The syndrome of anosmia with hypogonadotropic hypogonadism: a genetic study of 18 new families and a review

Biallelic PROKR2 variants and congenital hypogonadotropic hypogonadism: a case report and a literature review

Congenital hypogonadotropic hypogonadism (CHH) is a rare disorder that causes gonadotropin-releasing hormone (GnRH) deficiency and sexual immaturity. CHH may accompany an abnormal sense of smell (Kallmann syndrome, KS) or no such manifestation (normosmic-CHH). This unusual combination of manifestations is explained by the fact that GnRH neurons originate in the olfactory placode and migrate to the forebrain during embryogenesis. We describe the case of a 31-year-old man with normosmic-CHH, who also had obesity, type 2 diabetes and intellectual disability. He was noticed to have sexual immaturity (small testes with no pubic hair) at age 20 years, when diabetic ketoacidosis developed. Basal and GnRH-stimulated levels of LH (1.0→12.0 IU/L) and FSH (1.9→6.1 IU/L) were detectable but low. The results of the T&T olfactometer and the Alinamin test were definitely normal, with an anatomically normal olfactory system on MRI. Sequencing of 22 CHH-related genes was performed, and compound heterozygous PROKR2 variants were identified: one was a previously known loss-of-function variant (p.Trp178Ser) and the other was a nonsense variant (p.Trp212*). Through a literature review, we found 22 patients (including our patient) with CHH due to biallelic PROKR2 variants, which led us to recognize that most of the patients (86%) were diagnosed with KS. Clinical observations in this study indicate that, even though they have CHH, biallelic PROKR2 variant carriers may have a normal olfactory system as well as presumably normal migration of GnRH neurons. This suggests that the PROK2-PROKR2 pathway affects the function of GnRH neurons after their migration.

Evaluating CHARGE syndrome in congenital hypogonadotropic hypogonadism patients harboring CHD7 variants

PURPOSE

Congenital hypogonadotropic hypogonadism (CHH), a rare genetic disease caused by gonadotropin-releasing hormone deficiency, can also be part of complex syndromes (e.g., CHARGE syndrome). CHD7 mutations were reported in 60% of patients with CHARGE syndrome, and in 6% of CHH patients. However, the definition of CHD7 mutations was variable, and the associated CHARGE signs in CHH were not systematically examined.

METHODS

Rare sequencing variants (RSVs) in CHD7 were identified through exome sequencing in 116 CHH probands, and were interpreted according to American College of Medical Genetics and Genomics guidelines. Detailed phenotyping was performed in CHH probands who were positive for CHD7 RSVs, and genotype-phenotype correlations were evaluated.

RESULTS

Of the CHH probands, 16% (18/116) were found to harbor heterozygous CHD7 RSVs, and detailed phenotyping was performed in 17 of them. Of CHH patients with pathogenic or likely pathogenic CHD7 variants, 80% (4/5) were found to exhibit multiple CHARGE features, and 3 of these patients were reclassified as having CHARGE syndrome. In contrast, only 8% (1/12) of CHH patients with nonpathogenic CHD7 variants exhibited multiple CHARGE features (P = 0.01).

CONCLUSION

Pathogenic or likely pathogenic CHD7 variants rarely cause isolated CHH. Therefore a detailed clinical investigation is indicated to clarify the diagnosis (CHH versus CHARGE) and to optimize clinical management.

On the mechanism of smell loss in patients with Type II congenital hyposmia

BACKGROUND

Smell function has been initiated with theophylline treatment in 63% of patients with Type II congenital smell loss. Based upon a systematic evaluation of the protein components of nasal mucus we have demonstrated that interactions among four chemical moieties in nasal mucus may play significant roles in this initiation. Prior to treatment three of these moieties, cAMP, cGMP and sonic hedgehog (Shh), were significantly decreased in concentration whereas one of these moieties, TNFalpha, was increased in concentration. The mechanism(s) responsible for initiation of smell function in these patients, not immediately apparent, may depend upon understanding interactions among these moieties.

METHODS

Measurements of cAMP, cGMP, Shh and TNFalpha in nasal mucus by specific spectrophotometric immunoassays before and after treatment with theophylline.

RESULTS

Before theophylline treatment cAMP, cGMP and Shh in nasal mucus, which act as growth factors to support olfactory receptor function, were significantly decreased below normal levels whereas TNFalpha which acts as a "death factor" to inhibit olfactory receptor function was significantly increased above normal. After theophylline treatment cAMP, cGMP and Shh increased significantly whereas TNFalpha decreased significantly.

CONCLUSIONS

These results indicate that there are specific biochemical changes associated with smell loss in patients with Type II congenital smell loss and that correction of these biochemical changes are associated with initiation of smell function in these patients. Understanding these relationships play an important role in understanding receptor action in smell function.

Erythrocyte membrane antigen frequencies in patients with Type II congenital smell loss

OBJECTIVE

The objective of this study was to determine whether there are genetic factors associated with Type II congenital smell loss.

STUDY DESIGN

The expression frequencies of 16 erythrocyte antigens among patients with Type II congenital smell loss were determined and compared to those of a large control group.

METHODS

Blood samples were obtained from 99 patients with Type II congenital smell loss. Presence of the erythrocyte surface antigens A, B, M, N, S, s, Fy(a), Fy(b), D, C, c, E, e, K, Jk(a), and Jk(b) was analyzed by blood group serology. Comparisons of expression frequencies of these antigens were made between the patients and a large control group.

RESULTS

Patients tested for the Duffy b antigen (Fy(b) haplotype) exhibited a statistically significant 11% decrease in expression frequency compared to the controls. There were no significant differences between patients and controls in the expression frequencies for all other erythrocyte antigens (A, B, M, N, S, s, Fy(a), D, C, c, E, e, K, Jk(a), or Jk(b)).

CONCLUSIONS

These findings describe the presence of a previously unrevealed genetic tendency among patients with Type II congenital smell loss related to erythrocyte surface antigen expression. The deviation in expression rate of Duffy b suggests a target gene and chromosome region in which future research into this form of congenital smell loss may reveal a more specific genetic basis for Type II congenital smell loss.

