Constitutional delay of puberty: presentation and inheritance pattern in 48 familial cases

Key features of puberty onset and progression can help distinguish self-limited delayed puberty from congenital hypogonadotrophic hypogonadism

Introduction

Delayed puberty (DP) is a frequent concern for adolescents. The most common underlying aetiology is self-limited DP (SLDP). However, this can be difficult to differentiate from the more severe condition congenital hypogonadotrophic hypogonadism (HH), especially on first presentation of an adolescent patient with DP. This study sought to elucidate phenotypic differences between the two diagnoses, in order to optimise patient management and pubertal development.

Methods

This was a study of a UK DP cohort managed 2015-2023, identified through the NIHR clinical research network. Patients were followed longitudinally until adulthood, with a definite diagnosis made: SLDP if they had spontaneously completed puberty by age 18 years; HH if they had not commenced (complete, cHH), or had commenced but not completed puberty (partial, pHH), by this stage. Phenotypic data pertaining to auxology, Tanner staging, biochemistry, bone age and hormonal treatment at presentation and during puberty were retrospectively analysed.

Results

78 patients were included. 52 (66.7%) patients had SLDP and 26 (33.3%) patients had HH, comprising 17 (65.4%) pHH and 9 (34.6%) cHH patients. Probands were predominantly male (90.4%). Male SLDP patients presented with significantly lower height and weight standard deviation scores than HH patients (height p=0.004, weight p=0.021). 15.4% of SLDP compared to 38.5% of HH patients had classical associated features of HH (micropenis, cryptorchidism, anosmia, etc. p=0.023). 73.1% of patients with SLDP and 43.3% with HH had a family history of DP (p=0.007). Mean first recorded luteinizing hormone (LH) and inhibin B were lower in male patients with HH, particularly in cHH patients, but not discriminatory. There were no significant differences identified in blood concentrations of FSH, testosterone or AMH at presentation, or in bone age delay.

Discussion

Key clinical markers of auxology, associated signs including micropenis, and serum inhibin B may help distinguish between SLDP and HH in patients presenting with pubertal delay, and can be incorporated into clinical assessment to improve diagnostic accuracy for adolescents. However, the distinction between HH, particularly partial HH, and SLDP remains problematic. Further research into an integrated framework or scoring system would be useful in aiding clinician decision-making and optimization of treatment.  .

An Approach to the Patient With Delayed Puberty

Pediatric endocrinologists often evaluate and treat youth with delayed puberty. Stereotypically, these patients are 14-year-old young men who present due to lack of pubertal development. Concerns about stature are often present, arising from gradual shifts to lower height percentiles on the population-based, cross-sectional curves. Fathers and/or mothers may have also experienced later than average pubertal onset. In this review, we will discuss a practical clinical approach to the evaluation and management of youth with delayed puberty, including the differential diagnosis and key aspects of evaluation and management informed by recent review of the existing literature. We will also discuss scenarios that pose additional clinical challenges, including: (1) the young woman whose case poses questions regarding how presentation and approach differs for females vs males; (2) the 14-year-old female or 16-year-old young man who highlight the need to reconsider the most likely diagnoses, including whether idiopathic delayed puberty can still be considered constitutional delay of growth and puberty at such late ages; and finally (3) the 12- to 13-year-old whose presentation raises questions about whether age cutoffs for the diagnosis and treatment of delayed puberty should be adjusted downward to coincide with the earlier onset of puberty in the general population.

Primary amenorrhoea as a manifestation of coeliac disease

Coeliac disease is a systemic autoimmune disorder that has a wide range of clinical manifestations that include abdominal pain, diarrhoea, obstipation, weight loss, short stature and even primary amenorrhoea. It can be asymptomatic, which makes it an underdiagnosed disease. We present a case report of a 15-year-old girl who was referred to a paediatric consultation due to primary amenorrhoea. A detailed clinical history revealed poor weight gain. Physical examination showed that secondary sexual characteristics were present and there was a low body mass index. Ultrasonography images and laboratory tests revealed a normal urogenital system and an adequate gonadal function. Coeliac disease antibodies were positive and the diagnosis was confirmed through duodenal biopsy. The symptom resolved with a gluten-free diet. An approach to primary amenorrhoea should always include investigation of a systemic illness as it is a rare but treatable diagnosis.

