Dermoscopic Aspects of Cutaneous Adverse Drug Reactions

Abstract

Background: Little is known about the dermoscopic evaluation of cutaneous adverse drug reactions (CADRs).

Objectives: To evaluate the dermoscopic patterns of CADRs and identify those associated with severe cutaneous adverse reactions to drugs (SCARDs).

Patients and methods: Patients included in this study from May 2015 to April 2016 had presented with CADRs. CADR presentation and classification were based on standard criteria. SCARDs included Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), overlap SJS/TEN, drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP). The dermoscopic features of CADRs were described and compared according to the severity of the reactions.

Results: Sixty-nine patients were included. Sixteen patients (23.2%) presented SCARDs. The main dermoscopic findings in SJS, overlap SJS/TEN and TEN were black dots or necrotic areas (100%). Erosion [respectively, 4/6 (66.7%), 3/3 (100%) and 1/1 (100%)], necrotic borders [respectively, 4/6 (66.7%), 3/3 (100%) and 1/1, (100%)] and epidermal detachment [respectively, 5/6 (83.3%); 2/3 (66.7%) and 1/1 (100%)] were also common among these reactions. Erythema and purpuric dots were the main dermoscopic findings [respectively, 5/6 (83.3%) and 4/6 (66.7%)] in DRESS. In non-severe reactions, the most prevalent structures were erythema and purpura in exanthema [respectively, 31/33 (93.9%) and 24/33 (72.7%)] and erythema and vascular structures in urticarial reactions [respectively, 6/6 (100%) and 3/6 (50%)]. Black dots or necrotic areas, epidermal detachment, necrotic borders and erosion were highly associated with SCARDs (P < 0.001).

Conclusions: Dermoscopy improves clinical recognition of SCARDs.

Keywords: cutaneous adverse drug reactions; dermoscopic patterns; dermoscopy; drug eruptions.

Figure 1

Early manifestations of drug reactions in skin. (A) Clinical image of a patient with Stevens-Johnson syndrome on day 3 after symptom onset; (B) dermoscopic image showing slightly scattered black dots; and (C) histopathologic image showing a necrolytic epidermis and a necrotic keratinocytes. (D) Clinical image of a patient with an exanthematous reaction; (E) dermoscopic image showing only diffuse erythema; and (F) histopathologic image showing perivascular inflammatory infiltrate and ectatic vessels.

Figure 2

Clinical and dermoscopic images of a patient with Stevens-Johnson syndrome. On baseline evaluation (A) erythema and few tiny black dots are visualized on (B) dermoscopy. (C) After 3 days of follow-up, (D) black dots are diffusely distributed over the lesion.

Figure 3

(A, B, C) Stevens-Johnson syndrome cases showing distinct clinical features. Dermoscopy demonstrating distinct structures: (D and E) black dots; (E) necrotic borders and erosion; and (F) epidermal detachment. While dermoscopy may lead to early suspicion of the skin reactions in the first 2 patients (A and B), the third patient (C) is clearly diagnosed by his clinical scenario. Nevertheless, the dermoscopic structures are also more pronounced (F) (original magnification, ×10).

Figure 4

Clinical and dermoscopic images of non-severe cutaneous adverse drug reactions. (A) Clinical image demonstrating a patient with an exanthematous reaction and (D) showing erythema on dermoscopy. (B) Clinical image demonstrating a patient with urticaria and (E) showing erythema and linear vessels on dermoscopy. (C) Clinical image demonstrating a patient with cutaneous vasculitis and (F) showing purpuric dots (original magnification, ×10).