Invertebrate models of kallmann syndrome: molecular pathogenesis and new disease genes

Kallmann Syndrome is a heritable disorder characterized by congenital anosmia, hypogonadotropic hypogonadism and, less frequently, by other symptoms. The X-linked form of this syndrome is caused by mutations affecting the KAL1 gene that codes for the extracellular protein anosmin-1. Investigation of KAL1 function in mice has been hampered by the fact that the murine ortholog has not been identified. Thus studies performed in other animal models have contributed significantly to an understanding of the function of KAL1. In this review, the main results obtained using the two invertebrate models, the nematode worm Caenorhabditis elegans and the fruit fly Drosophila melanogaster, are illustrated and the contribution provided by them to the elucidation of the molecular pathogenesis of Kallmann Syndrome is discussed in detail. Structure-function dissection studies performed in these two animal models have shown how the different domains of anosmin-1 carry out specific functions, also suggesting a novel intramolecular regulation mechanism among the different domains of the protein. The model that emerges is one in which anosmin-1 plays different roles in different tissues, interacting with different components of the extracellular matrix. We also describe how the genetic approach in C. elegans has allowed the discovery of the genes involved in KAL1-heparan sulfate proteoglycans interactions and the identification of HS6ST1 as a new disease gene.

Mutations in FGF17, IL17RD, DUSP6, SPRY4, and FLRT3 are identified in individuals with congenital hypogonadotropic hypogonadism

Congenital hypogonadotropic hypogonadism (CHH) and its anosmia-associated form (Kallmann syndrome [KS]) are genetically heterogeneous. Among the >15 genes implicated in these conditions, mutations in FGF8 and FGFR1 account for ~12% of cases; notably, KAL1 and HS6ST1 are also involved in FGFR1 signaling and can be mutated in CHH. We therefore hypothesized that mutations in genes encoding a broader range of modulators of the FGFR1 pathway might contribute to the genetics of CHH as causal or modifier mutations. Thus, we aimed to (1) investigate whether CHH individuals harbor mutations in members of the so-called "FGF8 synexpression" group and (2) validate the ability of a bioinformatics algorithm on the basis of protein-protein interactome data (interactome-based affiliation scoring [IBAS]) to identify high-quality candidate genes. On the basis of sequence homology, expression, and structural and functional data, seven genes were selected and sequenced in 386 unrelated CHH individuals and 155 controls. Except for FGF18 and SPRY2, all other genes were found to be mutated in CHH individuals: FGF17 (n = 3 individuals), IL17RD (n = 8), DUSP6 (n = 5), SPRY4 (n = 14), and FLRT3 (n = 3). Independently, IBAS predicted FGF17 and IL17RD as the two top candidates in the entire proteome on the basis of a statistical test of their protein-protein interaction patterns to proteins known to be altered in CHH. Most of the FGF17 and IL17RD mutations altered protein function in vitro. IL17RD mutations were found only in KS individuals and were strongly linked to hearing loss (6/8 individuals). Mutations in genes encoding components of the FGF pathway are associated with complex modes of CHH inheritance and act primarily as contributors to an oligogenic genetic architecture underlying CHH.

Genetic basis and variable phenotypic expression of Kallmann syndrome: towards a unifying theory

Idiopathic hypogonadotropic hypogonadism (IHH) is defined by absent or incomplete puberty and characterised biochemically by low levels of sex steroids, with low or inappropriately normal gonadotropin hormones. IHH is frequently accompanied by non-reproductive abnormalities, most commonly anosmia, which is present in 50-60% of cases and defines Kallmann syndrome. The understanding of IHH has undergone rapid evolution, both in respect of genetics and breadth of phenotype. Once considered in monogenic Mendelian terms, it is now more coherently understood as a complex genetic condition. Oligogenic and complex genetic-environmental interactions have now been identified, with physiological and environmental factors interacting in genetically susceptible individuals to alter the clinical course and phenotype. These potentially link IHH to ancient evolutionary pressures on the ancestral human genome.

The role of the prokineticin 2 pathway in human reproduction: evidence from the study of human and murine gene mutations

A widely dispersed network of hypothalamic GnRH neurons controls the reproductive axis in mammals. Genetic investigation of the human disease model of isolated GnRH deficiency has revealed several key genes crucial for GnRH neuronal ontogeny and GnRH secretion. Among these genes, prokineticin 2 (PROK2), and PROK2 receptor (PROKR2) have recently emerged as critical regulators of reproduction in both mice and humans. Both prok2- and prokr2-deficient mice recapitulate the human Kallmann syndrome phenotype. Additionally, PROK2 and PROKR2 mutations are seen in humans with Kallmann syndrome, thus implicating this pathway in GnRH neuronal migration. However, PROK2/PROKR2 mutations are also seen in normosmic GnRH deficiency, suggesting a role for the prokineticin signaling system in GnRH biology that is beyond neuronal migration. This observation is particularly surprising because mature GnRH neurons do not express PROKR2. Moreover, mutations in both PROK2 and PROKR2 are predominantly detected in the heterozygous state with incomplete penetrance or variable expressivity frequently seen within and across pedigrees. In some of these pedigrees, a "second hit" or oligogenicity has been documented. Besides reproduction, a pleiotropic physiological role for PROK2 is now recognized, including regulation of pain perception, circadian rhythms, hematopoiesis, and immune response. Therefore, further detailed clinical studies of patients with PROK2/PROKR2 mutations will help to map the broader biological role of the PROK2/PROKR2 pathway and identify other interacting genes/proteins that mediate its molecular effects in humans.

Clues to an early diagnosis of Kallmann syndrome

Kallmann syndrome (KS) is defined by the association of idiopathic hypogonadotropic hypogonadism and anosmia/hyposmia. Diagnosis is frequently delayed, however, because hypogonadotropic hypogonadism is usually not apparent until puberty and individuals with anosmia/hyposmia are often unaware of this sensory deficit. Mutations in at least six genes have been associated with KS; however, the sensitivity of molecular testing is only about 30% and, therefore, the diagnosis is largely based on clinical findings. We describe the findings in six individuals with KS, which demonstrate the utility of associated anomalies in making this diagnosis. Analysis of our case series and literature review suggests the consideration of KS for males with microphallus and/or cryptorchidism and for any patient with hearing loss, renal agenesis, and/or synkinesis. Conversely, patients with features of KS should have an audiology evaluation and a renal ultrasound.

