The fate of anti-HLA antibodies following liver transplantation.

Introduction: Liver transplant recipients may have pre-formed anti-HLA antibodies directed to mismatched HLA of the liver donor (donor specific antibodies, DSA) or not directed to the liver donor (non-donor specific, non-DSA). We observed the fate of these antibodies (DSA and non-DSA) at 12 months after transplant. Methods: Patients transplanted between 4/2015 and 12/2018 (N = 216) who had anti-HLA antibody measurements at both transplant and 12 months posttransplant (N = 124) and with DSAs at transplant (N = 31) were considered informative for a paired analysis of the natural history of DSA and non-DSA following liver transplantation. Results: Class I DSAs and non-DSAs decreased between transplant and 12 months; however, Class I DSAs essentially disappeared by 12 months while Class I non-DSAs did not. Anti-HLA Class II DSAs performed differently. While there was a significant drop in values between transplant and 12 months, these antibodies mostly persisted at a low level. Discussion: Our study demonstrated a significant difference in the kinetics of DSA compared to non-DSA following liver transplantation, most profoundly for anti-HLA Class I antibodies. Class I DSAs were mostly absent at 12 months while Class II DSAs persisted, although at lower levels. The mechanisms of reduction in anti-HLA antibodies following liver transplantation are not completely understood and were not pursued as a part of this study. This detailed analysis of Class I and Class II DSAs and non-DSAs represents and important study to explore the change in antibodies at one year from liver transplantation.

Evaluating User Experience and DNA Yield from Self-Collection Devices.

BACKGROUND: The COVID-19 pandemic emphasized an urgent need for devices used in the self-collection of biospecimens in an evolving patient care system. The mailing of biospecimen self-collection kits to patients, with samples returned via mail, provides a more convenient testing regimen, but could also impart patient sampling variabilities. User compliance with device directions is central to downstream testing of collected biospecimens and clear instructions are central to this goal. METHODS: Here, we performed an evaluation of 10 oral DNA collection devices involving either swab or saliva self-collection and analyzed ease of use and comfort level with a device, as well as DNA recovery quantity/quality and sample stability. RESULTS: We show that while these DNA quality/quantity metrics are comparable between devices, users prefer direct saliva collection over swab-based devices. CONCLUSIONS: This information is useful in guiding future experiments including their use in human RNA, microbial, or viral sample collection/recovery and their use in clinical testing.

Peripheral Retinal Haemorrhages in a Patient with MOG-Associated Optic Neuritis.

A 15-year-old female presented with headaches and bilateral vision loss. Fundoscopic examination revealed bilateral optic nerve oedema as well as peripheral retinal haemorrhages. Magnetic resonance imaging of the brain showed findings consistent with bilateral optic neuritis. The patient was started on high dose intravenous corticosteroids but her vision failed to improve. The presence of retinal haemorrhages raised concern that a vasculitis was underlying her symptoms, prompting an extensive work-up, which was unrevealing. Plasmapheresis was initiated and the patient's vision eventually improved to 20/20 in both eyes. Ultimately, she was found to be positive for myelin oligodendrocyte glycoprotein (MOG) antibodies, consistent with a diagnosis of MOG-associated optic neuritis. The patient's course was typical for MOG-associated optic neuritis but her peripheral retinal haemorrhages were atypical, which created diagnostic uncertainty. It is important to be aware of the possibility of retinal findings in this disease. We also review potential causes for retinal haemorrhages in optic neuritis.

Analysis of a beta-lactam allergy assessment protocol challenging diverse reported allergies managed by an antimicrobial stewardship program.

