Magnetic Resonance Imaging Findings in Kallmann Syndrome: 14 Cases and Review of the Literature

A Review of Brain and Pituitary Gland MRI Findings in Patients with Ataxia and Hypogonadism

The association of cerebellar ataxia and hypogonadism occurs in a heterogeneous group of disorders, caused by different genetic mutations often associated with a recessive inheritance. In these patients, magnetic resonance imaging (MRI) plays a pivotal role in the diagnostic workflow, with a variable involvement of the cerebellar cortex, alone or in combination with other brain structures. Neuroimaging involvement of the pituitary gland is also variable. Here, we provide an overview of the main clinical and conventional brain and pituitary gland MRI imaging findings of the most common genetic mutations associated with the clinical phenotype of ataxia and hypogonadism, with the aim of helping neuroradiologists in the identification of these disorders.

Reconsidering the olfactory and brain structures in Kallmann's syndrome: New findings in the analysis of volumetry

OBJECTIVE

Kallmann's syndrome (KS) is characterized by hypogonadotropic hypogonadism and olfactory disorders. The complementary exams for evaluating of patients with hypogonadotrophic hypogonadism are important for the diagnosis and management of these patients.

PATIENTS

We performed a well-established olfactory Sniffin' Stick test (SST) on 17 adult patients with KS and brain magnetic resonance imaging (MRI) to evaluate olfactory structures and further analysis by Freesurfer, a software for segmentation and volumetric evaluation of brain structures. We compared the Freesurfer results with 34 healthy patients matched for age and sex and performed correlations between the data studied.

RESULTS

More than half of the patients with KS reported preserved smell but had olfactory disorders in the SST. In the MRI, 16 patients showed changes in the olfactory groove, the olfactory bulb-tract complex was altered in all of them and 52% had symmetrical structural changes. Interestingly, the pituitary gland was normal in only 29%. Regarding correlations, symmetrical changes in the olfactory structures were related to anosmia in 100%, while asymmetric changes induced anosmia in only 50% (p = .0294). In Freesurfer's assessment, patients with KS, compared to controls, had lower brainstem volume. In those with aplastic anterior olfactory sulcus, the brainstem volume was lower than in hypoplasia (p = .0333).

CONCLUSIONS

Olfactory assessment and MRI proved to be important auxiliary tools for the diagnosis and management of patients with KS. New studies are needed to confirm the decrease in brainstem volume found by the Freesurfer software in patients with KS. Further studies are needed to confirm the decrease in brainstem volume found by the Freesurfer software in patients with KS.

ACR Appropriateness Criteria® Cranial Neuropathy: 2022 Update

Cranial neuropathy can result from pathology affecting the nerve fibers at any point and requires imaging of the entire course of the nerve from its nucleus to the end organ in order to identify a cause. MRI with and without intravenous contrast is often the modality of choice with CT playing a complementary role. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer-reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Biology of human melanocyte development, Piebaldism, and Waardenburg syndrome

Melanocyte development is orchestrated by a complex interconnecting regulatory network of genes and synergistic interactions. Piebaldism and Waardenburg syndrome are neurocristopathies that arise from mutations in genes involved in this complex network. Our understanding of melanocyte development, Piebaldism, and Waardenburg syndrome has improved dramatically over the past decade. The diagnosis and classification of Waardenburg syndrome, first proposed in 1992 and based on phenotype, have expanded over the past three decades to include genotype. This review focuses on the current understanding of human melanocyte development and the evaluation and management of Piebaldism and Waardenburg syndrome. Management is often challenging and requires a multidisciplinary approach.

[Clinical and genetic features of Kallmann syndrome: an analysis of 5 cases]

Kallmann syndrome (KS) is a rare pediatric disease with major manifestations of olfactory dysfunction and hypogonadotropic hypogonadism. Five children (4 boys and 1 girl) with KS reported in this article were aged between 6 months and 19 years at the time when they attended the hospital. All the children had the clinical manifestation of hypogonadotropic hypogonadism; in addition, three children had olfactory dysfunction (two were found to have olfactory bulb dysplasia on magnetic resonance imaging), one had cleft lip and palate, and one had micropenis and cryptorchidism with right renal agenesis during infancy. All the five children had normal karyotype and their parents had normal clinical phenotypes. The uncle of one child had underdeveloped secondary sexual characteristics and olfactory disorder since childhood. High-throughput sequencing found two known heterozygous missense mutations in the FGFR1 gene, i.e., c.1097C>T(p.P366L) and c.809G>C(p.G270A), in two children. One child had a novel frameshift mutation, c.1877_1887/p.S627Tfs*6, in the KAL1 gene; this deletion mutation caused a frameshift in base sequence and produced truncated proteins, which led to a significant change in protein structure, and thus it was highly pathogenic. It is concluded that KS has great clinical and genetic heterogeneity and can be accompanied by incomplete dominant inheritance and that gene detection helps with the diagnosis of this disease.

Pediatric anosmia: A case series

INTRODUCTION

Little is known about the etiology of olfactory dysfunction in the pediatric population. The aim of this study is to characterize the etiology and clinical features of anosmia and to explore evaluation options in a pediatric population.

METHODS

Olfactory dysfunction was identified at a tertiary pediatric hospital between January 2003 and October 2014 using a text-based and ICD-9 search of the electronic health record system. Clinical information gathered included history, physical examination and imaging study. A phone questionnaire was completed to determine persistence and development of other rhinologic, endocrine, or neurologic symptoms.

