Establishing Normal Ranges of Basal and ACTH-Stimulated Serum Free Cortisol in Children

Overdiagnosis of adrenal insufficiency in children with biliary atresia

Serum cortisol mainly binds to the cortisol-binding globulin (CBG). Children with biliary atresia (BA) may have low serum CBG levels; thus, low serum total cortisol (TC) levels and adrenal insufficiency (AI) may be overdiagnosed. This study aimed to assess adrenal function in children with BA. All the patients underwent adrenocorticotropic hormone (ACTH) stimulation tests. Plasma ACTH, serum TC, and CBG levels were measured at baseline, with additional TC measurements at 30 and 60 min during testing. Free cortisol (FC) index (FCI) and calculated FC (cFC) were also calculated. AI was defined as peak TC <500 nmol/L (<18 μg/dL), peak FCI <12 nmol/mg, or peak cFC <33 nmol/L (<1.2 μg/dL). This study enrolled 71 children with BA. The Median (IQR) age of the patients was 5.5 (1.7-11.4) years. Twenty-five (35%) patients were diagnosed with AI based on the peak TC. In the AI group, the median serum CBG level was significantly lower than that in the non-AI group (481 vs. 533 nmol/L, p = 0.03). Only eight patients (11%) met all three AI criteria (six secondary AI and two primary AI). In conclusion, low serum CBG levels contribute to reduced peak TC and, consequently, overdiagnosing AI. Peak FCI and cFC could help reduce the overdiagnosis of AI.

Central adrenal insufficiency screening with morning plasma cortisol and ACTH levels in Prader-Willi syndrome

OBJECTIVES

Prader-Willi syndrome (PWS) is a complex genetic disorder with severe hypotonia, failure to thrive, childhood obesity, hypogonadism/hypogenitalism and learning/behavioral problems with endocrine-related growth and other hormone deficiencies. The prevalence of central adrenal insufficiency (CAI) using dynamic testing ranges from rare to 60%. We compared routine morning plasma cortisol (MPC) and ACTH levels in large cohorts of PWS and control children to address CAI.

METHODS

Retrospective analysis of MPC and ACTH levels was undertaken in 128 PWS growth hormone (GH)-treated children under medical care before considering dynamic testing for CAI and 128 non-syndromic control children with short stature evaluated for GH deficiency.

RESULTS

The average MPC level in PWS was 9.7 ± 3.7 μg/dL with no difference in age, gender or PWS genetic subtype and 13.4 ± 5.7 μg/dL in the control group. MPC levels were significantly lower (p < 0.05) in PWS but in the normal range. The morning plasma ACTH level in the PWS group was 22.1 ± 8.0 pg/mL with one individual having an initial low plasma ACTH level (8 pg/mL), but normal upon repeat.

CONCLUSIONS

MPC levels in PWS are normal and comparable with control children, without evidence or increased risk of CAI. Lower but normal MPC levels were seen in PWS and suggestive of reduced local regeneration of cortisol from cortisone in adipose tissue by the GH-IGF-I system. Hence, MPC measures alone or in combination with ACTH should be considered for initial screening for CAI in PWS but prior to dynamic testing.

Cortisol Levels During Acute Illnesses in Children and Adolescents: A Systematic Review

Importance

Endogenous cortisol levels in children and adolescents during acute illnesses can contribute to the evidence base required to optimize glucocorticoid (GC) stress doses for children and adolescents known to have GC deficiency.

Objective

To identify endogenous cortisol levels during a range of acute illnesses in children and adolescents without GC deficiency from published evidence.

Evidence Review

CINAHL, Cochrane Library, Cochrane Database of Systematic Reviews, Embase, and MEDLINE were searched for studies published between January 1, 2000, and June 30, 2020. Two reviewers independently identified relevant studies. Differences were resolved by joint discussion. Inclusion criteria were common acute illnesses, age from 1 month to 18 years, and basal blood cortisol levels obtained within 48 hours of presentation. Studies with fewer than 5 participants and those that included participants known to have GC deficiency or a history of treatment that could affect cortisol levels were excluded from the review. Data for predefined fields were extracted and independently checked by separate pairs of reviewers. Overall weighted means and pooled SDs for cortisol levels were calculated.

