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Other Reactions from Gloves
Published in Robert N. Phalen, Howard I. Maibach, Protective Gloves for Occupational Use, 2023
T. Bullock, A. Sood, J.S. Taylor
Chemical leukoderma may be difficult to differentiate from idiopathic vitiligo.23 While chemical leukoderma is limited to the part of the body exposed to the chemical agent, idiopathic vitiligo most commonly causes lesions that are symmetrically distributed on the dorsal hands and forearms and around the mouth and eyes. Idiopathic vitiligo usually occurs in the second decade of life, and patients often have a family history of similar lesions.97 The “mode of spread may be helpful for diagnosis—a history of gradual coalescence of small discrete macules, rather than the development of large macules with perifollicular sparing suggests chemical leukoderma.”20 Scalp hair is rarely involved, and eye color does not change. The period for exposure ranges from two weeks to approximately six months.23 Depigmentation is not always preceded by inflammation of the affected skin but is frequently associated with allergic contact dermatitis to the same chemical responsible for the pigment loss, although the latter is not a prerequisite.16 The absence of preceding inflammation may be explained by the resistance of some idiopathic vitiligo patients to developing a contact allergy in depigmented skin sites.24 Wood's light examination of the skin in a dark room may identify areas of leukoderma not obvious on routine visual inspection of the skin.
Disorders of Pigmentation
Published in Ayşe Serap Karadağ, Lawrence Charles Parish, Jordan V. Wang, Roxburgh's Common Skin Diseases, 2022
Michael Joseph Lavery, Charles Cathcart, Hasan Aksoy
Clinical presentation: Individuals present with well-defined patches of depigmentation. Any anatomic site may be affected, but periocular, perioral, and acral site involvement confers a poor response to treatment. The affected patches of skin are symmetric and located on sun-exposed sites or in skin creases (Figure 25.2). Different patterns have been described, including segmental, nonsegmental, mixed, and unclassified.
Myths in Vitiligo
Published in Vineet Relhan, Vijay Kumar Garg, Sneha Ghunawat, Khushbu Mahajan, Comprehensive Textbook on Vitiligo, 2020
Vitiligo is a common acquired depigmentation disorder affecting around 3%–4% of the general Indian population [1] and 0.5% of the world's population [2]. In this autoimmune condition, depigmentation is caused by the loss of functional melanocytes from the affected area of the epidermis. Although the exact etiology is still obscure, the following hypotheses have been put forward: autoimmune, neural, self-destruct, polygenic, and multifactorial [2–4]. Of all these, the autoimmune etiology seems most plausible.
In Vivo Confocal Microscopic Evaluation of the Limbus and Cornea in Vogt Koyanagi Haradas Syndrome
Published in Ocular Immunology and Inflammation, 2022
Radhika Thundikandy, Gowri Priya Chidambaranathan, Naveen Radhakrishnan, Rathinam S. R
Vogt Koyanagi Harada Syndrome(VKH) is multi system disorder characterized by bilateral granulomatous pan uveitis with exudative retinal detachments and associated with neurological and cutaneous manifestations.1 It is considered to be a cell-mediated autoimmune disease directed against melanocytes and therefore tissues that have melanocytes like skin, eye, ear, and meninges are affected. In the acute stage of the disease the patients present with keratic precipitates, cellular reaction in the anterior chamber, and exudative retinal detachments. As the disease progresses into the convalescent stage diffuse depigmentation of the choroid sets in along with retinal pigment epithelium migration leading on to diffuse fundus depigmentation and an orange red discoloration.2 The palisades of Vogt (POV) at the limbus gradually lose pigmentation in some patients till the Saguira sign set in when the depigmentation is complete.3 Depigmentation is also seen to involve the integuments like skin, hair causing vitiligo and poliosis.
Cosmetic skin lightening use and side effects
Published in Journal of Dermatological Treatment, 2022
Natasha Masub, Amor Khachemoune
Cosmetic skin lightening, also known as skin bleaching, is the depigmentation of skin through the use of lotions, soaps, and oral products. The use of cosmetic, non-medical skin depigmentation is a common practice among darker skinned individuals both in the US and worldwide (5). From the dermatologist’s perspective, skin lightening products are important treatments for melasma and other pigmentation disorders. However, addressing the cosmetic use of these products may be challenging for dermatologists with their patients of color. A blanket recommendation to avoid all cosmetic skin lightening products is ineffective without first understanding the cultural and social forces that motivate their use. Further, many patients may turn to social media about skin bleaching, but recently published data has demonstrated these platforms rarely mention harmful effects of cosmetic skin lightening (6). To our knowledge, there has been only one study evaluating social media health information on cosmetic skin lightening. Basch and colleagues found there is a wide range of health information on skin bleaching on popular social media platform YouTube, but very few videos mention the potential harmful side effects (6). Thus, it is imperative that dermatologists be knowledgeable about the cultural context behind cosmetic skin lightening, products available, proper use, and side effects. This review article aims to serve as a primer for the dermatologist on the history, prevalence, active ingredients, and health implications of skin lightening products.
Nanoparticles as a potential teratogen: a lesson learnt from fruit fly
Published in Nanotoxicology, 2019
Bedanta Kumar Barik, Monalisa Mishra
Flies hatched after NP treatment has decreased body proportion (Panacek et al. 2011). Reduced body weight is observed after exposure to certain NPs. Phenotypic defect including depigmentation (Figure 4(A)) and soft cuticle were also reported in the offspring after AgNP treatment (Gorth et al. 2011; Key et al. 2011; Posgai et al. 2011). Soft cuticle is further co-related to reduced locomotory behavior in various studies (Wright et al. 1976; Walter et al. 1991; Neckameyer et al. 2001; Drapeau et al. 2003; Suh and Jackson 2007; Armstrong et al. 2013). The depigmentation occurs either due to altered melanin synthesis or with increased hsp70 expressions (Denman et al. 2008; Galván and Alonso-Alvarez 2009; Glassman 2011). Ag NP exposure further decreases the copper level which is a co-factor for tyrosinase and Cu-Zn superoxide dismutase; subsequently, production of these two enzymes is decreased. Tyrosinase is responsible for the synthesis of melanin and thus resulted demelanization (Wright 1987). Enzymes involved in dopamine metabolism (a pathway involved in melanin synthesis) are encoded by genes such as pale, yellow, Dopa decarboxylase (Ddc), and ebony (Sugumaran et al. 1992; Qian et al. 2002; Wittkopp et al. 2003; Carroll 2005; Sugumaran 2009; Tang 2009; Wittkopp and Beldade 2009).