Mr. Peepers is a 1-year old intact Bichon Frisé. He was referred to your veterinary internal medicine clinic by his primary veterinarian because of a history of multiple episodes of severe respiratory distress, including congestion, coughing, sneezing, and nasal discharge, but no ocular discharge. The symptoms began when he was about 6 to 7 months old. he has a littermate who has similar symptomatology, but not so severe.
His owner had had new carpet installed and she initially thought that fumes from the carpet or adhesive were causing the problem, but its persistence for months seemed to rule out any form of toxicity. His primary veterinarian, suspecting a low-level an infection, treated him repeatedly with antibiotics: while there was some intermittent improvement after these treatments, he always regressed and began coughing again.
A physical exam at your clinic showed nothing remarkable beyond his being very thin (3/9 BCS), which his owner said was always the case. Blood chemistry and CBC were normal. Bronchoscopy and broncheal/alveolar lavage were done to obtain cultures; and a biopsy was taken for analysis by transmission electron microscopy (TEM). Bronchoscopy showed the larynx and trachea to be completely normal; there was visual evidence of increased mucus in the lungs and erythema in some bronchi.
The preliminary clinical diagnosis, later confirmed by TEM, was chronic pulmonary disease caused by primary ciliary dyskinesia (PCD), also called "immotile cilia syndrome."
Points to Ponder:
What's the role of cilia in the respiratory tract and why would "immotile" cilia ("dyskinesia" is Medical-Speak for "not moving properly," and sounds much more impressive) be an issue? What are they not doing?
What conditions can you think of that would produce cilia that are "immotile" in the first place?
Is this condition caused by external or endogenous factors? What arguments can be put forward for either or both origins?
Why was it necessary to get a TEM consult to confirm the preliminary diagnosis? You can see cilia in the light microscope...why wasn't LM imaging enough?
What treatment(s) can be applied to help this pup?
What's his prognosis? What are you going to tell the owner to expect?