Genetics basis for GnRH-dependent pubertal disorders in humans

Human puberty is triggered by the reemergence of GnRH pulsatile secretion, with progressive activation of gonadal function. Several mutations have been identified in an increasing number of genes that influence the onset of puberty. Mutations in GNRH1, KISS1R and GNRHR genes cause normosmic IHH, interfering with the normal synthesis, secretion or action of GnRH. More recently, mutations in TAC3 and TACR3 genes, which encode neurokinin B and its receptor, have been implicated in normosmic IHH, although their precise functions in reproduction remain unclear. Mutations in KAL1, FGFR1, FGF8, PROK2 and PROKR2 are related to disruption of the development and migration of GnRH neurons, thereby resulting in Kallmann syndrome, a complex genetic condition characterized by isolated hypogonadotropic hypogonadism (IHH) and olfactory abnormalities. Furthermore, mutations in CHD7 gene, a major gene involved in the etiology of CHARGE syndrome, were also described in some patients with Kallmann syndrome and normosmic IHH. Notably, the evidence of association of some of the genes implicated with GnRH neurons development and migration with both Kallmann syndrome and normosmic IHH, blurring the simplest clinical distinction between ontogenic and purely functional defects in the axis. Digenic or oligogenic inheritance of IHH has also been described, illustrating the extraordinary genetic heterogeneity of IHH. Interestingly, rare gain-of-function mutations of the genes encoding the kisspeptin and its receptor were recently associated with central precocious puberty phenotype, indicating that the premature activation of the reproductive axis may be also caused by genetic mutations. These discoveries have yielded significant insights into the current knowledge of this important life transition.

Clinical genetics of Kallmann syndrome

The Kallmann syndrome (KS) combines hypogonadotropic hypogonadism (HH) with anosmia. This is a clinically and genetically heterogeneous disease. KAL1, encoding the extracellular glycoprotein anosmin-1, is responsible for the X chromosome-linked recessive form of the disease (KAL1). Mutations in FGFR1 or FGF8, encoding fibroblast growth factor receptor-1 and fibroblast growth factor-8, respectively, underlie an autosomal dominant form with incomplete penetrance (KAL2). Mutations in PROKR2 and PROK2, encoding prokineticin receptor-2 and prokineticin-2, have been found in heterozygous, homozygous, and compound heterozygous states. These two genes are likely to be involved both in autosomal recessive monogenic (KAL3) and digenic/oligogenic KS transmission modes. Mutations in any of the above-mentioned KS genes have been found in less than 30% of the KS patients, which indicates that other genes involved in the disease remain to be discovered. Notably, KS may also be part of pleiotropic developmental diseases including CHARGE syndrome; this disease results in most cases from neomutations in CHD7 that encodes a chromodomain helicase DNA-binding protein.

Kallmann syndrome

The Kallmann syndrome (KS) combines hypogonadotropic hypogonadism (HH) with anosmia. This is a clinically and genetically heterogeneous disease. KAL1, encoding the extracellular glycoprotein anosmin-1, is responsible for the X chromosome-linked recessive form of the disease. Mutations in FGFR1 or FGF8, encoding fibroblast growth factor receptor-1 and fibroblast growth factor-8, respectively, underlie an autosomal dominant form with incomplete penetrance. Finally, mutations in PROKR2 and PROK2, encoding prokineticin receptor-2 and prokineticin-2, have been found in heterozygous, homozygous, and compound heterozygous states. These two genes are likely to be involved both in monogenic recessive and digenic/oligogenic KS transmission modes. Notably, mutations in any of the above-mentioned KS genes have been found in less than 30% of the KS patients, which indicates that other genes involved in the disease remain to be discovered.

Follicular development induced by recombinant luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in anovulatory women with LH and FSH deficiency: evidence of a threshold effect

OBJECTIVE

To assess the requirement for luteinizing hormone (LH) in women deficient in LH and follicle-stimulating hormone (FSH).

RESEARCH DESIGN AND METHODS

A prospective, randomized, parallel-group, multicentre study was carried out in tertiary care and academic medical centres. Women with anovulatory amenorrhoea > or = 1 year, serum oestradiol (E(2)) < 60 pg/mL (< 220 pmol/L) and low normal serum gonadotrophins were randomized in cycle A to a fixed daily dose of recombinant human (r-h) FSH (150 IU) and r-hLH 0, 25, 75 or 225 IU. Cycles B and C were not randomized.

MAIN OUTCOME MEASURES

Follicular development, ovulation and luteinization.

RESULTS

In cycle A, follicular development was achieved by 63.6% (7/11), 100% (9/9), 72.7% (8/11) and 66.7% (6/9) of patients who received r-hFSH and r-hLH 0, 25, 75 or 225 IU/day, respectively (p = not significant). Among patients with basal serum LH of < 1.2 IU/L, a dose-response relationship of r-hLH to follicular development was observed (p = 0.039). Fourteen of 34 patients (41.2%) wishing to conceive became pregnant. Among patients with hypogonadotrophic hypogonadism (HH) treated with r-hFSH alone, a transition from LH dependence to independence was observed between basal LH values of > or = 1.2 IU/L and < or = 1.6 IU/L. The r-hLH was well tolerated and no serious adverse events occurred during treatment. The most common treatment-related events were related to the reproductive system and the gastrointestinal tract.

CONCLUSIONS

Recombinant human LH provides a safe treatment option for women with HH. This small study also provided evidence suggestive of an LH threshold: follicular development was suboptimal when less than 75 IU/day r-hLH was administered.

Olfactory function in Australian aboriginal children and chronic otitis media

Chronic suppurative otitis media (CSOM), a severe form of middle ear infection, affects most Australian Aboriginal children with up to 50% in some communities suffering hearing loss as a consequence. To date, there is no information on whether repeated exposure to the pathogens that characterize CSOM and that are present in the upper respiratory airway affect olfactory function. Accordingly, this study aimed to determine whether 1) there was a high prevalence of olfactory loss in Aboriginal children and 2) hearing loss is a predictor of olfactory loss. Two hundred and sixty one 9- to 12-year-old Aboriginal children from 16 rural communities reported to have high prevalences of CSOM and hearing loss were assessed for olfactory loss using a 16-odor identification test and hearing loss. One child was found to be anosmic, 4 were slightly hyposmic, and 42 had hearing loss. No relationship was found between olfactory loss and hearing loss. The test-retest reliability of the 16-odor identification test was 0.98. It was concluded that CSOM does not appear to affect olfactory function in the long term and that hearing loss in Aboriginal children is not a predictor of olfactory loss.

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.

Cellular signaling by fibroblast growth factors (FGFs) and their receptors (FGFRs) in male reproduction

The major function of the reproductive system is to ensure the survival of the species by passing on hereditary traits from one generation to the next. This is accomplished through the production of gametes and the generation of hormones that function in the maturation and regulation of the reproductive system. It is well established that normal development and function of the male reproductive system is mediated by endocrine and paracrine signaling pathways. Fibroblast growth factors (FGFs), their receptors (FGFRs), and signaling cascades have been implicated in a diverse range of cellular processes including: proliferation, apoptosis, cell survival, chemotaxis, cell adhesion, motility, and differentiation. The maintenance and regulation of correct FGF signaling is evident from human and mouse genetic studies which demonstrate that mutations leading to disruption of FGF signaling cause a variety of developmental disorders including dominant skeletal diseases, infertility, and cancer. Over the course of this review, we will provide evidence for differential expression of FGFs/FGFRs in the testis, male germ cells, the epididymis, the seminal vesicle, and the prostate. We will show that this signaling cascade has an important role in sperm development and maturation. Furthermore, we will demonstrate that FGF/FGFR signaling is essential for normal epididymal function and prostate development. To this end, we will provide evidence for the involvement of the FGF signaling system in the regulation and maintenance of the male reproductive system.

