Novel rare variants in FGFR1 and clinical characteristics analysis in a series of congenital hypogonadotropic hypogonadism patients.

OBJECTIVE: We aimed to analyse FGFR1 rare variants in a series of Chinese congenital hypogonadotropic hypogonadism (CHH) patients. In addition, we intended to understand the clinical characteristics and the response to treatment of CHH patients with FGFR1 rare variants. PATIENTS AND METHODS: A total of 357 CHH patients were recruited at Peking Union Medical College Hospital. We used Sanger sequencing to analyse FGFR1 gene. In silico analysis was carried out to study the pathogenicity of novel missense variants. The clinical, endocrinological and therapeutic effects from patients carrying FGFR1 rare variants were analysed retrospectively. RESULTS: Thimissense mutations.rty patients in this series were found to harbour 29 FGFR1 rare variants, with 8 recurrent and 21 novel variants. After comprehensive analysis, 18 out of 21 novel variants were classified as likely pathogenic (LP) ones. These variants are widely spread throughout the FGFR1 gene and almost all FGFR1 functional domains, which exhibited no hot spot. Cryptorchidism, cleft palate and dental abnormality incidence in this CHH series that possessed FGFR1 LP variants were approximately 38.5%, 7.6% and 3.8%, respectively. Among patients who accepted the fertility-promoting treatment, 8 out of 10 patients succeeded in spermatogenesis. CONCLUSIONS: Eighteen novel LP variants were found to expand the spectrum of FGFR1 rare variants. In CHH patients possessing FGFR1 variants, we found that the rate of spermatogenesis was high following fertility-promoting therapy and the existence of cryptorchidism may represent the underlying factors which affect spermatogenesis.

Mechanisms of Central Hypogonadism.

Reproductive function depends upon an operational hypothalamo-pituitary-gonadal (HPG) axis. Due to its role in determining survival versus reproductive strategies, the HPG axis is vulnerable to a diverse plethora of signals that ultimately manifest with Central Hypogonadism (CH) in all its many guises. Acquired CH can result from any pituitary or hypothalamic lesion, including its treatment (such as surgical resection and/or radiotherapy). The HPG axis is particularly sensitive to the suppressive effects of hyperprolactinaemia that can occur for many reasons, including prolactinomas, and as a side effect of certain drug therapies. Physiologically, prolactin (combined with the suppressive effects of autonomic neural signals from suckling) plays a key role in suppressing the gonadal axis and establishing temporary CH during lactation. Leptin is a further key endocrine regulator of the HPG axis. During starvation, hypoleptinaemia (from diminished fat stores) results in activation of hypothalamic agouti-related peptide neurons that have a dual purpose to enhance appetite (important for survival) and concomitantly suppresses GnRH neurons via effects on neural kisspeptin release. Obesity is associated with hyperleptinaemia and leptin resistance that may also suppress the HPG axis. The suppressibility of the HPG axis also leaves it vulnerable to the effects of external signals that include morphine, anabolic-androgenic steroids, physical trauma and stress, all of which are relatively common causes of CH. Finally, the HPG axis is susceptible to congenital malformations, with reports of mutations within >50 genes that manifest with congenital CH, including Kallmann Syndrome associated with hyposmia or anosmia (reduction or loss of the sense of smell due to the closely associated migration of GnRH with olfactory neurons during embryogenesis). Analogous to the HPG axis itself, patients with CH are often vulnerable, and their clinical management requires both sensitivity and empathy.

A novel heterozygous intron mutation in SEMA7A causing kallmann syndrome in a female.

Kallmann syndrome (KS) is a rare inherited disorder, which has significantly genotypic and phenotypic heterogeneity. KS is clinically characterized by the combination of hypogonadotropic hypogonadism and hypo/anosmia. At present, there is no relevant report that intron mutation in SEMA7A gene helps induce KS. A 17-year-old Chinese female (46, XX) came to our department due to primary amenorrhea, who actually had hyposmia since her childhood. Hypogonadotropic hypogonadism was then detected. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels were remarkably low. And estradiol level was extremely low. The laboratory test results were consistent with KS. A heterozygous point mutation of intron 13 in SEMA7A (NM_003612.3:c.1640-3C > A) was identified. The patient received the treatment of pulsatile gonadotropin-releasing hormone (GnRH) pump, which could imitate physiological ovarian stimulation, thus resulting in mature follicle and a peak of LH. The patient was injected subcutaneously every 90 min with a dose of 10 µg per pulse, which had bona efficacy. She acquired menarche at about 43 days after the treatment. We firstly report a case of KS caused by a novel mutation site in the intron of SEMA7A gene. We mainly provide insight into the clinical manifestations, genetic diagnosis and treatment of KS.

