De novo thrombotic microangiopathy after non-renal solid organ transplantation

Abstract

Thrombotic microangiopathy (TMA) is a rare but serious complication of organ transplantation. This article presents the first literature review on TMA following non-renal solid organ transplantation (SOT). Ischemia-reperfusion, immunosuppressive drugs, acute interfering disease and a relative deficiency of the von Willebrand factor (vWF) cleaving protease (ADAMTS13) appear to play a major role in its pathogenesis. De novo TMA occurs in 4.0% of liver and 2.3% of lung transplant recipients, whereas the incidence remains unknown after intestinal transplantation. The median time of onset is 2, 37 and 8 weeks after liver, lung and intestinal transplantations respectively, with a three month survival of about 70%. In heart transplantation TMA is rare, occurrence is late and prognosis is poor. In TMA early after liver transplantation an elevated vWF/ADAMTS13 ratio may show diagnostic value. Early withdrawal of calcineurin inhibitors (CNI) proves to be lifesaving. Conversion to another CNI and rechallenge after resolution are generally safe, except after heart transplantation. The value of plasma exchange therapy remains controversial.

Keywords: ADAMTS13; Calcineurin inhibitor; Heart transplantation; Intestinal transplantation; Liver transplantation; Lung transplantation; Organ transplantation; Plasma exchange; Thrombotic microangiopathy; mTOR inhibitor; von Willebrand Factor.