Objective: To assess the safety and efficacy of a novel beta-lactam allergy assessment algorithm managed by an antimicrobial stewardship program (ASP) team. Design: Retrospective analysis. Setting: One quaternary referral teaching hospital and one tertiary care teaching hospital in a large western Pennsylvania health network. Patients or participants: Patients who received a beta-lactam challenge dose under the beta-lactam allergy assessment algorithm. Interventions: A beta-lactam allergy assessment protocol was designed and implemented by an ASP team. The protocol risk stratified patients' reported allergies to identify patients appropriate for a challenge with a beta-lactam antibiotic. This retrospective analysis assessed the safety and efficacy of this protocol among patients receiving a challenge dose from November 2017 to July 2021. Results: Over a 45-month period, 119 total patients with either penicillin or cephalosporin allergies entered the protocol. Following a challenge dose, 106 (89.1%) patients were treated with a beta-lactam. Eleven patients had adverse reactions to a challenge dose, one of which required escalation of care to the intensive care unit. Of the patients with an unknown or low-risk reported allergy, 7/66 (10.6%) had an observed adverse reaction compared to 3/42 (7.1%) who had an observed reaction with a reported high-risk or anaphylactic allergy. Conclusions: Our implemented protocol was safe and effective, with over 90% of patients tolerating the challenge without incident and many going on to receive indicated beta-lactam therapy. This protocol may serve as a framework for other inpatient ASP teams to implement a low-barrier allergy assessment led by ASP teams.

Dietary Intake and Arterial Stiffness in Children and Adolescents: A Systematic Review.

Arterial stiffness is a risk factor for cardiovascular disease that is affected by diet. However, research understanding how these dietary risk factors are related to arterial stiffness during childhood is limited. The purpose of this review was to determine whether various dietary factors were associated with arterial stiffness in the pediatric population. Five databases were systematically searched. Intervention studies, cross-sectional and cohort studies were included that investigated nutrient or food intake and outcomes of arterial stiffness, primarily measured by pulse wave velocity (PWV) and augmentation index (AIx), in the pediatric population (aged 0-18 years). A final 19 studies (six intervention and 13 observational) were included. Only two intervention studies, including a vitamin D and omega-3 supplementation trial, found protective effects on PWV and AIx in adolescents. Findings from observational studies were overall inconsistent and varied. There was limited evidence to indicate a protective effect of a healthy dietary pattern on arterial stiffness and an adverse effect of total fat intake, sodium intake and fast-food consumption. Overall, results indicated that some dietary factors may be associated with arterial stiffness in pediatric populations; however, inconsistencies were observed across all study designs. Further longitudinal and intervention studies are warranted to confirm the potential associations found in this review.

The varved succession of Crawford Lake, Milton, Ontario, Canada as a candidate Global boundary Stratotype Section and Point for the Anthropocene series.

An annually laminated succession in Crawford Lake, Ontario, Canada is proposed for the Global boundary Stratotype Section and Point (GSSP) to define the Anthropocene as a series/epoch with a base dated at 1950 CE. Varve couplets of organic matter capped by calcite precipitated each summer in alkaline surface waters reflect environmental change at global to local scales. Spheroidal carbonaceous particles and nitrogen isotopes record an increase in fossil fuel combustion in the early 1950s, coinciding with early fallout from nuclear and thermonuclear testing - 239+240Pu and 14C:12C, the latter more than compensating for the effects of old carbon in this dolomitic basin. Rapid industrial expansion in the North American Great Lakes region led to enhanced leaching of terrigenous elements by acid precipitation during the Great Acceleration, and calcite precipitation was reduced, producing thin calcite laminae around the GSSP that is marked by a sharp decline in elm pollen (Dutch Elm disease). The lack of bioturbation in well-oxygenated bottom waters, supported by the absence of fossil pigments from obligately anaerobic purple sulfur bacteria, is attributed to elevated salinities and high alkalinity below the chemocline. This aerobic depositional environment, highly unusual in a meromictic lake, inhibits the mobilization of Pu, the proposed primary stratigraphic guide for the Anthropocene.

Anti-PD-1 and Extended Half-life IL2 Synergize for Treatment of Murine Glioblastoma Independent of Host MHC Class I Expression.

