Radiodermatitis as a consequence of radiation recall induced by acyclovir: case report

BackgroundRadiation recall dermatitis (RRD) is an inflammatory reaction in an area of the skin previously irradiated for cancer treatment. The reaction usually occurs following the administration of a cytotoxic drug. Manifestations range from mild to severe, resulting in tissue necrosis. It is treated with removal of the probable causative agent, daily dressings and surgical debridement of the necrotic area.Case presentationA 54-year-old woman had a previous diagnosis of intraductal carcinoma in situ, and had been submitted to lumpectomy and adjuvant radiotherapy and hormonal therapy. One year after surgery, sores suggestive of herpes zoster infection developed, and treatment with acyclovir was started. At the same time, there was the onset of pain and fever. In the skin area previously irradiated, there was breast hardening, skin infiltration and serosanguinolent discharge. An incisional biopsy was performed to rule out radioinduced sarcoma. The patient was treated with surgical debridement.ConclusionsThis case report describes acyclovir as a possible trigger of RRD, a rare condition that could have been mistaken for an eruption with other causes. In this case, the dermatitis reaction was confined to the previously irradiated area of the skin, which suggested radiation recall. A better understanding of the condition’s mechanism and about the possible joint effects of drugs and radiotherapy on the skin is necessary.     

Genetic polymorphisms of cytokine genes and risk for trichloroethylene-induced severe generalized dermatitis: A case-control study

Trichloroethylene (TCE)-induced severe generalized dermatitis (SGD) is considered to be a contact allergic disease and is dependent on a cell-mediated immune response. Little is known about its pathogenesis. Several lines of evidence suggest that tumour necrosis factor (TNF) and interleukin 4 (IL-4) are involved in the immunological and inflammatory reactions. To investigate the relation between polymorphisms of TNF and the IL-4 gene and the risk of TCE-induced SGD, a case-control study was conducted consisting of 111 patients diagnosed with SGD and 152 TCE-exposed workers without SGD. Polymerase chain reaction-restriction fragment length polymorphism was used to detect the polymorphisms of TNF-α (G-238A, G-308A), TNF-β (intron 1) and IL-4 (C-590T). Logistic regression was applied to calculate the odds ratios (OR) and 95% confidence intervals. The results reveal that the frequency of TNF α-308 wild allele in cases was significantly higher than that in control subjects (p=0.049). Individuals with a heterozygous genotype of TNF α-308 were associated with the decreased risk of TCE-induced SGD relative to the homozygous genotype (OR=0.398, 95% CI=0.164–0.967). No significant differences in the allele and genotype frequencies could be demonstrated at any other polymorphic loci among both groups. The finding of a possible contribution of a TNF-α genetic polymorphism is a primary result because the pathogenesis of TCE-induced SGD is complex and likely to involve the interaction of a number of genes. A further study should be conducted to illustrate the influence of a link between certain relevant alleles in the assessment of genetic susceptibility.     

Importance of tryptophan nitration of carbonic anhydrase III for the morbidity of atopic dermatitis

The nitration of proteins results from the vigorous production of reactive nitrogen species in inflammatory disease. We previously reported the proteomic analysis of nitrated tryptophan residues in in vitro model cells for inflammatory diseases using a 6-nitrotryptophan-specific antibody. In this paper, we applied this method to the analysis of a disease model animal and identified the 6-nitrotryptophan-containing proteins in the skin of atopic dermatitis model mice (AD-NC/Nga mice). We found three nitrotryptophan-containing proteins, namely, carbonic anhydrase III (CAIII), α-enolase (α-ENO), and cytoskeletal keratin type II (KTII), and identified the positions of the nitrotryptophan residues in their amino acid sequences: Trp47 and Trp123 in CAIII, Trp365 in α-ENO, and Trp221 in KTII. Among these, the nitration of CAIII was increased not only in the lesional skin of AD-NC/Nga mice but also in the mice that did not present any symptoms. The in vitro nitration of purified CAIII by peroxynitrite reduced its CO₂ hydratase activity in a dose-dependent manner. In addition, we found that CAIII was induced during the differentiation of normal human epidermal keratinocytes. Furthermore, we found the presence of CAIII and the formation of 6-nitrotryptophan-containing proteins in both the lesional and the nonlesional sections of the skin of patients with atopic dermatitis through immunohistochemical staining. This study provides the first demonstration of the formation of 6-nitrotryptophan in human tissues and disease.     

