Table of Content


Winter 2017, Vol. 25 No. 4

Hong Kong J. Dermatol. Venereol. (2017) 25, 202-203

Dermato-venereological Quiz

Dermato-venereological Quiz

ECY Chu 朱灼欣 and MT Ng 吳孟婷

A 89-year-old woman with a medical history of hypertension, diabetes mellitus, and atrial fibrillation presented with an erythematous rash on the right shin. Initially, the rash appeared as multiple nodular lesions over an area of 2 cm over the right shin (Figure 1). The extent of the lesions increased to cover an area of 8 x 14 cm over six months with the formation of multiple haemorrhagic blisters. Blood tests including liver function, renal function and complete blood picture were normal. Blood testing for anti-skin antibodies was negative. A skin biopsy was performed (Figures 2 & 3).

Figure 1 Multiple nodular lesions with haemorrhagic blisters over the right shin.

Figure 2 H&E stain with (a) 5x10 magnification & (b) 40x10 magnification.

Figure 3 Immunostain for S100.


  1. What is differential diagnosis?
  2. What is the histological finding?
  3. What is the diagnosis?
  4. What is the treatment?