Post Allogeneic Hematopoietic Cell Transplant Erythrocytosis in Aplastic Anemia: A Review of 208 Cases

Objectives: Post transplant erythrocytosis (PTE) is a known complication of renal transplantation, however post allogeneic hematopoietic cell transplant (alloHCT) erythrocytosis was reported for the first time by us in 2011. This paper is a follow up on our initial report. Materials and Methods: Out of 253 alloHCT performed for aplastic anemia, 208 patients with 18 months post-HCT follow up were included in this analysis. PTE was defined as hemoglobin level ≥16g/dL and ≥17g/dL for females and males respectively. Patients with PTE were further investigated to rule out secondary causes. Results: Fourteen patients developed post-HCT erythrocytosis. All were male with median age of 21 years (range 16-28.5). Median disease duration prior to transplant was 7 months (range 1.5-16). Median time from HCT to development of erythrocytosis was 33 months (range 18-51). Maximum Hb level attained was 19.9 g/dL. Median erythropoietin level was 7.98mU/mL (range 2.6-13.65). None of these patients tested positive for JAK-2 V617F mutation. Four patients developed hepatitis post HCT, preceding PTE. Univariate analysis revealed significant association with male gender (OR 8.4; p=0.004), age >15 years at transplant (OR 4.2; p=0.04), pre-transplant high number of RCC (median 72 units vs 31 in non-PTE group; p<0.001) and platelets transfusions (median 249 events vs 66; p=0.001), ciclosporin-induced hypertension (OR 5.9; p=0.015) and viral hepatitis (OR 6.5; p=0.01). Except for number of platelet transfusions (p=0.015) none of the factors noted above had any significant correlation on multivariate analysis. Most patients required 2-3 phlebotomies per year. No thrombo-embolic event was observed.