Glioblastoma (GBM) is the most common malignant brain tumor in adults, responsible for approximately 225,000 deaths per year. Despite preclinical successes, most interventions have failed to extend patient survival by more than a few months. Treatment with anti-programmed cell death protein 1 (anti-PD-1) immune checkpoint blockade (ICB) monotherapy has been beneficial for malignant tumors such as melanoma and lung cancers but has yet to be effectively employed in GBM. This study aimed to determine whether supplementing anti-PD-1 ICB with engineered extended half-life IL2, a potent lymphoproliferative cytokine, could improve outcomes. This combination therapy, subsequently referred to as enhanced checkpoint blockade (ECB), delivered intraperitoneally, reliably cures approximately 50% of C57BL/6 mice bearing orthotopic GL261 gliomas and extends median survival of the treated cohort. In the CT2A model, characterized as being resistant to CBI, ECB caused a decrease in CT2A tumor volume in half of measured animals similar to what was observed in GL261-bearing mice, promoting a trending survival increase. ECB generates robust immunologic responses, features of which include secondary lymphoid organ enlargement and increased activation status of both CD4 and CD8 T cells. This immunity is durable, with long-term ECB survivors able to resist GL261 rechallenge. Through employment of depletion strategies, ECB's efficacy was shown to be independent of host MHC class I-restricted antigen presentation but reliant on CD4 T cells. These results demonstrate ECB is efficacious against the GL261 glioma model through an MHC class I-independent mechanism and supporting further investigation into IL2-supplemented ICB therapies for tumors of the central nervous system.

Evaluation of a Salt-Reduction Consumer Awareness Campaign Targeted at Parents Residing in the State of Victoria, Australia.

From 2015 to 2020 a state-wide salt-reduction initiative was launched in Victoria, Australia, including an awareness campaign focused on parents with children <18 years of age. To evaluate the impact of the campaign on salt-related knowledge, attitudes and behaviors (KABs) we have assessed trends in salt-related KAB pre- and post-delivery of the campaign in parents, as well as within the wider adult population. Cross-sectional surveys of adults aged 18-65 years were undertaken pre- (2015: n = 821 parents; n = 1527 general sample) and post-campaign (2019: n = 935 parents; n = 1747 general sample). KABs were assessed via an online survey. Data were analyzed with regression models and adjusted for covariates. Among parents, around one-quarter of salt-related KABs shifted in a positive direction, but changes were small: there was a 6% (95% CI 2, 11%) increase in the percentage who knew the main source of salt in the diet and reductions in the percentage who reported placing a salt shaker on the table (-8% (95%CI -12, -3)) and that their child added salt at the table (-5% (95% -9, -0.2)). Among the wider adult sample, even fewer shifts in KAB were observed, with some behaviors worsening at follow-up. These findings indicate that this consumer awareness campaign had minimum impact.

Evaluation of a state-wide intervention on salt intake in primary schoolchildren living in Victoria, Australia.

OBJECTIVE: In 2015, the Victorian Salt Reduction Partnership launched a 4-year multifaceted salt reduction intervention designed to reduce salt intake by 1 g/d in children and adults living in Victoria, Australia. Child-relevant intervention strategies included a consumer awareness campaign targeting parents and food industry engagement seeking to reduce salt levels in processed foods. This study aimed to assess trends in salt intake, dietary sources of salt and discretionary salt use in primary schoolchildren pre- and post-delivery of the intervention. DESIGN: Repeated cross-sectional surveys were completed at baseline (2010-2013) and follow-up (2018-2019). Salt intake was measured via 24-h urinary Na excretion, discretionary salt use behaviours by self-report and sources of salt by 24-h dietary recall. Data were analysed with multivariable-adjusted regression models. SETTING: Victoria, Australia. PARTICIPANTS: Children aged 4-12 years. RESULTS: Complete 24-h urine samples were collected from 666 children at baseline and 161 at follow-up. Mean salt intake remained unchanged from baseline (6·0; se 0·1 g/d) to follow-up (6·1; 0·4 g/d) (P = 0·36), and there were no clear differences in the food sources of salt and at both time points approximately 70 % of children exceeded Na intake recommendations. At follow-up, 14 % more parents (P = 0·001) reported adding salt during cooking, but child use of table salt and inclusion of a saltshaker on the table remained unchanged. CONCLUSION: These findings show no beneficial effect of the Victorian Salt Reduction Partnership intervention on children's salt intake. More intensive, sustained and coordinated efforts between state and federal stakeholders are required.

