Challenges in the diagnosis of thrombotic thrombocytopenic purpura.

Introduction: Immune-mediated TTP (iTTP) is a rare condition without pathognomonic signs and symptoms. For this reason, the diagnosis of iTTP may be delayed or even missed, with potentially catastrophic consequences.

Areas Covered: The authors performed an extensive literature review on the diagnosis of iTTP and its challenges combined with their own experience in a referral center for patients with iTTP.

Expert Opinion: Although a definitive diagnosis of iTTP depends on the ADAMTS13 activity result, timely testing is rarely available at many centers to which patients present. If less complex tests were to become available, they would decrease the chances of late and/or missed diagnoses of iTTP throughout the world. While clinical scores to estimate the likelihood of iTTP exist, they are not well known, and can be misleading if used in the wrong context. Furthermore, the three scoring systems (PLASMIC, Bentley, and French) only moderately correlate with each other, which further complicates the landscape. The existence of these scores and how they should be used in practice is but one opportunity that can be seized through more robust programs to educate nonspecialist clinicians on how to recognize and treat patients with iTTP.