High prevalence of infectious events in thrombotic thrombocytopenic purpura and genetic relationship with toll‐like receptor 9 polymorphisms: experience of the French Thrombotic Microangiopathies Reference Center. Issue 2 (27th May 2013)

• Record Type: Journal Article
• Authors: Morgand, Marjolaine; Buffet, Marc; Busson, Marc; Loiseau, Pascale; Malot, Sandrine; Amokrane, Kahina; Fortier, Catherine; London, Jonathan; Bonmarchand, Guy; Wynckel, Alain; Provôt, François; Poullin, Pascale; Vanhille, Philippe; Presne, Claire; Bordessoule, Dominique; Girault, Stéphane; Delmas, Yahsou; Hamidou, Mohamed; Mousson, Christiane; Vigneau, Cécile; Lautrette, Alexandre; Pourrat, Jacques; Galicier, Lionel; Azoulay, Elie; Pène, Frédéric; Mira, Jean‐Paul; Rondeau, Eric; Ojeda‐Uribe, Mario; Charron, Dominique; Maury, Eric; Guidet, Bertrand; Veyradier, Agnès; Tamouza, Ryad; Coppo, Paul;
• Is Part Of: Transfusion. Volume 54:Issue 2(2014)
• Page Start: 389
• Page End: 397
• Publication Date: 2013-05-27
• Subjects: Hematology -- Periodicals; Blood -- Transfusion -- Periodicals; Blood Group Antigens -- Periodicals; Blood Preservation -- Periodicals; Blood Transfusion -- Periodicals; 615
• DOI: 10.1111/trf.12263
• Languages: English
• ISSNs: 0041-1132

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="trf12263-sec-0001" sec-type="section"> <title>Background</title> <p>Infectious events have been reported as major environmental triggers of thrombotic thrombocytopenic purpura (TTP). We detail here the potential association between infections and TTP.</p> </sec> <sec id="trf12263-sec-0002" sec-type="section"> <title>Study Design and Methods</title> <p>We recruited randomly and prospectively a cohort of 280 consecutive TTP patients during a 9‐year period. Features of infection were systematically recorded.</p> </sec> <sec id="trf12263-sec-0003" sec-type="section"> <title>Results</title> <p>Features consistent with an infectious event were observed in 114 patients (41%) at time of TTP diagnosis. Infectious agents were documented in 34 cases and were mainly Gram‐negative bacilli. At time of diagnosis infected patients more frequently had fever (p < 0.001). Infections at diagnosis did not impact prognosis and outcome. Thirty‐six percent of patients experienced an infectious event during hospitalization, which resulted in more exacerbation of TTP (p = 0.02). Infections were not overrepresented during treatment in patients who received steroids and/or rituximab. Further genetic analysis of toll‐like receptor (TLR)‐9 functionally relevant polymorphisms revealed that TLR‐9 +2848 G and TLR‐9 +1174 A genotypes were more frequent in TTP patients than in controls (p = 0.04 and p = 0.026, respectively) and more particularly in patients negative for the Class II human leukocyte antigen system susceptibility allele DRB1*11 (p = 0.001 and p = 0.002, respectively). Haplotypes estimation showed that 1174A‐2848G haplotype was significantly more frequent in TTP (p = 0.004), suggesting a primary role for this haplotype variation in conferring a predisposition for acquired TTP.</p> </sec> <sec id="trf12263-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Infections should be considered as an aggravating factor during the course of TTP. Particular polymorphisms in TLR‐9 gene may represent risk factors for TTP.</p> </sec> </abstract>