RESUMEN
Autosomal recessive congenital ichthyosis (ARCI) is a rare and heterogeneous skin cornification disorder presenting with generalized scaling and varying degrees of erythema. Clinical manifestations range from lamellar ichthyosis (LI), congenital ichthyosiform erythroderma (CIE) through the most severe form of ARCI, Harlequin ichthyosis (HI). We used homozygosity mapping, whole-exome and direct sequencing to delineate the relative distribution of pathogenic variants as well as identify genotype-phenotype correlations in a cohort of 62 Middle Eastern families with ARCI of various ethnic backgrounds. Pathogenic variants were identified in most ARCI-associated genes including TGM1 (21%), CYP4F22 (18%), ALOX12B (14%), ABCA12 (10%), ALOXE3 (6%), NIPAL4 (5%), PNPLA1 (3%), LIPN (2%) and SDR9C7 (2%). In 19% of cases, no mutation was identified. Our cohort revealed a higher prevalence of CYP4F22 and ABCA12 pathogenic variants and a lower prevalence of TGM1 and NIPAL4 variants, as compared to data obtained in other regions of the world. Most variants (89%) in ALOX12B were associated with CIE and were the most common cause of ARCI among patients of Muslim origin (26%). Palmoplantar keratoderma associated with fissures was exclusively a result of pathogenic variants in TGM1. To our knowledge, this is the largest cohort study of ARCI in the Middle-Eastern population reported to date. Our data demonstrate the importance of population-tailored mutation screening strategies and shed light upon specific genotype-phenotype correlations.
Asunto(s)
Eritrodermia Ictiosiforme Congénita/epidemiología , Eritrodermia Ictiosiforme Congénita/genética , Estudios de Cohortes , Genotipo , Humanos , Medio Oriente/epidemiología , Epidemiología Molecular , Mutación , FenotipoRESUMEN
Leukoencephalopathies are a group of white matter disorders related to abnormal formation, maintenance, and turnover of myelin in the central nervous system. These disorders of the brain are categorized according to neuroradiological and pathophysiological criteria. Herein, we have identified a unique form of leukoencephalopathy in seven patients presenting at ages 2 to 4 months with progressive microcephaly, spastic quadriparesis, and global developmental delay. Clinical, metabolic, and imaging characterization of seven patients followed by homozygosity mapping and linkage analysis were performed. Next generation sequencing, bioinformatics, and segregation analyses followed, to determine a loss of function sequence variation in the phospholipase A2-activating protein encoding gene (PLAA). Expression and functional studies of the encoded protein were performed and included measurement of prostaglandin E2 and cytosolic phospholipase A2 activity in membrane fractions of fibroblasts derived from patients and healthy controls. Plaa-null mice were generated and prostaglandin E2 levels were measured in different tissues. The novel phenotype of our patients segregated with a homozygous loss-of-function sequence variant, causing the substitution of leucine at position 752 to phenylalanine, in PLAA, which causes disruption of the protein's ability to induce prostaglandin E2 and cytosolic phospholipase A2 synthesis in patients' fibroblasts. Plaa-null mice were perinatal lethal with reduced brain levels of prostaglandin E2 The non-functional phospholipase A2-activating protein and the associated neurological phenotype, reported herein for the first time, join other complex phospholipid defects that cause leukoencephalopathies in humans, emphasizing the importance of this axis in white matter development and maintenance.
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Leucoencefalopatías/genética , Leucoencefalopatías/metabolismo , Leucoencefalopatías/fisiopatología , Proteínas/genética , Proteínas/metabolismo , Adolescente , Animales , Encéfalo/embriología , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Encéfalo/patología , Niño , Consanguinidad , Dinoprostona/metabolismo , Embrión de Mamíferos , Salud de la Familia , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/ultraestructura , Regulación de la Expresión Génica/genética , Humanos , Leucoencefalopatías/diagnóstico por imagen , Pulmón/patología , Masculino , Ratones , Ratones Transgénicos , Modelos Moleculares , FN-kappa B/metabolismo , Fosfolipasas A2/metabolismo , Piel/patologíaRESUMEN
INTRODUCTION: Although dermatologic conditions bring relatively few people to the Emergency Department, hospitalized patients, especially older people, often suffer from skin problems that contribute to their morbidity. AIMS: We wanted to identify the frequency, clinical course, treatment and influence on hospitalization of dermatologic conditions in patients hospitalized in internal and geriatric departments in Galilee Medical Center. We concentrated on two groups of adults, aged 40-65 years (adult group) and above 65 years (elderly group), in order to understand differences in the cause of referral, type of diagnosis and mode of treatment. METHODS: We performed a retrospective review of 82 hospitalized patients who were referred for dermatological consultation between May-September 2013. Of the 82 patients, 47.6% made up the 'adult' group and 52.4% the 'elderly' group; 62.2% of patients were independent, 18.3% partially independent and 19.5% needed nursing care. RESULTS: Skin infections (38.3%), allergy (mostly drug induced) (23.5%) and trophic disorders (18.5%) were the most common diagnoses. 'Elderly' were less often referred to dermatological consultation than 'adults' (44.3% vs. 55.7%, respectively); skin infections were more common in the 'elderly' (44.8% vs. 55.7%). Nursing care patients (19.5%) were least referred to dermatological consultation, but severity of skin condition (the number of diagnoses and number of treatments per patient) was greater in nursing care patients. CONCLUSIONS: The clinical course between the independent and nursing care patients varies in the number of requests, the different type of diagnoses, the severity of the conditions and the number of treatments provided. DISCUSSION: Our study emphasizes the importance of skin examination by a dermatologist, considering the high number of referrals for dermatological consultations. On the other hand, there was a significant difference between the 'elderly' and 'adult' groups, with fewer referrals for dermatological consultations by the medical staff in the 'elderly' group. Our results resemble those in the literature, having identified the most common skin problems in two groups of hospitalized patients.
