Congenital thrombotic thrombocytopenic purpura.

BACKGROUND: Congenital thrombotic thrombocytopenic purpura (TTP) is a rare, hereditary disorder. Clinically it presents as episodic microangiopathic haemolytic anaemia and thrombocytopenia with varying degrees of damage to internal organs. The condition may present in neonates, but can also present for the first time in adulthood. The prevalence of congenital TTP is particularly high in Norway, and it is therefore important for Norwegian doctors to be aware of the condition. In this article we review the main characteristics of the disease, including its diagnosis and management, and introduce potential new treatments for the future.

METHOD: The article is based on a literature search in PubMed as well as the authors’ own research and clinical experience.

RESULTS: There was great variation in the severity of congenital TTP: from neonatal mortality to disease-free intervals of several years. Episodes are generally precipitated by a trigger. Acute episodes are treated with plasma infusions, and approximately half of all patients experience frequent episodes and require prophylactic infusions to avoid organ damage. The risk of episodes is greatest in neonates, during pregnancy and in association with infections.

INTERPRETATION: There is little research-based evidence regarding long-term prognosis in congenital TTP. There is also a need for guidelines to help identify candidates for prophylactic treatment. An international patient registry would provide useful information and form the basis for better guidelines on the monitoring and treatment of these patients.