SM 167b Lung Pathology & Infectious Disease Flashcards
Is Acute Lung Injury a disease or a syndrome?
Acute Lung Injury is a clinical syndrome
What characterizes Acute Lung Injury?
Abrupt onset of hypoxemia and bilateral pulmonary infiltrates
What can cause Acute Lung Injury?
Infection, physical injury, inhaled irritants, and chemical injury
What is the pathophysiology of Acute Lung Injury?
Related to pneumocyte or endothelial cell injury which triggers an inflammatory response
How can an Acute Lung injury progress?
It can resolve entirely or progress into interstitial fibrosis
What is the pathology correlate of Acute Lung injury?
Diffuse Alveolar Damage
What characterizes Diffuse Alveolar Damage?
Intraalveolar dense pink hyaline membranes, and increased inflammatory cells
What are common causes of bacterial pneumonia?
S. pneumonia, H. influenza, M. catarrhalis, and S. aureus (exudates)
Where can bacterial pneumonia originate?
Community or hospital acquired
What does bacterial pneumonia look like on pathology?
Patchy or diffuse, consolidation of the parenchyma (hepatization), and numerous neutrophils and hyaline membranes within the alveolar spaces
What is bronchopneumonia?
Consolidation of parts of a lobe during bacterial pneumonia
What is lobar pneumonia?
Consolidation of an entire lobe during bacterial pneumonia
What cell types are commonly found in bacterial pneumonia, and where?
Macrophages and PMN’s, commonly in the alveolar spaces
What are common causes of viral pneumonia in immunocompetent hosts?
Influenza A/B, RSV, Adenovirus
What are common causes of viral pneumonia in immunocompromised hosts?
CMV, Herpes
What could predispose a person to viral pneumonia?
Anything that compromises the immune system, such as transplant recipients and advanced HIV
What does viral pneumonia look like under pathology?
Lymphoid infiltrates in the alveolar septae and viral inclusion bodies
How do viral and bacterial pneumonia differ under pathology?
Viral pneumonia affects the alveolar spetae themselves and spares the alveolar space; bacterial pneumonia occupies the alveolar space
How do chronic granulomatous infections present in healthy individuals?
Asymptomatic or subacute
What are common causes of granulomatous infections?
Mycobacteria (TB and non-TB) and fungal (Histo/Blasto/Coccidiomycosis)
How does chronic granulomatous inflammation present on pathology?
Typically, but not always, necrotizing
What must be done to observe fungal organisms on pathology?
Silver stain to highlight fungal causes of chronic granulomatous disease
What must be done to observe bacterial organisms on pathology?
AFB stain to highlight bacterial causes of chronic granulomatous disease
What does a necrotizing granuloma look like?
A patch of cells with a dark core, indicating necrotizing cells
