Primary ciliary dyskinesia (PCD) is a rare genetic disorder that causes a defect in the action of the cilia lining the respiratory tract (lower and upper, sinuses, Eustachian tube, middle ear) and fallopian tube, and also of the flagella of sperm in males. It is a congenital disorder caused by ciliary dysfunction.
Cilia are complex, microscopic hairlike structures, capable of movement, that line various body organs, including upper and lower respiratory tracts, auditory tubes, ventricals of the brain, spinal cord, uterine tube and ducts of testes. These cilia move cells or fluids as well as serve as filters (they filter dirt and other material from inhaled air). The ciliary movement is normally coordinated by an intricate interaction of numerous proteins contained within each cilium. In PCD, the movement is either discoordinated (dyskinetic) or completely absent.
This genetic disorder occurs in breeds like bichon frises, border collies, bull mastiffs, Chihuahuas, shar peis, chow chows, Dalmatians, Doberman pinschers, English cocker spaniels, English pointers, English setters, English springer spaniels, golden retrievers, Gordon setters, long-haired dachshunds, miniature poodles, Old English sheepdogs, Newfoundlands, rottweilers, and Staffordshire bull terriers.
Symptoms of PCD typically develop from early age – from few days to 5 months. Some dogs, however, remain symptomatic for prolong periods, from six months to ten years. Symptoms of PCD are
Moist, productive cough that may be elicited by exercise
Bilateral nasal discharge with mucous and pus
Rapid breathing, shortness of breath, and pale tissues may be observed
Chronic sneezing and coughing – may produce copious amounts of mucous and pus. Despite dramatic response to antibiotics, patients may have continuous nasal discharge and will relapse after treatment is stopped
Family history: large litters tend to have more than one affected animal; progeny from prior mating of the dam and sire may have been affected
Tends to occur in young purebred dogs
Fertility: females remain fertile, males characteristically do not