Equine respiratory 1 Flashcards
Oxygen toxicity is more likely to be seen in neonatal foals mechanically ventilated with increased levels of 02 (Fi02>50%) for several days. Which statements is correct
a) It’s frequently followed within a few days by opportunistic bacterial pneumonia
b) Can produce interstitial pneumonia and alveolar type II cell proliferation
c) Can result in lysis of the macrophage, chronic alveolitis, and fibrosis
d) Can result in bronchopneumonia and alveolar type I cell proliferation
b) Can produce interstitial pneumonia and alveolar type II cell proliferation
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) comprise a syndrome of severe pulmonary dysfunction and respiratory failure that affects foals. Which of the following statements is correct?
a) The fraction Pa02/Fi02 is >300mm Hg in cases of ALI (which is the less severe form) and >200mm Hg for ARDS.
b) It is related to pulmonary surfactant deficiency in neonatal foals
c) The pathophysiology includes dysregulation of pulmonary inflammation and coagulation
d) It is not related to an infectious etiology
c) The pathophysiology includes dysregulation of pulmonary inflammation and coagulation
ALI or ARDS arises as a complication after major infectious or noninfectious bodily injury. When this occurs, a protective response starts that involves controlled activation of the inflammatory and coagulation system. In ALIARDS an imbalance of pro inflammatory and anti-inflammatory factors produce an uncontrolled pulmonary inflammatory response and pro coagulation environment in alveoli and the pulmonary microcirculation.
Negative prognostic indicator in R. equi pneumonia
- Intra-abdominal abscess
- Osteomyelitis
Most important immune cell for R. equi
T lymphocytes?
Diagnosis of Chronic carrier state for S. equi
Guttural pouch fluid/swab PCR
Fungi that most commonly causes pneumonia in horses
Coccidiomicosis
Horse with a nasal granuloma (mass), histopathology revealed large amounts of eosinophils around the lesions
Condidiobolus coronatus
What is the best immune response against R. equi:
IFN-y
Elimination of EIV Australia
canary pox 14 days
Drug of choice of Pneumocystis carinii
TMS
Immune response in R. equi pneumonia
IFN-g –> macrophages
Which is the desired immunological response in cases of R. equi pneumonia?
Type 1 response:
This is characterized by the production of antigen-specific Th1 lymphocytes, which allow for clearance of intracellular R. equi via the production of IFN-g and the activation of macrophages, and by antigen specific cytotoxic T lymphocytes which recognize and kill R. equi infected cells.
Which immunological response is detrimental for foals infected with R. equi?
Th 2 response:
Predicted to develop potentially life-threatening pulmonary lesions
Gene associated with virulence in R. equi, and where is it located?
Vap A gene, located in the pathogenicity island (PAI)
These genes are necessary for the correct functioning of the main virulence factor of R. equi, so the bacteria can replicate and survive in the macrophages. Y’all know what I’m talking about?
VirR and Orf
Each of them encondes a regulatory protein
Receptor used by macrophages to engulf opsonized R. equi
Complement receptor 3 = CR3 or Mac-1