Seven novel COL7A1 mutations identified in patients with recessive dystrophic epidermolysis bullosa from Mexico.

Recessive dystrophic epidermolysis bullosa (RDEB; OMIM #226600) is one of the most devastating subtypes of epidermolysis bullosa, a group of skin and mucous membrane blistering disorders often associated with extracutaneous manifestations. RDEB is caused by mutations in COL7A1, the gene encoding type VII collagen (C7), and to date over 700 different mutations in the 8835 nucleotides constituting the open reading frame or adjacent exon-intron boundaries of COL7A1 have been described. We used targeted next-generation sequencing to identify seven previously unreported mutations in a cohort of 17 Mexican patients who were diagnosed with RDEB based on clinical presentation and immunoepitope mapping. Our study expands the spectrum of mutations identified in this cohort, including those suitable for emerging therapies reliant on precise genotyping.

Clinical features of gingival lesions in patients with dystrophic epidermolysis bullosa: a cross-sectional study.

BACKGROUND: Gingival lesions in patients with dystrophic epidermolysis bullosa (DEB) are a common manifestation. However, their clinical features, frequency and severity are currently unknown. METHODS: Forty-five DEB patients were assessed by an oral medicine specialist, who analysed the presence/absence of four clinical signs (erythema, erosion/ulcer, atrophy, blister) on free and attached gingiva, using the Epidermolysis Bullosa Oropharyngeal Severity score. RESULTS: Twenty-eight (62.2%) out of 45 DEB patients showed different types of gingival lesions, whose presence/absence and total frequency/distribution were not significantly different between males and females (p=0.087 and p=0.091, respectively). Erythema was the most prevalent lesion (66.2%) and the recessive DEB severe generalized (RDEB-sev gen) reached the highest median disease activity score. A significant correlation was observed between the DEB subtypes and the disease activity median score (p<0.001), but not between age and total disease activity score in each group of DEB (p>0.05). Lastly, logistic regression showed that only gender (p=0.031) and RDEB-sev gen (p=0.001) were risks factors for the presence of gingival lesions. CONCLUSIONS: Gingival lesions in DEB patients are a relatively common entity and may have multiple clinical aspects, emphasizing the need for thorough attention and awareness among dentists.

Genotype-oropharyngeal phenotype correlation in Mexican patients with dystrophic epidermolysis bullosa.

Previous investigations have attempted to correlate the genotype with the cutaneous phenotype in patients with epidermolysis bullosa (EB), but never with the oropharyngeal phenotype. Seventeen dystrophic EB (DEB) patients were genotyped for COL7A1 gene mutations and divided into five distinct groups. Oropharyngeal disease severity was assessed with the Epidermolysis Bullosa Oropharyngeal Severity (EBOS) score by an oral medicine specialist. The genotype-phenotype correlation was calculated by Kruskal-Wallis analysis of variance using the Mann-Whitney test, applying the Bonferroni correction. The most severe oropharyngeal phenotype was found in the group with the 2470insG/3948insT mutation, with a mean disease severity score of 18.50 ± 2.12; the mildest was found in the 6862del16 mutation group, with a mean disease severity score of 0.57 ± 1.13. The most significant difference in median score was found in the total score (P = 0.009), followed by tongue (P = 0.02) and upper lip (P = 0.021), but no correlation was found between disease severity and the groups (P>0.005, after Bonferroni correction). Multiple comparisons among the five different genotypic groups revealed no statistically significant genotype-oropharyngeal phenotype correlation; it was not possible to establish which group was more severe, or to associate a specific mutation to a specific oropharyngeal phenotype.

Snapshot of Quantiferon TB gold testing in Northern Mexico.

Most people infected with Mycobacterium tuberculosis have an asymptomatic condition named latent tuberculosis. These people do not have bacilli in the corporal secretions and are hard to diagnose by conventional laboratory tests. Diagnosis of latent tuberculosis infection (LTBI) in México is based on the tuberculin skin test (TST). This test has disadvantages, principally because the vaccine containing the Bacille Calmette-Guérin (BCG) is applied to 99% of this population and causes false positive TST outcomes. Recently, interferon-gamma release assays (IGRA) have been demonstrated to be a good test to detect latent tuberculosis with equal or better sensitivity to TST and without interference from BCG. However, in México the IGRA are an uncommon test due to the higher cost compared to TST. The main objective of this work was demonstrate the potential utility of the Quantiferon TB(®) gold in tube (QTB(®)-GIT) test to detect latent TB in a population from northern México. Samples from 106 subjects with close contact, or without contact, with actively infected TB patients were tested to detect LTBI. Our results show a significant difference between individuals in close contact with active TB patients (39.7%) compared to those without contact (3.2%), p < 0.01. The concordance between TST and QTB(®)-GIT was poor (κ = 0.31). Our preliminary results show that the QTB(®)-GIT has better capacity than TST to detect latent tuberculosis infection.