Role of genetic investigation in the diagnosis of short stature in a cohort of Italian children

BACKGROUND

Short stature (SS) is defined as height more than 2 standard deviations below the mean for age and sex. Hypothyroidism, celiac disease, growth hormone deficiency, hormonal abnormalities, and genetic conditions are among its causes. A wide range of conditions often due to largely unknown genetic variants can elude conventional diagnostic workup.

AIM

We used next-generation sequencing (NGS) to better understand the etiology of SS in a cohort of Italian children.

PATIENTS AND METHODS

The study sample was 125 children with SS of unknown origin referred to our Institute between 2015 and 2021. All had undergone complete auxological and hormonal investigations to exclude common causes of SS. Genetic analysis was performed using a NGS panel of 104 genes. Clinical data were reviewed to clarify the pathogenicity of the variants detected.

RESULTS

In this cohort, 43 potentially causing variants were identified in 38 children. A syndromic genetic condition was diagnosed in 7: Noonan syndrome in 3, Leri-Weill syndrome in 3, and hypochondroplasia in 1. Moreover, 8 benign variants and other 37 like benign variants were found. In 88 children, 179 variants of uncertain significance (VUS) were identified. No variant was found in 16 children.

CONCLUSION

Genetic analysis is a useful tool in the diagnostic workup of patients with SS, in adapting management and treatment, and in identifying syndromes with mild atypical clinical features. The role of VUS should not be underestimated, particularly when multiple VUS with possible mutual worsening effects are present in the same child.

Analysis of the impact of COVID-19 pandemic on functional gastrointestinal disorders among paediatric population

OBJECTIVE

Functional gastrointestinal disorders are common gastrointestinal diseases. The pathophysiology is multifactorial and psychosocial distress worsens symptoms severity. Since the end of 2019 the world has been facing COVID-19 pandemic. The associated control measures have affected the psychological health of people. The aim of the present study is to evaluate the impact of the COVID-19 pandemic on the prevalence of functional gastrointestinal disorders among Italian children and adolescents.

PATIENTS AND METHODS

The study sample is composed of 407 patients (187 males, 220 females), aged from 10 to 17 years. The mean age is 14.27 ± 2.24 years. The study was conducted through the Italian version of the Questionnaire on Pediatric Gastrointestinal Symptoms-Rome III Version.  The prevalence of each disorder has been calculated as the ratio of affected subjects for each disease and the total number of effective cases for that specific disease.

RESULTS

The study demonstrates that the prevalence of Functional Gastrointestinal Disorder in Italian children, during the COVD-19 pandemic, is higher, compared with the one reported in the previous studies. The most frequent disorders are Abdominal Migraine and Irritable Bowel Syndrome.

CONCLUSIONS

Our study is the first one which provides data of the prevalence of Functional gastrointestinal disorders in sample of Italian adolescents, during the COVID-19 pandemic. The study underlines the need to focus on stress management, in order to reduce the effects of the lockdown on the psychological wellness of the youngest.

Hormonal replacement therapy in adolescents and young women with chemo- or radio-induced premature ovarian insufficiency: Practical recommendations

In women with premature ovarian insufficiency (POI), hormonal therapy (HT) is indicated to decrease the risk of morbidity and to treat symptoms related to prolonged hypoestrogenism. While general recommendations for the management of HT in adults with POI have been published, no systematic suggestions focused on girls, adolescents and young women with POI following gonadotoxic treatments (chemotherapy, radiotherapy, stem cell transplantation) administered for pediatric cancer are available. In order to highlight the challenging issues specifically involving this cohort of patients and to provide clinicians with the proposal of practical therapeutic protocol, we revised the available literature in the light of the shared experience of a multidisciplinary team of pediatric oncologists, gynecologists and endocrinologists. We hereby present the proposals of a practical scheme to induce puberty in prepubertal girls and a decisional algorithm that should guide the clinician in approaching HT in post-pubertal adolescents and young women with iatrogenic POI.

