated a porcine small intestinal submucosa bioscaffold for pediatric mitral heart valve replacement. The novelty of the study lies in identifying material responses under mechanical loading conditions and its effectiveness in being able to function as a TEHV. In addition, the ability of the scaffold valve to support acute somatic growth was evaluated in the Baboon model. The current study contributes toward finding a solution for critical valve diseases in children, whose current prognosis for survival is poor.

Doses of chloroquine in the treatment of malaria by Plasmodium vivax in patients between 2 and 14 years of age from the Brazilian Amazon basin

BACKGROUND

A total dose of chloroquine of 25 mg/kg is recommended by the World Health Organization (WHO) to treat malaria by Plasmodium vivax. In several endemic areas, including the Brazilian Amazon basin, anti-malarial drugs are dispensed in small plastic bags at a dosing regimen based on age. This practice can lead to suboptimal dosing of the drug, which can impact treatment outcomes. The aim of the present study was to estimate the extent of sub-dosing of chloroquine in children and adolescents with vivax malaria using an age-based dose regimen, in addition to investigating the influence of age on the plasma concentrations of chloroquine and desethylchloroquine.

METHODS

A study of cases was conducted with male patients with a confirmed infection by P. vivax, ages 2 to 14 years, using a combined regimen of chloroquine and primaquine. Height, weight and body surface area were determined at admission on the study. The total dose of chloroquine administered was estimated based on the weight and on the body surface area of the study patients. Chloroquine and desethylchloroquine were measured on Day 7 in each patient included in the study by a high-performance liquid chromatographic method with fluorescence detection.

RESULTS

A total of 81 patients were enrolled and completed the study. The median age was 9 years (2-14 years). All patients presented negative blood smears at 42 days follow-up. The total dose of chloroquine ranged from 13.1 to 38.1 mg/kg. The percentage of patients with a total dose of the drug below 25 mg/kg ranged from 29.4 to 63.6%. The total dose of chloroquine administered based on BSA ranged from 387 to 1079 mg/m2, increasing with age. Plasma chloroquine concentrations ranged from 107 to 420 ng/ml, increasing with age. For desethylchloroquine, the plasma concentrations ranged from 167 to 390 ng/ml, with similar values among age-groups.

CONCLUSION

The data demonstrated the widespread exposure of children and adolescents to suboptimal doses of chloroquine in the endemic area investigated.

Analysis of concordance with antiemetic guidelines in pediatric, adolescent, and young adult patients with cancer using a large-scale administrative database

Object

The appropriate use of antiemetics is important for the prevention of chemotherapy‐induced nausea and vomiting (CINV); however, little is known about the rate of concordance with antiemetic guidelines for CINV in the field of pediatric, adolescent, and young adult.

Methods

Using the Diagnosis Procedure Combination system in Japan, we identified patients <30 years of age who were diagnosed with cancer between July 2010 and March 2016. We have assessed concordance with the ASCO antiemetic guidelines for each emetic risk category of chemotherapeutic drugs. Furthermore, we have assessed the risk factors of discordance with the antiemetic guidelines using a logistic regression.

Results

In total, 21 106 patients who underwent chemotherapy were included. The rates of concordance with the guidelines in each emetic risk category of chemotherapeutic drugs were 51.1% in high risk, ≥18 years of age; 21.5% in high risk, <18 years of age; 32.1% in moderate risk; 52.0% in low risk; and 51.6% in minimal risk. The main reason for the discordance was underuse of antiemetics, especially steroids. The factors for discordance were younger age, use of moderate and high emetic risk chemotherapeutic drugs, hematological malignancy, and brain tumor.

Conclusion

There is substantial scope to improve the antiemetic practice and reduce the risk of discordance with the antiemetic guidelines in pediatric, adolescent, and young adult patients. The risk factors are different from those in adults. Further investigations to evaluate the causes of discordance are warranted.

A new population pharmacokinetic model for vancomycin in patients with variable renal function: Therapeutic drug monitoring based on extended covariate model using CKD-EPI estimation

