Corynebacterium ulcerans and C. ovis. In addition to diphtheria toxin, lysogenic C. ulcerans and C. ovis strains each produce their own specific toxin; they also maintain their specific morphology and urease production whilst C. diphtheriae strains lysogenized by C. ulcerans phagesproduce only diphtheria toxin. The majority of C. ulcerans phages are unable to induce the production of diphtheria toxin in strains of C. ulcerans.Phage typing with Corynebacterium ulcerans phages is a practical possibility. Thirteen well-defined phage types were established by this technique in 172 C. ulcerans and 62 C. ovis strains with only one of the phage types (111 C) occurring in both species. C. ulcerans can be distinguished from C. ovis by the pathogenicity test in mice. C. ovis kills mice by any route of inoculation whilst C. ulcerans strains cause only arthritis. C. ulcerans wild strains could be identified in this way and C. ulcerans and C. ovis strains from different type culture collections could be distinguished from each other by these well-defined characteristics.
Pemphigoid nodularis (PN) is a rare clinical variant of bullous pemphigoid characterized by the presence of nodular prurigo-like lesions and pemphigoid blisters. The diagnosis is confirmed by direct immunofluorescence (DIF)/ indirect immunofluorescence (IIF) and immunoserology tests. For some patients, with long mean duration of symptoms, the correct diagnosis of PN is delayed because the disease is not recognized. We present a case and summarize the reported characteristics of PN. The search in MEDLINE database, after selection, resulted in 36 articles presenting 47 cases of PN. Between published cases a female predominance was noted (female to male ratio of 1.8:1), almost half of the reported patients were non-Caucasian, and the mean age at presentation was 66.2 years. The mean duration until the diagnosis was almost 2 years. Sixteen patients also had other autoimmune diseases. Twenty-two patients developed vesicles/bullae/urticarial plaques before or after the diagnosis. Peripheral eosinophilia and high levels of serum total IgE were reported in 10.6 and 27.2% of patients, respectively. ELISA for either BP180, BP230 or both were positive in all tested cases. DIF and IIF microscopy were positive overall in 100 and 92.3% of cases, respectively. Corticosteroids, either topical or systemic, were the most efficient therapeutic option, although many others were used. PN remains a diagnostic and therapeutic challenge in elderly patients with unexplained refractory chronic pruritus associated with papulo-nodular lesions.
Psoriasis is a chronic, systemic, inflammatory disorder which accelerates the life process of skin cells, based on a genetically induced deviant immune response. High-frequency ultrasonography (HF-USG) is a painless, non-invasive imaging technique that can be performed and repeated whenever the need arises. We evaluated lesional and non-lesional skin of psoriatic patients with the use of HF-USG, focusing on the immune-induced inflammation and skin thickness. Previous studies suggested that HF-USG, being a non-invasive technique, is useful as an aid to clinical evaluation of the severity of psoriatic plaques. Our goal was to determine whether the skin of psoriatic patients is influenced by the background or habits of the patients. The study included a total of 27 patients affected by psoriasis vulgaris. The thickness of the epidermis and dermis and the skin echogenicity were documented for the active plaques, as well as for the non-affected skin of all the patients included in the study, using a high-frequency ultrasonographic system. The patient's local background, sex, family history of psoriasis, smoking habits and sun exposure were analyzed. HF-USG of the psoriatic plaques exposes a three-band structure that is easily distinguished from the surrounding unaffected skin, due to a hypoechoic band in the upper dermis. Although not specific for psoriasis, it is a strong marker of inflammation. The obtained results confirm that, indeed, skin thickness is greater in lesional skin compared to non-lesional skin, by a mean of 1,180 µm (±340 µm). We consider that skin HF-USG should be used as a quantitative method in the clinical evaluation of the patients with psoriasis and may help as an objective means of assessing inflammation in lesional skin.
Psoriasis vulgaris is a chronic inflammatory dermatosis with major impact on patients' life quality. The etiopathogenesis is multifactorial, depending on complex interactions between genetic and environmental factors.We
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