LAUSR

Dear Editor, Granuloma annulare (GA) is an inflammatory skin disease of unknown etiology. In most cases, it affects children and young adults. Clinically, the classic cutaneous lesions are represented by small pinkish nodules, mainly involving the areas of backs of the hands or around the joints. Plaques of GA are usually concentrically arranged. Sometimes, a disseminated type of GA is found. There are two advanced tools that are helpful in the diagnosis of inflammatory diseases, including GA: dermoscopy and reflectance confocal microscopy (RCM) in vivo. A few studies have described dermoscopic features of GA, albeit no one has established a pattern in RCM. Here, we report features of GA in RCM based on two patients with clinically and dermoscopically diagnosed GA. Both patients gave their written informed consent. The study was performed according to the Declaration of Helsinki. A 45-year-old woman was referred to our clinic with the presence of three lesions located on the skin of the back of the left hand. Clinically, there were pinkish, slightly firm plaques several millimeters in diameter, located on the skin of the left hand back (Figure 1A). Itching and other types of symptoms did not occur. Personal history was negative. The patient had no other treatment before visiting our clinic. Dermoscopy revealed yellowish-orange structureless areas with dotted vessels sparsely distributed (Figure 1B). The RCM examination of the epidermis showed typical honeycombed pattern and tops of papillae with dilated vessels in the spinous layer (Figure 1C). Debris of keratinocytes and inflammatory cells through the epidermis were visible. Bright basal cells in some areas with no clear borders due to inflammation and dilated and coiled vessels in papillae were present. Intrapapillary space revealed inflammation with inflammatory cells forming clusters. A 5-year-old girl presented with a few small plaques located on the right hand, close to the thumb, and the right ankle's skin. Personal history was negative. Lesions have appeared around a month before, first on the hand, and after a few days on the skin of the right ankle. Dermoscopic examination showed a pinkish structureless area with dotted vessels (Figure 1D). In RCM of the epidermis, a typical honeycombed pattern with different sizes of keratinocytes in some areas was observed. In the lower part of the epidermis, there were tops of papillae with dilated vessels (Figure 1E). The RCM examination of the dermoepidermal junction showed bright basal cells with no clear borders. Intrapapillary dilated vessels (some of them coiled) and inflammatory cells spreading into the surrounding were observed (Figure 1F). The diagnosis of GA can be made in most cases clinically; however, for atypical presentations, additional tools such as dermoscopy or RCM may be helpful. Previous reports suggested that dermoscopy of GA reveals mainly unfocused vessels with variable morphology over a pinkish-reddish background. Focal or diffuse yellowish-orange areas were also noted. Lallas et al. described dermoscopic features of 47 lesions diagnosed as GA. In 40.4% of them, the vascular pattern was considered to be dotted, although some lesions were linear and arborizing. The color of the background was red and white, combined with yellow. In our study, lesions of both patients dermoscopically presented dotted vessels, although one of them had a pinkish background color, while the second was yellowishorange. Lacarrubba et al. described RCM pattern of inflammatory diseases; however, GA was not included in their analysis. They highlighted broadband intracellular spaces, inflammatory cells in the epidermis, and dilated vessels in the dermoepidermal junction as the most common RCM features of chronic dermatoses. In our patients suffering from GA, epidermis mostly revealed a regular honeycombed pattern. Keratinocytes of different sizes were observed in a small part of the epidermis. Inflammatory cells and debris of keratinocytes were present. Dermoepidermal junction revealed bright basal cells without sharp borders, probably due to the inflammatory process. Some vessels inside papillae were coiled. There were many inflammatory cells in the surrounding of papillae, which formed clusters in some areas. In conclusion, we describe here the RCM patterns of two cases of GA, which revealed features commonly seen in other inflammatory skin lesions. Whether RCM can add to the diagnostic accuracy of GA remains to be further determined by more extensive studies.