In a recent clinical trial, the metabolite l -glutamine was shown to reduce painful crises in sickle cell disease (SCD) patients. To support this observation and identify other metabolites implicated in SCD clinical heterogeneity, we profiled 129 metabolites in the plasma of 705 SCD patients. We tested correlations between metabolite levels and six SCD-related complications (painful crises, cholecystectomy, retinopathy, leg ulcer, priapism, aseptic necrosis) or estimated glomerular filtration rate (eGFR), and used Mendelian randomization (MR) to assess causality. We found a potential causal relationship between l -glutamine levels and painful crises (N = 1278, odds ratio (OR) [95% confidence interval] = 0.68 [0.52–0.89], P = 0.0048). In two smaller SCD cohorts (N = 299 and 406), the protective effect of l -glutamine was observed (OR = 0.82 [0.50–1.34]), although the MR result was not significant (P = 0.44). We identified 66 significant correlations between the levels of other metabolites and SCD-related complications or eGFR. We tested these correlations for causality using MR analyses and found no significant causal relationship. The baseline levels of quinolinic acid were associated with prospectively ascertained survival in SCD patients, and this effect was dependent on eGFR. Metabolomics provide a promising approach to prioritize small molecules that may serve as biomarkers or drug targets in SCD.

Potential causal role of l-glutamine in sickle cell disease painful crises: A Mendelian randomization analysis.

Background Surgical correction of proximal hypospadias is challenging. The complication rate of proximal hypospadias is still high, and the debate over its optimal treatment is ongoing. Duckett’s method is a classic non-staging operation, and two-stage Bracka repair is an attractive alternative procedure. Herein, we retrospectively analyzed the effects of two surgical techniques on proximal hypospadias in order to reduce the complication rates of proximal hypospadias, and analyzed the various risk factors that cause complications. Methods This study retrospectively evaluated 94 consecutive patients who underwent repair of penoscrotal or proximal defects between 2015 and 2019. Patients were assigned to two groups: 46 patients were treated with Bracka and 48 with Duckett. Patient age at surgery, urethral meatus location, and postoperative complications were recorded. One-way analysis of variance (ANOVA) was used to analyze the length and curvature of the penis and the length of the urethral defect. Results There was no significant difference between the two groups in terms of age and type of hypospadias. In the Bracka group, there was 1 case (2.2%) of meatal stenosis after the first stage, which was restored with ureteral dilatation. After second-stage repair, a urethral fistula was noted in 4 cases (8.7%) and strictures in 2 cases (4.3%). In the Duckett group, urethral fistulas were noted in 8 cases (16.7%), strictures in 4 cases (8.3%), partial glans dehiscence in 4 cases (8.3%), and diverticulum in 1 case (2.1%) postoperatively. Compared with the Duckett group, the overall complication rate for Bracka repair was lower (35.4% vs. 13%, P=0.016). In addition, compared with the Duckett group, children with perineal hypospadias who were treated with the Bracka operation had fewer postoperative complications (100% vs. 13%, P=0.015). Risk factor analysis showed that the initial curvature of the penis, initial urethral defect, and degree of penile curvature after skin degloving were not correlated with complications. There was a significant correlation between urethral defects after correction of the chordee and urethral fistulas (P=0.019). Conclusions Compared with the Duckett procedure, the Bracka two-stage repair may be a safer and more reliable approach for proximal hypospadias in children. The Bracka two-stage repair should be used for perineal hypospadias. The larger the urethral defect after chordee correction, the greater the possibility of a postoperative urethral fistula.

/pdf/repair-of-proximal-hypospadias-with-single-stage-ducketts-3t7zx3hr.pdf

Repair of proximal hypospadias with single-stage (Duckett’s method) or Bracka two-stage: a retrospective comparative cohort study