Findings

All 15 studies included were hospital based and included 864 unique participants: 14 studies were prospective observational studies, 1 was part of a trial, and 5 included control individuals. Mean cortisol levels were higher in all participants with an acute illness (n = 689) than in controls (n = 175) (difference in weighted means, 18.95 μg/dL; 95% CI, 16.68-21.22 μg/dL). Cortisol levels were highest in patients with bacterial meningitis (weighted mean [pooled SD], 46.42 [22.24] μg/dL) and were more than 3-fold higher in the group with severe gastroenteritis (weighted mean [pooled SD], 39.64 [21.34] μg/dL) than in the control group. Among the subgroups with sepsis, those with shock had lower cortisol levels than those without shock (weighted mean [pooled SD], 27.83 [36.39] μg/dL vs 37.00 [23.30] μg/dL), but levels in nonsurvivors did not differ from levels in survivors (weighted mean [pooled SD], 24.89 [51.65] μg/dL vs 30.53 [30.60] μg/dL).

Conclusions and Relevance

This systematic review found that, in children and adolescents without GC deficiency, circulating cortisol levels were higher during acute illnesses than those in controls and also varied across a range of acute illnesses. Whether these levels need to be achieved with exogenous GC stress doses tailored according to the nature and severity of the illness in children and adolescents with GC deficiency warrants investigation.

How to interpret a single cortisol measurement

Adrenal insufficiency can present with non-specific clinical features. Therefore, a single cortisol measurement is often included in the biochemical work-up of an unwell child. This article aims to review the diagnostic utility of a single cortisol measurement by outlining the physiological, clinical and technical factors affecting result interpretation. Clinical scenarios are used to illustrate how this test may be used in different commonly encountered situations in general paediatrics, with the aim of minimising the frequency of inconclusive results.

Salivary aldosterone and cortisone respond differently to high- and low-psychologically stressful soccer competitions

Aldosterone and cortisone are released in response to physical and psychological stress. However, aldosterone and cortisone responses in children engaged in physical competition have not been described. We examined salivary aldosterone and salivary cortisone responses among Hong Kongese boys, aged 8-11 years, during (1) a soccer match against unknown competitors (N = 84, high psychological stress condition) and (2) an intrasquad soccer scrimmage against teammates (N = 81, low psychological stress condition). Aldosterone levels increased during the soccer match and intrasquad soccer scrimmage conditions, consistent with the view that aldosterone responds to physical stress. During the soccer match, winning competitors experienced larger increases in aldosterone compared to losing competitors, indicating that the degree of aldosterone increase was attenuated by match outcome. Cortisone increased during the soccer match and decreased during the intrasquad soccer scrimmage. Competitors on teams that resulted in a tie had larger cortisone increases compared to winners or losers. These findings highlight that the degree of cortisone change is related to boy's cognitive appraisal of the competitor type (i.e., teammates vs. unknown competitors) and the competitive nature of the game (e.g., tie). These results shed new light on adrenal hormone mediators of stress and competition during middle childhood.

Reference values for salivary cortisol in healthy young infants by liquid chromatography-tandem mass spectrometry

BACKGROUND

Sampling of salivary cortisol is non-invasive and important for the evaluation of the hypothalamic-pituitary-adrenal axis function and stress levels. However, the reference values for salivary cortisol measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in healthy infants are unclear. The aim of this study was to establish the reference values for salivary cortisol levels in healthy infants.

METHODS

This study was a prospective observational cohort study following the participants until the age of 6 months. We analyzed 71 healthy, full-term infants at age 1 month between December 2017 and March 2018. We repeated saliva sampling every month, measured the salivary cortisol levels in the early morning by LC-MS/MS, and took the subjects' medical history by questionnaire.

RESULTS

The minimum, 25th, 50th, 75th percentile, and maximum salivary cortisol levels were 0.08, 1.11, 2.21, 5.18, and 30.35 nmol/L, respectively.

CONCLUSIONS

We established the reference values for salivary cortisol in young infants using LC-MS/MS.

