Unilateral Focal Dermal Hypoplasia (Goltz Syndrome): Case Report and Literature Review

Amelogenesis imperfecta: Next-generation sequencing sheds light on Witkop's classification

Amelogenesis imperfecta (AI) is a heterogeneous group of genetic rare diseases disrupting enamel development (Smith et al., Front Physiol, 2017a, 8, 333). The clinical enamel phenotypes can be described as hypoplastic, hypomineralized or hypomature and serve as a basis, together with the mode of inheritance, to Witkop's classification (Witkop, J Oral Pathol, 1988, 17, 547-553). AI can be described in isolation or associated with others symptoms in syndromes. Its occurrence was estimated to range from 1/700 to 1/14,000. More than 70 genes have currently been identified as causative. Objectives: We analyzed using next-generation sequencing (NGS) a heterogeneous cohort of AI patients in order to determine the molecular etiology of AI and to improve diagnosis and disease management. Methods: Individuals presenting with so called "isolated" or syndromic AI were enrolled and examined at the Reference Centre for Rare Oral and Dental Diseases (O-Rares) using D4/phenodent protocol (www.phenodent.org). Families gave written informed consents for both phenotyping and molecular analysis and diagnosis using a dedicated NGS panel named GenoDENT. This panel explores currently simultaneously 567 genes. The study is registered under NCT01746121 and NCT02397824 (https://clinicaltrials.gov/). Results: GenoDENT obtained a 60% diagnostic rate. We reported genetics results for 221 persons divided between 115 AI index cases and their 106 associated relatives from a total of 111 families. From this index cohort, 73% were diagnosed with non-syndromic amelogenesis imperfecta and 27% with syndromic amelogenesis imperfecta. Each individual was classified according to the AI phenotype. Type I hypoplastic AI represented 61 individuals (53%), Type II hypomature AI affected 31 individuals (27%), Type III hypomineralized AI was diagnosed in 18 individuals (16%) and Type IV hypoplastic-hypomature AI with taurodontism concerned 5 individuals (4%). We validated the genetic diagnosis, with class 4 (likely pathogenic) or class 5 (pathogenic) variants, for 81% of the cohort, and identified candidate variants (variant of uncertain significance or VUS) for 19% of index cases. Among the 151 sequenced variants, 47 are newly reported and classified as class 4 or 5. The most frequently discovered genotypes were associated with MMP20 and FAM83H for isolated AI. FAM20A and LTBP3 genes were the most frequent genes identified for syndromic AI. Patients negative to the panel were resolved with exome sequencing elucidating for example the gene involved ie ACP4 or digenic inheritance. Conclusion: NGS GenoDENT panel is a validated and cost-efficient technique offering new perspectives to understand underlying molecular mechanisms of AI. Discovering variants in genes involved in syndromic AI (CNNM4, WDR72, FAM20A … ) transformed patient overall care. Unravelling the genetic basis of AI sheds light on Witkop's AI classification.

Focal Dermal Hypoplasia Associated With Lymphedema: A Case Report From Saudi Arabia

Focal dermal hypoplasia (FDH), also known as Goltz syndrome, is a rare syndrome described in the literature. Patchy skin hypoplasia is the most evident sign. Hyperpigmentation, hypopigmentation, papillomas, limb defects, and orofacial manifestations have also been reported. A 12-year-old Saudi girl with unremarkable family history presented with FDH. The diagnosis was confirmed using a genetic study. Physical examination revealed asymmetrical streaks of vermiculate dermal atrophy, telangiectasia with hyperpigmentation, and hypopigmentation on the left half of the face, trunk, and bilateral extremities. It appears along Blashko lines. No mental impairment was observed. Intraoral examination generalized plaque-induced gingivitis with erythematous gingival hyperplasia. Examination of the teeth showed generalized enamel hypoplasia with abnormal tooth formations, malalignment, microdontia, spacing and tilting, and minimal caries. As reported cases of FDH are rare worldwide, this syndrome is yet to be fully understood. As the manifestation of the syndrome varies among cases, the management of each case is unique. This emphasizes the importance of reporting cases of FDH.

