Type I acquired cutis laxa: Report of a unique progressive case and short review

Cutis laxa is a rare connective tissue disorder, characterized by a reduced number and abnormal properties of elastic fibers throughout the dermis, creating a clinical appearance of premature aging. It can be subdivided into inherited and acquired, the latter rarer than the former, and skin involvement may be localized or generalized. The etiology of acquired cutis laxa (ACL) remains unknown and there is no definitive treatment. We present the case of a 30-year-old man diagnosed with type I ACL with progressive systemic involvement at the renal, pulmonary, and digestive levels. Histological analysis of the skin revealed reduction and fragmentation of elastic fibers. Immunosuppressive treatment was started with prednisone, cyclophosphamide, and rituximab, with which a complete response to proteinuria was achieved and the progression of lung damage was limited. Autoimmune, infectious, and neoplastic diseases were ruled out.

A rare case of secondary cutaneous lymphoplasmacytic lymphoma clinically presenting as acquired cutis laxa

Lymphoplasmacytic lymphoma (LPL) is a rare variant of non-Hodgkin lymphoma, accounting for <1% of cases. Skin involvement in LPL is quite rare-accounting for approximately 5% of extramedullary disease-and includes a variety of clinical morphologies, such as erythematous-to-violaceous plaques, violaceous nodules or tumors, and ulceration at various anatomical sites. Herein, we report the case of a 45-year-old Korean woman who presented with generalized erythematous indurated plaques and pendulous skin growths, which were asymptomatic, with marked diffuse infiltration of lymphocytes and plasma cells in the dermis. Immunohistochemical studies revealed that the lymphoid cells expressed CD3, CD79a, and cytoplasmic IgG, but lacked CD10 and IgM. Moreover, kappa light chain restriction and monoclonal immunoglobulin heavy chain gene rearrangement were observed. Upon further workup, lymphoma involvement was reported in multiple lymph nodes, including those in the cervical and axillary regions. This case shows a unique form of cutaneous LPL clinically presenting as acquired cutis laxa, emphasizing the dermatologists' need to be vigilant for variant forms of this disease.

A novel deletion mutation in the ATP6V0A2 gene in an Iranian patient affected by autosomal recessive cutis laxa

Cutis laxa (CL) can be caused by mutations in a number of genes. Cutis laxa with autosomal recessive inheritance due to mutations in several genes, including mutations in the ATP6V0A2 gene, causes autosomal recessive cutis laxa type 2A (ARCL2A). The ATP6V0A2 gene encodes the a2 subunit in the V-ATPases pump. The V-ATPases are located in the membrane of some organelles, including the Golgi or some vesicles, and act as ATP-dependent proton pumps to pH adjustment intracellular segments. Mutations in the ATP6V0A2 gene consist present in ARCL2A patients. We present the case of a 12-year-old girl who was referred to Rasad Laboratory (Tehran, Iran) at the age of 5 with a set of symptoms of congenital disorders. Her clinical phenotype contains distal symmetrical sensory and motor polyneuropathy, loose joints, large nasal roots, growth delay, and wrinkled skin. Also, there was a history of the parental marriage of consanguinity. A potentially pathogenic homozygous deletion mutation was detected in the ATP6V0A2 gene related to ARCL2A. This mutation has not been reported in the other patients with ARCL2A. A novel homozygous deletion mutation in ATP6V0A2 is supposed to be the reason for disease in our proband.

Progeroid syndrome of De Barsy - a case report and review of ophthalmic literature

BACKGROUND

This report describes a very rare case of progeroid syndrome of De Barsy (Cutis laxa-corneal clouding syndrome).

MATERIALS AND METHODS

A 2 year-old child presented to the pediatric ophthalmology outpatients with bilateral congenital corneal opacification along with dysmorphic facial features, including loose wrinkled skin, progeroid appearance, delayed milestones, short stature, multiple hyper-extensible joints, muscular hypotonia, pectus excavatum and congenital dislocation of the hip joint. The child underwent a detailed ophthalmic work up and systemic evaluation by a clinical geneticist.

RESULTS

Ophthalmic management in the form of bilateral sequential penetrating keratoplasties and a left eye trabeculectomy for medically uncontrolled angle-closure glaucoma was performed. Visual rehabilitation with glasses and amblyopia therapy is ongoing. Histopathology of the corneal button revealed loss of the bowman's layer which was replaced by a fibrous pannus while the stroma showed loss of stromal lamellar architecture with anterior and mid stroma showing vascularization. Genetic testing confirmed a mutation in the PYCR1 gene for a homozygous autosomal recessive cutis laxa type IIB.

CONCLUSIONS

Although rare, De Barsy syndrome is an important cause of corneal opacification at birth with multiple systemic abnormalities that requires intervention.