Impact of growth, gonadal hormones, adiposity and the sodium-to-potassium ratio on longitudinal adolescent measures of blood pressure at puberty.

Blood pressure (BP) rises rapidly at puberty. While this is partly due to normal development, factors like excess adiposity and a high intake of dietary sodium relative to potassium may contribute to a true increase in hypertension risk. This study aimed to assess the relative impact of growth, gonadal hormones, adiposity and the sodium-to-potassium ratio (Na:K) on longitudinal BP measures at puberty. This study analysed data from a three-year longitudinal cohort study of pubertal adolescents. Anthropometry, body composition (bio-electrical impedance), serum testosterone and oestradiol (mass spectrometry) were measured annually. Na:K was measured from three-monthly urine samples. These variables were used to predict annual BP measures using mixed modelling and ordinal regression. Data from 325 adolescents (11.7 ± 1.0 y; 55% male) were analysed, showing typical growth patterns at puberty. Systolic BP increased over time in both sexes (p < 0.01), with boys exhibiting a significantly steeper rise compared to girls. Adiposity variables (BMI z-score, percent body fat, fat mass, waist-to-height ratio) strongly and consistently predicted systolic and diastolic BP in both sexes (all p < 0.05). Systolic BP was also significantly and positively related to height (p < 0.05). No associations with BP were identified in either sex for gonadal hormones or Na:K. Similar results were obtained when BP was classified into hypertension categories. Relative to other developmental and diet-related variables tested, adiposity was found to be the strongest most consistent predictor of BP in pubertal adolescents. Findings highlight the importance of dedicated youth obesity management interventions and policy measures for reducing long-term hypertension and cardiovascular disease risks.Australian New Zealand Clinical Trials Registry ACTRN12617000964314.

The Role of Electroencephalography in the Prognostication of Clinical Outcomes in Critically Ill Children: A Review.

Electroencephalography (EEG) is a neurologic monitoring modality that allows for the identification of seizures and the understanding of cerebral function. Not only can EEG data provide real-time information about a patient's clinical status, but providers are increasingly using these results to understand short and long-term prognosis in critical illnesses. Adult studies have explored these associations for many years, and now the focus has turned to applying these concepts to the pediatric literature. The aim of this review is to characterize how EEG can be utilized clinically in pediatric intensive care settings and to highlight the current data available to understand EEG features in association with functional outcomes in children after critical illness. In the evaluation of seizures and seizure burden in children, there is abundant data to suggest that the presence of status epilepticus during illness is associated with poorer outcomes and a higher risk of mortality. There is also emerging evidence indicating that poorly organized EEG backgrounds, lack of normal sleep features and lack of electrographic reactivity to clinical exams portend worse outcomes in this population. Prognostication in pediatric critical illness must be informed by the comprehensive evaluation of a patient's clinical status but the utilization of EEG may help contribute to this assessment in a meaningful way.

Predicting metabolizable energy from digestible energy for growing and finishing beef cattle and relationships to the prediction of methane.

