Ehlers-Danlos Syndrome, Periodontal Type, 1

A number sign (#) is used with this entry because of evidence that Ehlers-Danlos syndrome periodontal type 1 (EDSPD1) is caused by heterozygous mutation in the C1R gene (613785) on chromosome 12p13.

Description

Ehlers-Danlos syndrome (EDS) is a clinically and genetically heterogeneous group of connective tissue disorders defined by joint laxity and skin alterations that include hyperextensibility, atrophic scarring, and bruising. Periodontal EDS (EDSPD; previously designated 'EDS VIII') is a specific subtype of EDS with autosomal dominant inheritance, in which the defining feature is an EDS phenotype combined with severe periodontal inflammation. In childhood, periodontal inflammation in EDSPD is characterized by extensive gingivitis in response to mild plaque accumulation. In the teens, early-onset periodontitis leads to inflammatory destruction of dental attachment and premature loss of teeth. Other clinical features include pretibial hyperpigmentation, acrogeria, skin and gum fragility, scarring, generalized and/or distal joint hypermobility, and bruising out of proportion to trauma. There are also reports of life-threatening complications such as arterial or gastrointestinal ruptures (summary by Kapferer-Seebacher et al., 2016).

Genetic Heterogeneity of Ehlers-Danlos Syndrome, Periodontal Type

Ehlers-Danlos syndrome periodontal type 2 (EDSPD2; 617174) is caused by mutation in the C1S gene (120580) on chromosome 12p13.

Reviews

Kapferer-Seebacher et al. (2016) tabulated the clinical features of 93 EDSPD patients with mutations in the C1R or C1S genes (77 and 16 patients, respectively) and observed that the most prevalent features included early-onset periodontitis, gingival recessions, and thin gingiva and/or absence of attached gingiva. Easy bruising was present in most patients, as were pretibial hyperpigmentation, skin fragility, and mildly elastic skin. About half of patients exhibited atrophic scars or wide scarring and/or prominent vasculature. Joint hypermobility was not a consistent finding, and if present was mild and often limited to small joints. Other variable features included recurrent infections, joint pain, flat feet, marfanoid facial features, scoliosis, osteoarthritis, and hernias. A minority of patients had joint dislocations; aneurysms occurred in 4 families, and autoimmune disorders occurred in 1 family. Cancer appeared to be more prevalent in patients with C1S mutations.

Nomenclature

Beighton et al. (1998) reported on a revised nosology of the Ehlers-Danlos syndromes, designated the Villefranche classification. Major and minor diagnostic criteria were defined for each type and complemented whenever possible with laboratory findings. Six main descriptive types were substituted for earlier types numbered with Roman numerals: classic type (EDS I and II), hypermobility type (EDS III), vascular type (EDS IV), kyphoscoliosis type (EDS VI), arthrochalasia type (EDS VIIA and VIIB), and dermatosparaxis type (EDS VIIC). Six other forms were listed, one of which was the periodontitis type (EDS VIII).

Clinical Features

McKusick (1972) reported a family in which affected members exhibited skin lesions resembling necrobiosis lipoidica diabeticorum in association with periodontal disease leading to early loss of teeth. The skin lesions consisted of symmetrical patches on the front of the shins, about 5 inches long, covered by parchment skin and discolored by blood pigments. The appearance resembled that in the Ehlers-Danlos syndrome. The knees showed small 'cigarette-paper scars.' Loose-jointedness and general bruisability and cutaneous fragility were not present. Furthermore, although the histology of the lesions of the skin suggested necrobiosis lipoidica diabeticorum, no evidence of diabetes was uncovered in any member of the family. In addition to the proband, her father, several paternal uncles and aunts, and a cousin were affected.

Stewart et al. (1977) described a case of this syndrome. The father and a half brother were also affected. A grandparent may have been affected. The proband had some marfanoid manifestations: arachnodactyly, tall stature, and 'skinniness.' Fragile skin, loose joints and cigarette-paper scars were present. Dental problems included extensive periodontal destruction, i.e., alveolar bone loss around the teeth resulting in premature loss of teeth, as well as propensity for calculus formation.

Linch and Acton (1979) reported on a 10-year-old black girl with this disorder in whom alveolar bone loss had led initially to the diagnosis of juvenile destructive periodontitis. Nelson and King (1981) reported the disorder in 5 persons in 3 generations. In this family, a 19-year-old woman had periodontal disease beginning at age 13 years. Her sister, aged 18 years, had other features of EDS but did not have periodontitis. Their grandmother had progressive periodontitis with loosening and subsequent loss of permanent teeth, becoming edentulous by age 20 years.

In their patient with EDS type VIII and severe periodontitis at age 12 years, Lapiere and Nusgens (1981) found a possible defect in type III collagen, which they suggested showed impaired secretion. Tsipouras et al. (1986) described a family with EDS type IV (130050) with a defect in secretion of type III collagen; the proposita showed alveolar bone loss at age 21 years. Byers et al. (1983) suggested that periodontal disease may be a characteristic of EDS type IV also and that only biochemical studies can distinguish types IV and VIII. Biesecker et al. (1991) described a family in which a father and son had EDS type VIII. Some of the clinical features impressed them as suggesting premature aging. Indeed, the father had been thought to have Werner syndrome (277700). He had become edentulous at age 16 years because of severe periodontal disease. Multiple striae on the abdominal wall were described in the father and striae on the thighs in the 17-year-old son. The son's teeth were loose and the gingivae erythematous.