Functional assessment of homozygous ALDH18A1 variants reveals alterations in amino acid and antioxidant metabolism

Mono- and bi-allelic variants in ALDH18A1 cause a spectrum of human disorders associated with cutaneous and neurological findings that overlap with both cutis laxa and spastic paraplegia. ALDH18A1 encodes the bifunctional enzyme pyrroline-5-carboxylate synthetase (P5CS) that plays a role in the de novo biosynthesis of proline and ornithine. Here we characterize a previously unreported homozygous ALDH18A1 variant (p.Thr331Pro) in four affected probands from two unrelated families, and demonstrate broad-based alterations in amino acid and antioxidant metabolism. These four patients exhibit variable developmental delay, neurological deficits and loose skin. Functional characterization of the p.Thr331Pro variant demonstrated a lack of any impact on the steady-state level of the P5CS monomer or mitochondrial localization of the enzyme, but reduced incorporation of the monomer into P5CS oligomers. Using an unlabeled NMR-based metabolomics approach in patient fibroblasts and ALDH18A1-null human embryonic kidney cells expressing the variant P5CS, we identified reduced abundance of glutamate and several metabolites derived from glutamate, including proline and glutathione. Biosynthesis of the polyamine putrescine, derived from ornithine, was also decreased in patient fibroblasts, highlighting the functional consequence on another metabolic pathway involved in antioxidant responses in the cell. RNA sequencing of patient fibroblasts revealed transcript abundance changes in several metabolic and extracellular matrix-related genes, adding further insight into pathogenic processes associated with impaired P5CS function. Together these findings shed new light on amino acid and antioxidant pathways associated with ALDH18A1-related disorders, and underscore the value of metabolomic and transcriptomic profiling to discover new pathways that impact disease pathogenesis.

Loss of zebrafish atp6v1e1b, encoding a subunit of vacuolar ATPase, recapitulates human ARCL type 2C syndrome and identifies multiple pathobiological signatures

The inability to maintain a strictly regulated endo(lyso)somal acidic pH through the proton-pumping action of the vacuolar-ATPases (v-ATPases) has been associated with various human diseases including heritable connective tissue disorders. Autosomal recessive (AR) cutis laxa (CL) type 2C syndrome is associated with genetic defects in the ATP6V1E1 gene and is characterized by skin wrinkles or loose redundant skin folds with pleiotropic systemic manifestations. The underlying pathological mechanisms leading to the clinical presentations remain largely unknown. Here, we show that loss of atp6v1e1b in zebrafish leads to early mortality, associated with craniofacial dysmorphisms, vascular anomalies, cardiac dysfunction, N-glycosylation defects, hypotonia, and epidermal structural defects. These features are reminiscent of the phenotypic manifestations in ARCL type 2C patients. Our data demonstrates that loss of atp6v1e1b alters endo(lyso)somal protein levels, and interferes with non-canonical v-ATPase pathways in vivo. In order to gain further insights into the processes affected by loss of atp6v1e1b, we performed an untargeted analysis of the transcriptome, metabolome, and lipidome in early atp6v1e1b-deficient larvae. We report multiple affected pathways including but not limited to oxidative phosphorylation, sphingolipid, fatty acid, and energy metabolism together with profound defects on mitochondrial respiration. Taken together, our results identify complex pathobiological effects due to loss of atp6v1e1b in vivo.

Cutis laxa syndromes are pleiotropic disorders of the connective tissue, characterized by skin redundancy and variable systemic manifestations. Cutis laxa syndromes are caused by pathogenic variants in genes encoding structural and regulatory components of the extracellular matrix or in genes encoding components of cellular trafficking, metabolism, and mitochondrial function. Pathogenic variants in genes coding for vacuolar-ATPases, a multisubunit complex responsible for the acidification of multiple intracellular vesicles, cause type 2 cutis laxa syndromes, a group of cutis laxa subtypes further characterized by neurological, skeletal, and rarely cardiopulmonary manifestations. To investigate the pathomechanisms of vacuolar-ATPase dysfunction, we generated zebrafish models that lack a crucial subunit of the vacuolar-ATPases. The mutant zebrafish models show morphological and functional features reminiscent of the phenotypic manifestations in cutis laxa patients carrying pathogenic variants in ATP6V1E1. In-depth analysis at multiple -omic levels identified biological signatures that indicate impairment of signaling pathways, lipid metabolism, and mitochondrial respiration. We anticipate that these data will contribute to a better understanding of the pathogenesis of cutis laxa syndromes and other disorders involving defective v-ATPase function, which may eventually improve patient treatment and management.