Renal dysgenesis and KAL1 gene defects in patients with sporadic Kallmann syndrome

OBJECTIVE

To correlate the presence of renal agenesis/dysgenesis to the prevalence of KAL1 gene defects in patients with sporadic Kallmann syndrome (KS).

DESIGN

Prospective assessment of renal structure and DNA sequence analysis of the KAL1 gene.

SETTING

Outpatient clinics of the divisions of endocrinology of university hospitals.

PATIENT(S)

Sixteen male patients with sporadic KS.

INTERVENTION(S)

Assessment of renal structure by abdominal ultrasounds scans and DNA extraction, polymerase chain reaction amplification, and DNA sequence analysis of all 14 exons of the KAL1 gene.

MAIN OUTCOME MEASURE(S)

KAL 1 gene structure and presence of renal dysgenesis.

RESULT(S)

Renal dysgenesis was identified in only two of 16 KS patients. Genetic defects were found in only two patients with KS, that is, in those with the identified renal dysgenesis. The first gene defect was identified in a patient with associated right renal agenesis who had two point mutations in the KAL1 gene: the first was a G to A transition in exon 11, turning codon 514 encoding glutamic acid into lysine; and the second was a G to A transition in exon 13, turning codon 660 encoding alanine into threonine. The second gene defect was identified in a patient with ichthyosis, right renal agenesis, and mirror movements of the upper limbs (synkinesia) and comprised a deletion of exons 5-10 of the KAL1 gene and a complete deletion of the steroid sulphatase gene.

CONCLUSION(S)

The phenotype of renal agenesis/dysgenesis strongly indicates the existence of KAL1 gene defects in the genotype of patients with sporadic KS, providing evidence for the X-linked mode of inheritance and offering the opportunity for genetic counseling.

A genome-wide linkage scan for cleft lip and cleft palate identifies a novel locus on 8p11-23

Isolated or nonsyndromic cleft lip and palate (NS CLP) is a complex disorder resulting from multiple genetic and environmental factors. NS CLP has a birth prevalence of 1 per 500 in the Philippines where large families provide an opportunity for gene localization. Genotyping of 392 microsatellite repeat markers at 10 cM intervals over the genome was performed by the Center for Inherited Disease Research (CIDR) on 220 Filipino families with 567 affected and 1,109 unaffected family members genotyped. Among the most statistically significant results from analysis of the genome-wide scan data was a 20 cM region at 8p11-23 in which markers had LODs > or =1.0. This region on 8p11-23 has not been found in any previous genome wide scan nor does it contain any of the candidate genes widely studied in CLP. Fine mapping in 8p11-23 was done in the 220 families plus an additional 51 families, using SNP markers from 10 known genes (FGFR1, NRG1, FZD3, SLC8A1, PPP3CC, EPHX2, BNIP3L, EGR3, PPP2R2A, and NAT1) within the 20 cM region of 8p11-23. Linkage and association analyses of these SNPs yield suggestive results for markers in FGFR1 (recessive multipoint HLOD 1.07) and BAG4 (recessive multipoint HLOD 1.31).

Genetic insights into human isolated gonadotropin deficiency

The identification of naturally occurring genetic mutations has provided unique insight into the current knowledge of the human hypothalamic-pituitary-gonadal axis. In the past decade, several monogenic causes have been reported in patients with isolated gonadotropin deficiency. Kallmann Syndrome is a clinically and genetically heterogeneous disorder, characterized by isolated hypogonadotropic hypogonadism and anosmia or hyposmia. To date, loss-of-function mutations in the genes encoding anosmin-1 (KAL1) and fibroblast growth factor receptor 1 (FGFR1) have been described in the X-linked and autosomal dominant forms of this syndrome, respectively. More recently, several heterozygous, homozygous or compound heterozygous mutations in the G protein-coupled prokineticin receptor-2 (PROKR2) and one of its ligands, prokineticin-2 (PROK2) were described in Kallmann syndrome. In addition, complex genetic transmission (digenic inheritance) was recently demonstrated in this condition. Regarding isolated hypogonadotropic hypogonadism without olfactory abnormalities, loss-of-function mutations in the Gonadotropin-releasing hormone (GnRH) receptor (GnRH-R) or the G-protein coupled receptor 54 (GPR54) genes, both encoding transmembrane receptors, have been described, as well as FGFR1 mutations. Finally, mutations of the beta sub-units of LH and FSH have been described in patients with selective gonadotropin deficiency. We review the role of these distinct genetic factors in human isolated hypogonadotropic hypogonadism.

Atypical presentation of a patient with both kallmann syndrome and a craniopharyngioma: case report and literature review

OBJECTIVE

To describe an unusual presentation of a patient with Kallmann syndrome, without the typical eunuchoid features, who had additional hormonal abnormalities caused by a craniopharyngioma.

METHODS

This patient's clinical features, endocrine evaluation, and treatment are described, and the literature regarding Kallmann syndrome is reviewed. The expected phenotype of Kallmann syndrome is contrasted with this case presentation. A literature search was also performed to determine whether the combination of craniopharyngioma and Kallmann syndrome had been described previously.

RESULTS

A 23-year-old man had a suprasellar tumor in conjunction with hypogonadotropic hypogonadism and growth hormone deficiency. Subsequently, he was also noted to have anosmia, a cleft palate, and bilateral olfactory bulb hypoplasia. His height was less than his calculated midparental height and exceeded his arm span. Defective neuronal migration in Kallmann syndrome is caused by absence of adhesion proteins needed for cellular, neuronal, and axonal guidance. This results in failure of olfactory and gonadotropin-releasing hormone neurons to complete normal migration. Defective migration can also cause midline craniofacial abnormalities, renal agenesis, and cardiovascular defects. Arachnoid cysts have been reported in two patients with Kallmann syndrome, although whether a migration defect underlies their occurrence is speculative. No prior reports of craniopharyngioma in a patient with Kallmann syndrome could be identified.

CONCLUSION

It is postulated that although this patient had Kallmann syndrome, he did not present with a eunuchoid body habitus because of concomitant growth hormone deficiency caused by his craniopharyngioma. Although midline craniofacial abnormalities have been seen in patients with Kallmann syndrome, this patient's craniopharyngioma seems more likely to be coincidental, rather than being one of the developmental anomalies that are part of the spectrum of this syndrome.