Live birth in male de novo Kallmann syndrome after cross-generational genetic sequencing.

PURPOSE: To present the first case proposing the use of preimplantation genetic testing for monogeneic disorders for Kallmann syndrome, providing comprehensive care in the genomic era of precision medicine. METHODS: Gonadotropin therapy was used for spermatogenesis, followed by in vitro fertilization by intracytoplasmic sperm injection and embryo transfer. Cross-generational targeted next-generation sequencing was then done for genes known to cause Kallmann syndrome. RESULTS: A heterozygous mutation at codon 102 of the FGFR1 gene was found in the patient, but the father was found to have the same mutation yet is unaffected by Kallmann syndrome. Since no causative mutation was found, a de novo or sporadic mutation was suspected as the cause of Kallmann syndrome in this case. CONCLUSIONS: Comprehensive care must be available for male Kallmann syndrome patients, as treatment should not stop at spermatogenesis, but continue with genetic counseling due to possible inheritance.

Arachnoid cyst: a further anomaly associated with Kallmann syndrome?

BACKGROUND: Kallmann syndrome (KS) is defined by the association of hypogonadotropic hypogonadism and anosmia. It is characterized by a significant clinical and genetic heterogeneity; actually, it may present several non-reproductive non-olfactory anomalies, and all the ways of genetic transmission can be involved in the inheritance of the disease. Although six pathogenesis-related genes have been identified so far, KS remains sporadic in 70 % of the cases, and the genetic diagnosis is not available for all of them. The purpose of this paper is to present a further disease that can enrich the wide spectrum of KS variability, that is cerebral arachnoid cyst. CASE DESCRIPTION: This 11-year-old boy presented with the typical characteristics of KS together with those related to a sylvian arachnoid cyst. He was admitted because of worsening headache. At the admission, the physical examination revealed eunuchoid aspect, micropenis, previous cryptorchidism, and anosmia. MRI pointed out a large, left sylvian arachnoid cyst, agenesia of the olfactory bulbs/tracts complex, and hypoplasia of the left olfactory sulcus. The child was operated on by endoscopic fenestration of the cyst, followed by transient external drainage for subdural hygroma and microscopic fenestration for recurrence of the cyst. His statural growth is normal but the sexual development still delayed in spite of hormone replacement therapy. CONCLUSION: According to the present and the other four cases in the literature, arachnoid cyst should be included among the anomalies possibly accompanying KS date although this association seems to be occasional as far as embryogenesis and physiopathology are concerned.

Functional rescue of Kallmann syndrome-associated prokineticin receptor 2 (PKR2) mutants deficient in trafficking.

Mutations in the G protein-coupled prokineticin receptor 2 (PKR2) are known to cause Kallmann syndrome and idiopathic hypogonadotropic hypogonadism manifesting with delayed puberty and infertility. Some of the mutant receptors are not routed to the cell surface; instead, they are trapped in the cellular secretory pathway. The cell-permeant agonists/antagonists have been used to rescue some membrane receptors that are not targeted onto the cell membrane. Here, we chose three disease-associated mutations (W178S, G234D, and P290S), which all resulted in retention of PKR2 intracellularly. We show that a small molecule PKR2 antagonist (A457) dramatically increased cell surface expression and rescued the function of P290S PKR2, but had no effect on W178S and G234D PKR2. Furthermore, we also tested chemical chaperone glycerol on the cell surface expression and function of PKR2 mutants. Treatment with 10% glycerol significantly increased the cell surface expression and signaling of P290S and W178S PKR2. These data demonstrate that some Kallmann syndrome-associated, intracellularly retained mutant PKR2 receptors can be functionally rescued, suggesting a potential treatment strategy for patients bearing such mutations.

[Clinical diagnosis and treatment of male Kallmann syndrome].

OBJECTIVE: To investigate the diagnosis and treatment of male Kallmann syndrome. METHODS: We retrospectively analyzed the clinical data of 12 cases of male Kallmann syndrome, 3 treated for male sterility and the other 9 for secondary sex characteristics dysplasia and external genitalia developmental anomalies, all by combined replacement therapy with human chorionic gonadotropin (hCG), human menopause gonadotropin (hMG) and testosterone undecanoate for 6 months to 3 years. We compared the secondary sexual development and serum sex hormone levels of the patients before and after treatment. RESULTS: After 9 months of treatment, all the 12 patients showed significant improvement in the penile length, testicular volume and sex hormone levels (P < 0.01), with different degrees of promotion of the secondary sexual development. Three married cases could have normal sexual intercourse, and one of them achieved normal pregnancy. CONCLUSION: The clinical characteristics of Kallmann syndrome include lack of gonadotropins, lower gonad function and loss or reduction of olfactory sensation. Replacement therapy with hCG, hMG and androgens is an effective treatment method. However, no effective therapy is now available for olfactory dysfunction. Early diagnosis and hormone replacement therapy can best alleviate its clinical symptoms and eventually achieve fertility.