Diagnostic Effectiveness of Simultaneous Thyroxine and Thyroid-Stimulating Hormone Screening Measurements. Thirteen Years' Experience in the Northeast Italian Screening Programme

Objectives:

To evaluate the effectiveness of thyroid-stimulating hormone (TSH) and thyroxine [T4) measurements at neonatal screening for congenital hypothyroidism, we compared our false-negative results with those we would have obtained if we had used TSH screening alone.

Subjects and methods:

Between January 1989 and December 2001 745,258 newborns were screened (98.3% of total born) for congenital hypothyroidism in northeast Italy. T4 and TSH were measured simultaneously on blood spots collected after birth. Between 1989 and 1998, semiquantitative total T4 (tT4) and TSH concentrations were measured by radiolabelled immunological assay and, from 1999 to 2001, using time-resolved fluorometer Delfia instruments (EG&G Wallac Oy, Finland) and fluoroimmunometric assay (Delfia neonatal hTSH and T4 kits).

Results:

Ten neonates were missed by our screening programme (normal tT4 and TSH) and classified as false negatives; these infants were diagnosed later in life with central hypothyroidism. If we had measured TSH alone in our screening programme, we would have missed an additional 21 patients with low tT4 and normal TSH; of these, four were affected by central hypothyroidism and 17 were diagnosed within the second month of life as affected by primary hypothyroidism with delayed TSH rise.

Conclusions:

Simultaneous T4 and TSH measurements at neonatal screening can miss patients affected by central hypothyroidism. However, this screening procedure allows identification of cases of central hypothyroidism with low T4 values and those neonates affected by primary hypothyroidism with delayed TSH rise who we would have missed by using the TSH measure alone.

Interplay between Raman and polarization effects in next-generation passive optical networks

In this paper, we study in details some Raman-induced impairments that arise in Next-Generation Passive Optical Networks (NG-PON2) in a full coexistence scenario between GPON and TWDM-PON. The main new contribution of this paper is to take into account the polarization launches of the different signals at the transmitter, in order to find the best polarization arrangement. We found that launching the TWDM-PON wavelengths on alternately orthogonal polarization minimizes the Raman depletion effect on GPON over all possible PMD values, thus resulting in the optimal polarization launching condition, while any other polarization launch has a higher out of service probability for realistic PMD values.

Growth hormone and early treatment

Growth hormone (GH) treatment is approved by the US Food and Drug Administration (FDA) not only for GH deficiency (GHD) but also for other childhood growth disorders with growth failure and/or short stature. GHD is the most frequent endocrine disorder presenting with short stature in childhood. During neonatal period, metabolic effects due to congenital GHD require a prompt replacement therapy to avoid possible life-threatening complications. In childhood and adolescence, growth impairment is the most evident effect of GHD and early treatment has the aim of restore normal growth and to reach normal adult height. We reassume in this review the conditions causing GHD and the diagnostic challenge to reach an early diagnosis, and an early treatment, necessary to obtain the best results. Finally, we summarize results obtained in clinical studies about pediatric patients with GHD treated at an early age, in which a marked early catch-up growth and a normalization of adult height were obtained.

Significant association among growing pains, vitamin D supplementation, and bone mineral status: results from a pilot cohort study

The aim of our study was to analyze the possible relationship between growing pains, vitamin D levels, and bone mineral status. We enrolled 33 children affected by growing pains. Their pain intensity was evaluated through a questionnaire using the Wong-Baker Faces Pain Rating Scale for pain assessment. Serum 25-hydroxyvitamin D (25-OH-D), parathyroid hormone (PTH), and alkaline phosphatase levels were measured as well. A quantitative ultrasound assessment (QUS) was also done, measuring both the amplitude-dependent speed of sound (AD-SOS) and the bone transmission time (BTT), correlating, respectively, with bone density and with cortical thickness. After 3 and 24 months of vitamin D supplementation, we re-evaluated pain intensity and laboratory results. After 24 months we re-assessed QUS parameters. At the beginning of the study the children reported a mean growing pain intensity of 7.5 ± 1.6 SD. The mean values of 25-OH-D and PTH levels were 15.7 ± 6.9 ng/ml and 57.3 ± 27.3 pg/ml, respectively. The AD-SOS Z score was -0.53 ± 1.19 SD, and the mean value of the BTT Z score was -0.72 ± 0.96 SD. After the first 3 months of vitamin D supplementation we observed an increase in 25-OH-D levels (34.1 ± 17.8, p < 0.001) and a reduction in both PTH levels (47.3 ± 30.6, p = 0.135) and pain intensity (2.7 ± 2.2, p < 0.001). After 24 months we observed a further significant reduction in the pain intensity (3.9 ± 3.4, p < 0.001) and in PTH levels (43.7 ± 28.5, p = 0.004) and an improvement in the QUS parameters, in particular in BTT Z scores (p = 0.014). Our study suggests an interesting relationship between growing pains, vitamin D levels and bone mineral status.

