Response to the Letter regarding "The usefulness of the genetic panel in the classification and refinement of diagnostic accuracy of Mexican patients with Marfan syndrome and other connective tissue disorders".

Dear Editor, In relation to the letter expressing concerns about some important points of the article entitled "The usefulness of the genetic panel in the classification and refinement of diagnostic accuracy of Mexican patients with Marfan syndrome and other connective tissue disorders", we would like to comment on the following.  Read more in the PDF.

Letter regarding "The usefulness of the genetic panel in the classification and refinement of diagnostic accuracy of Mexican patients with Marfan syndrome and other connective tissue disorders".

Dear Editor, We have read the article "The usefulness of the genetic panel in the classification and refinement of diagnostic accuracy of Mexican patients with Marfan syndrome and other connective tissue disorders", recently published in your esteemed journal. We are a team dedicated to diagnosing, approaching, and managing patients with connective tissue disorders, particularly hypermobile spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS). We appreciate the research group's effort to address the complexity of connective tissue disorders using a multi-panel genetic approach and their analysis of genotype-phenotype associations in a cohort of Mexican patients. However, we would like to express our concern regarding two specific points that we consider crucial for the comprehensive understanding and management of these disorders. Read more in the PDF.

Unraveling the genetic collagen connection: clinical and therapeutic insights on genetic connective tissue disorders.

Hereditary connective tissue disorders include more than 200 conditions affecting different organs and tissues, compromising the biological role of the extracellular matrix through interference in the synthesis, development, or secretion of collagen and/or its associated proteins. The clinical phenotype includes multiple signs and symptoms, usually nonspecific but of interest to rheumatologists because of musculoskeletal involvement. The patient´s journey to diagnosis is long, and physicians should include these disorders in their differential diagnoses of diseases with systemic involvement. In this review, insights for the diagnosis and treatment of osteogenesis imperfecta, hypermobility spectrum disorder/Ehlers-Danlos syndrome, Marfan, Loeys-Dietz, and Stickler syndromes are presented.

LOXL3 Function Beyond Amino Oxidase and Role in Pathologies, Including Cancer.

Lysyl oxidase like 3 (LOXL3) is a copper-dependent amine oxidase responsible for the crosslinking of collagen and elastin in the extracellular matrix. LOXL3 belongs to a family including other members: LOX, LOXL1, LOXL2, and LOXL4. Autosomal recessive mutations are rare and described in patients with Stickler syndrome, early-onset myopia and non-syndromic cleft palate. Along with an essential function in embryonic development, multiple biological functions have been attributed to LOXL3 in various pathologies related to amino oxidase activity. Additionally, various novel roles have been described for LOXL3, such as the oxidation of fibronectin in myotendinous junction formation, and of deacetylation and deacetylimination activities of STAT3 to control of inflammatory response. In tumors, three distinct roles were described: (1) LOXL3 interacts with SNAIL and contributes to proliferation and metastasis by inducing epithelial-mesenchymal transition in pancreatic ductal adenocarcinoma cells; (2) LOXL3 is localized predominantly in the nucleus associated with invasion and poor gastric cancer prognosis; (3) LOXL3 interacts with proteins involved in DNA stability and mitosis completion, contributing to melanoma progression and sustained proliferation. Here we review the structure, function and activity of LOXL3 in normal and pathological conditions and discuss the potential of LOXL3 as a therapeutic target in various diseases.

[Suspected vascular ehlers danlos syndrome. Case report]. / Sospecha diagnóstica de síndrome de Ehlers Danlos tipo vascular: reporte de un caso y revisión de literatura.

Ehlers Danlos Syndrome comprises a heterogeneous group of genetic disorders of the connective tissue, due to defects in collagen or its modifying enzymes. We report a 21 years old male presenting with translucent skin revealing the subcutaneous venous pattern. He had a thin face, large-appearing eyes, thin lips, thin nose, joint hypermotility and history of hip dysplasia. A vascular Ehlers Danlos Syndrome was suspected. However, the genetic study to confirm the diagnosis was not done.