Hoffman et al. (1991) described a patient with EDS type VIII in whom immunity to type I collagen appeared to be responsible for unusual features: intractable vasculitis and resorptive osteolysis. The female patient had a dislocated right hip at birth. By age 10 years, her permanent teeth underwent premature loosening, requiring dental plates. Within several months of the onset of menses at age 13 years, she developed generalized persistent urticaria, which on biopsy was shown to represent small-vessel vasculitis. Within 6 months, symmetric polyarthralgia occurred, affecting small and large joints. The cutaneous manifestations progressed; indeed, they never completely resolved. Erosive arthritis and osteolysis occurred in the hands, toes, and temporomandibular joints. Loss of skin elasticity created prominent furrows, wrinkling, and laxity. Over the next 10 years she developed progressive aortic and mitral regurgitation and possible mitral stenosis. No evidence of connective tissue disorder was found in the family except that the patient's mother had undergone mitral valve replacement for rheumatic heart disease. Collagen analyses identified morphologic and physical abnormalities of type I collagen. The patient's T lymphocytes could be propagated in vitro with type I collagen and produced a 60-kD lymphokine that bound this protein. Dyne et al. (1993) classified Ehlers-Danlos syndrome in a 9-year-old girl as type VIII because of the presence of periodontitis and a family history of premature loss of permanent teeth. No alterations in the synthesis or secretion of types I and II collagen or in the serum levels of type III procollagen amino-terminal propeptide were found, and morphologic studies revealed only nonspecific changes. In an erratum, Dyne et al. (1993) pointed out that the summary should have read as follows: 'No alterations in the synthesis or secretion of types I and III collagen...'

Rahman et al. (2003) reported a large Swedish pedigree in which 17 individuals over 5 generations had EDS VIII. The predominant dental features of the affected individuals were premature periodontal inflammation and gingival recession, usually detectable in childhood, with rapid progression throughout adolescence and early adulthood. Complete loss of adult dentition typically occurred by the end of the third decade in individuals born before 1950. Dental x-rays of selected family members showed progressive loss of periodontal supporting tissue and loss of bony tissue. Affected individuals showed typical features of EDS, with generalized joint laxity, thin atrophic skin (especially over the dorsum of the hands and feet), and circumscribed hemosiderotic pretibial plaques, which could be either thickened or atrophic. Affected individuals were tall, with arm spans greater than their heights.

Reinstein et al. (2011) studied a 4-generation kindred with EDS VIII in which 12 affected individuals had joint hypermobility, normal scar formation but eventual scar atrophy, and severe periodontal disease with dental caries and infections. Age at onset and severity of symptoms were variable among affected individuals, confirming intrafamilial variability in this subtype of EDS. Four more family members demonstrated clinical findings suggestive of a connective tissue disorder, such as umbilical hernia, soft skin texture, and various degrees of joint hypermobility; a clear status could not be assigned due to their young age and paucity of other symptoms, primarily dental.

Reinstein et al. (2012) described a woman, her mother, and her maternal grandmother who were affected with EDS VIII. All 3 became edentulous, at ages 20, 35, and 37 years, respectively, and all had chronic pain involving the back, knees, hips, and finger joints. In addition, the proband and her mother had osteoporosis by bone density scan; the authors noted that they also exhibited the long nose with narrow root and prominent tip that had previously been observed in patients with EDS and periodontal involvement. Considerable childhood joint hypermobility was reported by the patients, but progressive stiffness made it less noticeable at the time of examination. The proband also reported easy bruising but normal wound healing and normal scar formation. Radiologic evaluation of the proband at age 37 showed moderate scoliosis, ossicular findings at the right hip suggestive of gluteal muscle tendinopathy, changes at the right shoulder also suggesting ligamentous disease, and marked osteoarthritis of the right knee. Reinstein et al. (2012) concluded that EDS VIII can be associated with early-onset degenerative joint disease and reduced bone density.

Reinstein et al. (2013) reported a 4-generation family with EDS VIII. The proband was a 7-year-old girl who had gingival disease first noted at age 3 years, as well as easy shin bruising and occasional nosebleeds. Examination at age 5 showed minimal bruising on the shins, mild joint hypermobility, and normal skin consistency with normal scarring. Dental examination revealed severe generalized gingival edema and erythema associated with abundant bacterial biofilm accumulation, and gingival recession was present on some primary and permanent teeth. The gingival tissues were of poor quality with minimally attached and keratinized gingivae, and visible capillaries confirmed its thin nature. Her father had discolored pretibial scarring from shin bruising in adolescence and a history of receding gums and periodontal disease with loss of 6 permanent teeth by age 39. He had no history of dislocations or other joint symptoms, and examination revealed no joint hypermobility, with normal skin and scarring. Electron microscopy of pretibial skin showed decreased collagen content, abnormal variation in collagen fibril diameter, and some abnormally shaped fibers suggesting collagen misassembly. The proband's deceased paternal grandfather was similarly affected and had full dentures by age 42 years; he had severe shin bruising but no joint pain, laxity, or dislocations. The proband's 86-year-old great-grandfather began losing teeth in his early teens; he never had shin bruising or joint problems, and had normal scarring. Reinstein et al. (2013) concluded that EDS VIII is clinically variable and that even cases lacking the associated skin and joint manifestations may show microscopic evidence of collagen disorganization. They reviewed previous reports and suggested that the diagnosis should be considered in patients with dominant familial forms of early-onset periodontal disease and dental loss even when there is little other clinical basis for considering a connective tissue disorder.