Compatibility between coherent reflective burst-mode PON and TWDM-PON physical layers

We discuss the compatibility between reflective PON architectures and the recently defined ITU-T G.989.1 TWDM-PON. Focusing on the upstream, we experimentally demonstrate that, by using burst-mode coherent detection at OLT, reflective PON can achieve the specification target set for TWDM-PON, without requiring precise wavelength accuracy at ONU. Compared to the companion ECOC 2013 paper, we investigate on the differential optical path loss (DOPL) issue, proposing a simple SOA gain control algorithm to achieve reliable transmission for DOPL up to 17 dB.

Genotype in the diagnosis of 21-hydroxylase deficiency: who should undergo CYP21A2 analysis?

AIMS

to confirm the diagnosis of 21-hydroxylase deficiency (21-OHD) by the analysis of CYP21A2 gene in infants with clinical and/or biochemical features of 21-OHD in order to clarify which patients to submit to genetic analysis; to analyze the genotype-phenotype concordance in these infants.

SUBJECTS AND METHODS

We studied 25 children with clinical and/or biochemical features of 21-OHD. All of them and their parents were submitted to genetic analysis of CYP21A2. Patients were classified in 3 groups according to mutations' severity: severe (group A), moderate (group B) or mild (group C).

RESULTS

CYP21A2 gene mutations were found in 17 children. Whereas all infants of groups A and B presented a classical form of 21- OHD, children of group C had a non-classical form of 21-OHD. Four infants resulted heterozygotes and 4 children were wildtype. A girl clinically presenting a non-classical form of 21-OHD resulted compound heterozygote with one of the mutations not described in literature (R25W) and whose residual enzymatic activity is not already known. All affected children presented a 17-OHP level after ACTH stimulation greater than 100 nmol/l. We found an optimal concordance between 17-OHP levels after ACTH test and genotype.

CONCLUSIONS

CYP21A2 analysis permitted to confirm the diagnosis of 21-OHD in 68% of our children. To improve this percentage we suggest to perform the CYP21A2 analysis only when 17-OHP after ACTH test is greater than 100 nmol/l. Moreover, we found an optimal genotype-phenotype concordance in the 21-OHD patients.

Optimization of self-coherent reflective PON to achieve a new record 42 dB ODN power budget after 100 km at 1.25 Gbps

We demonstrate a greater than 42 dB optical distribution network power budget in the upstream of a 1.25 Gbps self-coherent reflective PON after 100 km of installed fibers, using off-the-shelf optoelectronic components, improving our previous result by 4 dB. We discuss all system optimizations introduced in the setup in order to reach such a result, including 8B/10B high-pass filtering and Faraday rotation at the ONU.

Characterization of uncooled RSOA for upstream transmission in WDM reflective PONs

We investigate on the uncooled RSOA driving parameters in WDM reflective PONs, focusing on an upstream path at 1.25 Gbit/s using pure binary modulation. We show how the optimal values change using direct-detection or self-coherent receivers. In particular, for the latter, the driving point optimization allows a gain of more than 3 dB in terms of ODN loss compared to a standard On-Off Keying, generating a quasi-PSK modulation. We also address operating temperature and wavelength dependence issues.