Sospecha diagnóstica de síndrome de Ehlers Danlos tipo vascular: reporte de un caso y revisión de literatura / Suspected vascular ehlers danlos syndrome: case report

Ehlers Danlos Syndrome comprises a heterogeneous group of genetic disorders of the connective tissue, due to defects in collagen or its modifying enzymes. We report a 21 years old male presenting with translucent skin revealing the subcutaneous venous pattern. He had a thin face, large-appearing eyes, thin lips, thin nose, joint hypermotility and history of hip dysplasia. A vascular Ehlers Danlos Syndrome was suspected. However, the genetic study to confirm the diagnosis was not done.

Periodontitis in marfan syndrome: a case report

A Síndrome de Marfan é uma doença autossômica dominante do tecido conjuntivo, caracterizada por alterações nos sistemas cardiovascular, esquelético e ocular, e que pode aumentar a suscetibilidade à doença periodontal. Esse relato de caso descreve dados periodontais clínicos, microbiológicos e imunológicos de um paciente de 28 anos, gênero masculino, com diagnóstico clínico de Síndrome de Marfan. Neste caso, as principais alterações estão nos sistemas esquelético e ocular. A principal alteração intraoral é a presença de palato profundo e prognatismo mandibular. No exame clínico periodontal, a média do nível clínico de inserção foi de 2,35 mm e índice de sangramento à sondagem de 30%. O tratamento periodontal foi executado em uma sessão de debridamento e orientação de higiene oral, sob antibioticoterapia profilática. Na reavaliação, o paciente apresentou melhora nos parâmetros clínicos periodontais. O relato de caso apresenta um paciente com alterações leves, que afetam a saúde bucal. Em casos de Síndrome de Marfan, a manutenção da saúde periodontal é essencial para um bom prognóstico da saúde bucal.(AU)

Marfan syndrome is an autossomal dominant disorder of connective tissue characterized by alteration in cardiovascular, skeletal and ocular system, and may increase the susceptibility of periodontal disease. This case report describes the clinical, microbiological and immunological periodontal findings in a 28 year old male patient with a clinical diagnosis of Marfan syndrome. The major alterations of the case were in ocular and skeletal system. The major oral alterations were the high arched and narrow palate, and mandibular prognathism. At periodontal examination, an average clinical attachment level loss of 2.35 mm and 30% of bleeding on probing were found. The periodontal treatment was performed, in one session of periodontal debridement with prophylactic antibiotic premedication and oral hygiene instructions. At the revaluation, the patient showed improved clinical parameters. This case report presented a patient with mild features of a genetic disorder which affects oral health. The maintenance of periodontal health in Marfan syndrome cases is essential for a favorable prognosis of oral health.(AU)

Identification of 2 novel ANTXR2 mutations in patients with hyaline fibromatosis syndrome and proposal of a modified grading system.

Juvenile hyaline fibromatosis (JHF) and infantile systemic hyalinosis (ISH) are rare, autosomal recessive disorders of the connective tissue caused by mutations in the gene encoding the anthrax toxin receptor 2 protein (ANTXR2) located on chromosome 4q21. Characteristically, these conditions present with overlapping clinical features, such as nodules and/or pearly papules, gingival hyperplasia, flexion contractures of the joints, and osteolytic bone defects. The present report describes a pair of sibs and three other JHF/ISH patients whose diagnoses were based on typical clinical manifestations and confirmed by histopathologic analyses and/or molecular analysis. A comparison of ISH and JHF, additional thoughts about new terminology (hyaline fibromatosis syndrome) and a modified grading system are also included.

A patient with ascending aortic dilatation, similar to phenotypes of connective tissue disorders.