Coexistence of Kallmann syndrome and complete androgen insensitivity in the same patient

Kallmann syndrome (KS) is a developmental disease that combines hypogonadotropic hypogonadism and anosmia/hyposmia. Other congenital abnormalities may also coexist. This present report describes two sisters, aged 13 and 12 years, born from Lebanese consanguineous parents. The two sisters have complete androgen insensitivity (normal female appearance and an XY karyotype) due to a novel mutation, a C-to-G transversion in intron 2 of the androgen receptor gene, resulting in an aberrant splicing leading to an insertion of 66 nucleotides in the mRNA. In addition, the older sister has KS, together with synkinesia and multiple skeletal abnormalities, mainly kyphosis, vertebral abnormalities, and short right hand and feet. Her testosterone, FSH and LH levels were very low compared with her younger sister. No mutation in the KAL1 and FGFR1/KAL2 genes were found. This unique report raises the possibility of an autosomal recessive or X-linked form of KS with new phenotypic expression.

The product of X-linked Kallmann's syndrome gene (KAL1) affects the migratory activity of gonadotropin-releasing hormone (GnRH)-producing neurons

X-linked Kallmann's syndrome (KS) is a genetic disease characterized by anosmia and hypogonadism due to impairment in the development of olfactory axons and in the migration of gonadotropin-releasing hormone (GnRH)-producing neurons. Deletions or point mutations of a gene located at Xp22.3 (KAL1) are responsible for the disease. This gene encodes for a secreted heparin-binding protein (KAL or anosmin-1) which exhibits similarities with cell-adhesion molecules. In the present study, we show for the first time a direct action of anosmin-1 on the migratory activity of GnRH neurons. Specifically, we exposed immortalized migrating GnRH neurons (GN11 cells) to conditioned media (CM) of COS or CHO cells transiently transfected with human KAL1 gene in microchemotaxis and collagen gel assays. We found that anosmin-1-enriched media produced a cell-specific chemotactic response of GN11 cells. None of the CM enriched on three forms of anosmin-1 carrying different missense mutations (N267K, E514K and F517L) found in patients affected by X-linked KS affected the chemomigration of GN11 cells. Anosmin binds to the GN11 cell surface by interacting with the heparan sulphate proteoglycans, and the chemotactic effect of anosmin-1-enriched CM can be specifically blocked by heparin or by heparitinase pretreatment. These results strongly suggest an involvement of anosmin-1 in the control of the migratory behaviour of GnRH neurons and provide novel information on the pathogenesis of KS.

Kallmann syndrome: fibroblast growth factor signaling insufficiency?

Kallmann syndrome (KAL) is a developmental disease that combines hypogonadotropic hypogonadism and anosmia. Anosmia is related to the absence or hypoplasia of the olfactory bulbs. Hypogonadism is due to GnRH deficiency and is likely to result from the failed embryonic migration of GnRH-synthesizing neurons. These cells normally migrate from the olfactory epithelium to the forebrain along the olfactory nerve pathway. KAL is phenotypically and genetically heterogeneous. The gene responsible for the X-chromosome linked form of the disease (KAL1) has been identified in 1991. KAL1 encodes anosmin-1, an approximately 95-kDa glycoprotein of unknown function which is present locally in various extracellular matrices during the period of organogenesis. The recent finding that FGFR1 mutations are involved in an autosomal dominant form of Kallmann syndrome (KAL2), combined with the analysis of mutant mouse embryos that no longer express Fgfr1 in the telencephalon, suggests that the disease results from a deficiency in FGF signaling at the earliest stage of olfactory bulb morphogenesis. We propose that the role of anosmin-1 is to enhance FGF signaling and suggest that the gender difference in anosmin-1 dose (because KAL1 partially escapes X-inactivation) explains the higher prevalence of the disease in males.

Aromatase inhibition for the treatment of idiopathic hypogonadotropic hypogonadism in men with premature ejaculation

BACKGROUND

Idiopathic hypogonadotropic hypogonadism (IHH) has been observed to occur in men with premature ejaculation (PE). Common IHH therapies include testosterone replacement, which increases testosterone levels but suppresses gonadotropin release; and gonadotropin-releasing hormone supplementation, which restores gonadotropin levels but is impractical for chronic use. Hormonal imbalances associated with IHH/PE are thought to be related to hyperactivity of the cytochrome P-450 enzyme aromatase.

METHODS

Ten male patients with a diagnosis of IHH/PE were treated with the aromatase inhibitor anastrazole (1 mg/d orally). Levels of free and total testosterone, luteinizing hormone, follicle-stimulating hormone, prolactin, and estradiol were determined at baseline and after 2 weeks of therapy.

RESULTS

After 2 weeks of therapy with anastrazole, levels of testosterone, luteinizing hormone, and estradiol had returned to normal. No effect was noted on premature ejaculation.

CONCLUSION

These results suggest that aromatase inhibition with anastrazole may provide a practical and efficacious alternative for the treatment of IHH but is not effective in preventing premature ejaculation.

Loss-of-function mutations in FGFR1 cause autosomal dominant Kallmann syndrome

We took advantage of overlapping interstitial deletions at chromosome 8p11-p12 in two individuals with contiguous gene syndromes and defined an interval of roughly 540 kb associated with a dominant form of Kallmann syndrome, KAL2. We establish here that loss-of-function mutations in FGFR1 underlie KAL2 whereas a gain-of-function mutation in FGFR1 has been shown to cause a form of craniosynostosis. Moreover, we suggest that the KAL1 gene product, the extracellular matrix protein anosmin-1, is involved in FGF signaling and propose that the gender difference in anosmin-1 dosage (because KAL1 partially escapes X inactivation) explains the higher prevalence of the disease in males.

The Kallmann syndrome gene homolog in C. elegans is involved in epidermal morphogenesis and neurite branching

Kallmann syndrome is an inherited disorder defined by the association of anosmia and hypogonadism, owing to impaired targeting and migration of olfactory axons and gonadotropin-releasing hormone secreting neurons. The gene responsible for the X-linked form of Kallmann syndrome, KAL-1, encodes a secreted protein of still elusive function. It has been proposed that KAL-1 might be involved in some aspects of olfactory axon guidance. However, the unavailability of a mouse model, and the difficulties in studying cellular and axonal migration in vertebrates have hampered an understanding of its function. We have identified the C. elegans homolog, kal-1, and document its function in vivo. We show that kal-1 is part of a mechanism by which neurons influence migration and adhesion of epidermal cells undergoing morphogenesis during ventral enclosure and male tail formation. We also show that kal-1 affects neurite outgrowth in vivo by modulating branching. Finally, we find that human KAL-1 cDNA can compensate for the loss of worm kal-1 and that overexpression of worm or human KAL-1 cDNAs in the nematode results in the same phenotypes. These data indicate functional conservation between the human and nematode proteins and establish C. elegans as a powerful animal in which to investigate KAL function in vivo. Our findings add a new player to the set of molecules, which appear to underlie both morphogenesis and axonal/neuronal navigation in vertebrates and invertebrates.