Bi-allelic premature truncating variants in LTBP1 cause cutis laxa syndrome

Latent transforming growth factor β (TGFβ)-binding proteins (LTBPs) are microfibril-associated proteins essential for anchoring TGFβ in the extracellular matrix (ECM) as well as for correct assembly of ECM components. Variants in LTBP2, LTBP3, and LTBP4 have been identified in several autosomal recessive Mendelian disorders with skeletal abnormalities with or without impaired development of elastin-rich tissues. Thus far, the human phenotype associated with LTBP1 deficiency has remained enigmatic. In this study, we report homozygous premature truncating LTBP1 variants in eight affected individuals from four unrelated consanguineous families. Affected individuals present with connective tissue features (cutis laxa and inguinal hernia), craniofacial dysmorphology, variable heart defects, and prominent skeletal features (craniosynostosis, short stature, brachydactyly, and syndactyly). In vitro studies on proband-derived dermal fibroblasts indicate distinct molecular mechanisms depending on the position of the variant in LTBP1. C-terminal variants lead to an altered LTBP1 loosely anchored in the microfibrillar network and cause increased ECM deposition in cultured fibroblasts associated with excessive TGFβ growth factor activation and signaling. In contrast, N-terminal truncation results in a loss of LTBP1 that does not alter TGFβ levels or ECM assembly. In vivo validation with two independent zebrafish lines carrying mutations in ltbp1 induce abnormal collagen fibrillogenesis in skin and intervertebral ligaments and ectopic bone formation on the vertebrae. In addition, one of the mutant zebrafish lines shows voluminous and hypo-mineralized vertebrae. Overall, our findings in humans and zebrafish show that LTBP1 function is crucial for skin and bone ECM assembly and homeostasis.

LTBP4 in Health and Disease

Latent transforming growth factor β (TGFβ)-binding protein (LTBP) 4, a member of the LTBP family, shows structural homology with fibrillins. Both these protein types are characterized by calcium-binding epidermal growth factor-like repeats interspersed with 8-cysteine domains. Based on its domain composition and distribution, LTBP4 is thought to adopt an extended structure, facilitating the linear deposition of tropoelastin onto microfibrils. In humans, mutations in LTBP4 result in autosomal recessive cutis laxa type 1C, characterized by redundant skin, pulmonary emphysema, and valvular heart disease. LTBP4 is an essential regulator of TGFβ signaling and is related to development, immunity, injury repair, and diseases, playing a central role in regulating inflammation, fibrosis, and cancer progression. In this review, we focus on medical disorders or diseases that may be manipulated by LTBP4 in order to enhance the understanding of this protein.

Expanding the PURA syndrome phenotype: A child with the recurrent PURA p.(Phe233del) pathogenic variant showing similarities with cutis laxa

BACKGROUND

PURA syndrome is rare autosomal dominant condition characterized by moderate to severe neurodevelopmental delay with absence of speech in nearly all patients and lack of independent ambulation in many. Early-onset problems include excessive hiccups, hypotonia, hypersomnolence, hypothermia, feeding difficulties, recurrent apneas, epileptic seizures, and abnormal nonepileptic movements. Other less common manifestations comprise congenital heart defects, urogenital malformations, and various skeletal, ophthalmological, gastrointestinal, and endocrine anomalies. Up to now, 78 individuals with PURA syndrome and 64 different pathogenic variants have been reported, but no clear-cut genotype-phenotype correlations have emerged so far. Herein, we report the clinical and molecular characterization of a 3-year-old girl with severe hypotonia, global developmental delay, and soft, loose skin, who came to our attention with a suspicion of cutis laxa (CL), which denotes another condition with variable neurodevelopmental problems.

METHODS

Amplicon-based whole exome sequencing was performed, and an in-house pipeline was used to conduct filtering and prioritization of variants. New prediction algorithms for indels were used to validate the pathogenicity of the PURA variant, and results were confirmed with the Sanger method. Finally, we collected clinical and mutational data of all PURA syndrome patients reported yet and compared the clinical features with those of our patient.

RESULTS

Clinical evaluation and biochemical investigations excluded CL and prompted to perform whole exome sequencing, which confirmed the absence of pathogenic variants in all CL-related genes and revealed the known PURA c.697_699del, p.(Phe233del) variant, identified hitherto in seven additional children with PURA syndrome.

CONCLUSIONS

Our data expand the phenotypic spectrum of PURA syndrome by showing that it can be regarded as a differential diagnosis for cutis laxa in early infancy. Our patient and literature review emphasize that a wide clinical variability exists not only between individuals with different PURA variants, but also among patients with the same causal mutation.

Novel defect in phosphatidylinositol 4-kinase type 2-alpha (PI4K2A) at the membrane-enzyme interface is associated with metabolic cutis laxa

