Figure 1. Dependent acrocyanosis in POT patients. (a, b) The legs of the first case adolescent with POTS. The patient has significant red-blue discoloration of her legs extending up to the knees (a, b), compared to her arm (a), while standing. (c, d) The legs of the second case adolescent with POTS before (c) and after (d) staying in a standing position. The patient has significant red discoloration of her legs while standing.