Canis ISSN: 2398-2942

Primary ciliary dyskinesia

Synonym(s): Primary ciliary dyskinesia (PKD, immotile cilia syndrome, Kartagener's syndrome

Contributor(s): Kyle Braund

Introduction

  • Rare inherited defect in microtubule formation affecting respiratory and other cilia (eg urogenital tract, auditory canal) in pedigree dogs.
  • Signs: early onset rhinosinusitis and recurrent bronchopneumonia. Infertility common. Situs inversus in 50%.
  • Diagnosis: clinical signs, radiography, bronchoalveolar lavage, sperm samples, cilia function tests, electron microscopy of cilia.
  • Treatment: symptomatic for recurrent bronchopneumonia.
  • Prognosis: guarded to poor.

Pathogenesis

Etiology

  • Normally autosomal recessive condition (occasionally possibly dominant) resulting in dysfunction of ciliated epithelia.

Predisposing factors

General
  • Neonatal bacterial rhinits.

Specific

  • Inbreeding of pedigree dogs.

Pathophysiology

  • Inhereted abnormality of function and usually structure of clilia results in effects in all ciliated epithelia in body.
  • Respiratory signs predominate due to poor mucociliary carpet clearance of mucus.
  • Cilia in other organs also affected.
  • Subclinical hydrocephalus Hydrocephalus and otitis media Otitis media in most cases.
  • Wide variety of defects described involving various parts of the ultrastructure of the cilia. Some cases have normal cilia ultrastrucutre but abnormal orientation and motility.
  • Cilia defects vary between breeds but consistent within one breed and between organs of one dog.
  • Clinical signs similar for all described cilia defects.
  • Note - Kartagener's syndrome is a specific form of PCD characterized by the triad of situs invertus (right-to-left transposition of thoracic and abdominal organs), chronic rhinitis and sinusitus and bronchiectasis.

Pathological process
  • Ultrastructural and functional defect of cilia lining nose and airways → ineffective clearance of mucus → trapping of bacteria in lower airways and nose → recurrent bacterial infections → rhinosinusitis and bronchopneumonia → stimulation of further mucus secretions and weakening of bronchial walls → blockage of lower airways with mucus → air trapping, bulla formation, bronchiectasis and consolidation of ventral (dependent) lung lobes.
  • Neonatal bacterial rhinitis especially associated with pasteurella Pasteurella multocida can → hypoplasia of nasal turbinates, atresia of frontal sinuses and rhinoliths.
  • Ventilation - perfusion mismatch results from lung consolidation and airway obstruction → hypoxia and hypo or normocapnia.
  • Pulmonary artery hypertension results from chronic respiratory disease → cor pulmonale Cor pulmonale in some chronic cases.
  • Chronic bacterial infections provide a stimulus for hepatic production of serum amyloid A → amyloidosis Amyloidosis in some cases.
  • Ciliary dysfunction in auditory tube → subclinical otitis media Otitis media in most dogs.
  • Abnormal CNS ependymal cilia resulting in impaired CSF drainage or another poorly understood reason → subclinical hydrocephalus Hydrocephalus.
  • Impaired ciliated function in spermatozoa → female infertility Infectious infertility in the female in most cases.
  • Postulated ineffective ciliary motility in embryo → random organ orientation → mirror image organs and thorax +/- abdomen (situs inversus) in 50% of cases. Mechanism may be simply genetic.

Timecourse

  • Continuous respiratory signs gradually worsening with superimposed more acute episodes of severe bacterial bronchopneumonia.

Diagnosis

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Treatment

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Prevention

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Outcomes

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Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Watson P J, Herrtage M E, Peacock M A & Sargan D R (1999) Primary ciliary dyskinesia in Newfoundlands. Vet Rec 144 (26), 718-725 PubMed.
  • Schidlow D V (1994) Primary ciliary dyskinesia (the immotile cilia syndrome). Annals of Allergy 73 (6), 457-469, quiz 468-70 PubMed.
  • Crager C S (1992) Canine primary ciliary dyskinesia. Comp Cont Educ Small Anim 14 (11), 1440-1444 VetMedResource.
  • Edwards D F et al (1992) Primary ciliary dyskinesia in the dog. Probl Vet Med 4 (2), 291-319 PubMed.
  • Edwards D F et al (1989) Familial immotile-cilia syndrome in English Springer Spaniel dogs. Am J Med Genetics 33 (3), 290-298 PubMed.

Other sources of information

  • Johnson L (2000)Disease of the bronchus. In:Textbook of Veterinary Internal Medicine, 5th edn. Eds: S J Ettinger & E C Feldman. Philedelphia: W B Saunders Co. pp 1055-1061.


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