Flow chart of the diagnostic algorithm for PCD, used in our center. Functional evaluation (CBF and coordination of ciliary beating) was performed on the fresh biopsy, provided that cilia were present. If sufficient material was obtained, a part of the biopsy is prepared for TEM, the rest is brought in a cell culture system. After ciliogenesis in culture, all the samples are evaluated for functional and structural abnormalities. The diagnosis of PCD is made when coordination after ciliogenesis in culture (marked in grey) is abnormal. Genetic analysis is not performed routinely, but is performed preferentially in patients with normal ultrastructure.