WHAT IS KNOWN AND OBJECTIVE: Although patients may have received vancomycin therapy with therapeutic drug monitoring (TDM), those treated with high-strength and long-term vancomycin therapy might have unstable and time-varying renal function. The methods used to estimate renal function should not be considered interchangeable with pharmacokinetic (PK) modeling and model-based estimation of vancomycin pharmacokinetics. While Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) for renal function estimation has been widely integrated into clinical practice, a population PK model including CKD-EPI has not been established. The study was aimed at developing a new population PK model for optimal vancomycin prediction in patients with time-varying and variable renal function to evaluate the interchangeability of estimation methods. METHODS: The most suitable population PK model was explored and evaluated using non-linear mixed-effect modelling for the best fit of vancomycin concentrations from patients who needed to maintain high trough vancomycin concentrations of >10 mg/L or >15 mg/L. Renal function was estimated using the Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD) and CKD-EPI equations. NONMEM 7.4 was used to develop the population PK model. RESULTS: A total of 328 vancomycin concentrations in 99 patients were used to develop the population PK model. Vancomycin pharmacokinetics was best described by a two-compartment model. The CKD-EPI equation for vancomycin clearance was included in the final model among the estimation methods of renal function. A new covariate model, including extended covariate parameters that explain changes in renal function from the population-predicted value and individual dosing time, provided the best explanation for vancomycin pharmacokinetics among the various models tested. WHAT IS NEW AND CONCLUSION: A new extended covariate model for vancomycin using the CKD-EPI method may afford suitable dose adjustment for high-strength and long-term vancomycin therapy that results in unstable renal function.

Formulae Evaluation for Estimating Body Surface Area of Korean Children

Body surface area (BSA) is an important parameter in the conduct of human exposure studies and in clinical processes in children. The aim of this paper was to compare seven BSA formulas and to find out which of these formulas is appropriate for use with Korean children. Body surface area was calculated according to age, age-group and BMI-group using the height and weight data of Korean children (n = 4899) ages 1 to 18 from Korea National Health and Nutrition Examination Survey (2012-2014). We used the formulas of Banerjee and Bhattacharya (1961), Fujimoto and Watanabe (1969), US EPA (1985), Gehan and George (1970), Boyd (1935), Haycock et al (1978) and Mosteller (1987). The average values of the seven formulas were calculated and used as norm values for comparison. All predictions showed a strong positive correlation with the overall average BSA values. Overestimations were observed on the calculations of Gehan and George (1970), US EPA (1985) and Boyd (1935) formulas. Banerjee and Bhattacharya (1961) and Fujimoto and Watanabe (1969) values showed underestimations and the largest error size of 0.027 m² for all ages. BSA estimates of Mosteller (1987) and Haycock et al (1978) were found to be closer to the overall average BSA values with the least error size of 0.004 m². Mosteller's formula is recommended for use in the conduct of human exposure studies and in clinical practice among Korean children, although Haycock et al formula is appropriate for children from 1 to 2 years old.

Evaluation of the paediatric dose of chloroquine in the treatment of Plasmodium vivax malaria

BACKGROUND

Chloroquine (CQ) continues to be the first-line medication used worldwide in the treatment of Plasmodium vivax malaria. The dose recommended by the World Health Organization is 25 mg/kg independently of the age of the subject. Nonetheless, the pharmacokinetics and pharmacodynamics of drugs in children are different from those in adults and may influence the drug concentrations in blood and become risk factors for therapeutic failure and/o resistance to CQ.

METHODS

This study is a secondary analysis of the data from a clinical trial in which children over 5 years of age were administered 25 mg/kg of CQ, and CQ concentrations in blood were measured at day 7 of follow-up. Models of regression and comparison were used to evaluate and compare the CQ dose taken per kg/body weight, the CQ dose calculated based on body surface area, CQ levels in blood on day 7 and the age of the population.

RESULTS

The younger the study population the greater the difference between the dose per kg/body weight (real dose) and that calculated according to the BSA (theoretical dose). The difference between the two doses was -181.206 mg in the 5-9 years of age group (CI 95 % -195.39; -167.02 mg) and -71.39 mg (CI 95 % -118.61; -23.99 mg) in the 10-14-year-old group. The CQ concentrations in blood on day 7 differed in patients over and under 15 years (p = 0.008). A negative correlation was found between the real and theoretical dose (difference in dose) and the age in years (R2 = 0.529, p = 0.001). A negative correlation was also found between the difference in dose (mg) and CQ concentrations on day 7 (ng/ml) (r = -0.337, p = 0.001). Children under 15 years were found to have a higher rate of therapeutic failure than those over 15 (28 vs 4.2 %, respectively) (Kaplan-Meier p = 0.005).

CONCLUSIONS

A CQ dose of 25 mg/kg for the treatment of P. vivax malaria may be too low in children as demonstrated by the reduction in CQ concentrations in blood at day 7 of follow-up. This under-dosage is probably associated with the higher rate of therapeutic failure found in children under 15 years (28 vs 4.3 %). These results suggest the need to review the paediatric doses of CQ currently used.