Factors influencing outcome and incidence of late complications in children who underwent allogeneic hematopoietic stem cell transplantation for hemoglobinopathy.

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) remains the only potentially curative treatment for severe hemoglobinopathy (HGP). Late complications (LCs) are all events occurring beyond two years post-HSCT. We retrospectively analyzed prevalence, factors influencing occurrence, and prognosis of LCs post-HSCT for HGP.

PATIENTS AND METHODS

Between 2000 and 2011, 47 patients (21 males, 26 females; 43 with beta thalassemia major, four with sickle cell disease) who had survived more than two years post-HSCT for HGP were retrospectively reviewed. Mean age at HSCT was 7.7 years (1.1-32 years); mean follow-up was 7.1 years (2-11.6 years); 11 patients were splenectomized; mean ferritin level was 3022 ng/mL (350-10900); and seven patients underwent a second HSCT.

RESULTS

Endocrinological complications were observed with primary gonadal failure in 16/20 mature females and 4/11 mature males, in five patients with primary hypothyroidism and in four with insulin-dependent diabetes mellitus (DM). Skeletal complications were observed in 10 with secondary osteoporosis; 22 patients had elevated transaminase levels; two had hepatitis B reactivation. Neurological, cardiac and ocular manifestations were relatively rare. A higher incidence of LCs was observed in splenectomized than in nonsplenectomized patients: cGVHD -64% versus 13% (P = .003); endocrine abnormalities -91% versus 30.5%, (P = .001); elevated transaminase levels -73% versus 33% (P = .043); mortality -18% versus 2.7% (NS).

CONCLUSIONS

LCs post-HSCT for HGP are common and heterogeneous. Etiology is multifactorial with iron overload (IO), class, splenectomy, age, chronic GVHD, and corticosteroid (CS) treatment. Our data may help build follow-up guidelines to limit, detect, and treat any LCs and improve quality of life.