[Slowly progressive joint destruction in an older man as expression of hydroxyapatite disease. Case report and literature review].

This article reports the case of a 75-year-old male patient presenting with arthralgia of the large joints that had existed for 10 years. Clinically, bursitis of the right elbow joint was found. Laboratory tests showed elevated inflammatory markers and imaging revealed erosive joint destruction. A surgical bursectomy was performed. Histologically, hydroxyapatite crystals were detected in alizarin red S staining and a crystal arthropathy was diagnosed. The diagnostics are difficult since crystals can only be detected by electron microscopy or special staining methods.