RESULTS

37 children (male/female = 17/20) with mean/median ages of 13.28/14. 19 years were identified. The distribution of etiology was: rhinologic disease (N = 16), congenital (N = 4), trauma (N = 1), neoplasm (N = 1) and unknown (N = 15). Rhinologic disease included chronic rhinosinusitis (N = 3) and other nasal anatomic lesions. None of the four subjects with congenital anosmia had classic Kallmann syndrome. The utility of imaging in confirming an etiology of anosmia was noted in 1 of 8 CT and 5 of 22 MRI. The most significant finding of the questionnaire was confirmation of normal puberty in the congenital group.

CONCLUSION

Similar to the adult population, rhinologic disease is the most common cause. Absence or hypoplasia of the olfactory bulbs without associated delayed puberty is the presentation of congenital anosmia in our cohort. MRI had a higher utility than CT in evaluating anosmia in general and congenital anosmia in specific. MRI to evaluate children with a history of congenital olfactory dysfunction is recommended.

A case of Kallmann syndrome associated with a non-functional pituitary microadenoma

Kallmann syndrome (KS) is a form of hypogonadotropic hypogonadism in combination with a defect in sense of smell, due to abnormal migration of gonadotropin-releasing hormone-producing neurons. We report a case of a 17-year-old Tunisian male who presented with eunuchoid body proportions, absence of facial, axillary and pubic hair, micropenis and surgically corrected cryptorchidism. Associated findings included anosmia. Karyotype was 46XY and hormonal measurement hypogonadotropic hypogonadism. MRI of the brain showed bilateral agenesis of the olfactory bulbs and 3.5 mm pituitary microadenoma. Hormonal assays showed no evidence of pituitary hypersecretion.

Clinical characteristics of 138 Chinese female patients with idiopathic hypogonadotropic hypogonadism

OBJECTIVE

To evaluate the clinical features of Chinese women with idiopathic hypogonadotropic hypogonadism (IHH).

METHODS

We retrospectively reviewed the clinical characteristics, laboratory and imaging findings, therapeutic management and fertility outcomes of 138 women with IHH. All patients had been treated and followed up at an academic medical centre during 1990-2016.

RESULTS

Among the 138 patients, 82 patients (59.4%) were diagnosed with normosmic IHH and 56 patients (40.6%) were diagnosed with Kallmann syndrome (KS). The patients with IHH experienced occasional menses (4.3%), spontaneous thelarche (45.7%) or spontaneous pubarche (50.7%). Women with thelarche had a higher percentage of pubarche (P  < 0.001) and higher gonadotropin concentrations (P  < 0.01). Olfactory bulb/sulci abnormalities were found during the magnetic resonance imaging (MRI) of all patients with KS. Most patients with IHH had osteopenia and low bone age. Among the 16 women who received gonadotropin-releasing hormone treatment, ovulation induction or assisted reproductive technology, the clinical pregnancy rate was 81.3% and the live birth rate was 68.8%.

CONCLUSIONS

The present study revealed that the phenotypic spectrum of women with IHH is broader than typical primary amenorrhoea with no secondary sexual development, including occasional menses, spontaneous thelarche or pubarche. MRI of the olfactory system can facilitate the diagnosis of KS. Pregnancy can be achieved after receiving appropriate treatment.

A Case of Male Osteoporosis: A 37-Year-Old Man with Multiple Vertebral Compression Fractures

While the contributing role of testosterone to bone health is rather modest compared to other factors such as estradiol levels, male hypogonadism is associated with low bone mass and fragility fractures. Along with stimulating physical puberty by achieving virilization and a normal muscle mass and improving psychosocial wellbeing, the goals of testosterone replacement therapy in male hypogonadism also include attainment of age-specific bone mineral density. We report on a 37-year-old man who presented with multiple vertebral compression fractures several years following termination of testosterone replacement therapy for presumed constitutional delay in growth and puberty. Here, we discuss the management of congenital hypogonadotropic hypogonadism with hyposmia (Kallmann syndrome), with which the patient was ultimately diagnosed, the role of androgens in the acquisition of bone mass during puberty and its maintenance thereafter, and outline specific management strategies for patients with hypogonadism and high risk for fragility fractures.

Prognosis of Olfactory Dysfunction according to Etiology and Timing of Treatment

Objective We evaluated the severity of olfactory impairment according to risk factors, compared responses with risk factors and treatment timing, and investigated prognosis according to treatments. Study design Case series with chart review. Setting Tertiary referral center. Subjects and Methods We retrospectively reviewed medical records of patients complaining of loss of their sense of smell between January 2006 and May 2016. In total, 491 patients were included. We evaluated olfactory function using the Connecticut Chemosensory Clinical Research Center test (threshold test) and Cross-cultural Smell Identification Test. Results Post-upper respiratory infection patients showed better results than those with other risk factors (59.6% recovered). Patients with head trauma (12.5% recovered) and congenital olfactory dysfunction (0% recovered) showed poorer results. Earlier treatment showed better olfactory recovery outcomes for post-upper respiratory infection ( P = .001), head trauma ( P = .022), and nasal/sinus surgery ( P = .009). Xerostomia ( P = .73) and idiopathy ( P = .365) showed no significant difference in terms of treatment timing. The threshold test better reflected subjective recovery than the identification test. The systemic + topical steroid group and the systemic steroid treatment group both showed better smell recovery outcomes than the group with topical treatment alone (both, P < .001). However, there was no significant difference between the systemic treatment group and the systemic + topical treatment group ( P = .978). Conclusions Our findings suggest that the duration of smell loss is important for better olfactory outcomes with most etiologies. Also, the effects of systemic steroids were better than those of topical steroids, regardless of combined treatment.

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.