Serum thrombopoietin levels and its relationship with thrombocytopenia in patients with cirrhosis

Background: Patients with cirrhosis usually have thrombocytopenia in discrete levels. The mechanism of thrombocytopenia is thought as splenic sequestration and destruction of platelets, impaired bone marrow generation and diminished hepatic thrombopoietin synthesis.

Objectives: The aim of this study was to evaluate serum thrombopoietin levels and its relationship with thrombocytopenia at patients with cirrhosis.

Patients and methods: Ninety-two cirrhotic patients and 45 healthy controls without history or findings of pathologies that can effect thrombopoietin levels were enrolled by simple random sampling to patient and control groups of this case control study performed at Eskisehir-Turkey. Thrombopoietin was measured in serum samples with a solid phase enzyme-linked immune absorbent assay. Additionally, spleen size and volume index were determined.

Results: Platelet counts were lower in patients with cirrhosis (97000 ± 8000/mm(3)) than in healthy subjects (240000 ± 51000/mm(3), P < 0.001). Significant difference was determined for platelet counts among child A, B and C stages (Child A vs. Child B P < 0.05 Child A vs. Child C P < 0.001-Child B vs. Child C P < 0.05). Serum TPO concentration was higher (69 ± 12 pg/mL) in cirrhotic group than healthy controls (49 ± 9 pg/ml) (P < 0.05). No significant difference in TPO levels were found among the Child A, B and C stages (64 ± 11 pg/mL, 75 ± 13 pg/mL and 68 ± 10 pg/mL, respectively). Spleen size and SVI was significantly higher in the cirrhotic patients than healthy controls (148 ± 14 mm vs. 98 ± 11 mm, P < 0.001-9167 ± 287 cm(2) vs. 4118 ± 123 cm(2)). Significant difference was determined for spleen size and spleen index among child A, B and C stages (Child A vs. Child B P < 0.05 Child A vs. Child C P < 0.001-Child B vs. Child C P < 0.05). TPO levels were significantly different between cirrhotic patients with platelet levels below 50.000/mm(3) (n = 16, plt-count: 41000 ± 8300/mm(3), TPO levels: 73 ± 7 pg/mL) and above 50.000/mm(3) (n = 76, plt-count: 105000 ± 9500/mm(3), TPO levels: 65 ± 10 pg/mL) (P < 0.01). In correlation analysis, there was a strong negative correlation between platelet count-spleen size (P < 0.001, r = -0.74) and platelet count-serum TPO levels (P < 0.001, r = -0.71).

Conclusions: Our results suggest that liver cirrhosis does not cause impaired thrombopoietin production even in the late stage of disease. Thrombopoietin has no contribution for the occurrence of thrombocytopenia in cirrhosis; splenic sequestration seems to be the main factor.