Successful Unrelated Peripheral Blood Stem Cell Transplantation from Unrelated Donor for a Concomitant Paroxysmal Nocturnal Hemoglobinuria and Heterozygous α-Thalassemia Patient

Background: Paroxysmal nocturnal haemoglobinuria (PNH) is a rare acquired clonal hematopoietic stem cell (HSC) disorder that manifests as hemolytic anemia, venous thrombosis, and deficient hematopoiesis. PNH concomitant with inherited hemolytic anemia has been rarely reported. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is considered the only curative therapeutic measure. Here, We present our first allo-HSCT form unrelated donor for a 23-year-old patient with PNH and heterozygous α-thalassemia.

Case report: Flow cytometry of the patient's peripheral blood demonstrated that 7.9% and 11.9% of the erythrocytes were CD59 and CD55 deficient, respectively. Thalassemia gene analysis revealed heterozygous α-thalassemia. The patient was diagnosed with PNH and heterozygous α-thalassemia, and became transfusion dependent 1 year later and was admitted to our hospital in March 2011. Conditioning was consisited of Cyclophosphamide (d-10 to d-9), Fludarabine(d-8 to d-4), Busulfan (d-7 to d-5), Thiotepa (d-4) and ATG-F (d-3 to d-1). Stem cell source was peripheral blood stem cells (PBSC) harvested on the 16th October 2011 from a HLA-matched (8/8) unrelated donor. The infused mononuclear cell (MNC) and CD34⁺cell does were 8×0⁸/kg and 1.38×10⁶/kg body weight of the recipient, respecitively.The time to platelets engraftment and leukocyte engraftment was 21 and 25 days,respecitively.The patient did not accoured acute graft versus host disease (aGVHD). Out-patient were followed up for 2 years, the patient's liver and kidney function, urine which showed normal, as well as reviewed the implant remains for independent plantentry.

Conclusions: The present case suggests that allo-HSCT can be used to cure patient with PNH and heterozygous α-thalassemia. Allo-HCT from unrelated donors is a new and potentially curative option for patients with PNH and inherited hemolytic anemia.