Dystrophic epidermolysis bullosa: two case reports.

We identified the mutations in two patients with different phenotypes of dystrophic epidermolysis bullosa (DEB). We performed molecular diagnosis to a patient aged 45 years who showed the typical severe generalized autosomal recessive DEB signs when admitted to the hospital. The other patient is a 4-month-old boy who showed a moderate clinical aspect of DEB, dominated by nail dystrophy. The molecular diagnosis disclosed in the first patient the presence of a heterozygous mutation consisting of a nucleotide substitution that lead to a splice site mutation, namely 425-2 A>G, associated to a premature termination codon, in exon 5, namely c.553 C>T, p.R185X and in the second patient a heterozygous substitution at nucleotide position 6100 that converts a glycine amino acid to arginine (6100G>A). The mutation is designated G2034R. We conclude that molecular diagnosis is the conclusive EBD investigation, maps the phenotype of a patient with his genotype and thus allows a better understanding of the disease mechanism and the development of gene therapy. Molecular diagnosis also enables genetic counseling and prenatal diagnosis.

His-Purkinje waveforms on externally recorded averaged unfiltered electrocardiograms.

Electrocardiographic signal recorded in right unipolar leads (2V1, 3V1, V1) was amplified (up to 500,000 times) averaged (256 or 512 cardiac cycles) and finally digitally filtered, in order to record His-Purkinje (HP) activity. A group of 41 patients with sinus rhythm and PR intervals ranging between 100 and 250 ms was repeatedly investigated. Distinct and highly reproducible waveforms located in the PR segment, attributable to HP activity, were recorded on the averaged unfiltered traces in 14 patients (34%). Waveforms, with an amplitude ranging between 4 and 80 microV, were positive in 13 patients and negative in one. In one patient, with atrial tachycardia with 2:1 atrioventricular block, two positive successive deflections suggested the possibility of recording the proximal and distal His activity. Externally recorded averaged unfiltered traces could be useful for the investigation of HP activity in a relatively large proportion of patients.