Rubinstein-Taybi syndrome and spontaneous keloids

Dermatological findings in Rubinstein-Taybi Syndrome

Rubinstein-Taybi Syndrome is a rare congenital multisystem syndrome inherited in an autosomal dominant pattern caused by mutations in CREBBP and EP300 genes in approximately 60% and 10% respectively. These genes encode two highly evolutionarily conserved, ubiquitously expressed, and homologous lysine-acetyltransferases, that are involved in number of basic cellular activities, such as DNA repair, cell proliferation, growth, differentiation, apoptosis of cells, and tumor suppression. It is mainly characterized by global developmental delay, moderate to severe intellectual disability, postnatal retardation, microcephaly, skeletal anomalies including broad/short, angled thumbs and/or large first toes, short stature, and dysmorphic facial features. There is an increased risk to develop tumors mainly meningiomas and pilomatrixomas, without a clear genotype-phenotype correlation. Although not considered as characteristic manifestations, numerous cutaneous anomalies have also been reported in patients with this entity. Both susceptibility to the formation of keloids and pilomatricomas are the most often associated cutaneous features. In this review, we discuss the genetics, diagnosis, and clinical features in Rubinstein-Taybi Syndrome with a review of the major dermatological manifestations.

Extracorporeal shockwave therapy for treatment of keloid scars

The purpose of this investigation was to study the effectiveness of extracorporeal shockwave therapy (ESWT) for the treatment of keloid scars, and compared the results with intralesional steroid injection. Thirty-nine patients were randomly divided into 22 in ESWT group and 17 in steroid group. The ESWT group received 3 ESWT treatments in 6 weeks. The steroid group received three intra-lesional triamcinolone injections in 6 weeks. The evaluations included gross morphology, functional outcome, local blood flow perfusion, biopsy for histopathological examination, and immunohistochemical analysis. Both groups showed significant improvements in appearance with less discoloration, flattening and softer consistency, and more elasticity of the lesions. There is a significant reduction in keloid height after treatment in both groups, and significant differences are noticed between two groups after treatment. The volume of keloid was decreased after treatment but there is no statistically significant difference between two groups. Both groups showed comparable functional scores, POSAS patient, and observer scales. The blood flow perfusion rates were statistically not significant between two groups before and after treatments. Histopathological findings revealed no significant difference in cell count, cell activity, and cell concentration between two groups. After ESWT, the significant decreases in collagen type I, type III, and Masson Trichrome stain were observed as compared with steroid group. However, very little changes were noticed in angiogenesis, inflammatory cytokines, proliferating and regeneration, and apoptosis, with no statistical significance noticed between two groups before and after treatment. This study revealed that ESWT showed comparable functional outcome and POSAS patient and observer scales as compared with steroid injection for keloid scars. Treatment of keloid scars with ESWT resulted in significant decreases in collagen fibers and increases in MMP-13 enzyme.

Keloids in Rubinstein-Taybi syndrome: a clinical study

BACKGROUND

Rubinstein-Taybi syndrome (RSTS) is a multiple congenital anomalies-intellectual disability syndrome. One of the complications is keloid formation. Keloids are proliferative fibrous growths resulting from excessive tissue response to skin trauma.

OBJECTIVES

To describe the clinical characteristics of keloids in individuals with RSTS reported in the literature and in a cohort of personally evaluated individuals with RSTS.

PATIENTS AND METHODS

We performed a literature search for descriptions of RSTS individuals with keloids. All known individuals with RSTS in the Netherlands filled out three dedicated questionnaires. All individuals with (possible) keloids were personally evaluated. A further series of individuals with RSTS from the U.K. was personally evaluated.

RESULTS

Reliable data were available for 62 of the 83 Dutch individuals with RSTS and showed 15 individuals with RSTS (24%) to have keloids. The 15 Dutch and 12 U.K. individuals with RSTS with keloids demonstrated that most patients have multiple keloids (n > 1: 82%; n > 5: 30%). Mean age of onset is 11·9 years. The majority of keloids are located on the shoulders and chest. The mean length × width of the largest keloid was 7·1 × 2·8 cm, and the mean thickness was 0·7 cm. All affected individuals complained of itching. Generally, treatment results were disappointing.

