title: A diagnostic approach that may help to discriminate inherited thrombocytopenia from chronic immune thrombocytopenia in adult patients.
abstract: Inherited thrombocytopenia (IT) is a heterogeneous group of rare diseases that are often confused with immune thrombocytopenia (ITP). The objective of this study was to supply clinicobiological elements that allow a distinction to be drawn between IT and chronic ITP. We then compared 23 adult patients with IT and 9 patients with chronic ITP. Our study revealed six discriminating criteria: (i) an age of discovery <34 years: positive predictive value (PPV) = 88.2% [63.6; 98.5], (ii) a family history of thrombocytopenia: PPV = 100.0% [82.4; 100.0], (iii) a personal history of bleeding: PPV = 100% [76.8; 100.0], (iv) a mean platelet volume >11 fL: PPV = 93.3% [68.1; 99.8], (v) an excess of giant platelets on blood smear: 100.0% [76.8; 100.0], and (vi) a percentage >44% of platelets with a surface area >4 µm(2) in electron microscopy: PPV = 83.3% [58.6; 96.4]. If at least three of these criteria were combined, it was possible to distinguish IT from chronic ITP with 91.3% [72.0; 98.9] sensitivity and PPV = 100.0% [66.4; 100.0] specificity. The secondary objective of this study was to assess the prevalence of potential IT diagnosis in patients with chronic thrombocytopenia of uncertain origin. Applying our diagnostic approach to a series of 20 cases allowed us to estimate that 40% of them could be suffering from IT. Finally, our diagnostic approach may help to correctly distinguish IT from chronic ITP, particularly in the context of macrothrombocytopenia.
authors.affiliation: a Laboratory of Haematology , Bordeaux University Hospital Centre , Pessac , France.|b Reference Centre for Platelet Disorders , Bordeaux University Hospital Centre , Pessac , France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Fiore
authors.affiliation: b Reference Centre for Platelet Disorders , Bordeaux University Hospital Centre , Pessac , France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Pillois
authors.affiliation: c Clinical Investigation Centre , Bordeaux University Hospital Centre , Bordeaux , France.
authors.forename: Simon
authors.initials: S
authors.lastname: Lorrain
authors.affiliation: c Clinical Investigation Centre , Bordeaux University Hospital Centre , Bordeaux , France.
authors.forename: Marie-Agnès
authors.initials: MA
authors.lastname: Bernard
authors.affiliation: c Clinical Investigation Centre , Bordeaux University Hospital Centre , Bordeaux , France.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Moore
authors.affiliation: b Reference Centre for Platelet Disorders , Bordeaux University Hospital Centre , Pessac , France.|d Laboratory of Haematology , Toulouse University Hospital Centre , Toulouse , France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Sié
authors.affiliation: e Internal Medicine Department , Bordeaux University Hospital Centre , Pessac , France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Viallard
authors.affiliation: b Reference Centre for Platelet Disorders , Bordeaux University Hospital Centre , Pessac , France.|f Rythmology and Cardiac Modeling Institute (LIRYC) , Xavier Arnozan Hospital Centre , Pessac , France.
authors.forename: Paquita
authors.initials: P
authors.lastname: Nurden
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000276:immunology; D001792:Blood Platelets / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure; D015897:Comorbidity; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D005820:Genetic Testing; D006470:Hemorrhage / Q000209:etiology; D006801:Humans; D008297:Male; D063847:Mean Platelet Volume; D008875:Middle Aged; D009154:Mutation; D010976:Platelet Count; D010979:Platelet Function Tests; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000276:immunology; D012680:Sensitivity and Specificity; D013921:Thrombocytopenia / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000209:etiology*; D055815:Young Adult
chemical_list: D001323:Autoantibodies
keywords: Giant platelets; immune thrombocytopenia; inherited thrombocytopenia; mean platelet volume; platelet electron microscopy