Junctional epidermolysis bullosa: diagnosis and management of a patient with the Herlitz variant

BP180 dysfunction triggers spontaneous skin inflammation in mice

BP180, also known as collagen XVII, is a hemidesmosomal component and plays a key role in maintaining skin dermal/epidermal adhesion. Dysfunction of BP180, either through genetic mutations in junctional epidermolysis bullosa (JEB) or autoantibody insult in bullous pemphigoid (BP), leads to subepidermal blistering accompanied by skin inflammation. However, whether BP180 is involved in skin inflammation remains unknown. To address this question, we generated a BP180-dysfunctional mouse strain and found that mice lacking functional BP180 (termed ΔNC16A) developed spontaneous skin inflammatory disease, characterized by severe itch, defective skin barrier, infiltrating immune cells, elevated serum IgE levels, and increased expression of thymic stromal lymphopoietin (TSLP). Severe itch is independent of adaptive immunity and histamine, but dependent on increased expression of TSLP by keratinocytes. In addition, a high TSLP expression is detected in BP patients. Our data provide direct evidence showing that BP180 regulates skin inflammation independently of adaptive immunity, and BP180 dysfunction leads to a TSLP-mediated itch. The newly developed mouse strain could be a model for elucidation of disease mechanisms and development of novel therapeutic strategies for skin inflammation and BP180-related skin conditions.

Dressings used in epidermolysis bullosa blister wounds: a review

There is little rigorous evidence on the management of epidermolysis bullosa, so management is based on the patient's and clinician's preferences. However, there is a consensus that advanced dressings help promote healing and reduce pain.

Connective tissue and related disorders and preterm birth: clues to genes contributing to prematurity

To identify candidate genes contributing to preterm birth, we examined the existing literature on the association between known disorders of connective tissue synthesis and metabolism and related diseases and prematurity. Our hypothesis was that abnormal matrix metabolism contributes to prematurity by increasing risk of preterm premature rupture of membranes (PPROM) and cervical incompetence. Based on this review, we identified gene mutations inherited by the fetus that could predispose to preterm birth as a result of PPROM. The responsible genes include COL5A1, COL5A2, COL3A1, COL1A1, COL1A2, TNXB, PLOD1, ADAMTS2, CRTAP, LEPRE1 and ZMPSTE24. Marfan syndrome, caused by FBN1 mutations, and polymorphisms in the COL1A1 and TGFB1 genes have been associated with cervical incompetence. We speculate that an analysis of sequence variation at the loci noted above will reveal polymorphisms that may contribute to susceptibility to PPROM and cervical incompetence in the general population.

Tracheolaryngeal Complications of Inherited Epidermolysis Bullosa: Cumulative Experience of the National Epidermolysis Bullosa Registry

OBJECTIVES/HYPOTHESIS

To accurately determine the frequency with which complications arise in the ears, noses, and throats of patients with inherited epidermolysis bullosa (EB) as well as the cumulative risk of tracheolaryngeal stenosis or stricture.

STUDY DESIGN

Cross-sectional study (3,280 patients) with a nested, randomly sampled longitudinal subcohort (n=450), representing data collection, stratified by major EB subtype, of the National EB Registry, an epidemiologic project focused on enrolling all EB patients within the continental United States from 1986 to 2002, to permit generalization of findings to the entire American EB population.

METHODS

Systematic epidemiologic case finding and data collection were performed throughout the continental United States, followed by subclassification of patients by EB subtype. ENT complications were quantified via contingency tables (as frequencies) and lifetable analyses. Frequencies of surgical procedures were also determined.

RESULTS

The most important clinical ENT complication in inherited EB was tracheolaryngeal stenosis or stricture, arising during early childhood and primarily within infants and children with junctional EB (JEB) (cumulative risk of 39.8% and 12.8% in Herlitz and non-Herlitz JEB, respectively, by ages 6 and 9). Other uncommon complications included chronic otitis media, chronic otitis externa, and hearing loss.

CONCLUSIONS

Given the potential risk for sudden airway occlusion and death, meticulous surveillance by a pediatric otolaryngologist is a critical part of the overall management of infants and children with EB, especially those with JEB and two rare subtypes of generalized EB simplex. Elective tracheostomy should be considered in EB infants and children with evidence of airway embarrassment.

Herlitz junctional epidermolysis bullosa presenting at birth with anonychia: a case report and review of H-JEB

A 15-day-old Yemeni boy presented with anonychia and granulomatous nail beds and white patches in the mouth. Biopsy specimens from the nail beds were nondiagnostic. Shortly thereafter the child developed multiple tense bullae, a hoarse voice, and poor appetite. Hematoxylin and eosin staining along with monoclonal antibody studies of a skin biopsy specimen revealed subepidermal bullae through the lamina lucida and a marked decrease in laminin 5. A diagnosis of junctional epidermolysis bullosa Herlitz variant was made. His course was complicated by multiple nonhealing wounds, oral pharyngeal involvement, sepsis, anemia, and poor nutrition, leading to his eventual death. This report emphasizes the unusual presentation of Herlitz junctional epidermolysis bullosa with anonychia as the initial finding and a relatively prolonged period before cutaneous blister formation, resulting in delay of diagnosis.

Junctional epidermolysis bullosa gravis (Herlitz): diagnostic and genetic aspects

We report on a boy suffering from lethal junctional epidermolysis bullosa gravis (JEBH) (Herlitz-type) (OMIM 226700). Screening for mutations of LAMB3 gene with polymerase chain reaction (PCR) amplification of all exons from genomic DNA and subsequent heteroduplex analysis and dideoxynucleotide sequencing of heteroduplex forming PCR products disclosed two mutations: the recurrent maternal mutation R635X and the novel paternal mutation 1629insG, both in exon 14 of LAMB3. Both mutations lead to a premature termination code, non-sense mediated mRNA decay and to absence of the synthesis of the beta3 chain of laminin 5. During the mutation screening of the index patient a second pregnancy was ascertained. After amniocentesis (14 + 1 week of pregnancy), prenatal diagnosis from fetal cells was performed and compound heterozygosity for both mutations was evident. The consultants decided to have a termination of pregnancy shortly after the diagnosis. Remarkable skin fragility of the fetus was evident by clinical examination. Complete absence of laminin 5 could be demonstrated by immunofluorescence staining. By the third pregnancy of this couple so far screened for mutations by chorionic villus sampling for prenatal molecular diagnosis a healthy but heterozygous child is expected.