Congenital hypogonadotropic hypogonadism (CHH) and Kallmann syndrome (KS) are rare, related diseases that prevent normal pubertal development and cause infertility in affected men and women. However, the infertility carries a good prognosis as increasing numbers of patients with CHH/KS are now able to have children through medically assisted procreation. These are genetic diseases that can be transmitted to patients’ offspring. Importantly, patients and their families should be informed of this risk and given genetic counseling. CHH and KS are phenotypically and genetically heterogeneous diseases in which the risk of transmission largely depends on the gene(s) responsible(s). Inheritance may be classically Mendelian yet more complex; oligogenic modes of transmission have also been described. The prevalence of oligogenicity has risen dramatically since the advent of massively parallel next-generation sequencing (NGS) in which tens, hundreds or thousands of genes are sequenced at the same time. NGS is medically and economically more efficient and more rapid than traditional Sanger sequencing and is increasingly being used in medical practice. Thus, it seems plausible that oligogenic forms of CHH/KS will be increasingly identified making genetic counseling even more complex. In this context, the main challenge will be to differentiate true oligogenism from situations when several rare variants that do not have a clear phenotypic effect are identified by chance. This review aims to summarize the genetics of CHH/KS and to discuss the challenges of oligogenic transmission and also its role in incomplete penetrance and variable expressivity in a perspective of genetic counseling.
Luigi Maione, Andrew A Dwyer, Bruno Francou, Anne Guiochon-Mantel, Nadine Binart, Jérôme Bouligand and Jacques Young
Emmanuelle Kuhn, Luigi Maione, Amir Bouchachi, Myriam Rozière, Sylvie Salenave, Sylvie Brailly-Tabard, Jacques Young, Peter Kamenicky, Patrick Assayag and Philippe Chanson
The effect of pegvisomant on IGF1 levels in patients with acromegaly is well documented, but little is known of its long-term impact on comorbidity.
The aim of this retrospective study was to evaluate the effects of long-term pegvisomant therapy on cardiorespiratory and metabolic comorbidity in patients with acromegaly.
Patients and methods
We analyzed the long-term (up to 10 years) effect of pegvisomant therapy given alone (n=19, 45%) or in addition to somatostatin analogues and/or cabergoline (n=23, 55%) on echocardiographic, polysomnographic and metabolic parameters in respectively 42, 12 and 26 patients with acromegaly followed in Bicêtre hospital.
At the first cardiac evaluation, 20±16 months after pegvisomant introduction, IGF1 levels normalized in 29 (69%) of the 42 patients. The left ventricular ejection fraction (LVEF) improved significantly in patients whose basal LVEF was ≤60% and decreased in those whose LVEF was >70%. The left ventricular mass index (LVMi) decreased from 123±25 to 101±21 g/m2 (P<0.05) in the 17 patients with a basal LVMi higher than the median (91 g/m2), while it remained stable in the other patients. Pegvisomant reduced the apnoea–hypopnea index and cured obstructive sleep apnea (OSA) in four of the eight patients concerned. Long-term follow-up of 22 patients showed continuing improvements in cardiac parameters. The BMI and LDL cholesterol level increased minimally during pegvisomant therapy, and other lipid parameters were not modified.
Long-term pegvisomant therapy not only normalizes IGF1 in a large proportion of patients but also improves cardiac and respiratory comorbidity.
Luigi Maione, Thierry Brue, Albert Beckers, Brigitte Delemer, Patrick Petrossians, Françoise Borson-Chazot, Olivier Chabre, Patrick François, Jérôme Bertherat, Christine Cortet-Rudelli, Philippe Chanson and for the French Acromegaly Registry Group
Acromegaly is a rare disease associated with chronic multisystem complications. National registries have been created in several countries.
The French Registry contains data on acromegaly epidemiology, management and comorbidities recorded over more than three decades, retrospectively until 1999 and prospectively from 1999 to 2012.
Data could be analyzed for 999 of the 1034 patients included in the registry (46% males). Disease control, defined as IGF-I normalization (adjusted for age and sex), was achieved in 75% of patients at the last follow-up visit. Half the patients with uncontrolled disease had IGF-I levels below 1.5 times the upper limit of normal (ULN). The proportion of patients with surgically cured disease did not change markedly over time, whereas the proportion of patients with uncontrolled disease fell and the proportion of patients with medically controlled disease rose. Cardiovascular, metabolic, respiratory and rheumatologic comorbidities and their outcomes were recorded for most patients, and no noteworthy overall deterioration was noted over time. Cancer occurred in 10% of patients, for a standardized incidence ratio of 1.34 (95% CI: 0.94–1.87) in men and 1.24 (0.77–1.73) in women. Forty-one patients died during follow-up, for a standardized mortality ratio of 1.05 (0.70–1.42). Most deaths were due to cancer.
The majority of patients with acromegaly now have successful disease control thanks to the multistep management. The incidence of comorbidities following diagnosis of acromegaly is very low. Life expectancy is now close to that of the general population, probably owing to better management of the GH/IGF-I excess and comorbidities.
Luigi Maione, Giovanna Pala, Claire Bouvattier, Séverine Trabado, Georgios Papadakis, Philippe Chanson, Jérôme Bouligand, Nelly Pitteloud, Andrew A Dwyer, Mohamad Maghnie and Jacques Young
Congenital hypogonadotropic hypogonadism/Kallmann syndrome (CHH/KS) is a rare condition characterized by gonadotropin deficiency and pubertal failure. Adult height (AH) in patients with CHH/KS has not been well studied.
To assess AH in a large cohort of patients with CHH/KS.
A total of 219 patients (165 males, 54 females). Parents and siblings were included.
AH was assessed in patients and family members. AH was compared to the general French population, mid parental target height (TH) and between patients and same-sex siblings. Delta height (∆H) was considered as the difference between AH and parental TH. ∆H was compared between patients and siblings, normosmic CHH and KS (CHH with anosmia/hyposmia), and according to underlying genetic defect. We examined the correlations between ∆H and age at diagnosis and therapeutically induced individual statural gain.
Mean AH in men and women with CHH/KS was greater than that in the French general population. Patients of both sexes had AH > TH. Males with CHH/KS were significantly, albeit moderately, taller than their brothers. ∆H was higher in CHH/KS compared to unaffected siblings (+6.2 ± 7.2 cm vs +3.4 ± 5.2 cm, P < 0.0001). ∆H was positively correlated with age at diagnosis. Neither olfactory function (normosmic CHH vs KS) nor specific genetic cause impacted ∆H. Individual growth during replacement therapy inversely correlated with the age at initiation of hormonal treatment (P < 0.0001).
CHH/KS is associated with higher AH compared to the general population and mid-parental TH. Greater height in CHH/KS than siblings indicates that those differences are in part independent of an intergenerational effect.