CONCLUSIONS

Keloids occur in 24% of individuals with RSTS, either spontaneously or after a minor trauma, usually starting in early puberty. Management schedules have disappointing results. RSTS is a Mendelian disorder with a known molecular basis, and offers excellent opportunities to study the pathogenesis of keloids in general and to search for possible treatments.

Novel cAMP binding protein-BP (CREBBP) mutation in a girl with Rubinstein-Taybi syndrome, GH deficiency, Arnold Chiari malformation and pituitary hypoplasia

Background

Rubinstein-Taybi syndrome (RTS) is a rare autosomal dominant disorder (prevalence 1:125,000) characterised by broad thumbs and halluces, facial dysmorphism, psychomotor development delay, skeletal defects, abnormalities in the posterior fossa and short stature. The known genetic causes are point mutations or deletions of the cAMP-response element binding protein-BP (CREBBP) (50-60% of the cases) and of the homologous gene E1A-binding protein (EP300) (5%).

Case presentation

We describe, for the first time in literature, a RTS Caucasian girl, 14-year-old, with growth hormone (GH) deficiency, pituitary hypoplasia, Arnold Chiari malformation type 1, double syringomyelic cavity and a novel CREBBP mutation (c.3546insCC).

Conclusion

We hypothesize that CREBBP mutation we have identified in this patient could be responsible also for RTS atypical features as GH deficiency and pituitary hypoplasia.

Beyond the Borders of Keloid Formation: A Case Report

The keloid scar is a cutaneous mass characterized by nodular fibroblastic proliferation of dermis and a predilection for distinctive anatomical locations. However, keloid extension to neighbouring tissue as a nonsyndromic entity has not been described. In the present report, a case involving a 48-year-old woman with extensive bilateral keloids of the ear lobules and neck following ear piercing is presented.

Long-term results following osteotomy of the thumb delta phalanx in Rubinstein-Taybi Syndrome

Rubinstein-Taybi Syndrome is a rare condition affecting 1:125,000 children. It is associated with short broad radially deviated thumbs, secondary to a delta proximal phalanx of the thumb. We undertook a retrospective review of seven children (13 thumbs) with Rubinstein-Taybi syndrome whose thumbs were treated using a corrective osteotomy to the delta phalanx over a 13 year period. The types of osteotomy used in the series were reverse wedge osteotomy, opening wedge osteotomy and dome shaped osteotomy. The mean preoperative radial deviation of thumbs was 68 degrees (range 45-85 degrees ). At follow up five of the 13 thumbs demonstrated some residual radial deviation. All recurrences occurred in the dome shaped osteotomy group. Our data suggest that surgery is effective in correcting the deformity, but there is a risk of incomplete correction or recurrence. Despite the recurrence the mean postoperative deformity was significantly better than preoperatively and the majority of patients families subjectively reported good function. No patient in our series has yet undergone further corrective surgery.

Genetics of keloid scarring

Keloid scarring, also known as keloid disease (KD), is a common, abnormally raised fibroproliferative cutaneous lesion that can occur following even minor skin trauma. The aetiopathogenesis of KD has remained an enigma todate compounded by an ill-defined clinical management. There is strong evidence suggesting a genetic susceptibility in individuals affected by KD, including familial heritability, common occurrence in twins and high prevalence in certain ethnic populations. This review aims to address the genetic aspects of KD that have been described in present literature that include inheritance patterns, linkage studies, case-control association studies, whole genome gene expression microarray studies and gene pathways that were significant in KD. In addition to our clinical and scientific background in KD, we used search engines, Scopus, Scirus and PubMed, which searched for key terms covering various genetic aspects of KD. Additionally, genes reported in seven whole genome gene expression microarray studies were separately compared in detail. Our findings indicate a varied inheritance pattern in KD (predominantly autosomal dominant), linkage loci (chromosomes 2q23 and 7p11), several human leukocyte antigen (HLA) alleles (HLA-DRB1*15, HLA-DQA1*0104, DQ-B1*0501 and DQB1*0503), negative candidate gene case-control association studies and at least 25 dysregulated genes reported in multiple microarray studies. The major pathways reportedly proposed to be involved in KD include apoptosis, mitogen-activated protein kinase, transforming growth factor-beta, interleukin-6 and plasminogen activator inhibitor-1. In summary, involvement of more than one gene is likely to be responsible for susceptibility to KD. A better understanding of the genes involved in KD may potentially lead to the development of more effective diagnostic, therapeutic and prognostic measures.