Inherited cutis laxa, or inelastic, sagging skin is a genetic condition of premature and generalised connective tissue ageing, affecting various elastic components of the extracellular matrix. Several cutis laxa syndromes are inborn errors of metabolism and lead to severe neurological symptoms. In a patient with cutis laxa, a choreoathetoid movement disorder, dysmorphic features and intellectual disability we performed exome sequencing to elucidate the underlying genetic defect. We identified the amino acid substitution R275W in phosphatidylinositol 4-kinase type IIα, caused by a homozygous missense mutation in the PI4K2A gene. We used lipidomics, complexome profiling and functional studies to measure phosphatidylinositol 4-phosphate synthesis in the patient and evaluated PI4K2A deficient mice to define a novel metabolic disorder. The R275W residue, located on the surface of the protein, is involved in forming electrostatic interactions with the membrane. The catalytic activity of PI4K2A in patient fibroblasts was severely reduced and lipid mass spectrometry showed that particular acyl-chain pools of PI4P and PI(4,5)P₂ were decreased. Phosphoinositide lipids play a major role in intracellular signalling and trafficking and regulate the balance between proliferation and apoptosis. Phosphatidylinositol 4-kinases such as PI4K2A mediate the first step in the main metabolic pathway that generates PI4P, PI(4,5)P₂ and PI(3,4,5)P₃ . Although neurologic involvement is common, cutis laxa has not been reported previously in metabolic defects affecting signalling. Here we describe a patient with a complex neurological phenotype, premature ageing and a mutation in PI4K2A, illustrating the importance of this enzyme in the generation of inositol lipids with particular acylation characteristics.

Skin wrinkling of the upper arms: a case of mid-dermal elastolysis

Mid-dermal elastolysis is a rare acquired elastic tissue disorder with about 100 cases reported in the literature. It is characterized by localized patches of finely wrinkled skin on the shoulder and upper extremities and a band-like loss of elastic tissue in the mid-dermal layer on biopsy. Some patients may have symptoms of discomfort, erythema, and/or pruritis. Mid-dermal elastolysis is predominantly seen in young to middle-aged Caucasian females and extensive skin involvement may lead to cosmetic concerns. Furthermore, it is important to rule out other disorders of elastic fiber that are associated with systemic involvement. We present a case of MDE, discuss the differential diagnosis, and describe characteristic clinical features and histology findings of each condition.

Defining the Clinical, Molecular and Ultrastructural Characteristics in Occipital Horn Syndrome: Two New Cases and Review of the Literature

Occipital horn syndrome (OHS) is a rare connective tissue disorder caused by pathogenic variants in ATP7A, encoding a copper transporter. The main clinical features, including cutis laxa, bony exostoses, and bladder diverticula are attributed to a decreased activity of lysyl oxidase (LOX), a cupro-enzyme involved in collagen crosslinking. The absence of large case series and natural history studies precludes efficient diagnosis and management of OHS patients. This study describes the clinical and molecular characteristics of two new patients and 32 patients previously reported in the literature. We report on the need for long-term specialized care and follow-up, in which MR angiography, echocardiography and spirometry should be incorporated into standard follow-up guidelines for OHS patients, next to neurodevelopmental, orthopedic and urological follow-up. Furthermore, we report on ultrastructural abnormalities including increased collagen diameter, mild elastic fiber abnormalities and multiple autophagolysosomes reflecting the role of lysyl oxidase and defective ATP7A trafficking as pathomechanisms of OHS.

Generalized acquired cutis laxa type 1: a case report and brief review of literature

Cutis laxa, clinically characterized by loose and pendulous skin related to loss of elastic tissue, is a rare heterogeneous condition. It is classified into congenital and acquired types. We report a case of generalized acquired cutis laxa type 1 in a young man following pruritic urticarial plaques. We have done a brief review of literature.

Acquired cutis laxa associated with cutaneous mastocytosis

Cutis laxa is characterized by dramatic wrinkling of skin that is lacking in elasticity due to inherent defects in dermal elastic fibers. Cutis laxa can be caused by genetic and metabolic disorders. It can also be acquired, possibly resulting from inflammatory processes with destruction of elastic fibers. This report describes a 26-year old woman who developed acquired cutis laxa and cutaneous mastocytosis leading to premature aging. She represents a unique co-occurrence of these two separate disease entities. To our knowledge, there has been only one published case report of acquired cutis laxa occurring in association with urticaria pigmentosa in a 4-year old girl. Our case would be a second case that exhibits the coexistence of these two disorders in an adult female.

Clinical presentation of a patient with cutis laxa with systemic involvement: a case report

Cutis laxa (CL) or elastolysis is a rare inherited or acquired connective tissue disorder in which the skin becomes inelastic and hangs loosely in folds (Mitra et al., 2013). The clinical presentation and the type of inheritance show considerable heterogeneity (Shehzad et al., 2010). We aimed to present the atypical case of a young male patient diagnosed at 36-year-old with CL with systemic involvement. The complex medical history, with a suspected but unconfirmed progeria at nine months, repeated lung and urinary infections, complicated inguinoscrotal hernia, prostatic hypertrophy, bilateral entropion, colorectal diverticula and heart failure, suggested a systemic genetic disease, but the absence of family history made the diagnosis of CL difficult. The skin biopsy and the characteristic features discovered during anatomopathological exam made possible the positive and differential diagnosis, creating the link between the various organ involvement and CL diagnosis. Because of the age of our patient, of normal growth and mental development, and negative family history, we suspected an autosomal dominant form of CL with early onset and severe manifestation. Of course, we cannot exclude a recessive form, due to the heterogeneity of this disease.

