[H-H-H syndrome: a rare disease also relevant in anesthesiology]

We report on a 17-year-old boy with H-H-H-syndrome (hyperornithinaemia, hyperammonaemia, homocitrullinuresis), an inborn disorder of the urea cycle, who had to undergo osteo-synthesis of a fractured upper leg. Pathophysiological aspects of this rare syndrome as well as possible recommendations for the anaesthesiological management are discussed.