Two adults with Rubinstein-Taybi syndrome with mild mental retardation, glaucoma, normal growth and skull circumference, and camptodactyly of third fingers

The Rubinstein-Taybi syndrome (RTS; OMIM 180849) is a well-defined mental retardation/multiple congenital anomalies (MR/MCA) syndrome characterized by postnatal growth retardation, microcephaly, specific facial features, broad thumbs and halluces, and MR of variable degree. Ten percent of patients with RTS have a microdeletion 16p13.3, 40-50% carry a mutation of the CREBBP gene and another 3% have a mutation in the EP300 gene. In the remaining patients with clinically suspected RTS no mutation can be detected. Here we describe two patients with an RTS phenotype, one with a mutation in the CREBBP gene and the other without a detectable CREBBP or EP300 mutation and without a chromosomal imbalance on high-resolution arrays. Both patients present with the characteristic facial RTS phenotype, broad thumbs and big toes, mild MR, formation of keloids and glaucoma, but without postnatal growth retardation or microcephaly. In addition, they have both congenital camptodactyly of third (and fourth) fingers, which has not reported in RTS previously. We suggest that they represent a clinical subtype of RTS.

Molecular dissection of abnormal wound healing processes resulting in keloid disease

Keloids are locally aggressive scars that typically invade into healthy surrounding skin and cause both physical and psychosocial distress to the patient. These pathological scars occur following minimal skin trauma after a variety of causes including burns and trauma. Although the pathogenesis of keloid disease is not well understood, it is considered to be the end product of an abnormal healing process. The aim of this review was to investigate the molecular and cellular pathobiology of keloid disease in relation to the normal wound healing process. The molecular aberrances in keloids that correlate with the molecular mechanisms in normal wound healing can be categorized into three groups: (1) extracellular matrix proteins and their degradation, (2) cytokines and growth factors, and (3) apoptotic pathways. With respect to cellular involvements, fibroblasts are the most well-studied cell population. However, it is unclear whether the fibroblast is the causative cell; they are modulated by other cell populations in wound repair, such as keratinocytes and macrophages. This review presents a detailed account of individual phases of the healing process and how they may potentially be implicated in aberrant raised scar formation, which may help in clarifying the mechanisms involved in keloid disease pathogenesis.

Genetic susceptibility to raised dermal scarring

Raised skin scars, such as keloid and hypertrophic scars mostly occur post-wounding in the human dermis. There is compelling evidence for a genetic component to these conditions, given the familial predisposition, varied incidence in different ethnic populations and the presence in twins. The aim of this study was to perform a systematic review of the literature regarding genetic susceptibility to raised dermal scarring. We identified relevant articles by a systematic search of relevant search engines. Key search terms included: keloid disease, hypertrophic scarring, fibrosis, linkage analysis, gene expression, human leucocyte antigen system (HLA), twins, families, case-control association study and congenital syndromes. Numerous candidate genes have been identified, along with potential linkage regions on different chromosomes. Recent data also suggest that carriers of specific major histocompatibility complex (MHC) alleles, in particular HLA-DRB1*15, HLA-DQA1*0104, DQB1*0501 and DQB1*0503, are at increased risk of developing keloid scarring. In addition, distinct immunophenotypical profiles can distinguish between keloid and hypertrophic scars. Keloid and hypertrophic scars are multifaceted aberrations of the healing process with as yet incompletely understood aetiologies. Current data suggest a genetic susceptibility with a strong immunogenic component to dermal fibrosis with MHC genes being implicated. It appears unlikely that a single gene is responsible for the development of raised dermal scars. A likely scenario may involve the interaction of several gene pathways in addition to environmental factors. The ability to assess accurately an individual's potential genetic susceptibility to raised scarring may lead to a more personalized approach to their management in the future.