Mindfulness affects stress, ghrelin, and BMI of obese children: a clinical trial

Childhood obesity is associated with stress. However, most treatment strategies include only dietary and physical activity approaches. Mindfulness may assist in weight reduction, but its effectiveness is unclear. We assessed the effect of mindfulness on stress, appetite regulators, and weight of children with obesity and anxiety. A clinical study was conducted in a pediatric hospital. Eligible children were 10-14 years old, BMI ≥95th percentile, Spence anxiety score ≥55, and who were not taking any medication or supplementation. Participants were assigned to receive an 8-week conventional nutritional intervention (CNI) or an 8-week mindfulness-based intervention plus CNI (MND-CNI). Anthropometry, body composition, leptin, insulin, ghrelin, cortisol, and Spence scores were measured at baseline and at the end of the intervention. Anthropometry was analyzed again 8 weeks after concluding interventions. Log-transformed and delta values were calculated for analysis. Thirty-three MND-CNI and 12 CNI children finished interventions; 17 MND-CNI children accomplished 16 weeks. At the end of the intervention, significant reductions in anxiety score (-6.21 ± 1.10), BMI (-0.45 ± 1.2 kg/m2), body fat (-1.28 ± 0.25%), ghrelin (-0.71 ± 0.37 pg/mL), and serum cortisol (-1.42 ± 0.94 µg/dL) were observed in MND-CNI children. Changes in anxiety score, ghrelin, and cortisol were different between groups (P < 0.05). Children who completed 16 weeks decreased BMI after intervention (-0.944 ± 0.20 kg/m2, P < 0.001) and remained lower 8 weeks later (-0.706 ± 0.19 kg/m2, P = 0.001). We concluded that mindfulness is a promising tool as an adjunctive therapy for childhood obesity. However, our findings need confirmation in a larger sample population.

Adrenal crises in children with adrenal insufficiency: epidemiology and risk factors

The aim of the study was to assess the epidemiology and risk factors of adrenal crises (AC) in children with adrenal insufficiency (AI). Children diagnosed with AI between 1990 and 2017 at four Israeli pediatric endocrinology units were studied. Demographic and clinical data were retrieved retrospectively from their files. The study population consisted of 120 children (73 boys, 47 girls) and comprised 904 patient years. Median age at diagnosis was 0.3 years (0-17.5). Thirty-one AC events in 26 children occurred during the study period, accounting for a frequency of 3.4 crises/100 patient years. Fifty-two percent of AC events occurred at presentation. The significant risk factors for developing AC were the following: younger age at diagnosis (P = 0.003), primary AI vs. secondary AI (P = 0.016), specific diagnosis of autoimmune AI, adrenal hypoplasia congenita and salt wasting congenital adrenal hyperplasia (P < 0.001), mineralocorticoid treatment (P < 0.001), and recurrent hospital admissions (P > 0.001). After applying a stepwise logistic regression model, only the group of diagnoses, including salt wasting CAH, AHC, and Addison's disease, remained significant predictor of AC (OR 17.5, 95% CI 4.7-64.9, P < 0.001). There was no AC-associated mortality during the study period.Conclusions: Since significant percent of AC events occurred at presentation, measures to increase the awareness to signs and symptoms of AI among primary care physicians should be taken. Efforts to prevent AC should be focused on younger patients, especially those with primary AI. What Is Known: • Diagnosis and long-term management of pediatric patients with adrenal insufficiency (AI) remain a challenge. • Adrenal crises (AC) pose life-threatening emergencies in affected youngsters. Studies on the rate and risk factors of AC in children with AI are scarce, and they were done mainly on children with congenital adrenal hyperplasia (CAH). What Is New: • The rate of AC was relatively low and there was no AC-associated mortality during the study period. • Children with primary AI were at higher risk for AC than children with secondary AI. Specifically, children with salt wasting CAH, adrenal hypoplasia congenita, and Addison's disease at the highest risk.

Adrenoleukodystrophy: Guidance for Adrenal Surveillance in Males Identified by Newborn Screen

CONTEXT

Adrenoleukodystrophy (ALD) is a peroxisomal disorder associated with neurologic decompensation and adrenal insufficiency. Newborn screening for ALD has recently been implemented in five states with plans to expand to all 50 states in the United States. Adrenal insufficiency ultimately develops in most males with ALD, but the earliest age of onset is not well established.