We report on the clinical and molecular findings of a patient who presented alopecia, epicanthus, micrognathia, retrognathia, high arched palate, hypertelorism, Chiari type I malformation, mixed-type hearing loss but with normal heartbeat Q-T interval, malformed earlobes, down-slanted palpebral fissures, downturned corners of the mouth, syndactyly, atopic eczema, and seizures. The patient was a male adult, 23 years old, with short stature (153 cm) and low weight (50.5 kg), due to severe aortic insufficiency and dilatation of the ascending aorta. Conventional cytogenetic screening did not show any chromosomal gains or losses. Molecular genetic screening was conducted for gene mutations involved in various syndromes; the mutations found included [beta-fibrinogen -455 G>A wt/wt (wt/mut), PAI-1 4G/5G (4G/4G), HPA1 a/b (a/a), MTHFR C677T wt/wt (wt/mut), ACE I/D (I/I), and Apo E E3/E4]. Many clinical and molecular genetics findings overlapped with other conditions associated with arterial tortuosity and arterial aneurysms, including the Marfan, Ehler-Danlos, Shprintzen-Goldberg, and Loeys-Dietz syndromes. Although a diagnosis of Shprintzen-Goldberg syndrome was based on clinical findings and radiographic findings indicate other syndromes, aortic root dilatation seems to be a new symptom, similar to phenotypes of connective tissue disorders. The unique grouping of clinical manifestations in this patient and the molecular genetics findings lead us to suggest that this case could be an example of a previously unrecognized syndrome.

Familial cutaneous collagenoma: a clinicopathologic study of two new cases.

Two siblings with familial cutaneous collagenoma syndrome had the essential clinical features of multiple skin-colored nodules on the trunk and upper arms. On light microscopy, histopathologic findings included excessive accumulation of dense, coarse collagen in the dermis. Elastic tissue stains demonstrated a proportionately diminished number of abnormal elastic fibers intermingled with the collagen bundles. A predominance of densely packed collagen bundles of normal morphology with a marked decrease in abnormal elastic tissue were the major ultrastructural features. The diagnosis was therefore confirmed to be connective tissue nevi of the collagen type. The differential diagnosis of connective tissue nevi disorders is delineated.

Ultrastructural aspects of connective tissue in hereditary gingival fibromatosis.

OBJECTIVE: The purpose of this study was to analyze the ultrastructure of gingival connective tissue from patients in one family affected by hereditary gingival fibromatosis (HGF). STUDY DESIGN: Electron microscopic examination was performed with gingival tissue from 10 patients from a Brazilian family with 132 members. Fifty of 96 persons at risk for this disorder were affected, which is consistent with an autosomal dominant pattern of inheritance. RESULTS: The extracellular matrix showed flocculent material and collagen fibrils with structural abnormalities and variation in diameter. Increased numbers of oxytalan fibers were identified; however, elastic fibers were rare in the analyzed areas. CONCLUSIONS: The structural alterations found in HGF appear similar to those described in certain other heritable collagen disorders, suggesting that HGF should be included in the group of hereditary diseases in which connective tissue alterations have a distinct pattern, in contrast to reactive fibrotic gingival enlargements with no genetic component.

Stickler syndrome without eye involvement is caused by mutations in COL11A2, the gene encoding the alpha2(XI) chain of type XI collagen.

Eye involvement has been considered a principal component feature in Stickler syndrome. However, families lacking eye involvement have been reported. We describe such a family and show that their phenotype is due to a heterozygous 27 basepair deletion in the gene COL11A2, which encodes the alpha2(XI) chain of type XI collagen. This is the second family in whom a COL11A2 mutation has been found to cause Stickler syndrome without eye involvement. This result confirms the role of COL11A2 in the etiopathogenesis of this disorder.

Congenital heart block and subsequent connective tissue disorder in adolescence.

A young girl born to a mother with systemic lupus erythematosus (SLE) had congenital heart block and developed symptoms of a connective tissue disorder at the age of 13 y. When first seen at the age of 15 y she was found to have an unclassified connective tissue disorder and to be seropositive for anti Ro/SSA and U1 RNP. This constellation of clinical/serological features has not been described among the reported handful of patients with congenital heart block and subsequent development of a connective tissue disorder.

[Current concepts on cartilage collagens and their association with disease]. / Conceptos actuales sobre colágenas de cartílago y su asociación con enfermedades.

The main functional role of the collagenous cartilage fibers is to form a stable network to counteract the hydrodynamic pressure generated by the highly hydrodynamic proteoglycan aggregates. The main collagen present in human cartilage is type II, but other proteins such as type IV, VI, IX, X, XI and XIV are also found albeit in small quantities. Several transgenic mice have been developed to study the structural abnormalities as they relate to human disease. Similarly, the study of these structural abnormalities has renewed the interest regarding their pathogenetic role in some hereditary and acquired diseases of cartilage in humans. It is hoped that gene therapy will help correct these abnormalities. We review here these topics.