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Hospitalización , Enfermedades Cutáneas Infecciosas/epidemiología , Enfermedades de la Piel/epidemiología , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derivación y Consulta , Estudios Retrospectivos , Enfermedades de la Piel/diagnóstico , Enfermedades Cutáneas Infecciosas/diagnósticoRESUMEN
Dilated cardiomyopathy (DCM) is a life-threatening disorder whose genetic basis is heterogeneous and mostly unknown. Five Arab Christian infants, aged 4-30 months from four families, were diagnosed with DCM associated with mild skin, teeth, and hair abnormalities. All passed away before age 3. A homozygous sequence variation creating a premature stop codon at PPP1R13L encoding the iASPP protein was identified in three infants and in the mother of the other two. Patients' fibroblasts and PPP1R13L-knocked down human fibroblasts presented higher expression levels of pro-inflammatory cytokine genes in response to lipopolysaccharide, as well as Ppp1r13l-knocked down murine cardiomyocytes and hearts of Ppp1r13l-deficient mice. The hypersensitivity to lipopolysaccharide was NF-κB-dependent, and its inducible binding activity to promoters of pro-inflammatory cytokine genes was elevated in patients' fibroblasts. RNA sequencing of Ppp1r13l-knocked down murine cardiomyocytes and of hearts derived from different stages of DCM development in Ppp1r13l-deficient mice revealed the crucial role of iASPP in dampening cardiac inflammatory response. Our results determined PPP1R13L as the gene underlying a novel autosomal-recessive cardio-cutaneous syndrome in humans and strongly suggest that the fatal DCM during infancy is a consequence of failure to regulate transcriptional pathways necessary for tuning cardiac threshold response to common inflammatory stressors.
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Codón sin Sentido , Péptidos y Proteínas de Señalización Intracelular/genética , Síndrome LEOPARD/genética , Síndrome LEOPARD/patología , Proteínas Represoras/genética , Animales , Células Cultivadas , Preescolar , Citocinas/metabolismo , Femenino , Fibroblastos/metabolismo , Técnicas de Silenciamiento del Gen , Humanos , Lactante , Lipopolisacáridos/toxicidad , Masculino , Ratones , Ratones Noqueados , Miocitos Cardíacos/metabolismoRESUMEN
BACKGROUND: The routine diagnosis of genodermatoses is significantly complicated by the fact that in this group of disorders, clinical manifestations may result from mutations in unrelated genes (genetic heterogeneity) and mutations in the same gene often lead to dissimilar clinical signs (phenotypic heterogeneity). METHODS: In this study, we applied the principles of homozygosity mapping as a screening method before formal mutational analysis in an attempt to facilitate the molecular diagnosis of genodermatoses in consanguineous families. The method was evaluated in a retrospective fashion in 4 families previously assessed with junctional epidermolysis bullosa and in a prospective manner in 11 families with congenital recessive ichthyosis. RESULTS: The method was found to be efficient in directing the molecular analysis to one of the 4 genes commonly involved in the pathogenesis of junctional epidermolysis bullosa or in identifying cases of congenital recessive ichthyosis caused by mutations in TGM1. We found that this diagnostic strategy results in a 5-fold decrease in the cost of mutation analysis. LIMITATIONS: The proposed diagnostic strategy is applicable to consanguineous families only and, therefore, cannot be used in outbred populations. CONCLUSION: Our results indicate that homozygosity mapping may serve as a useful adjunct in the molecular diagnosis of junctional epidermolysis bullosa or congenital recessive ichthyosis in inbred populations. This study emphasizes the usefulness in human genetics of diagnostic strategies tailored to the demographic features of target populations.
Asunto(s)
Mapeo Cromosómico , Consanguinidad , Epidermólisis Ampollosa de la Unión/genética , Pruebas Genéticas/métodos , Homocigoto , Ictiosis/genética , Secuencia de Bases , Epidermólisis Ampollosa de la Unión/diagnóstico , Genes Recesivos , Humanos , Ictiosis/diagnóstico , Mutación , Linaje , Estudios RetrospectivosRESUMEN
Congenital recessive ichthyoses represent a vast and markedly heterogeneous group of diseases that have been mapped to at least seven distinct chromosomal loci. In this study, we ascertained two consanguineous families presenting with congenital ichthyosis. Using homozygosity mapping, we identified a 6.5 cM homozygous region on 12p11.2-q13 shared by all affected individuals. Multipoint logarithm of odds ratio (LOD) score analysis placed the new locus between markers D12S345 and D12S390 with a maximum LOD score of 4.79 at marker CH12SSR13. This region harbors PPHLN1, encoding periphilin 1, a protein involved in the cornification process. No deleterious mutations were identified within the coding region of this gene, suggesting the existence of another gene associated with epidermal differentiation on 12p11.2-q13.