Two new patients with focal dermal hypoplasia: A novel PORCN variant and insights on the diagnostic considerations

Mutations in the PORCN gene cause an X-linked dominant condition; focal dermal hypoplasia (FDH), characterized by atrophic skin, pigmented skin lesions in addition to several ocular and skeletal malformations. FDH is rare with around 275 cases reported so far from diverse ethnic groups. Herein, we provide a report of two new patients with FDH from Egypt. In addition to the typical clinical manifestations of the disease, infrequently reported clinical findings in the form of broad metaphysis, bilateral short broad femurs, and dermal sinus over the sacrum were seen in Patient 1 and partial fusion of labia majora, ventral hernia, and bladder extrophy were present in Patient 2. Two heterozygous protein-truncating PORCN mutations were identified in our patients, a known nonsense c.370C>T p.(Arg124Ter) and a novel frameshift c.375delG p.(Ala126HisfsTer3). Segregation analyses confirmed that the two mutations were "de novo" and not inherited from any of the parents. Our study expands the clinical and mutational spectrum of focal dermal hypoplasia and emphasizes the importance of investigating the different body systems and organs for the early management of patients.

Focal Dermal Hypoplasia (Goltz Syndrome): A Case Report Showing a Wide Variety of Systemic and Oral Manifestations

Focal dermal hypoplasia (FDH), also known as Goltz syndrome, consists of an unusual genodermatosis that affects tissues of ectodermal and mesodermal origin and various organs and systems, especially skin, bones, eyes, and oral cavity. While systemic manifestations of FDH have been well documented, the oral manifestations have not been extensively discussed. We present a 22-year-old female patient with history of FDH that showed a variety of systemic and oral manifestations. FDH was diagnosed at birth based on cutaneous alterations. Extra and intraoral examination showed facial asymmetry, lip and perioral atrophy, upper lip papilloma, malocclusion, enamel hypoplasia, and gingival hyperplasia. Mucosal lesions, periodontal diseases, and malocclusion were treated by oral surgery, periodontal therapy and orthodontic treatment, respectively. Although FDH is an uncommon syndrome, health professionals should be aware of its systemic and oral manifestations to establish an early diagnosis and adequate treatment.

A Rare Case of Mainly Unilateral Focal Dermal Hypoplasia (Goltz Syndrome) in an Adult Male: A Case Report and Review of the Literature

Focal dermal hypoplasia (Goltz syndrome), is an exceedingly rare X-linked dominant genetic disorder. It is a multisystem disease, but it is hallmarked by characteristic skin changes. Focal dermal hypoplasia typically occurs in females (90%), and males are thought to only survive through having either a sporadic new mutation or somatic mosaicism. This report details a 48-year-old male diagnosed with predominately unilateral focal dermal hypoplasia that was reviewed decades post his initial diagnosis. He presented with multiple atrophic hyperpigmented macules and fat herniation along the lines of Blaschko, across primarily the right side of the body. Skin biopsy is the mainstay for the diagnosis and therefore dermatologists need to be aware of the classical cutaneous findings of familial dermal hypoplasia to ensure accurate diagnosis. Familial dermal hypoplasia is best managed through the collective minds of multidisciplinary teams.

Microphthalmia and linear skin defects syndrome: Precise diagnosis guides prognosis

Microphthalmia and linear skin defects syndrome (MLS) is a rare X-linked dominant disorder characterized by microphthalmia and linear atrophic plaques of the face and neck. The diagnosis of MLS can be challenging secondary to both its rarity and to clinical overlap with Goltz syndrome. Whereas the skin lesions of MLS are more likely to improve in appearance with age, the lesions of Goltz are typically persistent.

Syndromes associated with dental agenesis

INTRODUCTION

Dental agenesis is the congenital absence of a variable number of teeth due to the lack of formation of the corresponding tooth germ. The aim of this work was to investigate the syndromic conditions characterized by dental agenesis.

EVIDENCE ACQUISITION

Based on the research conducted through the OMIM® (Online Mendelian Inheritance in Man) and PubMed online databases, more than ninety syndromes associated with severe or moderate agenesis have been found.

EVIDENCE SYNTHESIS

The main clinical features of these syndromes are described, especially those concerning the stomatognathic apparatus, referring to the most recent literature. Among these syndromes there are three clinical conditions associated with dental agenesis that are common for the clinician: Down Syndrome, ectodermal dysplasia and labio-palatal cleft.

CONCLUSIONS

It must be kept in mind that the success of the treatment of these patients is based on the compliance of the patient as well as on the collaboration among specialists.