Factors Associated With Persistent Thrombocytopenia after Liver Transplantation

Background: Thrombocytopenia typically resolves with resolution of portal hypertension after liver transplantation (LT) but persists in some patients. Identifying risk factors associated with persistent post- LT thrombocytopenia may provide important information about its pathogenesis. Methods: Cirrhotic adults with platelet levels of <150,000 μ/L at the time of LT and followed at least 1 year were studied. A retrospective analysis of lab values, radiologic spleen index (SI), and donor data using nonparametric methods was performed to characterize patients having persistent thrombocytopenia, defined as persistently low platelet levels at 3 and 12 months after LT. Results: One hundred patients were studied: mean age 55 y (range 23-75 y); platelet count at LT 62,000/μL (range 14,000- 148,000/μL; mean total bilirubin 2.6 mg/dL; mean Mayo end-stage liver disease score 29; SI 1,476 (range 347-4,843 mL; normal 120-480 mL). Platelet count at 3 and 12 months after LT correlated with SI (r = -0.41 and -0.54; P < .001). Fifty-seven patients had persistent thrombocytopenia. Compared with patients whose platelet levels normalized by month 3 or 12, they had higher SI and lower platelet count before LT (P < .001). The SI and platelet levels at the time of LT were independent predictive factors for platelet levels at 3 and 12 months after LT (P < .001). Conclusions: High SI and low platelet count at the time of LT are associated with persistent thrombocytopenia after LT. They are also independent predictive factors of platelet levels at 3 and 12 months after LT. This suggests that patients may have persistent thrombocytopenia after LT owing to persistence of some degree of hypersplenism and incomplete resolution of splenomegaly.