Granulomatous skin disease
Granulomatous skin diseases In dermoscopy, the presence of orange-yellowish globules or areas and linear vessels are highly suggestive of dermal granulomas and therefore easily allows the diagnosis of granulomatous skin diseases. However, their differential diagnosis remains challenging due to identical dermoscopic presentation produced by several causes. Notably, the plaque form of cutaneous sarcoidosis may resemble necrobiosis lipoidica.[1][2] The longer and more branching telangiectasias of necrobiosis lipoidica, caused by atrophic changes not present in cutaneous sarcoidosis, were reported to be an important feature for discrimination from other granulomatous diseases.[3][4]
Sarcoidosis and lupus vulgaris
In sarcoidosis [1] and lupus vulgaris[5], orange-yellowish translucent globular-like or structureless areas in combination with linear vessels have been described, which are suggested to correspond to the underlying granulomas.
Cutaneous leishmaniasis
In cutaneous leishmaniasis, dermoscopy reveals generalized erythema, yellow tears (follicular plugs), hyperkeratosis and central erosion/ulceration. The characteristic translucent orange-yellowish color of sarcoidosis may additionally be present.[6]
Granuloma annulare
Granuloma anulare may reveal a high variability of dermoscopic findings. Vessels may be dotted, short linear or linear arborizing, while background color displays various combinations of red, white and yellow. In certain cases, pigmented structures may be detected. The observation that granuloma anulare rarely exhibits features of other granulomatous skin diseases, such as necrobiosis lipoidica or sarcoidosis, might help clinicians rule out the latter conditions.[4]
Necrobiosis lipoidica
Necrobiosis lipoidica exhibits a characteristic and repetitive pattern, typified by a prominent network of linear arborizing vessels and a yellow background color. The prominent vascular network of necrobiosis lipoidica represent the most valuable feature for differential diagnosis from other granulomatous diseases.[7][3] This typical vascular morphology should be differentiated from the classical ‘arborizing' vessels of nodular-cystic basal cell carcinoma. Classical arborizing vessels usually reveal ramifications into finest capillaries, while vessels in necrobiosis lipoidica exhibit only few diameter variegations and reveal multiple anastomosing ramifications.[4] Ulcerations and yellow crusts represent the most common additional features.[7]
- ↑ 1.0 1.1 Pellicano et al.: Dermoscopy of cutaneous sarcoidosis. Dermatology (Basel) 2010;221:51-4. PMID: 20375489. DOI.
- ↑ Bakos et al.: Dermatoscopy of early-onset necrobiosis lipoidica. J. Am. Acad. Dermatol. 2012;66:e143-4. PMID: 22421129. DOI.
- ↑ 3.0 3.1 Balestri et al.: Dermoscopic subpatterns of granulomatous skin diseases. J. Am. Acad. Dermatol. 2013;69:e217-8. PMID: 24124838. DOI.
- ↑ 4.0 4.1 4.2 Pellicano et al.: Dermoscopy of necrobiosis lipoidica and granuloma annulare. Dermatology (Basel) 2013;226:319-23. PMID: 23797090. DOI.
- ↑ Brasiello et al.: Lupus vulgaris: a new look at an old symptom--the lupoma observed with dermoscopy. Dermatology (Basel) 2009;218:172-4. PMID: 19060460. DOI.
- ↑ Llambrich et al.: Dermoscopy of cutaneous leishmaniasis. Br. J. Dermatol. 2009;160:756-61. PMID: 19120331. DOI.
- ↑ 7.0 7.1 Bakos et al.: Dermatoscopy of early-onset necrobiosis lipoidica. J. Am. Acad. Dermatol. 2012;66:e143-4. PMID: 22421129. DOI.
