Syndromes with gingival fibromatosis: A systematic review

Enamel renal syndrome: A case report with calcifications in pulp, gingivae, dental follicle and kidneys

BACKGROUND

Enamel renal syndrome is a rare genetic disorder transmitted through an autosomal recessive mode. It is featured by a hypoplastic amelogenesis imperfecta, delayed tooth eruption, gingival fibromatosis, and nephrocalcinosis. The aim of this study was to describe clinically, radiologically, and histologically the main features of enamel renal syndrome and to point out the role of dentists in early diagnosing this genetic disease.

MATERIALS AND METHODS

Our case of enamel renal syndrome was initially described by clinical, radiographic, and genealogic data, then complemented by ultrasound examination of the kidneys and microscopic observation of gingivae.

RESULTS

The study showed the presence of amelogenesis imperfecta (AI), several teeth impaction, gingival hyperplasia, bilateral nephrocalcinosis, and multiple calcifications in pulp, gingiva, dental follicle, and kidneys.

CONCLUSION

The patient was followed for a full mouth rehabilitation and also referred to a nephrology for global medical checkup. The dentist plays a key role in diagnosing genetic diseases and in referring patients for medical comprehensive care.

New evidence of genetic heterogeneity causing hereditary gingival fibromatosis and ALK and CD36 as new candidate genes

BACKGROUND

Hereditary gingival fibromatosis (HGF) is an uncommon genetic condition characterized by slow but progressive fibrous, non-hemorrhagic, and painless growth of the gingival tissues due to the increased deposition of collagen and other macromolecules of the extracellular matrix. HGF occurs in approximately 1:750,000 individuals and can exhibit dominant or recessive inheritance. To date, five loci (2p21-p22, 2p22.3-p23.3, 4q12, 5q13-q22, and 11p15) and three genes [REST (RE1-silencing transcription factor), SOS1 (Son-of-Sevenless-1), and ZNF862 (zinc finger protein 862 gene)] have been associated with HGF. Here, our study aimed to identify genetic variants associated with HGF by applying whole-exome sequencing (WES) and bioinformatics analyses.

METHODS

Thirteen Brazilian individuals with HGF and nine relatives without HGF from four unrelated families were chosen for our investigation. Blood collected from the patients and their relatives were used for WES. Five Web-available tools, namely, CADD, PolyPhen, SIFT, Mutation Taster, and Franklin's algorithms, were used to predict protein damage.

RESULTS

WES revealed pathogenic variants affecting the known HGF genes REST (c.1491_1492delAG) and SOS1 (c.3265_3266insTAAC) in two families. Additionally, potentially pathogenic variants segregating in the other two families were mapped to ALK receptor tyrosine kinase gene (ALK) (c.361C > T) and to collagen type I receptor and thrombospondin receptor gene (CD36) (c.1133G > T).

CONCLUSION

Our findings reinforce the high genetic heterogeneity of HGF, identifying new variants in HGF known genes (REST and SOS1) and ALK and CD36 as new genes that cause HGF.

Non-Plaque Induced Diffuse Gingival Overgrowth: An Overview

Non-plaque induced diffuse gingival overgrowth represents a broad class of conditions caused by several etiological factors. The aim of this review is to highlight the most recent updates and classifications of all the existent gingival overgrowths. In addition, we highlighted the diagnostic pathway that should be employed in patients affected by gingival overgrowth. Gingival overgrowth can be related to syndromic diseases including a wide spectrum of genetic and chromosomal alterations. However, thanks to scientific sharing and the availability of genetic panels it is possible to obtain an accurate phenotypic identification of well-known syndromes and also to identify new ones. This narrative review shows that through rigid, strict diagnostic protocols, the work of the clinician is greatly facilitated, despite the wide variety of pathologies considered. In conclusion, the exchange of specialists’ competencies and the multidisciplinary management of these patients, are crucial to reach diagnosis and the correct clinical-therapeutic management.