Primary Anetoderma: A Case Report and Its Modified Classification

A fifty-nine-year-old healthy male presented with fifteen round pouches around his bilateral shoulders and proximal thighs, at which elasticity was lost on palpation. Histopathological examinations demonstrated that the lesional dermis was thinner than normal skin and there was loss of elastic fibers and mild inflammatory cell infiltration. Because there was no preceding inflammatory skin lesion or associated diseases, the patient was diagnosed with primary anetoderma. This is a rare case of primary anetoderma that showed loss of elastic fibers and the thinner dermis. In addition, a modified classification is proposed considering associated diseases with a review of literature.

Clinical and biochemical features guiding the diagnostics in neurometabolic cutis laxa

Patients with cutis laxa (CL) have wrinkled, sagging skin with decreased elasticity. Skin symptoms are associated with variable systemic involvement. The most common, genetically highly heterogeneous form of autosomal recessive CL, ARCL2, is frequently associated with variable metabolic and neurological symptoms. Progeroid symptoms, dysmorphic features, hypotonia and psychomotor retardation are highly overlapping in the early phase of these disorders. This makes the genetic diagnosis often challenging. In search for discriminatory symptoms, we prospectively evaluated clinical, neurologic, metabolic and genetic features in our patient cohort referred for suspected ARCL. From a cohort of 26 children, we confirmed mutations in genes associated with ARCL in 16 children (14 probands), including 12 novel mutations. Abnormal glycosylation and gyration abnormalities were mostly, but not always associated with ATP6V0A2 mutations. Epilepsy was most common in ATP6V0A2 defects. Corpus callosum dysgenesis was associated with PYCR1 and ALDH18A1 mutations. Dystonic posturing was discriminatory for PYCR1 and ALDH18A1 defects. Metabolic markers of mitochondrial dysfunction were found in one patient with PYCR1 mutations. So far unreported white matter abnormalities were found associated with GORAB and RIN2 mutations. We describe a large cohort of CL patients with neurologic involvement. Migration defects and corpus callosum hypoplasia were not always diagnostic for a specific genetic defect in CL. All patients with ATP6V0A2 defects had abnormal glycosylation. To conclude, central nervous system and metabolic abnormalities were discriminatory in this genetically heterogeneous group, although not always diagnostic for a certain genetic defect in CL.

Cutis laxa type II with mutation in the pyrroline-5-carboxylate reductase 1 gene

A 14-year-old Iranian boy with congenital cutis laxa and several other typical autosomal recessive type II features was examined. Mutation analysis of the pyrroline-5-carboxylate reductase 1 gene revealed a single-base deletion (c.345delC) in exon 4 leading to frame shift and premature termination of translation.

Acquired cutis laxa in a 55-year-old female with multiple myeloma and serologic evidence of systemic lupus erythematosus

Cutis laxa (CL) is a rare connective tissue disorder characterized by loosely hanging skin folds. Histopathology reveals degenerative changes in the dermal elastic fibers, although loss of elastin can also occur in alveolar walls, blood vessels, and other organs. The coexistence of autoimmune diseases and monoclonal gammopathies is rare but well documented in the literature. Here we report an unusual case of cutis laxa (CL) preceding the development of serologic evidence of systemic lupus erythematosus (SLE) and a diagnosis of multiple myeloma (MM) by seven and eleven years respectively.

A novel mutation in PYCR1 causes an autosomal recessive cutis laxa with premature aging features in a family

The autosomal recessive form of type II cutis laxa (ARCL II) is characterized by the appearance of redundant, inelastic skin with wrinkling, an aged look and additional variable systemic involvement including intrauterine growth retardation, failure to thrive, developmental delay, dysmorphism, osseous abnormality, and CNS manifestations. Several genetic defects have been found in patients and families with the clinical manifestations of ARCL II. Recently, mutations in PYCR1 have been linked to cutis laxa with progeroid features. We ascertained two siblings with of ARCL II born to non-consanguineous parents. Mutation analysis of PYCR1 revealed a novel single-base deletion (c.345delC) in exon 4 leading to frame-shift and premature stop of translation. The effect of this mutation results in a strong reduction of PYCR1 expression in skin fibroblasts from affected siblings. These two cases extend the genotypic spectrum of PYCR1-related ARCL II.

Ultrastructural demonstration of a relationship between acquired cutis laxa and monoclonal gammopathy

Acquired cutis laxa is an uncommon disorder sometimes associated with monoclonal gammopathy and multiple myeloma, although the mechanism of this link is unclear. We report here a case of a 34-year-old man with generalized acquired cutis laxa and monoclonal light chain disease with renal and neurological involvement. Electron microscopy examination of a skin sample revealed shortened and fragmented elastic fibres in the reticular dermis and normal collagen bundles. Immunogold labelling revealed anti-lambda antibodies closely bound to the microfibrillar component of elastic fibres, thus supporting a causal relationship between monoclonal gammopathy and the changes in skin elasticity.