Functional MRI of congenital hyposmia: brain activation to odors and imagination of odors and tastes

PURPOSE

Our goal was to use functional MRI (fMRI) to define brain activation in response to odors and imagination ("memory") of odors and tastes in patients who never recognized odors (congenital hyposmia).

METHOD

Functional MR brain scans were obtained in nine patients with congenital hyposmia using multislice echo planar imaging (EPI) in response to odors of amyl acetate, menthone, and pyridine and to imagination ("memory") of banana and peppermint odors and to salt and sweet tastes. Functional MR brain scans were compared with those in normal subjects and patients with acquired hyposmia. Activation images were derived using correlation analysis, and ratios of areas of brain activated to total and hemispheric brain areas were calculated. Total and hemispheric activated pixel counts were used to quantitate regional brain activation.

RESULTS

Brain activation in response to odors was present in patients with congenital hyposmia. Activation was significantly lower than in normal subjects and patients with acquired hyposmia and did not demonstrate differential vapor pressure-dependent detection responsiveness or odor response lateralization. Regional activation localization was in anterior frontal and temporal cortex similar to that in normal subjects and patients with acquired hyposmia. Activation in response to presented odors was diverse, with a larger group exhibiting little or no activation with localization only in anterior frontal and temporal cortex and a smaller group exhibiting greater activation with localization extending to more complex olfactory integration sites. "Memory" of odors and tastes elicited activation in the same central nervous system (CNS) regions in which activation in response to presented odors occurred, but responses were significantly lower than in normal subjects and patients with acquired hyposmia and did not lateralize.

CONCLUSION

Odors induced CNS activation in patients with congenital hyposmia, which distinguishes olfaction from vision and audition since neither light nor acoustic stimuli induce CNS activation. Odor activation localized to anterior frontal and temporal cortex, consistent with the hypothesis that olfactory pathways are hard-wired into the CNS and that further pathways are undeveloped with primary olfactory system CNS connections but lack of secondary connections. However, some patients exhibited greater odor activation with response localization extending to cingulate and opercular cortex, indicating some olfactory signals impinge on and maintain secondary connections consistent with similar functions in vision and audition. Activation localization of taste "memory" to anterior frontal and temporal cortex is consistent with CNS plasticity and cross-modal CNS reorganization as described for vision and audition. Thus, there are differences and similarities between olfaction, vision, and audition, the differences dependent on unique qualities of olfaction, perhaps due to its diffuse, primitive, fundamental role in survival. Response heterogeneity to odors may reflect heterogeneous genetic abnormalities, independent of anatomic or hormonal changes but dependent on molecular abnormalities in growth factor function interfering with growth factor/stem cell interactions. Patients with congenital hyposmia offer an unique model system not previously explored in which congenital smell lack as measured by fMRI is reflective of congenital dysfunction of a major sensory system.

Kallmann syndrome: towards molecular pathogenesis

Gonadotropin Releasing Hormone (GnRH) is a key regulator of reproduction and sexual behaviour. During the last decade, embryological studies have clarified the question of the early development of GnRH-synthesising neurones before the onset of neurosecretion. These studies have revealed the existence of a topographical link between GnRH-synthesising neurones and the embryonic olfactory system, thereby shedding new light on Kallmann syndrome, a developmental disease characterised by the association of hypogonadotropic hypogonadism and anosmia (or hyposmia). Although Kallmann syndrome was identified as an inherited disease in the forties, familial cases of the disease are infrequent. However, the identification, by positional cloning strategies, of the gene underlying the X-chromosome linked form of the disease (KAL-1) has opened the way to molecular pathophysiology. KAL-1 encodes an extracellular glycoprotein of compound modular structure. The protein, named anosmin-1, has been produced in a transfected mammalian cell line and purified. Polyclonal and monoclonal antibodies have been generated, which allowed us to study the distribution of the protein during the period of human organogenesis (4--10 embryonic weeks), by immunohistofluorescence. During this developmental period, anosmin-1 is a locally restricted component of various extracellular matrices (interstitial matrices and basement membranes). Later in embryonic life, KAL-1 expression apparently becomes restricted to definite neuronal populations. Based on the distribution of anosmin-1 in the early olfactory system, the pathogenesis of the olfactory loss and GnRH deficiency in X-linked Kallmann syndrome is discussed.

A novel homozygous mutation in the second transmembrane domain of the gonadotrophin releasing hormone receptor gene

BACKGROUND AND OBJECTIVE

Mutations in the GnRH receptor (GnRH-R) gene cause hypogonadotrophic hypogonadism. Here, we present the molecular studies of the GnRH-R gene in three families with isolated hypogonadotrophic hypogonadism.

PATIENTS

Three unrelated families, with at least two members diagnosed with isolated hypogonadotrophic hypogonadism were included.

MEASUREMENTS

DNA sequencing was performed after polymerase chain reaction amplification of each of the three exons of the gene.

RESULTS

A novel homozygous missense mutation, at nucleotide 268, turning glutamic acid into lysine, located at the second transmembrane domain of the GnRH-R gene was found in two patients pertaining to one of the families studied. Both parents and an unaffected brother were heterozygous carriers of one mutant allele, an unaffected sister was homozygote wild type. In the other two affected families no mutations were found in the GnRH-R gene.

CONCLUSIONS

This constitutes the first description of an spontaneous mutation located at the second transmembrane domain (Glu90Lys) of the GnRH-R, indicating that the integrity of glutamic acid at this position is crucial for receptor function. Also this report, complementing others, demonstrates that mutations are distributed throughout the GnRH-R gene and that as in the only other homozygous mutation previously described, affected patients present a complete form of hypogonadotrophic hypogonadism. Due to the fact that apparently consanguinity was present in our affected family, we presume that the mutation derived from a common ancestor, by a founder gene effect.

Hypogonadotropic hypogonadism: retrospective analysis of 19 cases

OBJECTIVES

To survey the clinical data of patients with isolated gonadotropin deficiency.

