1.What is immobilized cilia syndrome? Immobile cilia syndrome is the common name for primary ciliary dyskinesia (PCD), an autosomal recessive genetic disorder in which defects in cilia structure lead to impaired activity causing reduced ciliary clearance and other dysfunctions. 2.What are the clinical manifestations of primary ciliary dyskinesia? The main manifestations are chronic sinusitis, secretory otitis media, tracheobronchitis, bronchiectasis, visceral transposition and male infertility and female infertility, which occur from childhood and recurrently. Among them, the triad of sinusitis/nasal polyps, bronchiectasis and visceral transposition, called Kartagener’s syndrome, accounts for 50% of the total number of patients with immobile cilia syndrome. 3.What is the normal structure of cilia? The ultrastructure of cilia can be divided into two main categories: motile cilia and primary cilia. There are two central microtubules in the center of motile cilia, surrounded by 9 peripheral microtubules composed of secondary fibers A and B, with motile arms, linking loops and spokes, forming the so-called “9+2 type” (Figure); primary cilia have no central microtubules and no peripheral structures such as motile arms, linking loops and spokes, but only 9 peripheral microtubules, forming the so-called “9+2 type” (Figure); primary cilia have no central microtubules and no peripheral structures such as motile arms, linking loops and spokes. There are only 9 peripheral microtubules, forming the so-called “9+0 type”. 4.What are the common abnormalities of cilia structure? The main ultrastructural abnormalities of cilia include partial or complete absence of ciliary power protein arm, defective radial spokes, absence of central sheath, etc. 5.The role and location of power cilia and primary cilia? Power cilia are located in the epithelium of respiratory tract, ventricular ventricle epithelium, oviduct epithelium and spermatozoa, etc. Their main function is to promote fluid flow through their rhythmic movement. Primary cilia are located in the optic cone, optic rod cells, vestibular hair cells, olfactory epithelium, etc. Their main function is to sense and perceive changes in the extracellular environment. 6.What is the pattern of symptoms in patients with primary ciliary dyskinesia? The onset of PCD is early, mostly before the age of 15, and there is a regularity of symptoms in patients of different ages. In children, the main symptoms are chronic or recurrent otitis media; in youth, chronic sinusitis is common; in adults, recurrent bronchitis, bronchiectasis, atelectasis, and nasal polyps are common. Multiple symptoms do not necessarily appear at the same time, but mostly manifest as symptoms of one or two of the systems. 7.Why do patients with primary ciliary dyskinesia have respiratory symptoms? Under normal circumstances, the cilia in the respiratory tract oscillate rhythmically, pushing the mucus felt formed by respiratory secretions to move in one direction at a certain speed to maintain a clean respiratory tract. The oscillation direction of cilia in the nasal cavity is from front to back reaching the nasopharynx, and in the sinuses towards the sinus opening, which ensures the cleanliness of the sinus cavity. cilia ultrastructure abnormalities in PCD patients cause cilia paralysis or loss of oscillation coordination, cilia mucus transport dysfunction, secretion and bacteria retention, which eventually leads to long-term chronic infection, forming recurrent respiratory inflammation, bronchiectasis and sinusitis. 8.Why do patients with primary ciliary dyskinesia exhibit right-sided heart? During the embryonic period, embryonic cilia have the function of guiding the normal embryo to rotate and bend in a right spiral shape, thus leading the heart to the left side, etc. In patients with immobile cilia syndrome, due to the abnormal function of the cilia structure, the cilia are unable to take the guiding role, so that the directional rotation of the internal organs becomes random rotation. In 10-15 days of gestation, the viscera should normally rotate to the right, but instead they rotate to the left, resulting in visceral transposition. 9. Why do patients with primary ciliary dyskinesia have infertility? In males, the sperm tail is a variant of cilia and when its structure is abnormal, the sperm loses its ability to oscillate and can cause male infertility. In women, the surface of the fallopian tube has cilia that oscillate rhythmically to ensure a series of processes such as the transport of the egg and the union of the egg with the sperm. When the cilia structure is functionally defective, the cilia oscillation is lost or the rhythm is disturbed and ectopic pregnancy or even infertility can occur. 10.What tests should be completed to diagnose primary ciliary dyskinesia? ①Blood routine. When the patient has respiratory symptoms, the white blood cells are increased, mainly neutrophils; the blood sedimentation is increased. ②X-ray chest film can help diagnose lung lesions and right-sided heart. ③CT examination can clearly reflect the lesions of sinus, temporal bone and chest, which is significant for disease diagnosis. ④Abdominal ultrasound. Ultrasound examination can understand the presence of visceral transposition, and cardiac ultrasound can also understand the presence of large vessel malformation. ⑤ Abnormalities of cilia or flagellar structures by electron microscopy. ⑥Respiratory NO examination, with reduced nasal and respiratory NO levels in patients with PCD, has now been listed as one of the diagnostic criteria as important as cilia electron microscopy. (7) Sputum culture sputum smear can clarify the pathogenic bacteria of the infection; in patients with right-sided heart, the electrocardiogram shows right-sided heart; echocardiogram can help the diagnosis in those with large cardiovascular malformations. Genetic diagnosis can also be used as a diagnostic tool, but requires genealogical support (family history). 11. How should primary ciliary dyskinesia be diagnosed? PCD is considered when the patient has one of the following conditions: ① chronic rhinosinusitis, chronic bronchitis and other respiratory symptoms since childhood; ② ear, nose and throat lesions are not serious but persistent; ③ there are genetic factors: such as relatives with visceral inversion, or relatives with confirmed immobile cilia syndrome; ④ it can be determined that mucus cilia clearance function is defective or cilia ultrastructure is abnormal; ⑤ semen examination shows reduced sperm activity or (5) Semen examination showed reduced sperm activity or dead sperm and abnormal ultrastructure of sperm flagellum. 12. What is the current genetic research on the disease? Genetic mutations are the basic cause of primary ciliary dyskinesia. Different genes encode different proteins, and each mutated gene can cause various cilia structural abnormalities, so PCD can be broadly classified into 16 types according to different mutated genes and the resulting cilia structural abnormalities. There are 372 genes that have been reported in the literature as being potentially related to cilia structure formation and function production, of which 164 genes have been clearly correlated, and 208 potentially related genes remain to be clarified. Previously, primary ciliary dyskinesia was considered to be an autosomal recessive disorder, and there are now reports on X-chromosome inheritance. Among them, DNAI1, DNAH5, DNAH11, RPGR, TXNDC3, OFD1, DNAI2 and other genes have been clearly related, localized and repeatedly experimentally studied. 13.How should the genetic examination method be selected for patients with disease onset? For disseminated cases, screening of known genes can be performed, but due to the lack of hotspot genes, the workload is large and the screening results cannot be predicted; for patients who show familial onset, the method of gene whole-exome sequencing can be selected, and gene sequencing and analysis of more than 2 patients in the onset family is important for the diagnosis of the disease. 14.How to treat primary ciliary dyskinesia? The main treatment is conservative internal medicine. Apply antibiotics to prevent and control anti-infection; mucus promoter to promote sputum coughing; apply drugs to promote ciliary motility, such as adenosine triphosphate (ATP), standard myrtle oil capsules, amygdalin tablets or injections, eucalyptus citrulline capsules, etc.; improve the immunity of the body and strengthen nutrition, etc. For those with nasal polyps, pulmonary atelectasis, severe cardiovascular malformation and other conservative treatments that are ineffective and have indications for surgery, surgical treatment is available.