Mechanisms of emphysema in autosomal dominant cutis laxa

Heterozygous elastin gene mutations cause autosomal dominant cutis laxa associated with emphysema and aortic aneurysms. To investigate the molecular mechanisms leading to cutis laxa in vivo, we generated transgenic mice by pronuclear injection of minigenes encoding normal human tropoelastin (WT) or tropoelastin with a cutis laxa mutation (CL). Three independent founder lines of CL mice showed emphysematous pulmonary airspace enlargement. No consistent dermatological or cardiovascular pathologies were observed. One CL and one WT line were selected for detailed studies. Both mutant and control transgenic animals showed elastin deposition into pulmonary elastic fibers, indicated by increased desmosine levels in the lung and by colocalization of transgenic and endogenous elastin by immunostaining. CL mice showed increased static lung compliance and decreased stiffness of lung tissue. In addition, markers of transforming growth factor-β (TGFβ) signaling and the unfolded protein response (UPR) were elevated together with increased apoptosis in the lungs of CL animals. We conclude that the synthesis of mutant elastin in CL activates multiple downstream disease pathways by triggering a UPR, altered mechanical signaling, increased release of TGFβ and apoptosis. We propose that the combined effects of these processes lead to the development of an emphysematous pulmonary phenotype in CL.

Cutis laxa: a case report and an update

Very few cases of Cutis Laxa are reported worldwide. This is the first case report of its kind from Bangladesh. A 10 year-old girl looking very aged was admitted in the paediatric ward of Dhaka Medical College with most striking skin feature. There was loosely hanging skin over the face which was inelastic, hyper extensible and which recoils slowly after stretching. She had downward slanting palpebral fissures, periorbital oedema, a broad flat nose with everted nostril, sagging cheeks, and large and soft ears. Skin biopsy showed fragmentation of the elastic tissue with collagen tissue in the dermis, which was suggestive of Cutis Laxa. Her chest x-ray showed hypertranslucent lung fields, prominence of pulmonary conus area and some ring like opacity near the lower zone with cardiomegaly, which is suggestive of corpulmonale with bronchiectasis. Her echocardiography showed dilated right atrium, ventricle and pulmonary artery which were suggestive of corpulmonale. All these confirmed the diagnosis.

Mutation in pyrroline-5-carboxylate reductase 1 gene in families with cutis laxa type 2

Autosomal-recessive cutis laxa type 2 (ARCL2) is a multisystem disorder characterized by the appearance of premature aging, wrinkled and lax skin, joint laxity, and a general developmental delay. Cutis laxa includes a family of clinically overlapping conditions with confusing nomenclature, generally requiring molecular analyses for definitive diagnosis. Six genes are currently known to mutate to yield one of these related conditions. We ascertained a cohort of typical ARCL2 patients from a subpopulation isolate within eastern Canada. Homozygosity mapping with high-density SNP genotyping excluded all six known genes, and instead identified a single homozygous region near the telomere of chromosome 17, shared identically by state by all genotyped affected individuals from the families. A putative pathogenic variant was identified by direct DNA sequencing of genes within the region. The single nucleotide change leads to a missense mutation adjacent to a splice junction in the gene encoding pyrroline-5-carboxylate reductase 1 (PYCR1). Bioinformatic analysis predicted a pathogenic effect of the variant on splice donor site function. Skipping of the associated exon was confirmed in RNA from blood lymphocytes of affected homozygotes and heterozygous mutation carriers. Exon skipping leads to deletion of the reductase functional domain-coding region and an obligatory downstream frameshift. PYCR1 plays a critical role in proline biosynthesis. Pathogenicity of the genetic variant in PYCR1 is likely, given that a similar clinical phenotype has been documented for mutation carriers of another proline biosynthetic enzyme, pyrroline-5-carboxylate synthase. Our results support a significant role for proline in normal development.

Acquired cutis laxa following urticarial vasculitis associated with IgA myeloma

Cutis laxa (CL) is an inherited or acquired connective tissue disorder characterized clinically by loosely hanging skin folds. There is often preceding cutaneous inflammatory eruption (ie, urticaria, eczema, erythema multiforme), and there is frequently internal organ involvement of the gastrointestinal, urogenital, pulmonary, and cardiovascular systems. Histologically, there are degenerative changes in the dermal elastic fibers. Of the few reports on this rare disorder, authors have speculated about an immune-mediated destruction of elastic fibers, and monoclonal gammopathies, such as multiple myeloma or heavy chain deposition disease, have a recognized association with CL. We report an unusual case of rapidly progressing acquired CL associated with leukocytoclastic vasculitis, IgA myeloma, and an immune complex-mediated glomerulonephritis. Light microscopy of the lax skin revealed complete absence of elastic fibers in areas of vasculitis.