METHODS

We retrospectively surveyed the medical records of 19 patients with isolated gonadotropin deficiency aged 16-31 years (mean: 20 years). The major complaint was primary amenorrhea in 100% of the patients, with 42.1% of them also reporting absence of secondary sex traits, and 10% reporting anosmia or hyposmia. Seventy-four percent of the patients had been submitted to hormonal replacement therapy.

RESULTS

Bone densitometry was determined in 5 patients and revealed lumbar spine osteopenia in 3 patients and femoral osteopenia in 1. An association with urologic malformations was detected in 10.5% of cases and an association with gynecologic malformations was detected in 31.6%.

CONCLUSIONS

Isolated gonadotropin deficiency can be easily diagnosed but requires early estrogen replacement therapy because of a higher risk of osteopenia and consequently of osteoporosis. Concomitant urogenital malformations are frequent and should be investigated.

Kallmann syndrome in three unrelated women and an association with femur-fibula-ulna dysostosis in one case

We describe three unrelated women with hypogonadotropic hypogonadism and anosmia; that is, Kallmann syndrome. Absence of olfactory bulbs and tracts and different degrees of asymmetric dysplasia of olfactory sulci were demonstrated by MRI. Both the father of Case 1 and the maternal aunt of Case 3 had anosmia, thus autosomal dominant inheritance seems to be likely. Patient 2 had Kallmann syndrome and FFU (femurfibula-ulna) dysostosis as a sporadic occurrence in her family.

Mutation analysis of the EMX2 gene in Kallmann's syndrome

OBJECTIVE

To investigate the possibility that a mutation in the human EMX2 gene may be involved in Kallmann's syndrome.

DESIGN

In vitro experiment.

SETTING

Academic Medical Center.

PATIENTS

One hundred and twenty patients with Kallman's syndrome or idiopathic hypogonadotrophic hypogonadism (IHH).

INTERVENTION

Peripheral blood leukocytes were used to obtain DNA.

MAIN OUTCOMES MEASURES

Single-stranded conformational polymorphism (SSCP) analysis was used to identify possible mutations of the EMX2 gene.

RESULTS

One hundred and twenty patients with Kallmann's syndrome or IHH, had no mutations noted in this gene.

CONCLUSION

It is unlikely that EMX2 mutations are a clinically significant cause of IHH or Kallman's syndrome.

Renal abnormalities in patients with Kallmann syndrome

OBJECTIVE

To report experience in patients with Kallmann syndrome (KS) in whom urography was used to establish the type and frequency of renal anomalies associated with the disorder.

PATIENTS AND METHODS

Of 19 patients with KS, 15 had the X-linked recessive form of the disease, whereas the remaining four were sporadic. Each patient underwent intravenous pyelography (IVP) using a non-ionic, low osmolarity contrast medium.

RESULTS

Of the 19 patients with KS, 10 had kidney abnormalities; four presented with unilateral renal agenesis and six had less severe forms of renal abnormality (renal malrotation in four and bilateral dilatation of the calyces and pelves in two). One of the patients with unilateral renal agenesis carried a deletion in KAL, the gene responsible for the X-linked type of KS. Three of the four patients with renal malrotation had a confirmed X-linked recessive form and one carried a point mutation in KAL.

CONCLUSION

These results suggest that kidney abnormalities are more frequent and diverse in patients with KS than previously reported. They also indicate that defects in the KAL gene may contribute to abnormal renal development. However, a review of the literature revealed no close correlation between KAL mutations and kidney anomalies in the X-linked type of disease. Taken together, these data suggest that KAL mutations are not invariably associated with failure of renal development and that additional factors (epigenetic or local) may compensate for defects in the KAL protein.

A recurrent missense mutation in the KAL gene in patients with X-linked Kallmann's syndrome

Kallmann's syndrome (KS) is defined by the association of hypogonadotropic hypogonadism and anosmia or hyposmia. Segregation analysis in familial cases has demonstrated diverse inheritance patterns, suggesting the existence of several genes regulating GnRH secretion. Genetic defects have been demonstrated in the KAL gene, located on the Xp22.3 region, explaining the X-linked form of the disease. We report molecular findings regarding the KAL gene in 12 unrelated males with X-linked KS. PCR of the 14 exons of the KAL gene was performed on genomic DNA. PCR products of all exons were purified and sequenced. Genetic defects in the KAL gene were found in 7 patients. One exhibits a deletion from exon 3 to exon 5. Six individuals present a previously unidentified missense mutation in exon 11, consisting of a G to A substitution at codon 514 (GAA to AAA). In the remaining 5 individuals, no mutations were observed. We also found three different polymorphic changes. The first one, in exon 2, had not been reported previously. The other two were located at exons 11 and 12. The deletion described, comprises only part (exon 5) of the coding region of the first fibronectin type III-like repeat of the KAL protein. The rest of the deletion comprises part of the conserved cysteine-rich N-terminal region that corresponds to the whey acidic protein motif. The same missense mutation was found in 6 of the 12 patients, indicating the possibility that it derived from a common ancestor or suggesting the presence of a hot spot in this region of the gene.

Craniofacial morphology in patients with Kallmann's syndrome with and without cleft lip and palate

OBJECTIVE

Kallmann's syndrome is characterized by the association of hypogonadotropic hypogonadism and anosmia or hyposmia. The principal endocrine defect of hypogonadotropic hypogonadism is a failure to secrete luteinizing hormone-releasing hormone (LHRH), resulting in underdevelopment of the pituitary gonadotropes and an inability to synthesize and release luteinizing hormone and follicle-stimulating hormone. The purpose of the present investigation was to describe the dentition and the craniofacial morphology in patients diagnosed with Kallmann's syndrome.

DESIGN

The sample consisted of 11 patients, 2 of whom also had bilateral cleft lip and palate. Radiographic investigations, including cephalometry, were performed. Comparisons were made to normal individuals and to cleft lip individuals without Kallmann's syndrome.

RESULTS

Dentition: tooth agenesis occurred more frequently in patients with Kallmann's syndrome. Craniofacial morphology: Increased mandibular inclination and mandibular angulation were seen in Kallmann patients. When clefting also occurred, extreme retrognathism of both maxilla and mandible was seen, a deviation which seemingly worsened during growth. The anterior cranial base and the sphenoid bone showed an altered morphology in one of the patients with Kallman's syndrome.

CONCLUSIONS

An early diagnosis of Kallmann's syndrome is very important because the prognosis for endocrine treatment thereby improves, and therefore, it is recommended that the sense of smell be evaluated in patients with the craniofacial morphology described.

