Abstract Number: PB0874
Meeting: ISTH 2021 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » Inherited Thrombocytopenias
Background: Inherited platelet disorders result from functional abnormalities that cause failure of platelet adhesion, activation or aggregation. They are rare but clinically important because they are associated with hemorrhagic complications; furthermore their final diagnosis is often difficult to establish. Specifically, the Gray Platelet Syndrome (GPS) is characterized by defective production of alpha granules in platelets and it may be caused by different mutations in genes like NBEAL2 and, rarely, GFI1B. Nowadays, the existence of new molecular diagnostic techniques such as next generation sequencing (NGS) has allowed us to identify a new mutation in the GFI1B by whole exome sequencing (WES).
Aims: Our objective is to revise the diagnosis of a patient with long-standing constitutional thrombopenia who has been refractory to traditional treatments and was finally diagnosed with a GPS. We also revised his available family members in order to detect GPS features in them.
Methods: We revised patient´s medical and family history (Figure 1), including initial diagnosis (morphological assessment, flow cytometry analysis, bleeding score), treatments and it was performed a WES by NGS with the finding of an autosomal dominant mutation in GFI1B (Heterozygous mutation in exon 6: c.737G>A, p.Arg246Gln).Figure 1: Family Tree
Results: Since the patient had been initially labelled as inmune thrombocytopenia, there was no response to inmunosupresive treatments (prednisone, cyclophosphamide, vincristine, immunoglobulins and splenectomy), which is concordant with the present diagnosis of GPS. There is also no progression to myelofibrosis or platelet sensitization after the transfusions received. We found that not all direct relatives had clinical involvement, but there were morphological features of the disease (Figure 2).Figure 2: Characteristics of Autosomal Dominant Gray Platelet Syndrome
Conclusions: New molecular diagnostic techniques has allowed us to make a correct diagnosis. An early identification of the causing mutation could have avoided potentially damaging treatments as splenectomy.
Extension of the family study could shed light on the genotype-phenotype correlation, and confirm a possible incomplete penetrance profile.
To cite this abstract in AMA style:
Peleteiro Raíndo A, Mellid Fernández E, De Andrés y Jacob A, Abuin A, Díaz Arias JÁ, Fontanes Trabazo E, Vilariño López MD, Mosquera Orgueira A, Alonso Vence N, Bao Pérez L, Cadahía Fernández P, Ferreiro Ferro R, Melero Valentín P, Cid López M, Vidal Pérez F, Corrales Insa I, Bello López JL. Evolution over 50 Years of a Patient with Undiagnosed Gray Platelet Syndrome [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/evolution-over-50-years-of-a-patient-with-undiagnosed-gray-platelet-syndrome/. Accessed June 25, 2022.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/evolution-over-50-years-of-a-patient-with-undiagnosed-gray-platelet-syndrome/