Purpose: To define the epidemiology, clinical, biological and histological features of renal diseases in ankylosing spondylitis, ginving special attention to unusual forms.
Methods: We retrospectively reviewed the medical record of 28 cases with renal involvement among 210 cases of ankylosing spondylitis seen over a 27 year period who met the Amor criteria.
Results: Twenty-eight of 210 patients (13,3%) presented one or more signs of renal involvement: macroscopic hematuria (4 patients), microscopic hematuria (8 patients), proteinuria (15 patients), nephrotic syndrome (6 patients), decreased renal function (13 patients). Secondary renal amyloidosis and nephrolithiasis (8 patients) were the most common cause of renal involvement in ankylosing spondylitis followed by IgA nephropathy (3 patients).
Conclusion: The funding of renal abnormalities in 13,3% of our patients suggests that in this illness evidence of renal involvement should be actively investigated in ankylosing spondylitis.