Growth and growth hormone treatment in children with chronic diseases

Growth hormone treatment in pre-pubertal short Chinese children with chronic kidney disease prior to transplantation

BACKGROUND

The effect of recombinant human GH (rhGH) in Chinese children with chronic kidney disease (CKD) is unclear.

METHODS

This was a 52-week, multicenter, randomized, open-label, negative-controlled phase 3 study. Prepubertal subjects were randomized 1:1 to either daily subcutaneous injections of rhGH 0.05 mg/kg/day or no treatment for 52 weeks.

RESULTS

A total of 68 subjects with a mean age of 7.8 ± 3.27 years were enrolled. At week 52, the height standard deviation score (HT-SDS) in the treated group increased by 0.75 ± 0.58, which was significantly higher compared with 0.17 ± 0.47 in the untreated group (least squares mean 0.58, 95% confidence interval, 0.32-0.84; P < 0.001). At week 52, significant improvements were observed in other growth parameters (height velocity [P < 0.001]), insulin-like growth factor 1 (IGF-1) SDS [P < 0.001], IFG-1/insulin-like growth factor binding protein-3 molar ratio [P < 0.001], and height [P < 0.001]) compared with the untreated control. Seven patients reported treatment-related adverse events (TRAEs) and most TRAEs were mild in severity. Most subjects recovered without further intervention.

CONCLUSIONS

Daily rhGH for 52 weeks in children with CKD-induced growth retardation significantly improved HT-SDS and other growth parameters without compromising safety.

IMPACT

The efficacy and safety of growth hormone (GH) therapy in Chinese children with chronic kidney disease (CKD) are unclear. This study found that giving short stature Chinese children with CKD daily recombinant human growth hormone (rhGH) for 52 weeks improved growth parameters without compromising safety. This study's information can give physicians the confidence to treat these patients in their clinical practice.

Growth Hormone Deficiency and Lysinuric Protein Intolerance: Case Report and Review of the Literature

BACKGROUND

Lysinuric protein intolerance (LPI; MIM# 222700) is a rare metabolic disorder caused by a defective cationic amino acids (CAA) membrane transport leading to decreased circulating plasma CAA levels and resulting in dysfunction of the urea cycle. Short stature is commonly observed in children with LPI and has been associated with protein malnutrition. A correlation between LPI and growth hormone deficiency (GHD) has also been postulated because of the known interaction between the AA arginine, ornithine, and lysine and growth hormone (GH) secretion. Our report describes a case of GHD in an LPI patient, who has not presented a significant increase in growth velocity with recombinant-human GH (rhGH) therapy, suggesting some possible pathogenic mechanisms of growth failure.

CASE PRESENTATION

The proband was a 6-year-old boy, diagnosed as suffering from LPI, erythrophagocytosis (HP) in bone marrow, and short stature. Two GH provocative tests revealed GHD. The patient started rhGH therapy and a controlled-protein diet initially with supplementation of oral arginine and then of citrulline. At 3-year follow-up, no significant increase in growth velocity and in insulin-like growth factor-1 (IGF-1) levels was observed. Inadequate nutrition and low plasmatic levels of arginine, ornithine, lysine, and HP may have contributed to his poor growth.

CONCLUSION

Our case suggests that growth failure in patients with GHD and LPI treated with rhGH could have a complex and multifactorial pathogenesis. Persistently low plasmatic levels of lysine, arginine, and ornithine, associated with dietary protein and caloric restriction and systemic inflammation, could determine a defect in coupling GH to IGF-1 production explaining why GH replacement therapy is not able to significantly improve growth impairment. We hypothesize that a better understanding of growth failure pathophysiology in these patients could lead to the development of more rational strategies to treat short stature in patients with LPI.

Growth retardation and growth hormone deficiency in patients with Ataxia telangiectasia

BACKGROUND

Ataxia telangiectasia (A-T) is a devastating human recessive disorder characterised by progressive cerebellar ataxia, immunodeficiency, genetic instability, and cancer susceptibility. In addition, many patients suffer from growth failure.

METHODS

We analyzed growth and IGF-1/BP3 levels of 24 A-T-patients compared with an age-matched group of healthy controls (n = 36).

RESULTS

Ten (41.7%) A-T patients and none of healthy controls had an IGF-1 level below the 3rd percentile for age. The growth hormone (GH) stimulation tests revealed a severe GH deficiency with no increase of >5 ng/ml in six of the ten A-T patients. The IGF-1 generation tests revealed normal increases in IGF-1 values in all patients.

CONCLUSION

Our results show that a disturbance in the GH/IGF-1 axis was present in 58.3% of A-T patients. Low levels of GH were the result of reduced central GH secretion. GH treatment may be a therapeutic option for A-T patients with severe growth failure.

Interaction of the endocrine system with inflammation: a function of energy and volume regulation

During acute systemic infectious disease, precisely regulated release of energy-rich substrates (glucose, free fatty acids, and amino acids) and auxiliary elements such as calcium/phosphorus from storage sites (fat tissue, muscle, liver, and bone) are highly important because these factors are needed by an energy-consuming immune system in a situation with little or no food/water intake (sickness behavior). This positively selected program for short-lived infectious diseases is similarly applied during chronic inflammatory diseases. This review presents the interaction of hormones and inflammation by focusing on energy storage/expenditure and volume regulation. Energy storage hormones are represented by insulin (glucose/lipid storage and growth-related processes), insulin-like growth factor-1 (IGF-1) (muscle and bone growth), androgens (muscle and bone growth), vitamin D (bone growth), and osteocalcin (bone growth, support of insulin, and testosterone). Energy expenditure hormones are represented by cortisol (breakdown of liver glycogen/adipose tissue triglycerides/muscle protein, and gluconeogenesis; water retention), noradrenaline/adrenaline (breakdown of liver glycogen/adipose tissue triglycerides, and gluconeogenesis; water retention), growth hormone (glucogenic, lipolytic; has also growth-related aspects; water retention), thyroid gland hormones (increase metabolic effects of adrenaline/noradrenaline), and angiotensin II (induce insulin resistance and retain water). In chronic inflammatory diseases, a preponderance of energy expenditure pathways is switched on, leading to typical hormonal changes such as insulin/IGF-1 resistance, hypoandrogenemia, hypovitaminosis D, mild hypercortisolemia, and increased activity of the sympathetic nervous system and the renin-angiotensin-aldosterone system. Though necessary during acute inflammation in the context of systemic infection or trauma, these long-standing changes contribute to increased mortality in chronic inflammatory diseases.