Association of ß-cell function and insulin resistance with pediatric type 2 diabetes among Chinese children.

BACKGROUND: In addition to insulin resistance, impaired insulin secretion has recently been identified as a crucial factor in the pathogenesis of type 2 diabetes mellitus (T2DM). Scarce clinical data exist for pediatric T2DM. AIM: To investigate the association of ß-cell function and insulin resistance with pediatric T2DM in the first Chinese multicenter study. METHODS: This multicenter cross-sectional study included 161 newly diagnosed T2DM children and adolescents between January 2017 and October 2019. Children with normal glycemic levels (n = 1935) were included as healthy control subjects. The homeostasis models (HOMAs) were used to assess the ß-cell function (HOMA2-%B) and insulin resistance (HOMA2-IR) levels. The HOMA index was standardized by sex and age. We performed logistic regression analysis to obtain odds ratios (ORs) for T2DM risk using the standardized HOMA index, adjusted for confounding factors including sex, Tanner stage, T2DM family history, body mass index z-score, and lipid profile. RESULTS: The male-female ratio of newly diagnosed T2DM patients was 1.37:1 (OR = 2.20, P = 0.011), and the mean ages of onset for boys and girls were 12.5 ± 1.9 years and 12.3 ± 1.7 years, respectively. The prevalence of related comorbidities including obesity, elevated blood pressure, and dyslipidemia was 58.2%, 53.2%, and 80.0%, respectively. The T2DM group had lower HOMA2-%B levels (P < 0.001) and higher HOMA2-IR levels (P < 0.001) than the control group. Both the decrease in HOMA2-%B z-score (OR = 8.40, 95%CI: 6.40-11.02, P < 0.001) and the increase in HOMA2-IR z-score (OR = 1.79, 95%CI: 1.60-2.02, P < 0.001) were associated with a higher risk of T2DM, and the decrease in HOMA2-%B z-score always had higher ORs than the increase in HOMA2-IR z-score after adjusting for confounding factors. CONCLUSION: Besides insulin resistance, ß-cell function impairment is also strongly associated with Chinese pediatric T2DM. Gender difference in susceptibility and high comorbidities warrant specific T2DM screening and prevention strategies in Chinese children.

Altered Serum Amino Acid and Acylcarnitine Profiles in Hyperinsulinemic Hypoglycemia and Ketotic Hypoglycemia.

Background: In addition to inborn metabolic disorders, altered metabolic profiles were reported to be associated with the risk and prognosis of some non-metabolic diseases, while as a rare metabolic disease, the overall secondary metabolic spectrum in congenital hyperinsulinemic hypoglycemia (HH) is largely undetermined. Therefore, we investigated metabolic profiles in HH patients and used ketotic hypoglycemia (KH) patients as a control cohort to unveil their distinct metabolic features. Methods: A total of 97 hypoglycemia children, including 74 with hyperinsulinemic hypoglycemia and 23 with ketotic hypoglycemia, and 170 euglycemia control subjects were studied retrospectively. Clinical and biochemical data were collected. The normoglycemic spectra of amino acids and acylcarnitines were determined by liquid chromatography tandem mass spectrometry. The serum insulin and fatty acid concentrations during standardized fasting tests in hypoglycemia patients were also collected. Receiver operating characteristic curve analysis was performed to screen potential biomarkers. Results: Among the normoglycemic spectra of amino acids, blood valine (p < 0.001), arginine (p < 0.001), threonine (p = 0.001), glutamate (p = 0.002), methionine (p = 0.005), ornithine (p = 0.008), leucine (p = 0.014), alanine (p = 0.017), proline (p = 0.031), citrulline (p = 0.042), aspartate (p = 0.046), and glycine (p = 0.048) levels differed significantly among the three groups. Significantly decreased levels of long- (C14:1, p < 0.001; C18, p < 0.001), medium- (C8, p < 0.001; C10, p < 0.001; C10:1, p < 0.001), and short-chain (C4-OH, p < 0.001; C5OH, p < 0.001) acylcarnitines were found in the hyperinsulinemic hypoglycemia group. Hyperinsulinemic hypoglycemia children with focal lesions and diffuse lesions had similar amino acid and acylcarnitine spectra. C10:1 < 0.09 µmol/L, threonine > 35 µmol/L, and threonine/C10:1 > 440 showed sensitivities of 81.1, 66.2, and 81.1% and specificities of 72.7, 78.3, and 81.8%, respectively, in distinguishing HH from KH. Conclusions: We found significantly different altered serum amino acid and acylcarnitine profiles at normoglycemia, especially decreased C10:1 and increased threonine levels, between HH and KH children, which may reflect the insulin ketogenesis inhibition effect in HH patients; however, the detailed mechanisms and physiological roles remain to be studied in the future.

[Association of body fat ratio with precocious puberty in girls].

