Pulmonary Pathology Flashcards
Anatomic patterns of pneumonia
- patchy: bronchopneumonia
- whole lobe: lobar pneumonia
Pathologic stages of bacterial pneumonia
- congestion
- red hepatization
- gray hepatization
- resolution
Congestion stage of bacterial pneumonia
- gross lung: heavy, boggy, red
- microscopic: vascular engorgement, intra-alveolar fluid, FEW neutrophils, numerous bacteria
Red hepatization stage of bacterial pneumonia
- gross lung: red, firm, airless, liver-like consistency
- microscopic: exudate composed of neutrophils, red cells, and fibrin; filling alveolar spaces
Gray hepatization stage of bacterial pneumonia
- gross lung: grayish brown, dry surface
- microscopic: disintegration of red blood cells, persistence of fibropurulent exudate
Resolution stage of bacterial pneumonia
- microscopic: enzymatic digestion of alveolar exudate to produce granular, semifluid debris that gets resorbed, ingested by macrophages, expectorated or organized by fibroblasts growing into it
Complications of pneumonia paired with pathologic process
- destruction and necrosis w/ accumulation of neutrophils–abscess
- spread of infection to pleural cavity–empyema (intrapleural fibrinosuppurative reaction)
- spread of infection via blood vessels–bacteremic dissemination (heart valves, brain, kidney)
Best example of microorganism for bacterial pneumonia
streptococcus pneumonia
Best example of atypical bacterial pneumonia
mycoplasma pneumonia
Viral/atypical bacterial pneumonia pathology
- infection that leads to inflammation of interstitium
- inflammatory infilitrate compose of LYMPHOCYTES, histiocytes, plasma cells
Viral pneumonia causes
- influenza A and B
- respiratory syncytial virus (RSV)
- human metapneumovirus
- adenovirus
- rhinovirus, rubeola, varicella
Different histologic findings in pneumonia: bacterial vs. viral
Bacterial: located in alveolar spaces, neutrophils
Viral: located in interstitium, lymphocytes
Histologic features of usual interstitial pneumonia
- hetergeneity of interstitial fibrosis
- fibroblastic foci
- honeycomb fibrosis
Histologic features of hypersensitivity pneumonitis
- poorly formed granulomas: non caseating
- interstitial pneumonitis consisting of lymphocytes, plasma cells, macrophages
- interstitial fibrosis and honeycombing (late stage)
Key association with hypersensitivity pneumonitits
BIRDS ARE BAD
Gross lung appearance in sarcoidosis
- multiple small white nodules many next to airways
Histologic features of Sarcoidosis
- non caseating granulomas
- asteroid body
- schaumann body
Location of non necrotizing granulomas in sarcoidosis
- beneath pleura
- along interlobular septa
- bronchovascular bundles
Three most common lung carcinomas
- non small cell carcinoma: adenocarcinoma, squamous cell carcinoma
- small cell carcinoma
Male to female ratios of lung carcinoma
- adenocarcinoma: males 37%, females 47%
- squamous cell carcinoma: males 32%, females 25%
- small cell carcinoma: males 14%, females 18%
5 year survival rate of lung carcinomas
- non small cell carcinoma: 21.4%
- small cell carcinoma: 6.5%
Metastatic carcinoma differences
- more common than primary lung cancer
- most commonly presents as multiple bilateral nodules (vs. primary lung cancer that usually presents as a solitary lesion)
Squamous cell carcinoma location and histologic findings
- location: centrally in the mainstem, lobar or segmental bronchi
- features: keratinization (eosinophilic dense cytoplasm), pearl formation, intercellular bridges
Small cell carcinoma location and histologic findings
- location: central or peripheral
- small cells, scant cytoplasm, granular nuclear chromatin (salt and pepper pattern), high mitotic rate, nuclear molding
