Diagnostik der Autoimmunthrombozytopenie

Zusammenfassung

Die Autoimmunthrombozytopenie (ITP) gehört mit einer Inzidenz von ca. 5,8–6,6 pro 100 000 Erwachsene zu den häufigsten Ursachen einer gestörten zellulären Gerinnung. Die ITP-Diagnose ist eine klassische Ausschlussdiagnose, da Unklarheit über die diagnostische Aussagekraft verschiedener, potenziell hilfreicher Biomarker besteht. In dieser Übersicht wird der Beitrag von Biomarkern der Autoimmunreaktion (Leptin, freie und gebundene Autoantikörper gegen Thrombozyten, Nachweis spezifischer B-Lymphozyten) und der Thrombopoese (Knochenmarkhistologie, Thrombopoietin, Glykocalicin, retikulierte Thrombozyten) zur Sicherung der ITP-Diagnose beleuchtet. Einige dieser Parameter sind mit hoher Wahrscheinlichkeit diagnostisch wertvoll. Prospektive Untersuchungen an gut charakterisierten Patientengruppen sind erforderlich, um Fortschritte in der Therapie der ITP durch zügige und sichere Diagnostik zu sichern.

Summary

Idiopathic thrombocytopenic purpura (ITP) has an incidence of 5.8–6.6 per 100 000 adults and represents a frequent cause of impaired cellular haemostasis in clinical practice. Its diagnosis is still one of exclusion, because the diagnostic value of proposed biological markers of the disease has been disputed.

The potential contribution of biomarkers both of the autoimmune reaction (leptin, free and cell-bound anti-platelet autoantibodies, specific B cells) and of thrombopoiesis (bone marrow histology, thrombopoietin, glycocalicin, reticulated platelets) to the diagnosis of ITP will be discussed. There is evidence that some of these biomarkers indeed could be useful in the diagnosis of ITP. To cope with the rapid progress in ITP therapy, prospective studies on well characterized cohorts are necessary to allow an efficient and definite diagnosis of this disease.

Schlüsselwörter

Autoimmunthrombozytopenie - Diagnostik - Biomarker

Keywords

Idiopathic thrombocytopenic purpura - diagnostic procedures - biomarker

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