Incidence, Risk Factors, and Outcomes of Primary Poor Graft Function after Allogeneic Hematopoietic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative therapy for both malignant and nonmalignant hematologic disorders. However, primary poor graft function (PGF) is a serious early complication of allo-HSCT that leads to a poor outcome. Little is known about the characteristics, incidence, and risk factors of primary PGF occurring after allo-HSCT. Here we performed a 1:4 ratio nested case-control study in 830 patients who underwent allo-HSCT between April 2013 and November 2018 at our center. Twenty-four patients (14 males and 10 females; average age, 35.79 years; range, 17 to 53 years) developed primary PGF. On univariate and multivariate analyses, a CD34⁺ cell dose <5 × 10⁶/kg (P = .003), a serum ferritin (SF) level >2000 ng/mL (P = .008), and splenomegaly (P = .039) were identified as 3 independent risk factors for primary PGF. After a median follow-up of 7.5 months (range, 1 to 48 months), only 5 patients (20.8%) survived. The survival rate of patients with primary PGF was significantly lower than that of patients with good graft function (GGF) (1-year overall survival, 25.0% versus 90.6%; P < .001). Cox regression analysis suggested that PGF and high SF level were strongly associated with rapid death in these patients. In conclusion, allo-HSCT recipients with a low CD34⁺ cell dose in their graft and exhibiting a high SF level and splenomegaly should be monitored for the development of primary PGF after allo-HSCT, and effective therapies need to be explored.