Functional rescue of elastin insufficiency in mice by the human elastin gene: implications for mouse models of human disease

Diseases linked to the elastin gene arise from loss-of-function mutations leading to protein insufficiency (supravalvular aortic stenosis) or from missense mutations that alter the properties of the elastin protein (dominant cutis laxa). Modeling these diseases in mice is problematic because of structural differences between the human and mouse genes. To address this problem, we developed a humanized elastin mouse with elastin production being controlled by the human elastin gene in a bacterial artificial chromosome. The temporal and spatial expression pattern of the human transgene mirrors the endogenous murine gene, and the human gene accurately recapitulates the alternative-splicing pattern found in humans. Human elastin protein interacts with mouse elastin to form functional elastic fibers and when expressed in the elastin haploinsufficient background reverses the hypertension and cardiovascular changes associated with that phenotype. Elastin from the human transgene also rescues the perinatal lethality associated with the null phenotype. The results of this study confirm that reestablishing normal elastin levels is a logical objective for treating diseases of elastin insufficiency such as supravalvular aortic stenosis. This study also illustrates how differences in gene structure and alternative splicing present unique problems for modeling human diseases in mice.

Cutis laxa acquise généralisée associée à un myélome : découverte de grandes cellules vacuolisées dermiques

INTRODUCTION

Cutis laxa is a rare disorder characterized by loss of elastic tissue. Several organs are often involved such as the skin, lungs, heart, digestive system or genitourinary tract. It may be inherited or acquired, generalized or localized. Its pathogenesis is unclear. Association of acquired cutis laxa with myeloma or plasma cell dyscrasia is very rare. We report a case of acquired cutis laxa associated with a myeloma.

CASE REPORT

A 59 year-old woman was admitted for skin hyperlaxity present for a number of years. Light microscopic examination of a skin sample revealed fragmented elastic fibers. Electron microscopic examination of the elastic network demonstrated numerous large vacuolated cells with the appearance of macrophages around abnormal elastic and collagen fibers of the reticular dermis. In addition, a stage-1 IgG lambda myeloma was detected. The patient was treated by thalidomide for one year. After this treatment, electron microscopy examination did not reveal any large vacuolated cells in the dermis, and elastic and collagen fibers were not modified and skin laxity seemed to be stabilized.

DISCUSSION

Acquired cutis laxa may be associated with many systemic diseases or can appear after inflammatory skin diseases. Seven cases of generalized cutis laxa associated with myeloma and four cases associated with plasma cell dyscrasia have been reported in the literature. In our case, as in 2 previously described cases, large vacuolated cells resembling macrophages were seen in the dermis. They were thought to play a role in cutis laxa.

Association of cutis laxa and genital prolapse: a case report

Cutis laxa (CL) is an extremely inherited or acquired connective tissue disorder characterised by a markedly reduced systemic elastin content. Genital abnormalities in patients with CL have been rarely reported. We report such a case in a 48-year-old CL patient affected by genital prolapse, focusing on immunohistological and molecular biology assessment of elastin and collagen type I, III, VI content in the main uterine ligaments. The woman was referred to our department for the onset of a rapidly progressing genital prolapse and urinary incontinence. The patient underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy and sacrocolpopexy. Punch biopsies from both cardinal and uterosacral ligaments revealed a dramatic reduction in elastin and an increase in collagen type VI content. The present report seems to underline the central role exerted primarily by elastin in the supportive connective tissue and might contribute to the knowledge of extracellular matrix abnormalities at the basis of genital abnormalities in CL patients.

Nonsurgical tightening of skin laxity: a new radiofrequency approach

BACKGROUND

Improvement in skin laxity can be difficult to achieve without invasive surgical procedures. Monopolar radiofrequency (RF) treatment is used by physicians to heat skin and promote tissue tightening and contouring. RF technology produces an electric current that generates heat through resistance in the dermis and subcutaneous tissue. The thermal effect depends on the conductivity features of the treated tissue. When heated, collagen fibrils will denature and contract, which is believed to lead to the observed tissue tightening.

METHODS

Ninety-three consecutive patients with mild to moderate laxity were included in the study. The Surgitron Dual Frequency RF (Radiowave technology, Ellman International) was used to treat skin laxity. The application of RF energy took place in an ambulatory setting with no need for skin sterilization or anesthesia.

RESULTS

Patients immediately noticed a microlifting retraction in the treated tissues according to the vectors mapped in the area. There were no significant complications and the majority of patients were satisfied with the procedure and able to return to their daily routine after leaving the office, thereby substantiating the popularity of noninvasive rejuvenating procedures.