Serum inhibin B levels before and after varicocelectomy in early adolescence

BACKGROUND

Whereas no clear relationship has been observed between varicocelectomy and serum inhibin B levels in men, in adolescents comparison between inhibin B levels before and after varicocelectomy is lacking.

AIM

To evaluate the effect of varicocele surgical treatment on inhibin B levels in adolescents at the beginning of puberty compared to a group of healthy adolescents.

SUBJECTS AND METHODS

We studied 28 adolescents in Tanner 2 pubertal stage with a grade III left-sided varicocele (patients) compared to 13 age and pubertal stage-matched healthy adolescents (controls). All patients underwent blood tests to determine serum inhibin B levels before and 6 months after varicocelectomy by Palomo procedure. For comparison we investigated inhibin B levels in controls and repeated this test 6 months later. Testicular ultrasound was performed for patients only.

RESULTS

Baseline inhibin B concentrations of patients and controls were 109.90 ± 40.26 and 109.33 ± 38.34 pg/ml, respectively. No significant changes were observed in patients' inhibin B concentrations after varicocelectomy (116.00 ± 42.65 pg/ml), or in controls during the 6 months' follow-up (99.12 ± 30.09 pg/ml). Doppler examination after treatment shows a complete resolution of varicocele in all the patients without alterations in testicular parenchyma.

CONCLUSIONS

Varicocelectomy performed on adolescents at T2 pubertal stage might be useful to avoid alteration in inhibin B production and consequently in testicular function. Further studies are necessary to confirm the prognostic value of inhibin B levels and the benefit of early varicocelectomy in preserving the fertility of these adolescents.

[Influence of thyroid morphology on psychomotor development in patients with congenital hypothyroidism during 8 year follow-up]

AIM

The aim of this paper was to evaluate the impact of thyroid morphology on auxological and neuropsychological development in children affected by congenital hypothyroidism (CH), treated with levothyroxine, up to 8 years of age.

METHODS

Fifty-three children affected by CH divided into 3 groups on the basis of thyroid morphology determined at birth: patients with athyreosis (N=17), with ectopic gland (N=23), with in situ thyroid (N=13). The developmental quotient (DQ) was evaluated by the Brunet-Lezine test up to 3 years, and intelligent quotient (IQ) by the Terman-Merril test after 3 years of age.

RESULTS

DQs at one year in athyreotic patients are lower (P<0,05) as compared to those determined in patients with other thyroid morphology. Later on these patients still showed lower DQ and IQ values than in other groups, although statistically not significant.

CONCLUSION

Thyroid morphology seems to be fundamental in psychomotor development, in fact patients with athyreosis show a transient impairment at one year of age. This difference could be transient or to have repercussions on adult. Individualization of the starting dose of levothyroxine on the basis of thyroid morphology, could be useful.

Body size and early growth in appropriate- and large-for-gestational-age infants

AIMS

To study weight, length, body composition, sleeping energy expenditure (SEE), and respiratory quotient (RQ) at birth and at 5 mo of age in both adequate-for-gestational-age (AGA) and large-for-gestational-age (LGA) subjects; to compare the changes in body weight and body composition adjusting for gender, age, SEE, RQ and several maternal factors; to investigate the contribution of initial SEE and RQ to changes in body weight and body composition.

METHODS

Sixty-nine neonates were recruited among term infants in the University Hospital of Verona, Italy. Forty-nine subjects participated until follow-up. At birth and follow-up, weight and length were measured and arm-fat area and arm-muscle area were calculated from triceps and subscapular skinfolds. SEE and RQ were measured by indirect calorimetry.

RESULTS

At birth, weight, length, arm-muscle and arm-fat areas were significantly higher in LGA subjects than in AGA subjects. Weight status, SEE and RQ at birth did not explain the relative weight change after adjusting for gestational weight, placental weight, age at follow-up and gender. Arm-fat area and weight/length ratio at birth were negatively associated with relative changes in body weight after adjusting for the above variables (p < 0.05).

CONCLUSION

Early growth from birth to 5 mo of life is significantly affected by body size and adiposity at birth. Fatter newborns had a slower growth rate than thinner newborns.