OBJECTIVE: To study the association of body fat ratio with precocious puberty in girls. Previous studies have shown that body mass index (BMI) is associated with the girls' age of puberty but have not revealed the association of body fat ratio with age of puberty. METHODS: Based on the consensus on the diagnosis and treatment of central precocious puberty (CPP), 128 children with precocious puberty who were admitted to the hospital from July to August, 2017, were divided into a CPP group with 87 children and a peripheral precocious puberty (PPP) group with 41 children. A total of 51 girls without any puberty development signs were enrolled as the control group. Dual-energy X-ray absorptiometry was used to measure the body fat ratios of upper limbs, legs, trunk, android area, gynoid area, and the whole body. The association between body fat ratios and precocious puberty was analyzed with reference to age, BMI, BMI-Z score, bone age, ovarian volume, and hormone levels. RESULTS: Compared with the control group, the CPP and PPP groups had significantly higher body fat ratios of upper limbs, legs, trunk, android area, gynoid area, and the whole body, legs/whole body fat ratio, and (upper limbs+legs)/trunk fat ratio (P<0.05), while there were no significant differences in the above body fat ratios and fat distribution indicators between the CPP and PPP groups (P>0.05). For the girls with precocious puberty, the high body fat ratio group had significantly higher luteinizing hormone (LH) base value, luteinizing hormone releasing hormone (LHRH)-stimulated LH peak value, and LH/follicle-stimulating hormone peak value than the low body fat ratio group (P<0.05). Compared with the control group, both the high body fat ratio and low body fat ratio groups had a significantly higher LH base value (P<0.05). CONCLUSIONS: The increase in body fat may be a factor inducing precocious puberty in girls, but further studies are needed to determine the mechanism.

Clinical characteristics and beta-cell function of Chinese children and adolescents with type 2 diabetes from 2009 to 2018.

BACKGROUND: The limited available studies have unveiled different natural histories and prognosis associated with pediatric type 2 diabetes (T2D) and adult T2D. To date, data on the clinical features, metabolic profiles and beta-cell function characteristics are still limited in the Chinese pediatric T2D population. METHODS: A total of 56 children with T2D, 31 with prediabetes and 159 with obesity were recruited. Clinical characteristics, metabolic profiles, beta-cell function and insulin resistance were analyzed. RESULTS: The mean onset age of T2D was 12.35 ± 1.99 (7.9-17.8) years, and 7% of children were younger than 10 years; 55% of them were male, 57% had a family history of diabetes and 64% had classic symptoms, and 25% had a low or high birth weight. 89% of T2D patients were obese or overweight. A total of 58% of the patients with prediabetes were male. The fast serum C-peptide level was highest in the obesity group (P < 0.001), and there was no significant difference between the T2D and prediabetes groups. The mean homeostatic model of assessment of beta-cell function was the highest in the obesity group and was lowest in the T2D group (P < 0.001). The T2D group had the most serious lipid metabolism disorder, with the highest levels of total triglycerides, total cholesterol, and low density lipoprotein and the lowest high density lipoprotein level among the three groups. CONCLUSIONS: A younger onset age and greater male susceptibility were found in Chinese pediatric T2D patients, and there was a stepwise deterioration trend in beta-cell function among patients with obesity, prediabetes and T2D. Based on our results, together with the SEARCH study results, an early screening and intervention program for T2D is recommended in high-risk or obese Chinese pediatric populations starting at 7 years.

IGF1R Variants in Patients With Growth Impairment: Four Novel Variants and Genotype-Phenotype Correlations.

Objective: IGF1R gene mutations have been associated with varying degrees of intrauterine and postnatal growth retardation, as well as microcephaly. Both autosomal-dominant and autosomal-recessive inheritance patterns have been reported. This study aimed to analyze the IGF1R gene in children with growth impairment using whole-exome sequencing (WES) and assess the clinical features with the autosomal-dominant and autosomal-recessive models. Methods: We performed WES in 28 unrelated patients and found three children harboring IGF1R gene variants. We compared the clinical findings in our cases carrying IGF1R mutations to those in patients reported in the Human Gene Mutation Database (HGMD). Results: We identified four IGF1R gene variations by WES in three unrelated patients, including one missense variant [c.3740T>C (p.M1247T)] (patient 1) inherited from an affected mother, one missense variant [c.744T>G (p.C248W)] (patient 2) inherited from an affected father, and two compound heterozygous variations [c.2305G>C (p.E769Q) and c.2684G>A (p.R895Q)] (patient 3). To date, 22 patients have been described as harboring pathogenic variations in IGF1R in the HGMD. We found that patients with compound heterozygous or homozygous variations displayed more severe phenotypes that were mainly characterized by developmental and speech delays, as well as mental retardation. Conclusion: We identified four pathogenic variations in the IGF1R gene, which expanded the known mutation spectrum. Through a comparison among patients with reported IGF1R pathogenic variations, this study determined that an autosomal-recessive inheritance model of the IGF1R gene may result in a more severe phenotype with developmental and speech delays, as well as mental retardation.

[Recurrent anorexia and pigmentation of skin for more than two months in an infant].

A 2-month-old boy presented with adrenal insufficiency, impaired liver function, hypertriglyceridemia, significantly elevated creatine kinase and electrolyte disturbance. Microarray comparative genomic hybridization (aCGH) analysis test showed a pathogenic 8.7 Mb deletion in the short arm of chromosome X (Xp21.3 - p21.1) and confirmed the diagnosis of complex glycerol kinase deficiency (cGKD). He was treated with hydrocortisone, coenzyme Q10 and L-carnitine and was subsequently followed up for 4 years. His serum cortisol levels returned to normal one week later after treatment, but the serum creatine kinase, triglyceride and aminotransferase levels were progressively increased along with mental retardation and decreased muscular strength. cGKD is also named as Xp21 contiguous gene syndrome. The clinical manifestations of this disease include hypertriglyceridemia, congenital adrenal hypoplasia (AHC), Duchenne muscular dystrophy, and mental retardation. This case highlights the necessity to screen the serum triglyceride and creatine kinase levels in infants with suspected adrenal insufficiency.