Case Report: Multiple prolactinomas in a young man with Kallmann syndrome and familial hypocalciuric hypercalcemia.

Introduction: The occurrence of prolactinomas in sex hormone treated patients with central hypogonadism is extremely rare. Case presentation: We present a Caucasian male patient who was diagnosed with Kallmann syndrome (KS) at age 15 years. Testosterone treatment was started. At age 26 the patient presented with mild headache. MRI revealed two separate pituitary adenomas along with the absence of the olfactory bulbs. Given the presence of marked hyperprolactinemia (17x upper limit of the reference range) the diagnosis prolactinoma was made and treatment with cabergoline was started which resulted in a complete biochemical response and in marked reduction of both adenomas in size. Hypogonadism persisted and testosterone replacement therapy was continued. Genetic testing of genes associated with pituitary tumors, Kallmann syndrome and idiopathic hypogonadotropic hypogonadism was negative. Mild concomitant hypercalcemia in accordance with familial hypocalciuric hypercalcemia (FHH) prompted mutation analysis of the calcium receptor (CASR) gene which yielded a pathogenic inactivating variant. Discussion/conclusion: The presence of two separate prolactinomas in a patient with KS has not yet been reported in the literature. The effect of sex hormone treatment of KS patients on the possible development of prolactinoma is unknown at present. The occurance of multiple prolactinomas in our patient suggests increased susceptibility. Although CaSR is expressed in GnRH neurons in mouse brain and CaSR deficient mice have a reduced hypothalamic GnRH neuronal population, the relevance of the CASR gene variant in our patient for the KS phenotype is unclear at present.

A rare case of a 34-year-old patient diagnosed late with Kallmann syndrome: case report.

Kallmann syndrome (KS) is a rare genetic disorder manifested by the combination of hypogonadotropic-hypogonadism and olfactory dysfunction. It is usually diagnosed at 14 - 16 years of age due to delayed puberty. However, delays in diagnosis have been reported in a few cases. We presented a 34-year-old man presented with primary infertility as the chief complaint. Physical examination revealed bilateral gynecomastia, Tanner stage 2, and anosmia. Hormonal studies show a hypogonadotropic hypogonadism profile. Genetic testing revealed a normal male karyotype. Abdominal ultrasonography (USG) revealed a small prostate, and testicular USG demonstrated small testicles. Neuroimaging study revealed olfactory bulb agenesis and hypoplasia of the olfactory sulcus. Treatment was done by testosterone replacement therapy, and the patient is now on a regular follow-up. In conclusion, suspected clinical features of KS may guide the diagnosis with comprehensive hormonal and imaging studies. However, the reported patient was diagnosed extremely late.

Predictors of pilosebaceous unit responsiveness to testosterone therapy in patients with hypogonadotrophic hypogonadism.

Testosterone replacement therapy is the mainstay of treatment in male patients with isolated hypogonadotrophic hypogonadism (HH) to achieve virilisation. However, responsiveness of pilosebaceous unit (PSU) to testosterone replacement therapy in these patients is quite variable. Androgen action is inversely proportional to the number of CAG repeats in exon 1 of androgen receptor gene; therefore, we hypothesised that CAG repeat length contributes to testosterone responsiveness in patients with HH. The CAG repeat length in 21 well-virilised men (hair score > 30, responders) and 25 poorly virilised men (hair score ≤ 30, non-responders) with HH on optimal testosterone replacement therapy at least for a period of 1 year was analysed. Serum LH, FSH, testosterone and 17 ß oestradiol were estimated. Polymerase chain reaction (PCR) amplification of exon 1 of androgen receptor gene was performed from genomic DNA, and these PCR-amplified products were sequenced for the number of CAG repeats. The difference between number of CAG repeats in responders and non-responders was statistically significant (19.19 ± 3.25 and 22.24 ± 2.65, P = 0.001) and showed a strong negative correlation with total body hair score (r = -0.538 and P = 0.0001). In conclusion, these results suggest that the number of CAG repeats influences the responsiveness of PSU to testosterone treatment in patients with HH.

[Kallmann syndrome]. / Kallmann-Syndrom.

