Occult ischemic bone lesions in children with sickle cell disease: A study of prevalence

Introduction: Avascular necrosis (AVN) is a severe complication of sickle cell disease (SCD) and involves principally the femoral head. Few data exist about the prevalence of lesions in other segments. Methods: In this cross-sectional study, 42 children (20 males and 22 females) underwent a magnetic resonance imaging (MRI) of the spine, upper arms, and femurs. The primary outcome was to define the prevalence and locations of bone infarcts. Results: Forty-two patients completed the study; the total median age was 11.9 years (interquartile range = 9.5-13.9). Eleven patients (26.2%) were positive for altered bone findings for a total of 32 lesions. Most of the lesions were in the humerus 17 (53.1%), 11 (34.4%) in the femurs, and 4 (12.5%) in the vertebrae. The median number of vaso-occlusive crises (VOCs) was two and four for patients without and with bone lesions, respectively (p = .01). The annual rate of VOC is the best marker for the positive MRI (odds ratio = 82.6; p = .03), and it is correlated with the number of sites involved (p = .02). Conclusions: Our study highlights that the prevalence of skeletal lesions could be underestimated, and it provides the basis for clinical reasoning and tailored therapy in SCD children.