John Fielding Crigler, Jr, MD (1919-2018)
Joseph A. Majzoub Chair, Thomas Carpenter, Joseph I. Wolfsdorf
Ref: Ped. Endocrinol. Rev. 2019;17(1):2-3
Emerging Mechanisms of GH-Induced Lipolysis and Insulin Resistance
Vishva M. Sharma, PhD
Growth hormone (GH) is a pleiotropic hormone that coordinates an array of physiological processes including growth and metabolism. GH promotes anabolic action in all tissues except adipose, where it catabolizes stored fat to release energy for the promotion
of growth in other tissues. However, chronic stimulation of lipolysis by GH results in an increased flux of free fatty
acids (FFAs) into systemic circulation. Hence, a sustained release of high levels of GH contributes significantly to
the development of insulin resistance by antagonizing the anti-lipolytic action of insulin. The molecular pathways associated with the lipolytic effect of GH in adipose tissue however, remain elusive. Recent studies have provided molecular insights into GH-induced lipolysis and impairment of insulin signaling. This review discusses the physiological and metabolic actions of GH on adipose tissue as well as GH-mediated deregulation of the FSP27-PPARγ axis which alters adipose tissue homeostasis and contributes to the development of insulin resistance and Type 2 diabetes.
Ref: Ped. Endocrinol. Rev. 2019;17(1):4-16
Key words: Growth hormone, PPARγ, FSP27, CIDEC, Lipid droplets, AKT, Insulin resistance, Fat metabolism, Metabolic
disease, Type 2 diabetes
FGF23 and Associated Disorders of Phosphate Wasting
Anisha Gohil, DO, Erik A. Imel, MD
Fibroblast growth factor 23 (FGF23), one of the endocrine fibroblast growth factors, is a principal regulator in the maintenance of serum phosphorus concentration. Binding to its cofactor αKlotho and a fibroblast growth factor receptor is essential for its
activity. Its regulation and interaction with other factors in the bone-parathyroid-kidney axis is complex. FGF23
reduces serum phosphorus concentration through decreased reabsorption of phosphorus in the kidney and by decreasing
1,25 dihydroxyvitamin D (1,25(OH)2D) concentrations. Various FGF23-mediated disorders of renal phosphate
wasting share similar clinical and biochemical features. The most common of these is X-linked hypophosphatemia (XLH).
Additional disorders of FGF23 excess include autosomal dominant hypophosphatemic rickets, autosomal recessive
hypophosphatemic rickets, fibrous dysplasia, and tumorinduced osteomalacia. Treatment is challenging, requiring
careful monitoring and titration of dosages to optimize effectiveness and to balance side effects. Conventional
therapy for XLH and other disorders of FGF23-mediated hypophosphatemia involves multiple daily doses of oral
phosphate salts and active vitamin D analogs, such as calcitriol or alfacalcidol. Additional treatments may be used to help address side effects of conventional therapy such as thiazides to address hypercalciuria or nephrocalcinosis, and calcimimetics to manage
hyperparathyroidism. The recent development and approval of an anti-FGF23 antibody, burosumab, for use in XLH
provides a novel treatment option.
Ref: Ped. Endocrinol. Rev. 2019;17(1):17-34
Key words: FGF23, klotho, phosphorus, 1,25(OH)2D, XLH, Burosumab, rickets
Are We Aware that Hyperphosphatemia Affects Mortality and Morbidity as much as Hypophosphatemia in Pediatric
Intensive Care Patients?
Yılmaz Akbaş, MD, Alper Koker, MD, Nilgün Erkek, MD
Hypophosphatemia was previously shown to affect the duration of admission, mechanical ventilator requirements, mortality and morbidity
during pediatric intensive care. Different from previous studies, our study was planned with the aim of showing
whether hyperphosphatemia affects morbidity and mortality in pediatric intensive care patients as much as hypophosphatemia.
Patients’ ages, genders, reason for admission, underlying diseases, phosphorus levels examined on admission and
on the 1-4th and 5-10th-days, duration on mechanical ventilation, duration of admission, final status and PRISM
and PELOD scores calculated in the first 24 hours of admission were recorded.
Mortality was distinctly higher for those who were hypophosphatemic and hyperphosphatemic compared to those who were normophosphatemic. The highest mortality was identified in those who were hyperphosphatemic on the 5-10th-days. PELOD scores were only significantly different according to admission phosphorus levels (p:0.04).
In our study, we identified that hyperphosphatemia is a serious problem as hypophosphatemia for patients who admitted to the PICU. Patients identified to be hyperphosphatemic on admission had a significantly higher PELOD score. The significant difference of
hyperphosphatemia in terms of PELOD score is one of the important points shown in our study. It should not be
forgotten that like hypophosphatemia, hyperphosphatemia may cause serious problems in pediatric intensive care
Ref: Ped. Endocrinol. Rev. 2019;17(1):35-40
Key words: Pediatric intensive care, Hyperphosphatemia, Hypophosphatemia, PELOD, Mortality
Growth Hormone Deficiency and Excessive Sleepiness: A Case Report and Review of the
Anisha Gohil, DO, Erica Eugster, MD
The somatotropic axis is intricately involved in normal sleep, as evidenced by the fact that hypothalamic growth hormone-releasing hormone (GHRH) has sleep promoting effects and pituitary growth hormone (GH) release is strongly associated with slow-wave sleep
(SWS). Abnormalities in the somatotropic axis, such as GH deficiency of hypothalamic or pituitary origin, result in an
alteration of normal sleep patterns which may explain the fatigue reported in these individuals. Sleep disorders such
as narcolepsy, in which individuals abnormally enter rapid eye movement (REM) sleep at sleep onset are also associated
with an altered GHRH circadian rhythm and abnormal GH secretion. While few studies are available, this review
explores what is known about sleep abnormalities in GH deficiency, the effect of treatment on sleep in patients with
GH deficiency, and GH secretion in narcolepsy. Emerging evidence suggests a hypothalamic link between narcolepsy
and GH secretion. We also describe the unique constellation of isolated idiopathic GH deficiency and severe excessive
sleepiness in adopted Nicaraguan siblings, one of which has narcolepsy and the other idiopathic hypersomnia.
Ref: Ped. Endocrinol. Rev. 2019;17(1):41-46
Key words: Growth Hormone Deficiency, Narcolepsy, Idiopathic Hypersomnia, Slow-wave Sleep
Letters to the Editors: Central Nervous System Complications in Diabetic Ketoacidosis
Marta Baszyńska-Wilk, MD, Marta Wysocka–Mincewicz, MD, PhD, Małgorzata, Wajda–Cuszlag, MD, Anna Świercz, MD, Mieczysław Szalecki, MD, PhD
Ref: Ped. Endocrinol. Rev. 2019;17(1):47-49
Key words: Neurological complications, Diabetic ketoacidosis, Diabetes type 1
2019 Annual Meeting of the Pediatric Endocrine Society: Selected Highlights
Baltimore, MD (April 26-29, 2019) New Orleans, LA (March 23-26, 2019) Selected Highlights
Danielle Guiffre, MD, Grace Kim, MD, Meenal B. Gupta, MD
Ref: Ped. Endocrinol. Rev. 2019;17(1):50-62
Key words: Hypothyroidism, Thyromimetics, Hypertriglyceridemia, Hyperchylomicronemia, Familial hypercholesterolemia, Mixed dyslipidemia, Turner syndrome