The Kallmann syndrome is a very rare congenital association of gonadotropin-releasing hormone deficiency and hyposmia or anosmia. Clinically it is characterized by low serum concentrations of testosterone and inadequate low levels of luteinizing hormone and follicle-stimulating hormone as well as incomplete sexual maturation, lack of secondary sexual features (facial and body hair growth, deepening of the voice), micropenis and sometimes even cryptorchidism. The reduced or absent sense of smell is typical for the Kallmann syndrome and distinguishes this syndrome from other causes of hypogonadotropic hypogonadism. Additional findings may include synkinesia, hearing loss, unilateral renal aplasia, brachy- or syndactyly, agenesis of corpus callosum, cleft palate and dental agenesis. A 19-year-old man presented to our male infertility clinic with delayed sexual maturation, eunuchoid habitus, micropenis, cryptorchidism, erectile dysfunction and absence of ejaculation, anemia and osteoporosis as well as low serum concentrations of luteinizing hormone, follicle-stimulating hormone and testosterone in combination with hyposmia.

Hypogonadotrophic short statured with anosmia: Kallmann's syndrome.

Short stature with loss of secondary sex characters can occur due to genetic disorders. One of them is Kallmann's syndrome. The condition has been noted to be present in families. It is associated with anosmia and hypogonadism. We are presenting a case of young boy who was short statured and had anosmia with multiple hormonal deficiencies.

Reversal of idiopathic hypogonadotropic hypogonadism.

BACKGROUND: Idiopathic hypogonadotropic hypogonadism, which may be associated with anosmia (the Kallmann syndrome) or with a normal sense of smell, is a treatable form of male infertility caused by a congenital defect in the secretion or action of gonadotropin-releasing hormone (GnRH). Patients have absent or incomplete sexual maturation by the age of 18. Idiopathic hypogonadotropic hypogonadism was previously thought to require lifelong therapy. We describe 15 men in whom reversal of idiopathic hypogonadotropic hypogonadism was sustained after discontinuation of hormonal therapy. METHODS: We defined the sustained reversal of idiopathic hypogonadotropic hypogonadism as the presence of normal adult testosterone levels after hormonal therapy was discontinued. RESULTS: Ten sustained reversals were identified retrospectively. Five sustained reversals were identified prospectively among 50 men with idiopathic hypogonadotropic hypogonadism after a mean (+/-SD) duration of treatment interruption of 6+/-3 weeks. Of the 15 men who had a sustained reversal, 4 had anosmia. At initial evaluation, 6 men had absent puberty, 9 had partial puberty, and all had abnormal secretion of GnRH-induced luteinizing hormone. All 15 men had received previous hormonal therapy to induce virilization, fertility, or both. Among those whose hypogonadism was reversed, the mean serum level of endogenous testosterone increased from 55+/-29 ng per deciliter (1.9+/-1.0 nmol per liter) to 386+/-91 ng per deciliter (13.4+/-3.2 nmol per liter, P<0.001), the luteinizing hormone level increased from 2.7+/-2.0 to 8.5+/-4.6 IU per liter (P<0.001), the level of follicle-stimulating hormone increased from 2.5+/-1.7 to 9.5+/-12.2 IU per liter (P<0.01), and testicular volume increased from 8+/-5 to 16+/-7 ml (P<0.001). Pulsatile luteinizing hormone secretion and spermatogenesis were documented. CONCLUSIONS: Sustained reversal of normosmic idiopathic hypogonadotropic hypogonadism and the Kallmann syndrome was noted after discontinuation of treatment in about 10% of patients with either absent or partial puberty. Therefore, brief discontinuation of hormonal therapy to assess reversibility of hypogonadotropic hypogonadism is reasonable. (ClinicalTrials.gov number, NCT00392756 [ClinicalTrials.gov].).

Congenital hypogonadotropic hypogonadism/Kallmann syndrome is associated with statural gain in both men and women: a monocentric study.

CONTEXT: 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. OBJECTIVE: To assess AH in a large cohort of patients with CHH/KS. PATIENTS: A total of 219 patients (165 males, 54 females). Parents and siblings were included. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Gonadotropin treatment for male partial congenital hypogonadotropic hypogonadism in Chinese patients.

