PT has been and still is the gold

PT has been and still is the gold standard in diagnosing ACD. However, a negative PT result could not always exclude ACD. First, the European standard series only contains limited allergens, and the ingredients listed on the products are not frequently covered by the European standard series, thus confirmation of cosmetic ACD by a positive PT result to ingredients present in cosmetics could not always be achieved. Second, patch testing with patients\' own products is also very important, however, it fda approved is unrealistic for all the patients to take their suspected materials to the clinic in real clinical practice, and a negative result with a patient\'s own product does not exclude contact allergy to some of its components. Third, PT might yield false-negative result that is influenced by some factors, such as allergen concentration, vehicle, the responsiveness of the patient, etc. Considering the above, if a positive PT is mandatory in diagnosing ACD, some ACD cases would be missed. Other tests, such as usage test and repeated open application test are also valuable in diagnosing ACD. The percentage of seasonal FD was 9.0%, in which aeroallergens might play a role. Liu\'s study of 55 cases of seasonal FD in south China suggested that seasonal pollen might be one of the causative agents. In our study, atopic dermatitis only accounted for 2.2% of FD, this may be partly because most of our patients were adults and partly because patients with atopic dermatitis did not always undergo PT in our clinics. The low prevalence of atopic dermatitis (0.70% in students aged 6–20 years) in China may also have contributed to this finding. More FD patients experienced sunlight aggravation than non-FD patients, which was probably due to the face being exposed to more sunlight than other body sites. A study in the UK showed that 15.6% of schoolchildren with atopic dermatitis perceived rash exacerbation to sunlight exposure (sites not mentioned). In a university hospital in Korea, 50% of head and neck atopic dermatitis patients reported aggravation by sun exposure. A study in Japan showed that 55.4% of adult atopic dermatitis experienced an exacerbation of the facial lesions after sun exposure. However, that sunlight-induced exacerbation of dermatitis contrasted with therapeutic use of ultraviolet was a paradox. The paradox was also seen in psoriasis, in which phototherapy was a standard therapy, but some psoriasis patients aggravated in summer and these patients usually responded poorly to phototherapy. Some unknown endogenous factors may contribute to the difference and need to be studied further. In China, beef or lamb, seafood, spicy food and alcohol have been believed to be rash-inducing or aggravating foods for thousands of years. Some patients did experience dermatitis exacerbation by taking these foods in our study (Table 3), which did not seem to be caused by food allergy, since no other allergic symptoms were found. More FD patients experienced dermatitis exacerbation by ingestion of spicy food or alcohol, vasodilatation effects might contribute a part. A study on ethnic variations in self-perceived sensitive skin showed that Asians appeared to have greater facial skin reactivity to spicy food, it has also been reported that about 83% of Orientals were alcohol facial flushers, thus genetic factors might also be involved. In our study, environmental humidity did not show significant roles between the facial and nonfacial group, >20% of patients claimed aggravation by lower humidity and <10% patients claimed aggravation by higher humidity in both groups (Table 3). It was reported that higher humidity might be associated with poorly controlled children eczema in the USA, the author explained that warm and humid weather promotes the evaporation of water on the skin surface, which may further exacerbate skin dryness.
Introduction Dermoscopy is a noninvasive diagnostic method that has been widely recognized as a useful method for assessing and monitoring patients with pigmented and nonpigmented skin tumors. Dermoscopy is beneficial for the evaluation of vascular and pigmented structures that are not visible clinically, and has also been reported to be a useful tool for the early recognition of malignant melanoma. In recent years, its applicability has also been extended to the field of inflammatory skin disorders. However, the dermoscopic features of common inflammatory dermatoses are not well studied, and limited data about their features are currently available. Lichen planus (LP), an inflammatory skin disorder, is a well-characterized dermatological condition that affects the skin, mucosa, hair, and nails, and is characterized by discrete, violaceous, polygonal papules. The surface of LP lesions may exhibit white lines in a variable configuration, also known as Wickham striae (WS). A nonvascular feature (whitish striae) is the most significant and typical dermoscopic finding in LP. The dermoscopic features of LP also include gray-blue dots, comedo, milium-like cysts, and vascular structures (red lines). Although previous studies have demonstrated typical patterns of LP, we have observed atypical dermoscopic findings without WS in patients who had been diagnosed with LP by histopathologic examination and evaluated the correlation between dermoscopic patterns and histopathologic findings.