Hereditary Gingival Fibromatosis and Developmental Anomalies: A Case Report

Hereditary gingival fibromatosis is the most common genetic form of gingival fibromatosis that develops as a slow, progressive, benign, localized, or generalized enlargement of the keratinized gingiva. It is a genetically heterogeneous disorder transmitted as an autosomal dominant or autosomal recessive trait or appears sporadically. Here, we report a case of a male patient with generalized gingival hyperplasia with great tissue extension to the palatal region, bilateral mandibular torus, bilateral exostosis in the maxillary posterior region, anterior open bite, and diastema in anterior maxilla and mandible teeth. The mucous membranes were healthy and normal colored, with pale pink gums and firm teeth upon palpation. Computed tomography also revealed images suggestive of supernumerary teeth. The patient reported that his mother and a maternal aunt have the same gingival condition. Considering the gingival characteristic, the patient's family history, and the absence of other possible etiological factors of gingival hyperplasia, the diagnostic hypothesis was hereditary gingival fibromatosis. The surgical removal of the enlarged tissue through gingivectomy with internal bevel, osteoplasty, and removal of supernumerary teeth with a subsequent filling of the surgical sites with platelet and leukocyte-rich fibrin membranes in the same surgical time presented good functional and aesthetic results for the young patient with hereditary gingival fibromatosis. It is a viable possibility for clinical management of similar cases.

Juvenile hyaline fibromatosis: A clinicopathological study of five cases

Juvenile hyaline fibromatosis (JHF) is an extremely rare autosomal recessive disease that typically presents in infancy or early childhood. Largely due to the rarity, JHF is still not widely recognized by clinicians and pathologists in China. It is not uncommonly to misdiagnose the disease as other types of disorders. In this study, we present our experience with five cases of JHF to enhance the recognition of this rare but distinctive entity. There were 4 males and 1 female, with age at presentation ranging from 5 to 44 years. All patients presented with multiple subcutaneous nodular lesions of varying size in various parts of the body since birth or early childhood. Three patients also had joint involvement. Pathologically, the lesions were poorly circumscribed, located mainly in the dermis and subcutis. All five cases were characterized by abundant homogeneous hyaline-like matrix that differs sharply from the adjacent connective tissue, which stained strongly with periodic acid-Schiff (PAS) and was diastase resistant. Embedded within the eosinophilic glassy matrix were cords or small clusters of plump spindled to epithelioid cells, frequently with clear cytoplasm. Familiarity with the characteristic features of JHF is not only important in avoiding misdiagnosis but also essential for clinical management and prognostic evaluation.

Pathogenesis of Enamel-Renal Syndrome Associated Gingival Fibromatosis: A Proteomic Approach

The enamel renal syndrome (ERS) is a rare disorder featured by amelogenesis imperfecta, gingival fibromatosis and nephrocalcinosis. ERS is caused by bi-allelic mutations in the secretory pathway pseudokinase FAM20A. How mutations in FAM20A may modify the gingival connective tissue homeostasis and cause fibromatosis is currently unknown. We here analyzed conditioned media of gingival fibroblasts (GFs) obtained from four unrelated ERS patients carrying distinct mutations and control subjects. Secretomic analysis identified 109 dysregulated proteins whose abundance had increased (69 proteins) or decreased (40 proteins) at least 1.5-fold compared to control GFs. Proteins over-represented were mainly involved in extracellular matrix organization, collagen fibril assembly, and biomineralization whereas those under-represented were extracellular matrix-associated proteins. More specifically, transforming growth factor-beta 2, a member of the TGFβ family involved in both mineralization and fibrosis was strongly increased in samples from GFs of ERS patients and so were various known targets of the TGFβ signaling pathway including Collagens, Matrix metallopeptidase 2 and Fibronectin. For the over-expressed proteins quantitative RT-PCR analysis showed increased transcript levels, suggesting increased synthesis and this was further confirmed at the tissue level. Additional immunohistochemical and western blot analyses showed activation and nuclear localization of the classical TGFβ effector phospho-Smad3 in both ERS gingival tissue and ERS GFs. Exposure of the mutant cells to TGFB1 further upregulated the expression of TGFβ targets suggesting that this pathway could be a central player in the pathogenesis of the ERS gingival fibromatosis. In conclusion our data strongly suggest that TGFβ -induced modifications of the extracellular matrix contribute to the pathogenesis of ERS. To our knowledge this is the first proteomic-based analysis of FAM20A-associated modifications.