Characteristic dynamics of height and weight in preschool boys with constitutional delay of growth and puberty or hypogonadotropic hypogonadism

OBJECTIVE

Constitutional delay of growth and puberty (CDGP) is a frequent variant of the normal leading to short stature and/or pubertal delay. To distinguish CDGP from hypogonadotropic hypogonadism (HH), we evaluated height, growth and weight pattern of CDGP and HH in the first 5 years of life.

DESIGN AND PATIENTS

We studied retrospectively height and weight in the first 5 years (y) of life in 54 boys with CDGP and 8 boys with HH.

RESULTS

In boys with CDGP, height-SDS decreased (change -0.94 (interquartile range [IQR] -1.69 to -0.05); P < 0.001) between birth and 2 years. BMI-SDS decreased (change -0.38 (IQR -1.21-0.16); P < 0.001) in the same time period. There were no significant changes in height-SDS or BMI-SDS between 2 years and 5 years, while height-SDS (change + 1.49 (IQR 1.02-1.95); P < 0.001) and BMI-SDS (change + 0.91 (IQR 0.12-1.69); P < 0.001) increased between pubertal and adult age. In boys with HH, height-SDS and BMI-SDS did not change significantly in the first 5 years of life. Height-SDS decreased (change -1.39 (IQR -1.96 to -0.67); P = 0.018) significantly between 5 years of life and puberty, while there were no significant changes in BMI-SDS in this time period. At pubertal age, BMI-SDS was significantly (P = 0.001) higher in boys with HH compared with boys with CDGP.

CONCLUSION

Height deflection and weight deflection in CDGP occur already during the first two years of life in contrast to HH. This different pattern of growth and weight might be helpful to distinguish CDGP from HH.

The Genetic Basis of Delayed Puberty

Delayed pubertal onset has many etiologies, but on average two-thirds of patients presenting with late puberty have self-limited (or constitutional) delayed puberty. Self-limited delayed puberty often has a strong familial basis. Segregation analyses from previous studies show complex models of inheritance, most commonly autosomal dominant, but also including autosomal recessive, bilineal, and X-linked. Sporadic cases are also observed. Despite this, the neuroendocrine mechanisms and genetic regulation remain unclear in the majority of patients with self-limited delayed puberty. Only rarely have mutations in genes known to cause aberrations of the hypothalamic-pituitary-gonadal axis been identified in cases of delayed puberty, and the majority of these are in relatives of patients with congenital hypogonadotropic hypogonadism (CHH), for example in the FGFR1 and GNRHR genes. Using next generation sequencing in a large family with isolated self-limited delayed puberty, a pathogenic mutation in the CHH gene HS6ST1 was found as the likely cause for this phenotype. Additionally, a study comparing the frequency of mutations in genes that cause GnRH deficiency between probands with CHH and probands with isolated self-limited delayed puberty identified that a significantly higher proportion of mutations with a greater degree of oligogenicity were seen in the CHH group. Mutations in the gene IGSF10 have been implicated in the pathogenesis of familial late puberty in a large Finnish cohort. IGSF10 disruption represents a fetal origin of delayed puberty, with dysregulation of GnRH neuronal migration during embryonic development presenting for the first time in adolescence as late puberty. Some patients with self-limited delayed puberty have distinct constitutional features of growth and puberty. Deleterious variants in FTO have been found in families with delayed puberty with extremely low BMI and maturational delay in growth in early childhood. Recent exciting evidence highlights the importance of epigenetic up-regulation of GnRH transcription by a network of miRNAs and transcription factors, including EAP1, during puberty. Whilst a fascinating heterogeneity of genetic defects have been shown to result in delayed and disordered puberty, and many are yet to be discovered, genetic testing may become a realistic diagnostic tool for the differentiation of conditions of delayed puberty.