Detection of proximal tubular motile cilia in a patient with renal sarcoidosis associated with hypercalcemia.

In a normal human kidney, almost every cell type gives rise to a solitary primary cilium, an apical hair like nonmotile organelle that recently was linked to the pathogenesis of polycystic kidney disease. Motile cilia normally are not expressed by renal tubular cells in the mammalian kidney. Here, we report the unexpected detection of motile cilia arising from proximal tubular cells in a patient with sarcoidosis associated with hypercalcemia and renal impairment. The possible significance of this unusual finding is discussed.