Asunto(s)
Cromosomas Humanos Par 12/genética , Ictiosis Lamelar/genética , Proteínas Nucleares/genética , Antígenos de Neoplasias , Mapeo Cromosómico , Humanos , Ictiosis Lamelar/patología , MutaciónRESUMEN
We report three female patients suffering from toxic epidermal necrolysis, with 30% to 70% epidermal detachment. Alleged causative agents were dipyrone, dibenzazepine, and allopurinol. All patients were treated by intravenous immunoglobulins (IVIG) and survived without further complications, although poor prognostic factors such as concomitant diabetes, large areas of epidermal detachment, and pancytopenia were present. We report these cases with emphasis on the concept that prompt diagnosis, withdrawal of causative drugs, and immediate treatment are imperative for the favorable outcome of the disease. Our patients can be added to the list of those patients who were successfully treated by IVIG, as indicated in this review of the literature.
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Inmunoglobulinas Intravenosas/uso terapéutico , Síndrome de Stevens-Johnson/terapia , Adulto , Femenino , Humanos , Síndrome de Stevens-Johnson/diagnóstico , Síndrome de Stevens-Johnson/fisiopatologíaRESUMEN
Bacterial skin infections are very common and trigger destruction of the skin integrity. Impetigo is a consequence of group A beta-hemolytic streptococcus or Staphylococcus aureus infection. The clinical presentation in general is very typical and empiric treatment is usually successful. In cases of close contacts such as between classmates, athletes, or soldiers, the prompt recognition and appropriate treatment of the infection may stop an epidemic. We report a group of six soldiers who shared the same military equipment (physical shields) during hand-to-hand combat training. All of the soldiers had skin lesions and two of them suffered from systemic symptoms. Group A beta-hemolytic streptococcus and S. aureus were cultured from the impetiginous lesions. All patients recovered after systemic and/or local antibiotic treatments. These cases emphasize the need for the maintenance of proper hygiene throughout the training program to prevent spread of the disease and the importance of rapid diagnosis by bacteriological identification.
Asunto(s)
Impétigo , Personal Militar , Enseñanza , Antibacterianos/uso terapéutico , Humanos , Impétigo/tratamiento farmacológico , Impétigo/etiología , Impétigo/fisiopatología , Israel , Masculino , Staphylococcus aureus/patogenicidadRESUMEN
Hyaluronic acid (HA) fillers in cosmetic medicine have been considered relatively safe, though fillers used in European countries and throughout the world are not necessarily approved by the Food and Drug Administration. As their use continues to expand worldwide, physicians in a wide range of medical specialties are authorized to perform HA injections, including general medicine practitioners and even dentists. An increasing number of reports have appeared regarding side effects to these products. It is now known that reactions to Hyaluronic acid are related not only to technical faults of the injections, but also to immune responses, including delayed hypersensitivity and granulomatous reactions. Herein, we describe five cases treated by a variety of treatment modalities, all with delayed reactions to different brands of hyaluronic acid fillers. As there is currently no standardization of treatment options of adverse effects, these cases accentuate the debate regarding the approach to the individual patient and the possible need for pre-testing in patients with an atopic tendency.
RESUMEN
The XPD protein plays a pivotal role in basal transcription and in nucleotide excision repair (NER) as one of the ten known components of the transcription factor TFIIH. Mutations in XPD can result in the DNA repair-deficient diseases xeroderma pigmentosum (XP), trichothiodystrophy (TTD), cerebro-oculo-facial-skeletal syndrome, and in combined phenotypes such as XP/Cockayne syndrome and XP/TTD. We describe here an 18-year-old individual with mild sun sensitivity, no neurological abnormalities and no tumors, who carries a p.R683Q mutation in one allele, and the novel p.R616Q mutation in the other allele of the XPD gene. We also describe four patients from one family, homozygous for the identical p.R683Q mutation in XPD, who exhibit mild skin pigmentation and loss of tendon reflexes. Three homozygous patients presented with late-onset skin tumors, and two with features of premature aging and moderate cognitive decline. Cells from the compound heterozygous individual and from one of the patients homozygous for p.R683Q exhibited similar responses to UV irradiation: reduced viability and defective overall removal of UV-induced cyclobutane pyrimidine dimers, implying deficient global genomic NER. Cells from the compound heterozygous subject also failed to recover RNA synthesis after UV, indicating defective transcription-coupled NER. Mutations affecting codon 616 in XPD generally result in functionally null proteins; we hypothesize that the phenotype of the heterozygous patient results solely from expression of the p.R683Q allele. This study illustrates the importance of detailed follow up with sun sensitive individuals, to ensure appropriate prophylaxis and to understand the mechanistic basis of the implicated hereditary disease.