A coincidental occurrence of severe haemophilia A and Turner syndrome in a female person is extremely rare (less than 10 cases published). In such challenging cases, a multidisciplinary approach based on medicine of precision with full access to genetic and bio-molecular exploration is indispensable. The article presents an eight-year-old girl, with a family history of haemophilia, without significant disease signs (only post-dental extraction bleeding and a shorter stature). Discordantly, however, the investigations revealed a challenging condition: a genotype of 46,X,i(Xq), with an Isochromosome Xq responsible for the Turner syndrome and simultaneously, for the detrimental transformation, interfering with X chromosome inactivation, of an obligate hemophilia carrier into a severe hemophilia case-two distinct and provocative diseases.
Keywords: Isochromosome Xq; Turner syndrome; severe haemophilia A in female.