Several nematodes and one trematode live in the airways, lung tissue or pulmonary arteries of dogs. Most infections are uncommon in North America and many are subclinical, but Angiostrongylus vasorum can kill through bleeding or respiratory failure, and Paragonimus kellicotti can cause sudden pneumothorax. For the exam, the hard part is matching each parasite to how the dog caught it, where it lives and which fecal test will find it.
Key facts
Parasites, internal, respiratory at a glance- Species and system: dog (most species also infect wild canids, and foxes are the main reservoir for several); lower respiratory tract and pulmonary circulation.
- Direct life cycle (no intermediate host): Oslerus (Filaroides) osleri, Filaroides hirthi and Eucoleus aerophilus.
- Indirect life cycle: Angiostrongylus vasorum and Crenosoma vulpis (slugs and snails); Paragonimus kellicotti (aquatic snail, then crayfish).
- Classic presentation: chronic cough in a young dog; add bleeding for A. vasorum, tracheal nodules for Oslerus, and pneumothorax for Paragonimus.
- Key tests: Baermann for motile larvae, centrifugal flotation for sluggish larvae and capillarid eggs, sedimentation for fluke eggs, serum antigen for A. vasorum.
- Zoonotic: people get Paragonimus from raw crayfish, not from dogs; human Eucoleus aerophilus infection is very rare. CAPC lists no human hazard for the other species.
What's inside
12 sections in the full guide- Key facts
- How the NAVLE tests this
- Cause and pathophysiology
- Clinical signs
- Diagnosis
- Differential diagnoses
- Treatment and management
- Prevention, control and public health
- Prognosis
- Quick review
- Test yourself
- References
The full guide also has 5 tables, 3 figures, 3 self-test questions and 16 references, available to NAVLE members.
Read the full study guide
The full guide is part of every NAVLE plan, with diagnosis and treatment tables, figures, a quick review and self-test questions. Start a free trial to try the question bank, or log in if you are already a member.