Cikla et al. (2014) described a 42-year-old woman with a diagnosis of EDS VIII who died after surgery for an aneurysm of the middle cerebral artery. She was initially evaluated at age 13 years because of frequent bruising and fragility of the anterior tibial skin as well as gingival retraction and alveolar absorption. She had lost all teeth spontaneously or from extraction by age 19 years due to periodontitis. Examination at age 30 showed soft but not hyperextensible skin, dramatic pigmentary scarring over the tibiae, and mild joint hyperextensibility. Because of phenotypic overlap with EDS IV (130050), biochemical and genetic analysis of skin fibroblast collagens was performed, which demonstrated normal type III collagen (COL3A1; 120180) sequence and expression. At age 42 years, she presented with subarachnoid hemorrhage due to a blood blister-like aneurysm of the left middle cerebral artery. A coiling procedure was unsuccessful and she had continued bleeding from the aneurysm; her neurologic condition remained poor after a second surgical procedure and care was withdrawn at the family's request. Cikla et al. (2014) concluded that patients with EDS VIII may be at risk for catastrophic vascular events.

George et al. (2016) reported 2 unrelated patients with EDS VIII who also exhibited laryngeal pathology resulting in chronic hoarseness. The first was a 24-year-old Bangladeshi man with early-onset periodontitis in whom examination revealed widespread cutaneous atrophy and hemosiderosis of the shins and ankles, an easily visible venous pattern over the upper arms, thighs, and chest, and acrogeric changes of the face, hands, and feet. His hoarseness resulted from bilateral vocal cord sulci due to laryngeal mucosal hypertrophy. The second patient was a 33-year-old white woman with early-onset periodontal disease who also displayed an acrogeric facial appearance and had a hoarse voice due to cricoarytenoid fibrosis. Her father had early-onset periodontal disease, and she had 2-year-old twin boys with similar acrogeric facial features and lax skin, suggesting that they were likely to be affected. In both probands, collagen I and III protein analyses were normal, and COL3A1 sequencing was normal.

Mapping

Rahman et al. (2003) performed a genomewide search in 72 individuals from 5 generations of a large Swedish pedigree with EDS VIII and established linkage to a 7-cM interval on chromosome 12p13, generating a maximum multipoint lod score of 5.17. Analysis of 4 other pedigrees with this disorder showed 2 consistent with linkage to 12p13 and 2 in which linkage could be excluded, indicating that EDS type VIII is a genetically heterogeneous disorder. Rahman et al. (2003) noted that chromosome 12p13 had not previously been implicated in either EDS or periodontal disease and was not known to contain any collagen genes or collagen-processing enzymes. Mutation screening of the microfibril-associated glycoprotein-2 gene (601103), within the minimum interval, did not reveal any likely pathogenic mutations.

Teare and Barrett (2005) used EDS VIII as an example to illustrate parametric linkage analysis of pedigrees.

Heterogeneity

Reinstein et al. (2011) studied a 4-generation kindred with EDS VIII and stated that initial linkage analysis indicated that this pedigree was not linked to the previously reported region on chromosome 12p13, thus confirming genetic locus heterogeneity in EDS type VIII.

Molecular Genetics

Kapferer-Seebacher et al. (2016) studied 19 unrelated families with the periodontal type of EDS, including the families previously reported by Stewart et al. (1977), Hartsfield and Kousseff (1990), Rahman et al. (2003), Reinstein et al. (2011, 2012, 2013), Cikla et al. (2014), and George et al. (2016). Exome sequencing followed by targeted sequencing identified heterozygous variants in the C1R gene on chromosome 12p13 in affected individuals from 15 of the families (see, e.g., 613785.0001-613785.0007), and 2 of the families had mutations in the adjacent C1S gene (120580.0003 and 120580.0004; see EDSPD2, 617174). The mutations segregated with disease in the families and were found in the ExAC, 1000 Genomes Project, ClinVar, or dbSNP (March 2016) databases. No pathogenic mutations in C1R or C1S were identified in 71 patients with aggressive periodontitis but no EDS-like features, or in 11 patients clinically diagnosed with vascular EDS. In addition, there were 2 mutation-negative EDSPD families (Reinstein et al. (2011, 2012)); Kapferer-Seebacher et al. (2016) noted that the affected individuals in those families exhibited periodontitis and EDS-type connective tissue features, but did not have pretibial hyperpigmentation.