CSIM1.70 Respiratory D/z 1 Flashcards
Describe bronchopneumonia
Most common pneumonia
Infection of airways, bilateral, bronchi/bronchioles
What organisms cause bronchopneumonia?
Strep pneumoniae, h influenzae, staphylococcus and pseudomonas in immunocompromised
What pathological features can be seen in bronchpneumonia?
Lung consolidation = alveoli filled with fibrin, blood, fluid, inflammatory cells, macrophages and fibroblasts
Multifocal exudates
Difference between bronchopneumonia and lobar pneumonia
Lobar pneumonia is more widespread, infection goes deeper into the lungs, covers a larger area.
Common cause of lobar pneumonia?
Pneumococcus, staphylococcus, klebsiella in diabetics and alcoholics
Progress of lobar pneumonia
1st stage - red hepatisation: alveoli fill with blood in response to toxins and pathogens, consolidates and haemorrhages
2nd stage - grey hepatisation - consolidations solidify due to inflammation and fibrosis.
Possible sequlae of lobar pneumonia?
Resolution if treated
If not
Abscess, empyema, septicaema, fibrosis/scarring
Difference between atypical pneumonia and typical pneumonia?
More varied clinical features
No consolidations/suppurations, no acute inflammatory response
Where does atypical pneumonia pathology occur?
In the lung interstitium, among the pneumocytes and capillaries.
What pathological features does atypical pneumonia cause?
Edema and monocytic infiltrate
What is hyaline membrane formation?
Occurs at the edges of alveolar membrane, inflammation causes it become fibrotic and damaged.
What are common causes of atypical pneumonia in immunocompetent and immunosuppresed patients?
Competent - mycoplasma, chlamydia, legionella, VZV
Suppressed - PCP, aspergillus, candida, CMV, HSZ, VZV
What is a lung abscess?
Complication of pneumonia, localised suppurations caused by necrotic infections. More common in right lung
How can infections be introducd into the lung?
Aspirations, obstructive tumors, direct trauma, infections from other organs
What causes TB, what stain is used?
Mycoplasma tuberculosis, ziehl-nielsen stain.
Transmission of TB?
Inhalation
Describe primary infection of TB
TB goes to lungs, causesd granulamatous response forming a Ghon focus.
Can spread to lymph nodes which is called a Ghon complex.
Usually heals by itself with some calcification and scarring.
What causes disease with TB infection?
The secondary reactivation or reinfection.
Due to sensitisation from primary infection.
Causes type 4 hypersensitivity reaction.
Bacteria causes granulomas + T cell response = necrotising granulomas = casseous necrosis
Symptoms of TB
Fever, night sweats, weight loss, productive cough and haemoptysis.
Where in the lung are TB lesions usually found?
Apices, more oxygen there.
What complications can arise from TB?
Spread to entire lung - tuberculosis bronchopneumonia
Spread to blood - miliary TB
Spread to other organs, adrenal glands, kidney, female genital tract.
