Dermoscopy could be useful in differentiating sarcoidosis from necrobiotic granulomas even after treatment with systemic steroids

Abstract

Background:Diagnosing cutaneous sarcoidosis and necrobiotic granulomas is challenging.Objective:Assessing the value of dermoscopy in differentiating cutaneous sarcoidosis from necrobiotic granulomas and evaluating whether their dermoscopic features will be altered after treatment.Methods:Nineteen cutaneous sarcoidosis and 11 necrobiotic granuloma patients (2 necrobiosis lipoidica, 4 granuloma annulare and 5 rheumatoid nodule) were included in this study. The diagnosis was confirmed by skin biopsy. The lesions were examined using non-contact polarized dermoscope (Dermlite 2 HR-Pro; 3Gen, San Juan Capistrano, CA).Results:Ten out of 19 cutaneous sarcoidosis patients and 7/11 necrobiotic cases group were receiving treatments (topical, intralesional or systemic steroids ± chloroquine) but still have cutaneous lesions. Treatment duration in the sarcoidosis group ranged from 2 months to 10 years (median 3 years) and in the necrobiotic cases group ranged from 3 months to 16 years (median 2 years). Pink homogenous background, translucent orange areas, white scar-like depigmentation and fine white scales were significantly associated with the cutaneous sarcoidosis compared to necrobiotic cases group. On the other hand mixed pink, white and yellowish background was significantly associated with the necrobiotic cases group. No significant difference in the dermoscopic findings was detected between treated and non-treated patients.Conclusion:Some dermoscopic findings are shared between the cutaneous sarcoidosis group and the necrobiotic cases group, yet dermoscopy could be a useful aid in differentiating them even after treatment.

Dermoscopy of Granuloma Annulare: A Clinical and Histological Correlation Study

“…Such a variability is easily explained by the fact that the visibility of the vessels, especially if they are faint (as in GA), is highly affected by the type of dermoscopic techniques employed (better visualization with polarized devices) and the amount of pressure applied to the skin during the examination [3,7] . Regarding whitish areas, our results are in line with what was observed in other analyses, in which they turned out to be the most frequent non-vascular feature, with a prevalence ranging from 63.8 to 100.0% [20,21,24] . Such a finding is probably the result of the common occurrence of collagen degeneration/mucin deposition in GA, which may be responsible for whitish discolouration on dermoscopic examination [3,7,23] .…”

“…Moving to the usefulness of dermoscopy in the differential diagnosis of GA, several studies have emphasized that such a technique may be helpful to distinguish this dermatosis from both sarcoidosis and necrobiosis lipoidica, based on the assumption that yellowish/orangish colour and focussed vessels, typical of the latter conditions, are rarely seen in GA [20,21,24] . However, while a similar rule could be still considered for lesions showing an interstitial histological pattern, our analysis revealed that classic GA having a palisading granuloma histology may commonly display yellowish/orangish structureless areas, so only a meticulous assessment of vascular structures might orientate towards a correct diagnosis, with blurry vessels being indicative of GA and focused vessels being characteristic of sarcoidosis (linear or branching vessels) and necrobiosis lipoidica (commashaped, network-shaped/hairpin-like, or elongated, branching and focussed serpentine vessels) [7] .…”

“…Indeed, albeit dermoscopic examination of this dermatosis has been reported to show heterogeneous findings, the use of such a technique may come in handy to support the distinction from its main differential diagnoses as they typically show a different appearance [20][21][22][23][24] . However, none of the dermoscopic analyses carried out on GA so far has taken into account the variability of dermoscopic findings according to clinical features or histological subtype.…”

“…Over the last few years, several studies have shown that dermoscopy may be a useful tool to assist the non-invasive diagnosis of various inflammatory skin diseases [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] , including classic GA [20][21][22][23][24] . Indeed, albeit dermoscopic examination of this dermatosis has been reported to show heterogeneous findings, the use of such a technique may come in handy to support the distinction from its main differential diagnoses as they typically show a different appearance [20][21][22][23][24] .…”

Sarcoidosis- A Rare Disease Diagnosis by Cutaneous Manifestation, Clinical and Histopathological Correlation

“…Routine follow-up is going on as relapse rate is very high in sarcoidosis. 7,8,9 Depending on the available data, the relapse rate of sarcoidosis varies from 13%-75%. In our study, no relapse case reported till date in fortunately.…”