Partial congenital hypogonadotropic hypogonadism (PCHH) is caused by an insufficiency in, but not a complete lack of, gonadotropin secretion. This leads to reduced testosterone production, mild testicular enlargement, and partial pubertal development. No studies have shown the productivity of spermatogenesis in patients with PCHH. We compared the outcomes of gonadotropin-induced spermatogenesis between patients with PCHH and those with complete congenital hypogonadotropic hypogonadism (CCHH). This retrospective study included 587 patients with CHH who were treated in Peking Union Medical College Hospital (Beijing, China) from January 2008 to September 2016. A total of 465 cases were excluded from data analysis for testosterone or gonadotropin-releasing hormone treatment, cryptorchidism, poor compliance, or incomplete medical data. We defined male patients with PCHH as those with a testicular volume of ≥4 ml and patients with a testicular volume of <4 ml as CCHH. A total of 122 compliant, noncryptorchid patients with PCHH or CCHH received combined human chorionic gonadotropin and human menopausal gonadotropin and were monitored for 24 months. Testicular size, serum luteinizing hormone levels, follicle-stimulating hormone levels, serum total testosterone levels, and sperm count were recorded at each visit. After gonadotropin therapy, patients with PCHH had a higher spermatogenesis rate (92.3%) than did patients with CCHH (74.7%). During 24-month combined gonadotropin treatment, the PCHH group took significantly less time to begin producing sperm compared with the CCHH group (median time: 11.7 vs 17.8 months, P < 0.05). In conclusion, after combined gonadotropin treatment, patients with PCHH have a higher spermatogenesis success rate and sperm concentrations and require shorter treatment periods for sperm production.

Eight rare urinary disorders in a patient with Kallmann syndrome: A case report.

RATIONALE: Kallmann syndrome (KS) is a rare inherited genetic disorder characterized by hypogonadotropic hypogonadism and hyposmia/anosmia. Early diagnosis is the key to timely treatment and improvement of prognosis in patients with KS. As the most common complication of KS, renal agenesis can provide clues to early diagnosis and treatment for KS. In this article, we report a case of KS with 8 rare urinary disorders for the first time. PATIENT CONCERNS: A 19-year-old Chinese man presented with 8 rare urinary disorders and a history of bilateral cryptorchidism came to us for micropenis, hyposmia, and delayed puberty. DIAGNOSIS: The patient presented with hyposmia, low levels of sex hormones and showed a weak response to the GnRH stimulation test leading to a diagnosis of KS. Two missense mutations were found in further whole-exome sequencing: 1) Kallmann syndrome 1 (KAL1) gene in exon11, c.1600G > A, p. Val534Ile; 2) Prokineticin receptor 2 (PROKR2) gene in exon 2, c.533G > A, p. Trp178Ser. which led to a diagnosis of KS. INTERVENTIONS: The patient underwent replacement therapy of human chorionic gonadotropin (HCG) and human menopausal gonadotropin (HMG). The patient had previously undergone six surgeries for cryptorchidism and urinary disorders. OUTCOMES: The patient's puberty retardation was effectively alleviated. His serum testosterone (T) reached a normal level (8.280 nmol/mL). During the follow-up period, he presented with Tanner stage II pubic hair development. CONCLUSION: In this article, we report 8 rare urinary disorders with missense mutations of KAL1 and PROKR2 in a case of KS. Among them, bilateral giant kidneys, urinary extravasation of right renal, bilateral megalo-ureters, left ureteral terminal obstruction, bilateral renal cyst and bladder emptying disorder are reported for the first time, which enrich the integrity of urinary disorder types and provide clues to genetic counseling in patients with KS.

[Kallmann-de Morsier syndrome: about 3 cases]. / Le syndrome de Kallmann-de Morsier: à propos de trois cas.

Kallmann-de Morsier syndrome (KS) is a genetic disease of the olfactory system characterized by the association of hypogonadotropic hypogonadism also referred to as gonadotropin-releasing hormone (GnRH) deficiency and anosmia or hyposmia (with hypoplasia or aplasia of the olfactory bulbs). Apart from sporadic cases that occur most often, familial Kallmann's syndrome is being described with increasing frequency. Diagnosis is mainly made in adolescents with absence of spontaneous puberty associated with smell disorders with hypoplasia or even aplasia of the bulbs and/or of the olfactory lobes on MRI. Sometimes, the diagnosis may be suspected in early childhood due to the association of cryptorchidism and micropénis. A mutation in one of known genes is only found in less than 30% of cases and, therefore, many other genes are still to be found. Hormone therapy allows pubertal growth in all cases and fertility can be obtained in most of the cases. We here report 3 cases of patients with this syndrome.

A review of Kallmann syndrome: genetics, pathophysiology, and clinical management.

Kallmann syndrome is a genetic disorder with the hallmarks of anosmia and hypogonadotrophic hypogonadism. It has a male preponderance. With the elucidation of the genetic pathways involved, affected females and inheritance patterns are becoming more clearly identified. It is an eminently treatable disorder, but it must first be recognized by the physician. With treatment, favorable reproductive outcomes can be attained in addition to maturation of secondary sex characteristics.