OBJECTIVE

These clinical recommendations are intended to address screening for adrenal insufficiency in boys identified to have ALD by newborn screen.

PARTICIPANTS

Seven members of the Pediatric Endocrine Society Drug and Therapeutics/Rare Diseases Committee, with clinical experience treating children with ALD and adrenal insufficiency, and a pediatric endocrinologist and laboratory director were selected to be on the working committee.

CONSENSUS PROCESS

The authors comprised the working group and performed systematic reviews of the published literature regarding adrenal insufficiency and ALD. The recommendations were reviewed and approved by the larger Pediatric Endocrine Society Drug and Therapeutics/Rare Diseases Committee and then by the Pediatric Endocrine Society Board of Directors.

CONCLUSIONS

There is limited literature evidence regarding monitoring of evolving adrenal insufficiency in male infants and children with ALD. The recommendations suggest initiating assessment of adrenal function at diagnosis with ALD and regular monitoring to identify boys with adrenal insufficiency in a timely manner and prevent life-threatening adrenal crisis. These recommendations are intended to serve as an initial guide, with the understanding that additional experience will inform future guidelines.

SERUM FREE CORTISOL DURING GLUCAGON STIMULATION TEST IN HEALTHY SHORT-STATURED CHILDREN AND ADOLESCENTS

OBJECTIVE

The total cortisol (TC) response may be measured during the glucagon stimulation test (GST) for growth hormone (GH) reserve in order to assess the integrity of the hypothalamic-pituitary-adrenal (HPA) axis. Measurements of TC are unreliable in conditions of albumin and cortisol-binding globulin (CBG) alterations (e.g., hypoproteinemia or CBG deficiency). We aimed to measure the serum free cortisol (sFC) response to the GST in children and adolescents and determine whether it could predict the GH response to glucagon stimulation.

METHODS

Infants and children with either short stature or growth attenuation who were referred for evaluation of GH reserve underwent the GST.

RESULTS

The study population consisted of 103 subjects (62 females), median age 3.9 years (range, 0.5-14). The mean basal and peak TC levels were 13.3 ± 6.7 μg/dL and 29.6 ± 8.8 μg/dL, respectively. The mean basal and peak sFC levels were 0.7 ± 0.8 μg/dL and 1.7 ± 1.1 μg/dL, respectively. There was a negative correlation between peak TC and age ( r = -0.3, P = .007) but not between peak sFC and age ( r = -0.09, P = .36). Ninety-five percent of the patients had peak TC levels >15.8 μg/dL and peak sFC levels >0.6 μg/dL.

CONCLUSION

Our results on a cohort of healthy short-statured children can serve as reference values for the sFC response during GST. Based on these results, we propose peak TC levels >15.8 μg/dL and peak sFC levels >0.6 μg/dL for defining normalcy of the HPA axis during the GST in children and adolescents.

ABBREVIATIONS

ACTH = adrenocorticotrophic hormone BMI = body mass index CBG = cortisol-binding globulin GH = growth hormone GST = glucagon stimulation test HPA = hypothalamic-pituitary-adrenal SDS = standard deviation score sFC = serum free cortisol TC = total cortisol.

The role of corticosteroid-binding globulin in the evaluation of adrenal insufficiency

Cortisol is a hydrophobic molecule that is largely bound to corticosteroid-binding globulin (CBG) in the circulation. In the assessment of adrenal insufficiency, many clinicians measure a total serum cortisol level, which assumes that CBG is present in normal concentrations and with a normal binding affinity for cortisol. CBG concentration and affinity are affected by a number of common factors including oral contraceptive pills (OCPs), fever and infection, as well as rare mutations in the serine protease inhibitor A6 (SERPINA6) gene, and as such, total cortisol levels might not be the ideal way to assess adrenal function in all clinical circumstances. This paper reviews the limitations of immunoassay and liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the measurement of total cortisol, the challenges of measuring free serum cortisol directly as well as the difficulties in calculating an estimated free cortisol from total cortisol, CBG and albumin concentrations. Newer approaches to the evaluation of adrenal insufficiency, including the measurement of cortisol and cortisone in the saliva, are discussed and a possible future role for these tests is proposed.