[Bone disorders and complications of pediatric acute lymphoblastic leukemia : monocentric study and review of the literature].

Bone pain associated with bone marrow infiltration is often present at diagnosis of pediatric acute lymphoblastic leukemia (ALL). It sometimes signs the presence of pathological fracture, lytic lesions, arthritis, or osteitis associated to ALL that can delay the diagnosis. During treatment, bone complications (pain, osteopenia, fracture, avascular necrosis, ...) are also reported. In order to describe bone involvement (BI) of pediatric LLA, we reviewed the records of 104 patients followed in our unit. The overall incidence of BI was 67 %. At diagnosis, 50 % of patients had BI and in 19 %, the diagnosis of ALL was delayed. During and after treatment, respectively 28 % and 37 % of patients presented bone complications (pain, fractures, avascular necrosis, osteopenia). Patients with BI had a lower leukocytosis inferior to 10x109/l (p = 0.005) and an ALL of average risk (p = 0.019). 38 % of patients with BI during treatment were over 10 years old and 55 % were girls (vs. 21 % and 38 % in the entire cohort, respectively). Osteoporosis was more severe at diagnosis than during treatment, suggesting the presence of constitutional promoting factors. In our cohort, the majority of BI was resolved at the end of treatment with no long-term sequelae.