Reliable predictions of metabolizable energy (ME) from digestible energy (DE) are necessary to prescribe nutrient requirements of beef cattle accurately. A previously developed database that included 87 treatment means from 23 respiration calorimetry studies has been updated to evaluate the efficiency of converting DE to ME by adding 47 treatment means from 11 additional studies. Diets were fed to growing-finishing cattle under individual feeding conditions. A citation-adjusted linear regression equation was developed where dietary ME concentration (Mcal/kg of dry matter [DM]) was the dependent variable and dietary DE concentration (Mcal/kg) was the independent variable: ME = 1.0001 × DE - 0.3926; r2 = 0.99, root mean square prediction error [RMSPE] = 0.04, and P < 0.01 for the intercept and slope. The slope did not differ from unity (95% CI = 0.936 to 1.065); therefore, the intercept (95% CI = -0.567 to -0.218) defines the value of ME predicted from DE. For practical use, we recommend ME = DE - 0.39. Based on the relationship between DE and ME, we calculated the citation-adjusted loss of methane, which yielded a value of 0.2433 Mcal/kg of dry matter intake (DMI; SE = 0.0134). This value was also adjusted for the effects of DMI above maintenance, yielding a citation-adjusted relationship: CH4, Mcal/kg = 0.3344 - 0.05639 × multiple of maintenance; r2 = 0.536, RMSPE = 0.0245, and P < 0.01 for the intercept and slope. Both the 0.2433 value and the result of the intake-adjusted equation can be multiplied by DMI to yield an estimate of methane production. These two approaches were evaluated using a second, independent database comprising 129 data points from 29 published studies. Four equations in the literature that used DMI or intake energy to predict methane production also were evaluated with the second database. The mean bias was substantially greater for the two new equations, but slope bias was substantially less than noted for the other DMI-based equations. Our results suggest that ME for growing and finishing cattle can be predicted from DE across a wide range of diets, cattle types, and intake levels by simply subtracting a constant from DE. Mean bias associated with our two new methane emission equations suggests that further research is needed to determine whether coefficients to predict methane from DMI could be developed for specific diet types, levels of DMI relative to body weight, or other variables that affect the emission of methane.

Food sources of iodine in schoolchildren and relationship with 24-h urinary iodine excretion in Victoria, Australia.

Dietary recalls have been used previously to identify food sources of iodine in Australian schoolchildren. Dietary assessment can provide information on the relative contributions of individual food groups which can be related to a robust objective measure of daily intake (24-h urinary iodine excretion (UIE)). In Australia, the government has mandated the use of iodised salt in breadmaking to address iodine deficiency. The aim of this study was to determine the dietary intake and food sources of iodine to assess their contribution to iodine excretion (UIE) in a sample of Australian schoolchildren. In 2011-2013, UIE was assessed using a single 24-h urine sample and dietary intake was assessed using one 24-h dietary recall in a convenience sample of primary schoolchildren from schools in Victoria, Australia. Of the 454 children with a valid recall and urine sample, 55 % were male (average age 10·1 (1·3 (sd) years). Mean UIE and dietary iodine intake were 108 (sd 54) and 172 (sd 74) µg/d, respectively. Dietary assessment indicated that bread and milk were the main food sources of iodine, contributing 27 and 25 %, respectively, to dietary iodine. Milk but not bread intake was positively associated with UIE. Multiple regression (adjusted for school cluster, age and sex) indicated that for every 100 g increase in milk consumption, there was a 3 µg/d increase in UIE (ß = 4·0 (se 0·9), P < 0·001). In conclusion, both bread and milk were important contributors to dietary iodine intake; however, consumption of bread was not associated with daily iodine excretion in this group of Australian schoolchildren.

Head Trauma not Associated with Long Term Effects on Autonomic Function.