Novedades moleculares y clínicas de las colágenas / New molecular and clinical aspects of collagens

La colágena es una de las proteínas más abundantes del organismo. Junto con los otros componentes de la matriz extracelular (glucoproteínas no colagenosas, proteoglicanos, lamininas, fibronectinas, tromboespondinas, enectina y tenascina) promueve la adhesión celular, activa vías de señales intracelulares, y regula las actividades de varios factores de crecimiento y de otas proteínas. Durante los últimos 20 años se han identificado por lo menos 19 tipos de colágenas genéticamente diferentes, codificadas por más de 30 genes. En esta primera parte revisamos algunos aspectos novedosos sobre colágenas fibrilares, las formadoras de láminas, las que forman estructuras tipo abalorio, y las multiplexinas. Cuando fue posible correlacionamos las anormalidades de estas proteínas colagenosas con la enfermedad resultante

GAPO syndrome (McKusick 23074)--a connective tissue disorder: report on two affected sibs and on the pathologic findings in the older.

GAPO syndrome was described in 12 patients from 7 families. Constant manifestations include dwarfism, alopecia, pseudoanodontia, and a peculiar, "geriatric" facial appearance. We describe the autopsy findings and all available clinical data on one deceased patient and his living affected sister, previously reported as short abstracts (Epps et al.: Cienc Cult 29(Suppl):740, 1977; Wajntal et al.: Cienc Cult 34(Suppl):705, 1982). Both had the characteristic anomalies of this syndrome but optic atrophy was absent; instead, they had glaucoma and keratoconus; hypogonadism was present in both patients. Biopsy and autopsy findings show that the GAPO syndrome is a dyshistogenetic sequence due to accumulation of extracellular material and thus should be called GAPO dysplasia. We suggest that the basic defect in this autosomal recessive disorder is possibly related to a lack of breakdown of the extracellular components, perhaps due to an enzyme deficiency involved in the metabolism of extracellular matrix.

Stickler's syndrome in the Cleft Palate Clinic.

Stickler's syndrome is a much underdiagnosed entity in the ophthalmic population. It is a dominantly inherited disease of connective tissue whose ocular findings include moderate to severe myopia, vitreoretinal degeneration, retinal detachments, cataracts, and glaucoma. Non-ophthalmologic findings include cleft palate, midfacial hypoplasia, radiographic changes of spondyloepiphyseal dysplasia, narrow pelvis, and broad femoral neck. Twenty percent of patients with Stickler's syndrome will have a cleft palate. We undertook a study to determine the incidence of Stickler's syndrome in patients with an isolated cleft palate, and to see if this screening process would be useful in making an early diagnosis of the syndrome and in genetic counseling. It is important to distinguish this syndrome from that of isolated cleft palate in order to: 1) insure early detection of myopia and monitor for signs of retinal detachment, cataract, and glaucoma; and 2) provide definitive recurrence counseling for families (50% vs 2.3%).

Genetic linkage analysis of hereditary arthro-ophthalmopathy (Stickler syndrome) and the type II procollagen gene.

Hereditary arthro-ophthalmopathy (AO), or Stickler syndrome, is a dominantly inherited disorder characterized by vitreo-retinal degeneration and frequently accompanied by epiphyseal dysplasia and premature degenerative joint disease. Three large families with AO were analyzed for clinical manifestations of the disease and for coinheritance of the genetic defect with RFLPs in the type II procollagen gene (COL2A1). Genetic linkage between AO and COL2A1 was demonstrated in the largest family, with a maximum LOD score of 3.52 at a recombination distance of zero. Data from a second family also supported linkage of AO and COL2A1, with a LOD score of 1.20 at a recombination distance of zero. These results are consistent with the conclusion that mutations in the COL2A1 gene are responsible for AO in these two families. In a third AO family, however, recombination between AO and COL2A1 occurred in at least one meiosis, and the data were inconclusive with respect to linkage.