Thrombotic thrombocytopenic purpura misdiagnosed as autoimmune cytopenia: Causes of diagnostic errors and consequence on outcome. Experience of the French thrombotic microangiopathies reference centre.
Fiche publication
Date publication
avril 2017
Journal
American journal of hematology
Auteurs
Membres identifiés du Cancéropôle Est :
Dr OJEDA-URIBE Mario
Tous les auteurs :
Grall M, Azoulay E, Galicier L, Provôt F, Wynckel A, Poullin P, Grange S, Halimi JM, Lautrette A, Delmas Y, Presne C, Hamidou M, Girault S, Pène F, Perez P, Kanouni T, Seguin A, Mousson C, Chauveau D, Ojeda-Uribe M, Barbay V, Veyradier A, Coppo P, Benhamou Y
Lien Pubmed
Résumé
Thrombotic thrombocytopenic purpura (TTP) has a devastating prognosis without adapted management. Sources of misdiagnosis need to be identified to avoid delayed treatment. We studied 84 patients with a final diagnosis of severe (<10%) acquired ADAMTS13 deficiency-associated TTP from our National database that included 423 patients, who had an initial misdiagnosis (20% of all TTP). Main diagnostic errors were attributed to autoimmune thrombocytopenia, associated (51%) or not (37%) with autoimmune hemolytic anemia. At admission, misdiagnosed patients were more frequently females (P = .034) with a history of autoimmune disorder (P = .017) and had organ involvement in 67% of cases; they had more frequently antinuclear antibodies (P = .035), a low/undetectable schistocyte count (P = .001), a less profound anemia (P = .008), and a positive direct antiglobulin test (DAT) (P = .008). In multivariate analysis, female gender (P = .022), hemoglobin level (P = .028), a positive DAT (P = .004), and a low schistocytes count on diagnosis (P < .001) were retained as risk factors of misdiagnosis. Platelet count recovery was significantly longer in the misdiagnosed group (P = .041) without consequence on mortality, exacerbation and relapse. However, patients in the misdiagnosed group had a less severe disease than those in the accurately diagnosed group, as evidenced by less organ involvement at TTP diagnosis (P = .006). TTP is frequently misdiagnosed with autoimmune cytopenias. A low schistocyte count and a positive DAT should not systematically rule out TTP, especially when associated with organ failure.
Mots clés
ADAMTS13 Protein, deficiency, Adult, Anemia, Hemolytic, Autoimmune, diagnosis, Antibodies, Antinuclear, analysis, Coombs Test, Diagnosis, Differential, Diagnostic Errors, Female, Hemoglobins, analysis, Humans, Male, Middle Aged, Prognosis, Purpura, Thrombocytopenic, Idiopathic, diagnosis, Purpura, Thrombotic Thrombocytopenic, diagnosis, Risk Factors, Sex Factors
Référence
Am. J. Hematol.. 2017 Apr;92(4):381-387