[Brown tumors in chronic hemodialysis patients]

Brown tumors are rare and severe manifestations of secondary hyperparathyroidism. We propose in this study: to define and illustrate brown tumors observed in our hemodialysis center; to show the frequency for 20 years in our center; to identify risk factors compared to the rest of dialysis patients; and finally to offer improved support for reducing the incidence.

We conducted a retrospective and descriptive study, over a period of 20 years (1993-2013), including 311 cumulative patients which are chronic hemodialysis in our unit.

Twenty-one patients had brown tumors (6.75%). The average age was 36.1 years and the sex ratio M/F is of 0.6. The average time between the start of hemodialysis and the diagnosis of brown tumor was 87.6 months. Clinical symptoms were dominated by bone pain, found in 76.1% of cases. The most frequent locations were costal (28.5% of cases), while spinal involvement was less frequent (4.76% of cases). The location was multifocal in 57.1% of cases. The mean serum calcium was of 2.08 mmol/L, the serum phosphate of 2.25 mmol/L, alkaline phosphatase of 1709 IU/L and the average value of parathyroid hormone of 1934 pg/mL. Radiography was the key of diagnostic. Resonance magnetic imaging and computed tomography had an interest in the exploration of spinal locations and maxillo-mandibular locations. All patients underwent parathyroidectomy and it was total in one patient. Tumorectomy was necessary in three patients (14.2% of cases). The outcome was favorable in 85.7% of cases.

Our work relates one of the most important series published of brown tumors and is characterized by the multifocal character of these tumors.