Rubinstein-Taybi syndrome: clinical and molecular overview

Rubinstein-Taybi syndrome is characterised by mental retardation, growth retardation and a particular dysmorphology. The syndrome is rare, with a frequency of approximately one affected individual in 100,000 newborns. Mutations in two genes - CREBBP and EP300 - have been identified to cause the syndrome. These two genes show strong homology and encode histone acetyltransferases (HATs), which are transcriptional co-activators involved in many signalling pathways. Loss of HAT activity is sufficient to account for the phenomena seen in Rubinstein-Taybi patients. Although some mutations found in CREBBP are translocations, inversions and large deletions, most are point mutations or small deletions and insertions. Mutations in EP300 are comparatively rare. Extensive screening of patients has revealed mutations in CREBBP and EP300 in around 50% of cases. The cause of the syndrome in the remaining patients remains to be identified, but other genes could also be involved. Here, we describe the clinical presentation of Rubinstein-Taybi syndrome, review the mutation spectrum and discuss the current understanding of causative molecular mechanisms.

Rubinstein-Taybi syndrome

In this review a short overview of pertinent clinical and molecular data of the Rubinstein-Taybi syndrome are provided. A diagnostic decision algorithm, and major issues that should be considered in the management of patients are discussed. Suggestions for further research are given.

Keloids and neoplasms in the Rubinstein-Taybi syndrome

In a series of 574 individuals with the Rubinstein-Taybi syndrome, 28 had keloids, and 19 had one or more neoplasms. The array of malignant neoplasms does not suggest an etiology or pathogenesis in common. One possible exception is that four cases of leukemia were observed. When the data for malignant and benign neoplasms were combined, at least nine of the 22 could have arisen from developmental errors. The apparent excess of keloid formation indicates overreaction to mild injury, with no known relevance to neoplasia but of potential interest in future studies of scar formation.

Rubinstein-Taybi syndrome: a natural history study

In order to examine several aspects related to the natural history of the Rubinstein-Taybi syndrome, we performed a questionnaire study of 50 patients who had been diagnosed with the condition. The cases were ascertained through a national parent support group and all of the individuals had been reared at home. The most frequent problems encountered were inadequate weight gain in infancy, eye problems, dental abnormalities, congenital heart defects, urinary tract problems, and severe constipation. These medical disorders and others resulted in approximately 10 times the average number of hospitalizations and surgeries as the general population of children. None of the 91 sibs of our study group were affected with the condition. Thirty-seven patients had undergone psychological testing with an average IQ of 51 and a range of 30 to 79. Timing for the attainment of various developmental stages was also determined. Individuals with Rubinstein-Taybi syndrome were found to have particular difficulty with expressive speech skills. Indexes for maladaptive behavior were calculated showing that approximately 10% of patients had significant behavior problems.

Etiology and recurrence risk in Rubinstein-Taybi syndrome

Epidemiologic data on 45 patients with Rubinstein-Taybi syndrome from the Netherlands and 50 patients from the USA are compared with data from 407 patients reported in the literature. The 502 probands had a total of 708 sibs, including one probable recurrence. In 12 of 13 proven or possible monozygotic twins both children were affected. Two patients have reproduced with one affected and 2 normal offspring. The empiric recurrence risk figure for sibs is 0.1%. The recurrence risk for offspring of affected individuals could be as high as 50%. The cause of the syndrome remains unknown. There were no clues for autosomal recessive or X-linked inheritance, nor for a teratogenic cause. No consistent chromosome anomaly was found. An autosomal dominant mutation, either as submicroscopic chromosome deletion or duplication, or a point mutation seems the most likely explanation.

