A 23-year-old female patient presented with spontaneous appearance of nail haemorrhages on both hands after a tracking holiday in Peru and Bolivia. At altitudes above 3000 meters, she initially developed painful splinter haemorrhages (figure 1), followed by subungual haematoma (figure 2) and eventually distal onycholysis at all fingernails on both hands (figure 3). Remarkably, her toenails were...