The association between socioeconomic status and the onset age of menarche is still not conclusive. This cross-sectional study was conducted among primary and middle school girls aged 7 to 16 years old in Tianjin, China, to explore the distribution of menarcheal age and its association with socioeconomic status. A self-designed structured questionnaire was completed by students and their parents to collect information on socioeconomic status (i.e., family income, parental education level, living residence), menarcheal status, and covariates (weight status of girls and their parents, sleeping hours per day, physical activity). Information on menarcheal status included whether or not menarche had occurred (Yes/No) and the exact age at menarche. Linear regression analysis was used to explore the association between socioeconomic status and menarcheal age before and after covariate adjustment. Among 1485 eligible girls with complete information, 445 had experienced menarche, with an overall menarche rate of 30%. The mean age at menarche was 12.9 years (95% confidence interval 12.8–13.0). Urban girls experienced menarche earlier than rural girls did (12.1 years vs. 13.5 years). Univariate analysis showed that urban residence and higher parental education were associated with earlier onset of menarche. After covariate adjustment, the significance still existed. However, after adjusting further for residence, the significant association with the parental education disappeared. Only urban residence was still significantly associated, even after further adjustment for parental education and family income, with adjusted regression coefficients (95% confidence interval) of − 1.087 (− 1.340,-0.834), indicating that the onset age of menarche among urban girls was 1.087 years (0.834, 1.340) younger than that among rural girls. Family income was not related to the onset age of menarche in any analyses. Conclusion: Urban-rural differences played a more important role in the early onset of menarche than socioeconomic differences between families.

The influence of socioeconomic status on menarcheal age among Chinese school-age girls in Tianjin, China

Ethnic preference distribution of inborn errors of metabolism: A 4-year study in a multi-ethnic region of China.

Inherited metabolic diseases are a large group of inherited monogenic diseases. Metabolic disorders can cause child disability and mortality. Tandem mass spectrometry is a powerful technology that allows to diagnosis a large number of hereditary metabolic diseases. Clinical manifestations are variable, but more often the damages of nervous system, heart, liver, kidneys, hyperammonemia, hypo/hyperglycemia take place. The disease can make its debut at any age, but the severe forms of the disease manifest at infancy. Early diagnosis and treatment can significantly improve the  prognosis; many countries expand the list of diseases included in screening programs. At the beginning of 2021 in most regions of the Russian Federation mass newborn screening is carried out for five hereditary metabolic diseases. The age and the range of clinical manifestation are variable; therefore, knowledge of this pathology is very important both for pediatricians and therapists, and for specialized doctors. The article presents a brief description of next groups of metabolic diseases: aminoacidopathies, organic acidurias and fatty acid oxidation defects.

/pdf/nasledstvennye-bolezni-obmena-aminoatsidopatii-organicheskie-vzwdzgoar3.pdf

Наследственные болезни обмена: аминоацидопатии, органические ацидемии, дефекты митохондриального β-окисления. Краткий обзор

Maple syrup urine disease (MSUD) is a potentially life-threatening metabolic disorder caused by decreased activity of the branched-chain α-ketoacid dehydrogenase (BCKD) complex. Mutations in four genes (BCKDHA, BCKDHB, DLD and DBT) are associated with MSUD. Here, the presenting symptoms and clinical course of a case of MSUD with a novel DBT gene mutation are described. We describe an infant with MSUD with the DBT gene mutation who had drowsiness and poor appetite as well as abnormal findings upon head magnetic resonance imaging (MRI), plasma amino acid analysis and urine organic acid analysis. Genetic testing revealed that both parents had the heterozygous mutation c.1132C > T (p.378X) in chr1:100672078, and the patient had the homozygous mutations c.1132C > T (p.378X) in chr1:100672078. Once diagnosed with MSUD, the patient’s disease was controlled with a diet of BCAA-free enteral formula and thiamine. The mutation c.1132C > T (p.378X) is a novel DBT gene mutation that is associated with MSUD and always has mild clinical manifestations. After timely BCAA-free nutrition and supplementation with thiamine for the patient, the plasma levels of BCAAs reached a safe level, the abnormal range of the multiple intracranial abnormalities was significantly smaller than before, and the symptoms of drowsiness and poor appetite disappeared.

/pdf/case-report-maple-syrup-urine-disease-with-a-novel-dbt-gene-50i238gx3p.pdf

Case report: maple syrup urine disease with a novel DBT gene mutation

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Case report: maple syrup urine disease with a novel DBT gene mutation

Repair of proximal hypospadias with single-stage (Duckett’s method) or Bracka two-stage: a retrospective comparative cohort study