Broad thumb-hallux (Rubinstein-Taybi) syndrome 1957-1988

This presentation records the early history of the description of the broad thumb-hallux syndrome and attempts to update the current state of knowledge about this syndrome. Information was collected and reviewed on 571 individuals from the world literature, from communications with colleagues and families of affected individuals, and from personal observation. The diagnosis was established in most cases by confirming the concurrence of the constellation of major diagnostic criteria, including broad short terminal phalanges of the thumbs and halluces, with or without angulation deformity; characteristic facial appearance with beaked or straight nose, antimongoloid slant of palpebral fissures, apparent or clinical hypertelorism and grimacing smile; stature and head circumference (OFC) below 50th centile; mental, motor, social, and language retardation; stiff awkward gait; and incomplete or delayed descent of testes in males. Information on associated clinical factors, familial occurrence, and cytogenetic findings is presented.

Keloids - clinical diagnosis, pathogenesis, and treatment options. Keloide - klinische Diagnose, Pathogenese und Behandlungsoptionen

Keloids are defined as excessive scar tissue formation extending beyond the area of the original skin injury and occurring in predisposed individuals. They are considered to be a result of abnormal wound healing. The pathogenetic mechanisms that cause keloids remain unknown. Experiments with cells derived from keloid tissue revealed a number of abnormalities in cellular functions, such as in proliferation, apoptosis, or expression of growth factors and extracellular matrix proteins. Furthermore, several studies have reported altered keratinocyte-fibroblast interactions in keloids. Despite the diverse pathological changes in cellular functions and expression profiles of cells derived from keloid tissue, recent genetic studies have provided evidence that single genes may act as major regulators of keloid formation. We provide an overview of the pathogenetic mechanisms of keloid formation in the context of their clinical characteristics and current therapeutic approaches.

Keloid-like scleroderma

A 62-year-old female who developed concomitantly acrosclerosis and keloid-like lesions is described. Biopsy specimens from these linear lesions showed a fibrous proliferation in the dermis composed mostly of normal-appearing, horizontally oriented collagen bundles and myofibroblasts, thus resembling a scar. Keloidal scleroderma is a rare variant of scleroderma. The diagnosis is considered for patients with scleroderma who develop lesions clinically and histologically indistinguishable from keloids. This case demonstrates for the first time that the histopathologic findings can mimic those of a scar, rather than a keloid, and hence is appropriately designated as keloid-like scleroderma. Clinical pathological correlation is mandatory for the correct diagnosis.

The bilobed flap: a new application in the reconstruction of congenital thumb deviation

Congenital radial angulation deformity of the thumb in Rubinstein-Taybi syndrome is generally corrected by a wedge osteotomy of the delta phalanx and a redistribution of the overlying skin using a Z-plasty or, rarely, skin grafting. We describe a new application of the bilobed flap in the reconstruction of the thumb and discuss its advantages over traditional methods in providing tension-free skin cover, excellent access to the delta phalanx and aesthetically acceptable scars.

Rubinstein--Taybi syndrome and ulerythema ophryogenes in a 9-year-old boy

Rubinstein-Taybi syndrome is characterized by the presence of a peculiar facies, mental retardation, and broad thumbs and great toes. Several associated cutaneous abnormalities have been reported with this syndrome. Ulerythema ophryogenes is a form of follicular keratosis associated occasionally with other ectodermal defects and congenital anomalies. We describe a 9-year-old child with Rubinstein-Taybi syndrome and ulerythema ophryogenes. This association has not been described previously to our knowledge.

Multiple pilomatricomas in Rubinstein-Taybi syndrome: a case report

Rubinstein-Taybi syndrome is a multisystem developmental disorder due to an autosomal dominant mutation. It is clinically defined by the presence of peculiar facies, mental retardation, and broad thumbs and first toes. Important dermatologic findings include hirsutism, keloids, hemangiomas, and dermatoglyphic abnormalities. We report a 12-year-old girl with the typical phenotype of Rubinstein-Taybi syndrome, associated with numerous pilomatricomas. These are benign epithelial neoplasms with hair cell differentiation that may have a familial transmission. Pilomatricomas have not been reported in patients with Rubinstein-Taybi syndrome, although their association with myotonic dystrophy, another autosomal dominant disorder, is well known. Possibilities to explain the association include contiguous gene syndrome, the action of a pleiotropic gene, predisposition to malformations, and mere coincidence.