Detailed knowledge about the internal structure and remodeling of bone is fundamental for understanding bone disease of metabolic origin. The term renal osteodystrophy (ROD) is used generically to refer to a broad spectrum of skeletal disorders that appear as a consequence of chronic kidney disease (CKD) and from renal replacement therapy. Thus, ROD may be considered the paradigm of metabolic bone diseases, since the term encompasses, to varying degrees, all bone lesions of metabolic origin. Succinctly, ROD results from a variable combination of osteitis fibrosa and mineralization defects; it may present with normal, increased (osteosclerosis) or decreased (osteopenia, osteoporosis) bone mass.

This chapter describes metabolic bone lesions in general, and renal osteodystrophy in particular, with special emphasis on histologic interpretation. It also covers methods of study, and briefly, physiopathologic mechanisms.