Fibulin-5 mutations: mechanisms of impaired elastic fiber formation in recessive cutis laxa

To elucidate the molecular mechanisms of impaired elastic fiber formation in recessive cutis laxa, we have investigated two disease-causing missense substitutions in fibulin-5, C217R and S227P. Pulse-chase immunoprecipitation experiments indicated that S227P mutant fibulin-5 was synthesized and secreted by skin fibroblasts at a reduced rate when compared with the wild-type protein. Both mutants failed to be incorporated into elastic fibers by transfected rat lung fibroblasts. Purified recombinant fibulin-5 with either mutation showed reduced affinity for tropoelastin in solid-phase binding assays. Furthermore, S227P mutant fibulin-5 also showed impaired association with fibrillin-1 microfibrils. The same mutation triggered an endoplasmic reticulum (ER) stress response, as indicated by the strong co-localization of this mutant protein with folding chaperones in the ER, including calreticulin, immunoglobulin-binding protein and protein disulfide isomerase, and by increased rates of apoptosis in patient fibroblasts. Histological analysis of skin sections from a cutis laxa patient with a homozygous S227P mutation showed a lack of fibulin-5 in the extracellular matrix and a concomitant disorganization of dermal elastic fibers. By electron microscopy, elastic fibers in the skin of this patient showed a failure of elastin globules to fuse into a continuous elastic fiber core. We conclude that recessive cutis laxa mutations in fibulin-5 result in misfolding, decreased secretion and a reduced interaction with elastin and fibrillin-1 leading to impaired elastic fiber development. These findings support the hypothesis that fibulin-5 is necessary for elastic fiber formation by facilitating the deposition of elastin onto a microfibrillar scaffold via direct molecular interactions.

Geroderma osteodysplastica. Report of a new family

We report a family in which geroderma osteodysplastica affected two male siblings. They showed the characteristic features associated with this syndrome: a prematurely aged face with wrinkly, lax skin, more prominent on the acral regions, associated with joint laxity, osteoporosis, and skeletal abnormalities. The main histologic abnormalities were fragmented elastic fibers that were diminished in number. Although collagen fibers showed changes in their orientation, they were normal in structure and number. We consider the differential diagnosis with other syndromes associated with cutis laxa using clinical, radiologic, and histopathologic criteria.

Fibulin-4: a novel gene for an autosomal recessive cutis laxa syndrome

Cutis laxa is a condition characterized by redundant, pendulous, and inelastic skin. We identified a patient with recessive inheritance of a missense mutation (169G-->A; E57K) in the Fibulin-4 gene. She had multiple bone fractures at birth and was diagnosed with cutis laxa, vascular tortuosity, ascending aortic aneurysm, developmental emphysema, inguinal and diaphragmatic hernia, joint laxity, and pectus excavatum by age 2 years. Her skin showed markedly underdeveloped elastic fibers, and the extracellular matrix laid down by her skin fibroblasts contained dramatically reduced amounts of fibulin-4. We conclude that fibulin-4 is necessary for elastic fiber formation and connective tissue development.

Cutis laxa type II and wrinkly skin syndrome: distinct phenotypes

Cutis laxa is a heterogeneous group of disorders with variable phenotypes and inheritance patterns. Type II cutis laxa has features overlapping with wrinkly skin syndrome, as a result of which they are regarded as one disorder with a variable spectrum of severity by some authors. To overcome this existing confusion, we present three patients with cutis laxa type II and review the literature to highlight the important differentiating features between cutis laxa type II and wrinkly skin syndrome.

Inflammatory destruction of elastic fibers in acquired cutis laxa is associated with missense alleles in the elastin and fibulin-5 genes

Cutis laxa (CL) is a condition characterized by redundant, pendulous, and inelastic skin. Acquired CL has been reported in patients with inflammatory diseases. The goal of this study was to investigate whether genetic lesions predispose patients to the development of acquired CL. We report a patient who developed CL following a Toxocara canis parasitism. He later had an aortic root aneurysm that required surgical correction. Histological evaluation showed inflammation followed by destruction of elastic fibers in both the skin and the aorta. Mutational analysis showed that the patient was heterozygous for an inherited fibulin-5 (FBLN5) allele G202R and compound heterozygous for elastin (ELN) alleles A55V and G773D. Western blotting indicated abnormal proteolytic processing of tropoelastin (TE) in patient fibroblasts. The FBLN5 202R allele on the other hand led to increased interaction of FBLN5 and TE and increased deposition of insoluble ELN partially rescuing the deficiency conferred by ELN mutation G773D. We demonstrated that the interaction of ELN and FBLN5 alleles results in elastic fibers susceptible to inflammatory destruction. These results suggest that the pathogenesis of acquired CL involves an underlying genetic susceptibility and highlight the importance of molecular genetic analysis in patients with idiopathic connective tissue disorders.

[Localized acquired cutis laxa associated with trachyonychia]

Acquired cutis laxa is a rare disease of unknown cause, which affects elastin metabolism. Clinically, it is characterized by redundant skin and hyperelasticity, while the histological study shows a reduction in or absence of elastic fibers in the dermis. We present a case of localized acquired cutis laxa associated with trachyonychia.