Skin Research and Technology | 2019
The role of in vivo reflectance confocal microscopy in assessing the stability of vitiligo vulgaris prior to cellular grafting
Abstract
Noncultured cellular grafting (NCG) on stable vitiligo is an essential requirement for successful repigmentation.1 Vitiligo is considered stable, when there is no progression of old lesions or development of new lesions in the past 6 months. This is determined clinically, through vitiligo disease activity (VIDA) score and Wood’s lamp examination. However, this is very subjective. Although test punch grafting has been shown to aid in selecting appropriate patients for surgical intervention, it is not an absolute indication for successful surgical repigmentation. There have been instances of failed surgical attempts in patients with positive test grafting and vice versa. This suggests that the stability may be sitedependent.2 Recently, the noninvasive realtime in vivo reflectance confocal microscopy (RCM) imaging has been reported to be a useful tool to stage the activity of vitiligo.3,4 RCM allows noninvasive imaging of the epidermis and the upper dermis at a nearhistological resolution. This technique has been used for the evaluation of several inflammatory, neoplastic and melanocytic skin conditions and may constitute an excellent alternative to invasive biopsy collection in the diagnosis of several skin disorders. In this open observational study, we aim to evaluate the role of RCM in assessing the stability of vitiligo vulgaris prior to NCG and to correlate the observed RCM features with the success of NCG. A total of 28 patients with clinically stable vitiligo vulgaris (defined by no progression of old lesions or development of new lesions in the past 6 months) scheduled for test punch grafting or NCG were recruited. Vitiligo disease activity scoring and RCM were performed on the vitiligo lesion prior to the procedure (Table 1). The result of the procedure was assessed after 6 months. A successful grafting was defined as achievement of >75% repigmentation, and failure of grafting was defined as achievement of <75% repigmentation. RCM imaging was performed at the centre and the border of the vitiligo lesion. The assessment of RCM findings was done by two dermatologists using the scoring index proposed by Li et al4 to indicate the stage of vitiligo. This was the scoring index used: (a) Pigmentation status in the lesional skin: +1 score denoted the existence of remaining pigment and −1 score denoted complete loss of pigment; (b) Status of the border of vitiligo lesion: +1 score denoted indistinct border and −1 score denoted clear border; (c) Inflammatory cell infiltration: +1 score if inflammatory cell infiltration was detected at the edge of the lesion; and (d) Melanocyte regeneration: −1 score if dendritic melanocytes appeared in the vitiligo lesion. Total score <1 represented stable stage; ≥1 represented active stage; ≥2 represented rapid active stage (Figures 1 and 2). Five patients were lost to followup. Out of the 23 patients who had completed the study, 21 patients had NCG and two had test punch grafting. Nineteen patients had successful grafting. When comparing the success of grafting with the RCM score, 14 out of 19 patients had stable RCM staging (sensitivity: 73.7%; positive predictive value: 87.5%). Four patients had unsuccessful grafting. Two out of the four patients had an active RCM staging (specificity: 50%;