Contact-sports can elicit concussions, which impacts autonomic function, as well as elicit repetitive head trauma, where autonomic function has not yet been assessed. The purpose of this study was to determine if differences in autonomic function exist among three groups (CTRL: healthy non-contact-sport participant, RHT: repetitive head trauma contact-sport participant, CONC: previous concussion). Forty participants (16 men and 24 women), aged 18-37 (22 ± 3), participated in the study. Participants were grouped based on their sport and concussion history (CTRL, RHT, and CONC). Body composition was measured via air displacement plethysmography. Prior to testing, participants were outfitted with equipment to evaluate heart rate, blood pressure, and cerebral-artery blood flow velocity (CBFv). The participant performed against three stimuli: deep breathing, Valsalva maneuver, and a 70° head-up tilt test. Following autonomic function testing, a YMCA submaximal cycle test was performed. All group comparisons were analyzed using a one-way ANOVA and all data are presented as means ± standard deviation. The results of this study indicated that the groups did not differ in respiratory sinus arrhythmia (CTRL: 22 ± 6 bpm, RHT: 21 ± 8 bpm, CONC: 19 ± 7 bpm, p = 0.471), Valsalva ratio (CTRL: 2.19 ± 0.39, RHT: 2.09 ± 0.37, CONC: 2.00 ± 0.47, p = 0.519), CBFv (CTRL: 47.74 ± 25.28 cm/s, RHT: 40.99 ± 10.93 cm/s, CONC: 43.97 ± 17.55 cm/s, p = 0.657), or tilt time (CTRL: 806.09 ± 368.37 sec, RHT: 943.07 ± 339.54 sec, CONC: 978.40 ± 387.98 sec, p = 0.479). However, CONC (113.24 ± 11.64 mmHg) had a significantly higher mean systolic blood pressure during the tilt test than CTRL (102.66 ± 7.79 mmHg, p = 0.026), while RHT (107.9 ± 9.0 mmHg) was not significantly different than CTRL (p = 0.39) or CONC (p = 0.319). The results of this study are the first step in determining if long-lasting deficits to the autonomic nervous system occur following a diagnosis of concussion. However, concussions do not seem to have lasting effects on autonomic function. Overwhelmingly, dysautonomia is not present during chronic recovery from concussions or in individuals with RHT from contact-sports. In the future, sex should be considered as a variable.

Shaft-only Phalloplasty: Technical Modifications to Optimize Aesthetics.

Shaft-only phalloplasty (SOP) has been described as an alternative option for phalloplasty. Although traditional phalloplasty represents the most complete form of genital gender-affirming surgery, this variation also carries the greatest surgical risk. Patients may opt for a lower risk SOP for reasons including gender identity, gender expression, sexual function, desire for future childbearing, or minimal gender dysphoria associated with sedentary urination. Further, some patients may, due to associated co-morbidities, not be a candidate for neourethral reconstruction. Forgoing urethral reconstruction also means forgoing the presence of a distal urethral meatus and thereby compromising on one of the basic tenets of phalloplasty surgery-the aesthetic appearance. In an SOP, the flap is usually a simple tube with a purse-string suture placed at the distal end. Another concern can be the insufficient bulk of the phallus due to the absence of the volume added by the inner tube. The purpose of this article is to review our technical modifications that allow for creation of a phallic meatus as well as increasing phallic girth when needed. The most frequently described technique to create a neo-urethra is the tube-within-tube concept. We expanded on this and apply it as a short segment for distal meatal creation in an SOP. Improved aesthetics are achieved by creating the appearance of a phallic meatus and when desired, utilizing a lateral de-epithelialized strip to increase phallic bulk and girth. We hope these technical refinements can assist the surgeon in better meeting the goal of creating an aesthetically pleasing phallus.

The association between dietary sodium intake, adiposity and sugar-sweetened beverages in children and adults: a systematic review and meta-analysis.

