A Novel Homozygous GFI1B Mutation in Siblings With Thrombocytopenia and Bleeding Tendency.

Platelet type bleeding disorder 17 (OMIM #187900) is a type of "gray platelet syndrome" and occurs due to a mutation in the GFI1B gene on chromosome 9q34.13. Patients usually present with a history of easy bleeding tendencies, recurrent epistaxis or gum bleeding, and rarely with severe hemorrhage, and they may often be misdiagnosed. We herein report a novel autosomal recessive bleeding disorder in two sisters of the same family caused by a mutation in GFI1B, where both sisters, 13 and 8 years old, respectively presented with a history of recurrent episodes of epistaxis, firstly misdiagnosed and treated as ITP. Later, the final diagnosis was made with whole genome sequencing. The identification of GFI1B mutations in patients with thrombocytopenia and bleeding disorders highlights the importance of genetic testing in the diagnostic workup of these conditions. The cases reported here presented with mild to moderate thrombocytopenia and were initially misdiagnosed as ITP. Whole exome sequencing has proven to be a valuable tool in identifying mutations, as demonstrated in this case. This case report underscores the significance of evaluating for inherited platelet disorders in instances of recurrent bleeding.