Bilateral microphthalmia, esophageal atresia, and cryptorchidism: the anophthalmia-esophageal-genital syndrome

We report on a male infant with bilateral microphthalmia, esophageal atresia, and cryptorchidism. To our knowledge only 4 cases with a similar combination of congenital abnormalities have been previously reported, and it is likely that this represents a distinct entity. We suggest the name "anophthalmia-esophageal-genital-syndrome."

Luteinizing hormone-releasing hormone and innervation pathways in human prenatal nasal submucosa: factors of importance in evaluating Kallmann's syndrome

A previous study has demonstrated that luteinizing hormone-releasing hormone (LHRH) is localized in the human bilateral vomeronasal organs in the nasal septum during a 4-week period of intrauterine life (22). The purpose of the present study was to elucidate the location of LHRH-expressing cells outside the vomeronasal organs, with special emphasis on the submucosa of the medial wall and roof of the nasal cavity. An additional aim was to study the innervation pathways in the same regions. Both regions can be affected in Kallmann's syndrome, which is characterized by hypogonadotropic hypogonadism (lack of LHRH) and often associated with anosmia. Histological sections of craniofacial regions (49 normal human fetuses, 6-19 weeks) were examined by immunohistochemical techniques for LHRH and for neuronal tissue (protein gene product 9.5, PGP 9.5). LHRH reactions were only seen in the septal submucosa extending from the vomeronasal organs to the olfactory bulb. There was a close spatiotemporal association between the occurrence of LHRH and neuronal tissue. From the rhino-olfactory epithelium separate nerve tissue extended to the olfactory bulb. It is suggested that the medial region of the nasal placode giving rise to the septal wall is always affected in Kallmann's syndrome, and in cases in which the phenotypic features are associated with anosmia, also the more lateral part of the nasal placode, from which the rhino-olfactory region originates, is affected.

Variable penetrance of hypogonadism in a sibship with Kallmann syndrome due to a deletion of the KAL gene

We report on the clinical and molecular characterization of 3 sibs with X-linked ichthyosis and variable expression of Kallmann syndrome. One of the affected brothers had mild hyposmia and showed normal pubertal progression. However, we demonstrated the same partial deletion of the X-linked Kallmann gene, sparing the first exon in the mildly affected patient as well as in one of his severely affected brothers.

A molecular approach to the pathophysiology of the X chromosome-linked Kallmann's syndrome

The human KAL gene is responsible for the X chromosome-linked Kallmann's syndrome, which consists of an association between hypogonadotropic hypogonadism and anosmia (or hyposmia). Additional symptoms are occasionally observed. The olfactory defect is associated with hypoplasia of the olfactory bulbs and tracts. The hypogonadism may be due to a defect in the embryonic migratory process of GnRH-synthesizing neurones from the olfactory pits up to the brain. The human and chicken KAL genes have been isolated. From the amino acid sequences deduced, it has been postulated that the KAL protein is an extracellular matrix component, with putative antiprotease activity and adhesion function. Various point mutations and, in a few cases, deletions of KAL have been detected in patients. By in situ hybridization, KAL expression has been studied during embryonic development in the chick. From embryonic day 2 (ED2) to ED8, the KAL gene is expressed in various endodermal, mesodermal and ectodermal derivatives, whereas the expression from ED8 is almost entirely restricted to definite neuronal populations in the central nervous system, most of which still express the gene after hatching. According to such a spatiotemporal pattern of expression, we suggest that the KAL gene is involved both in morphogenetic events and in late neuronal differentiation and/or neuronal trophicity. With respect to the olfactory system, the KAL gene is expressed in the mitral cells of the olfactory bulbs from ED8 onwards. In contrast, no expression of the KAL gene is detected at any stage in either the embryonic olfactory epithelium or the surrounding nasal mesenchyme. Therefore, assuming that similar conditions are found in the human embryo, we suggest that the olfactory anomaly in X-linked Kallmann's syndrome results from a central target cell defect. Current hypotheses regarding the pathophysiology of the GnRH deficiency are also discussed. In situ hybridization experiments in the human embryo, as well as characterization of the KAL protein, are in progress.

Pregnancy in women with Kallmann's syndrome

OBJECTIVE

To induce of ovulation and pregnancy in women with Kallmann's syndrome.

DESIGN

Retrospective study.

PATIENTS

Three women with hypogonadotropic hypogonadism and anosmia with a desire for pregnancy.

INTERVENTIONS

Investigation of hypothalamic-pituitary-ovarian function and induction of ovulation by pulsatile GnRH or intramuscular human pituitary gonadotropins (hPG) or hMG with hCG.

MAIN OUTCOME MEASURES

Successful induction of ovulation as measured by serum P levels and successful pregnancy.

RESULTS

Ovulation was induced successfully in all three patients on more than one occasion and nine pregnancies occurred. Gonadotropin-releasing hormone was given IV by an electronically timed syringe driver. A total of 12 pulsatile GnRH cycles resulted in two pregnancies, 6 of these cycles being in one patient who did not ovulate or conceive with this therapy. Ovulation occurred in 10 of 16 hMG or hPG cycles, with conception in 7 of these. Gonadotropin usage was higher in these women compared with women with hypogonadotropic hypogonadism without anosmia (2,850 compared with 2,100 IU per treatment cycle), and the follicular phase was longer.

CONCLUSIONS

All three women conceived and had children after induction of ovulation. The success rate of these therapies in Kallmann's syndrome appears to be high in spite of very few reports in the literature.

Association of isolated hypogonadotropic hypogonadism, pronounced hypodontia and the Wolff-Parkinson-White syndrome

Diagnosis of idiopathic isolated hypogonadotropic hypogonadism was made in a 22-year-old female patient referred for primary amenorrhoea. It was considered a separate entity from Kallmann's syndrome, because it was not accompanied by anosmia or other specific pleiotropic features. On the other hand, the patient showed severe hypodontia and an intermittent Wolff-Parkinson-White syndrome. To our knowledge, this association has never been reported before. This unusual phenotype points to a nonrandom association. However, no information in the literature is available to consider a new single gene defect or a contiguous gene syndrome.

Diagnosis of X-recessive Kallmann syndrome in early infancy. Evidence of hypoplastic rhinencephalon

A 3-month-old infant presented with hypogonadism, a small penis and bilateral cryptorchidism. He showed an insufficient response of luteotropic hormone (LH) and follicle stimulating hormone (FSH) to luteotropic hormone releasing hormone (LHRH) and of testosterone to human chorionic gonadotropin. The maternal uncle had hypogonadism and anosmia and also showed an impaired LH and FSH response to LHRH. MRI examination showed hypoplasia of the rhinencephalon in both cases. These findings in the son and brother of the clinically unaffected mother suggest X-linked recessive inheritance.