Higher intakes of Na may contribute to weight gain. The primary aim of this systematic review and meta-analysis was to examine the relationship between dietary Na intake and measures of adiposity in children and adults. Given the previous link between Na intake and the consumption of sugar-sweetened beverages (SSB), which are a known risk factor for obesity, a secondary aim examining the relationship between Na intake and SSB consumption was assessed. A systematic literature search identified cross-sectional and longitudinal studies and randomised controlled trials (RCT) which reduced dietary Na (≥3 months). Meta-analysis was performed for outcomes with ≥3 studies. Cross-sectionally higher Na intakes were associated with overweight/obesity in adults (five studies; n 11 067; OR 1·74; 95 % CI 1·43, 2·13) and in children (three studies; n 3625, OR 3·29; 95 % CI 2·25, 4·80), and abdominal obesity (five studies; n 19 744; OR 2·04; 95 % CI 1·72, 2·42) in adults. Overall, associations remained in sensitivity analyses which adjusted for energy. Findings from longitudinal studies were inconsistent. RCT in adults indicated a trend for lower body weight on reduced-Na compared with control diets (fifteen studies; n 5274; -0·29 kg; 95 % CI -0·59, 0·01; P = 0·06); however, it is unclear if energy intakes were also altered on reduced-Na diets. Among children higher Na intakes were associated with higher intake of SSB (four studies, n 10 329, b = 22, 16 and 26 g/d); no studies were retrieved for adults. Overall, there was a lack of high-quality studies retrieved. While cross-sectional evidence indicates Na intake was positively associated with adiposity, these findings have not been clearly confirmed by longitudinal studies or RCT.

Salt-Related Knowledge, Attitudes and Behaviors (KABs) among Victorian Adults Following 22-Months of a Consumer Awareness Campaign.

The Australian population consumes more salt than recommended and this increases the risk of raised blood pressure and cardiovascular disease. In 2015, a state-wide initiative was launched in the Australian state of Victoria to reduce population salt intake. This study examines whether salt-related knowledge, attitudes and behaviors (KABs) of Victorian adults changed following the first 22 months of a consumer awareness campaign targeting parents. Repeated cross-sectional surveys of adults (18-65 years) recruited from research panels. Analyses were weighted to reflect the Victorian population. In both surveys mean age of participants (1584 in 2015 and 2141 in 2018) was 41 years, and 51% were female. This includes 554 parents/caregivers in 2015 and 799 in 2018. Most indicators of KAB remained unchanged. Among parents/caregivers the percentage who agreed limiting salt in their child's diet was important increased by 8% (p = 0.001), and there was a 10% reduction in the percentage who reported placing a saltshaker on the table and a 9% reduction in those who reported their child added salt at the table (both p < 0.001). Some small adverse effects on other indicators were also observed. During the first 22 months of a salt reduction consumer awareness campaign, there were limited changes in KAB overall, however the target audience reported positive changes regarding their children, which aligned with the campaign messages.

A systematic review and meta-analysis of 24-h urinary output of children and adolescents: impact on the assessment of iodine status using urinary biomarkers.

PURPOSE: Urinary iodine concentration (UIC (µg/ml) from spot urine samples collected from school-aged children is used to determine the iodine status of populations. Some studies further extrapolate UIC to represent daily iodine intake, based on the assumption that children pass approximately 1 L urine over 24-h, but this has never been assessed in population studies. Therefore, the present review aimed to collate and produce an estimate of the average 24-h urine volume of children and adolescents (> 1 year and < 19 years) from published studies. METHODS: EBSCOHOST and EMBASE databases were searched to identify studies which reported the mean 24-h urinary volume of healthy children (> 1 year and < 19 years). The overall mean (95% CI) estimate of 24-h urine volume was determined using a random effects model, broken down by age group. RESULTS: Of the 44 studies identified, a meta-analysis of 27 studies, with at least one criterion for assessing the completeness of urine collections, indicated that the mean urine volume of 2-19 year olds was 773 (654, 893) (95% CI) mL/24-h. When broken down by age group, mean (95% CI) 24-h urine volume was 531 mL/day (454, 607) for 2-5 year olds, 771 mL/day (734, 808) for 6-12 year olds, and 1067 mL/day (855, 1279) for 13-19 year olds. CONCLUSIONS: These results demonstrate that the average urine volume of children aged 2-12 years is less than 1 L, therefore, misclassification of iodine intakes may occur when urine volumes fall below or above 1 L. Future studies utilizing spot urine samples to assess iodine status should consider this when extrapolating UIC to represent iodine intakes of a population.