Avascular Osteonecrosis and Accompanying Anemia, Leucocytosis, and Decreased Bone Mineral Density in Renal Transplant Recipients

Background: Avascular osteonecrosis (AVN) is a complication of renal transplantation. In this study, we present 12 cases of AVN associated with renal transplantation.

Methods: Renal transplant recipients (RTRs) with AVN (group I [GI]) were evaluated by using magnetic resonance imaging and blood urea nitrogen, creatinine, glucose, calcium, phosphorus, magnesium, alkaline phosphatase, parathyroid hormone, and urine analysis. We evaluated bone mineral density (BMD) of the femoral neck and lumbar vertebrae. All patients were treated with steroids, cyclosporine, or tacrolimus plus mycophenolate mofetil. Twenty-six RTRs (GII) without AVN were randomly selected as control subjects.

Results: The mean ages of GI and GII, were 33.81 ± 6.72 and 34.00 ± 7.65 years respectively (P > .05). The mean interval between transplantation and development of AVN was 12.08 ± 6.48 months. Although levels of blood urea nitrogen, creatinine, calcium, magnesium, and parathyroidhormone, as well as glucocorticoid doses in the first 12 months were similar in GI and GII, there were significant differences in serum alkaline phosphatase, hemoglobin levels, and white blood cell count between GI and GII (P < .05 for each). BMD T score <-1.5 was observed in 8/9 GI and 15/26 patients in GII. All of the patients with AVN except 1, were followed with conservative measures including calcium, magnesium, and vitamin D replacement therapies, bisphosphonate, and reduced or ceased glucocorticoid treatment. Although T scores of the femoral head were similar in GI and GII, the lumbar vertebral T score was significantly lower in GI than in GII (P < .052).

Conclusion: AVN developed within the first year after transplantation. Decreased lumbar vertebral BMD, which can be an indicator of glucocorticoid effect, accompanied AVN in nearly all patients. Despite the absence of renal dysfunction, increased bone destruction, anemia, and leucocytosis were coincidental or accompanying findings in our patients with AVN.