复方黄柏液联合夫西地酸软膏及西替利嗪 治疗面部糖皮质激素依赖性皮炎疗效观察

目的观察复方黄柏液联合夫西地酸软膏及西替利嗪治疗面部糖皮质激素依赖性皮炎（以下简称为面部激素性皮炎）的疗效。方法采用随机对照观察方法对108例面部激素性皮炎患者分成治疗组和对照组。治疗组使用复方黄柏液（湿敷）联合夫西地酸软膏（外用）,对照组用3%的硼酸溶液湿敷及维生素B6软膏外用;两组均口服西替利嗪片。2周为1个疗程,治疗2个疗程。结果治疗组有效率为80.77%;对照组有效率为56.86%。两组有效率比较差异有统计学意义（χ^2=7.16,P〈0.05）。结论复方黄柏液联合夫西地酸软膏及西替利嗪治疗面部激素性皮炎疗效好,无明显不良反应。     

Spawning-related fungal infection of golden galaxias Galaxias auratus (Galaxiidae)

The occurrence of golden galaxias Galaxias auratus with dermal fungal lesions in two populations was effectively modelled by the progression of gonadal stages of development. Skin lesions were found to be characteristic of fungal dermatitis and a Saprolegnia sp. was identified as the causative agent. Infection is probably linked to spawning-related factors and it is probable that saprolegniasis is associated with seasonal mortality.     

New pathogenic and therapeutic paradigms in atopic dermatitis

Atopic Dermatitis (AD) is a common inflammatory skin disease with increasing prevalence in industrialized countries. Up to one-third of adults with AD have moderate-to-severe disease, leading to a large, unmet need for effective treatments. While current therapeutics focus mainly on symptom control, major advances have been made in translational research, with the goal of developing drugs to eradicate disease.A translational revolution is now occurring in AD, similar to the one that has occurred in psoriasis over the past decade. Research has focused on elucidating immune pathways responsible for AD, including Th2, Th22, and Th17 pathways, with testing of immune antagonists specific to these axes. An IL-4R antagonist, dupilumab, is the first drug that shows great promise in phase II trials. By studying clinical and molecular responses following treatment with specific immune antagonists, our understanding of and ability to treat AD will expand.     

16S rRNA-based amplicon analysis of changes in the bacterial population in the lesions of papillomatous digital dermatitis in dairy cattle after topical treatment with allyl isothiocyanate

Papillomatous digital dermatitis (PDD) is a foot disease causing lameness in dairy cattle. It is regarded as a polymicrobial infection, although its etiology is not fully understood. PDD is treated by the topical or systemic administration of antibiotics such as lincomycin (LCM); however, the milk of the cows cannot be marketed during the treatment and withdrawal period due to the residual antibiotics in milk. Allyl isothiocyanate (AITC), an extract of Wasabia japonica (known as wasabi or Japanese horseradish) widely employed as a food additive, can be used as an alternative antimicrobial agent that overcomes this problem. We previously showed that AITC is as effective as LCM in PDD treatment. Here, using the samples obtained in the previous clinical study, we analyzed changes in the bacterial population in the PDD-associated microbiota after AITC treatment and compared those with that following LCM treatment by 16S ribosomal RNA (rRNA)-based amplicon analysis. Both treatments induced major changes in the bacterial population, and Treponema species, which have been regarded as the major causative agents of PDD, were efficiently eliminated by both agents. However, the AITC-treated samples exhibited higher diversity compared with pretreatment samples, but this trend was not observed for LCM treatment, probably reflecting different antibacterial activities of the two agents. Importantly, this analysis detected population changes before morphological changes in PDD lesions (clinical signs of healing) became evident, indicating that 16S rRNA-based amplicon analysis represents an efficient strategy for analyzing and monitoring the treatment efficiency of PDD as well as other polymicrobial diseases.     

Focus: Allergic Diseases and Type II Immunity: Intricate Relationship Between Adaptive and Innate Immune System in Allergic Contact Dermatitis

Allergic contact dermatitis (ACD) is a complex immunological allergic disease characterized by the interplay between the innate and adaptive immune system. Initially, the role of the innate immune system was believed to be confined to the initial sensitization phase, while adaptive immune reactions were linked with the advanced elicitation phase. However, recent data predicted a comparatively mixed and interdependent role of both immune systems throughout the disease progression. Therefore, the actual mechanisms of disease progression are more complex and interlinked. The aim of this review is to combine such findings that enhanced our understanding of the pathomechanisms of ACD. Here, we focused on the main cell types from both immune domains, which are involved in ACD, such as CD4⁺ and CD8⁺ T cells, B cells, neutrophils, and innate lymphoid cells (ILCs). Such insights can be useful for devising future therapeutic interventions for ACD.