Airborne contact dermatitis from unexpected exposure to rosin (colophony)

We report 3 cases of contact dermatitis in rosin-sensitive individuals caused by exposure to airborne rosin components from different sources. Case no. 1 was a female office worker with a facial dermatitis caused by rosin components which emanated from the linoleum floor covering in her office. Floor material containing wood flour and rosin was released into the air, causing a facial dermatitis in the rosin-sensitive subject. Case no. 2 involved a woman who worked in a factory producing dairy product cartons and had a dermatitis on her lower legs, lower arms and upper chest. Her dermatitis was caused by dust from the paper cartons and contact allergy to rosin components probably aggravated her dermatitis. Case no. 3 was a female office worker with a relapsing dermatitis on her eyelids. Her dermatitis was caused by a rosin-containing floor polish, which was seen as a powder on the office floor. Extracts of suspected material and products were patch tested and analysed for the presence of rosin components with HPLC and GC techniques. A discussion and recommendations on chemical analyses of rosin components follow. We conclude that a thorough investigation, including chemical analyses, can rule out non-specific diagnoses and offer a solution to the patient's skin problems.     

中国特应性皮炎诊疗指南（2020版）

【摘要】 特应性皮炎以反复发作的慢性湿疹样皮疹为主要表现，伴有显著的皮肤干燥和瘙痒。随着生活方式和环境的改变，近10余年间我国特应性皮炎的发病率不断升高，受累及的人群涉及各年龄段。本指南结合近5年特应性皮炎的研究进展，在2014版中国特应性皮炎诊疗指南的基础上予以进一步的补充和完善，对特应性皮炎的定义、患病率、发病机制、分类、诊断、预防和治疗进行更新，可为特应性皮炎的诊疗提供科学和权威的参考依据。     

Allergic contact dermatitis from ethyl chloride and sensitization to dichlorodifluoromethane (CFC 12)

Despite the widespread use of ethyl chloride as a local anesthetic and chlorofluorocarbons as propellants in medical and cosmetic aerosols, contact allergy to these 2 gases is rare. In a 30-year-old woman, an unusual itchy dermatitis appeared at all skin sites where a medical aerosol containing ethyl chloride had been briefly applied. Subsequent re-exposure to the spray and patch tests revealed contact sensitization to ethyl chloride and dichlorodifluoromethane (CFC 12). Histologic and immunohistochemical examinations of the test reaction were consistent with a T-cell-mediated allergic reaction. The low incidence of contact allergy to ethyl chloride and chlorofluorocarbons may be due to the rapid evaporation of these volatile gases, thus preventing intense and prolonged contact with the skin and consequently contact sensitization. A modified patch test procedure using perforated plastic chambers to allow gas evaporation is necessary to test volatile agents.     

Stereospecificity of allergic contact dermatitis (ACD) to enantiomers

Summary Guinea pigs were sensitized to polygodial 1, a natural sesquiterpene dialdehyde, using intradermal injections in Freund's complete adjuvant.Cross-reactions with a (±)-mixture of warburganal and (-)-warburganal 2 (a natural hydroxylated derivative of polygodial) showed a high specificity of the allergic response since the (-)-pseudoenantiomer (having the same configuration as the primary sensitizer) gave a stronger skin reaction than the racemic mixture.     

黄连等单味中药对人型支原体的药敏试验

由于中草药具有褐色、黑色等颜色,给人型支原体液体培养药敏试验的结果判断带来一定的困难。我们对黄连等单味中药进行液体加固体培养作人型支原体药敏试验,并检测敏感中药体外最小抑菌浓度,为中药对支原体体外药敏试验提供了一种方法.     

An outbreak of contact dermatitis from Rhus verniciflua (Toxicodendron vernicifluum)

Case reports are described of individuals who developed acute contact dermatitis after contact with the resin from the Rhus verniciflua (Toxidendron vernicifluum). Potential problems from possible extensive urban planting of this species are discussed.     

Sex differences in susceptibility to development of contact hypersensitivity to dinitrochlorobenzene (DNCB)

We have investigated the differences between the sexes in the development of contact sensitivity induced by dinitrochlorobenzene (DNCB). Ten male and 12 female subjects were sensitized with DNCB (30 micrograms applied on a 1 cm patch test disc) and challenged 1 month later with doses of 8.8, 12.5, 17.7 and 25 micrograms. The responses were measured after 48 h as increase in skinfold thickness with Harpenden callipers. Females showed a larger response at all challenge doses studied, and the slope of the log-dose response curve was significantly steeper in females. We conclude that there are significant differences in delayed type hypersensitivity between males and females.     

中国特应性皮炎诊疗指南（2020版）解读

 特应性皮炎是一种常见的慢性、复发性、炎症性、瘙痒性皮肤病,严重影响患者生活质量。近年来国内外AD研究进展迅速,为了进一步规范和指导AD的诊断和治疗,中华医学会皮肤性病学分会免疫学组和特应性皮炎协作研究中心组织相关专家对原指南进行了修订。本文就2020年版《中国特应性皮炎诊疗指南》中更新部分作一简要解读。     

Atopic dermatitis: a histologic and radioautographic study (after 3H-thymidine labelling) of epidermal and dermal lesions (author's transl)]

Skin lesions of atopic dermatitis (A. D.) have been studied histologically and radioautographically after in vitro incorporation of tritiated thymidine. The histopathologic aspects of epidermis in the different types of skin lesions are reviewed. The dermal infiltrate is mononuclear and not very abundant in all types of lesions. An enlargement of the epidermal proliferative compartment has been noticed. Labelled cells are distributed as follows (mean +/- standard deviation) : 46 +/- p. 100 in the basal layer; 37 +/- 6 p. 100 in the epibasal layer; 16 +/- 7 p. 100 in the upper layers. The basal and epidermal labelling indices have been found significantly increased in exudative and lichenified lesions as compared to xerotic areas and normal epidermis. The labelling index of the "round" cell infiltrate in the dermis was significantly higher than in irritant patch test reactions (p less than 0.001) but significantly lower than in allergic positive patch test reactions (p less than 0.001). This increased cell proliferation in the dermal infiltrate does not allow definite conclusions about immunopathogenesis of the disease: indeed, a large number of mediators, involved in the inflammatory reactions of A. D. lesions, can modulate cell proliferation.     

Concomitant development of photoallergic contact dermatitis from ketoprofen and allergic contact dermatitis from menthol and rosin (colophony) in a compress

We describe a case of a 40-year-old non-atopic woman with recurrent leg ulcers because of the factor V Leiden mutation who developed a severe eczematous lesions of the skin surrounding an ulcer of the right leg after the use of a protease-modulating matrix (Promogran, Johnson and Johnson, Gargrave, Skipton, UK). The patient was patch tested with the SIDAPA (Italian Society of Allergological, Occupational and Environmental Dermatology) standard series, a piece of the device as is, of the bovine collagen (Zyderm, Collagen Corporation, Palo Alto, CA, USA) as is, a piece of the gauze containing only regenerated oxidized cellulose (Tabotamp, Johnson and Johnson, Gargrave, North Yorkshire, UK) and of a fold towels in pure cellulose (Foscart, Bassano del Grappa, Italy). Patch tests gave a positive reactions to nickel sulphate and Promogran as is. We showed that the sensitizing agent was regenerated oxidized cellulose, a substance the treatment of ulcers and as is in and in combination with collagen in surgery for intraoperative hemostasis. The case reported suggests that regenerated oxidized cellulose can cause allergic contact dermatitis.