Peter Mallal^1,2, Pierre Filion³, Aws Jasim³, Katherine J. Creeper^1,2

¹Department of Haematology, Sir Charles Gairdner Hospital, Nedlands, Western Australia

²Haematology Department, PathWest Laboratory Medicine, Nedlands, Western Australia

³Anatomical Pathology Department, PathWest Laboratory Medicine, Nedlands, Western Australia

 

Platelet storage disorders are a group of rare bleeding disorders characterised by a decrease in the number and contents of dense granules and/or α-granules¹. Disorders of dense granules are often inherited and frequently associated with other clinical manifestations including oculocutaneous albinism, immunodeficiency and occasionally pulmonary fibrosis².

 

We report a 56-year-old female with significant bleeding history (bleeding following dental extractions, bruising, menorrhagia and post-partum haemorrhages requiring transfusion), bilateral retinal detachment and a previous diagnosis of von-Willebrand’s disease. Both her mother and her maternal grandmother had a history of excessive bleeding, as well as deafness at a young age in maternal and paternal grandmothers. FBC, platelet morphology, coagulation profile and von Willebrand’s studies were normal. Light transmission platelet aggregometry showed negligible response to collagen and arachidonic acid and reduced response to ADP. Platelet electron microscopy showed markedly reduced numbers of dense granules and normal numbers of α-granules. Genetic testing for platelet storage disorders is currently pending.

 

Identification of reduced dense granules via electron microscopy remains a pivotal investigation in the diagnosis of platelet storage disorders. Genetic testing will identify a cause in as little as 9% of patients, consequently electron microscopy is critical for diagnosis³. 

 

This case has not previously been presented or published.

 

1.     Handin RI. Inherited platelet disorders. Hematology Am Soc Hematol Educ Program 2005: 396-402.

2.     Dupuis A, Bordet JC, Eckly A, Gachet C. Platelet δ-Storage Pool Disease: An Update. J Clin Med 2020; 9 (8).

3.     Brunet J, Badin M, Chong M et al. Bleeding risks for uncharacterized platelet function disorders. Res Pract Thromb Haemost 2020; 4 (5): 799-806.