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174.e2 Ciliary Dyskinesia, Primary

Ciliary Dyskinesia, Primary Client Education
Sheet
VetBooks.ir Etiology and Pathophysiology

BASIC INFORMATION
• The mucociliary escalator is a major contribu- intracellular bacteria; samples should be
cultured.
Definition tor to physical defense of the airways. • MRI or CT imaging of brain may identify
A rare congenital disorder in which defective • Pathogens and particulates are normally hydrocephalus but is rarely performed.
ciliary motility leads to impaired mucociliary trapped in a layer of mucus overlying the • Nuclear scintigraphy: technetium-99
transport and recurrent respiratory infection ciliated epithelium. macroaggregated albumin is deposited at
• Synchronized movement of the cilia propels the carina, and movement is followed with
Synonyms entrapped pathogens and particles orad for a gamma camera for 30 minutes. Isotope
Immotile cilia syndrome, Kartagener syndrome, removal from the airways. fails to move orad in dogs with congenital
PCD • In animals with PCD, structural and/ or acquired ciliary dysfunction.
or functional defects in the cilia lead to • Electron microscopy: ultrastructural defects
Epidemiology uncoordinated, asynchronous ciliary motion, can be detected on glutaraldehyde-fixed biop-
SPECIES, AGE, SEX and ineffective clearance of pathogens and sies of nasal or tracheal mucosa, but detection
Young dogs of either sex; rarely occurs in cats. particles trapped in the mucous layer. is technically demanding. Samples should
Clinical signs begin between several weeks of • Failure of the mucociliary escalator results in be sent to a pathologist with experience in
age up until a few years, but most become recurrent bacterial infection of the airways. interpreting these biopsies. Alternatively,
apparent between 4 and 10 months of age. ciliated epithelium may be cultured in vitro
DIAGNOSIS and resultant tissues examined by electron
GENETICS, BREED PREDISPOSITION microscopy.
Numerous breeds of dogs are affected with Diagnostic Overview • Ciliary beat frequency and synchronization:
primary ciliary dyskinesia (PCD). A monogenic The diagnosis is suspected in a young dog with technically demanding process requiring
autosomal recessive pattern of inheritance has recurrent respiratory infections. When identi- special equipment; allows functional observa-
been demonstrated in Newfoundland dogs. fied, situs inversus or defective sperm motility tion of cilia from freshly obtained biopsies;
A causative gene mutation in Old English are strongly supportive. Definitive diagnosis impractical in most instances.
sheepdogs is also transmitted with an autosomal requires biopsy and analysis of biopsy tissue
recessive pattern. with electron microscopy. TREATMENT
ASSOCIATED DISORDERS Differential Diagnosis Treatment Overview
• Rhinitis, sinusitis, and pneumonia occur as • Secondary (acquired) ciliary dyskinesia Affected animals typically require repeated
a result of PCD. ○ Primary respiratory infections/inflamma- courses of antimicrobials throughout life to
• Bronchiectasis results from repeated airway tory airway disease control infection because there is no treatment
infections. ○ Inhalation of toxic substances (e.g., smoke) for the primary disease.
• Defective ciliary function in other organs • Noninfectious respiratory inflammatory
may lead to male infertility, hydrocephalus, disease (e.g., lymphoplasmacytic rhinitis, Acute General Treatment
or otitis media. eosinophilic bronchopneumopathy, aspira- • Appropriate antimicrobial therapy, based
• Situs inversus (mirror-image reversal of the tion pneumonia with secondary airway ideally on culture and sensitivity (C&S)
position of organs in the body), bronchiec- damage/bronchiectasis) results from tracheal or bronchial lavage
tasis, and PCD define Kartagener syndrome, • Congenital immunodeficiency syndromes of samples
seen in a subset of animals. dogs and cats (p. 1260) ○ Before C&S available, use broad-spectrum
• Chronic bacterial or fungal respiratory coverage.
Clinical Presentation infections treated inappropriately or from ○ Choose bactericidal rather than bacterio-
HISTORY, CHIEF COMPLAINT infection with atypical pathogens static antimicrobials.
Young dogs present with signs of recurrent • For dogs with pneumonia (p. 795)
upper and/or lower respiratory tract infection. Initial Database ○ Consider oxygen supplementation if
Nasal discharge, sneeze, and cough are common • CBC respiratory distress is present in the face
features, and dyspnea occurs less frequently. ○ Neutrophilic leukocytosis likely if pneu- of hypoxemia (PaO 2 < 80 mm Hg or SpO 2
Infections often improve dramatically with monia is present < 94%).
antibiotic treatment but recur after cessation • Serum biochemistry: nonspecific ○ Maintain hydration with parenteral fluids
of antibiotics. Sometimes, several littermates • Thoracic radiographs: as needed.
or other pups from the same breeding pair ○ Alveolar, bronchiolar, and/or interstitial ○ Encourage expectoration of mucus
are recognized as having similar histories of lung patterns may be observed. from airways by saline nebulization and
recurrent respiratory infection. ○ Bronchiectasis coupage. Avoid cough suppressants.
○ Situs inversus is detected in about one-half
PHYSICAL EXAM FINDINGS of affected dogs (apex of the heart points Chronic Treatment
• Bilateral mucoid to mucopurulent nasal to the right; lung anatomy is reversed on • Repeated courses of antimicrobial drugs are
discharge the median plane) and is strongly sug- required for recurrent infections.
• Sneezing gestive of PCD in young animals with • Avoid treatment with cough suppressants.
• Coughing (often moist, productive) respiratory infection. • Avoid exposure to respiratory irritants, such
• Dyspnea with crackles when pneumonia is as cigarette smoke.
present Advanced or Confirmatory Testing
• Fever possible when pneumonia is present • Semen evaluation: abnormal motility of Possible Complications
• Rarely, evidence of hydrocephalus (e.g., spermatozoa; primary morphologic anomalies • Bronchiectasis
dome-shaped head, abnormal neurologic • Tracheal wash or bronchoalveolar lavage: • Pneumonia
exam) neutrophilic inflammation, often with • Sepsis
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