FGG and ornithine translocase deficiency: As for HHHS prevalence, it should be extremely rare, and only anecdotic information are available in the literature so far: (i) Aguadilla appears to be the most common mutation worldwide (with a total of 12 described index cases): (ii) FGG mutations associated with hepatic storage have been found in Turkey, Europe (Italy, France, Serbia), US, the Far East, the Caribbean, and Saudi Arabia (Table 1) [29,34].