| Term | Definition |
|---|
| type IV | type of hypersensitivity rxn to TB that develops 2-4 weeks post-primary infection; causes tissue dmg via granulomas |
| granuloma | limits spread of TB infxn, causes local tissue destruction, indicates type IV hypersensitivity |
| granuloma | collection of epithelioid histiocytes w/ multinucleated giant cells and peripheral rim of lymphos |
| caseating granuloma | well-circumscribed yellow nodule with NECROTIC center |
| IFN-gamma | secreted by CD4+ T cells; activated macrophages to kill organisms |
| CD8+ T cells | kill infected macrophages and mycobacteria --> caseation |
| caseous material | provides inhospitable environment for mycobacteria due to acidity and relative lack of oxygen |
| cord factor | produced by mycobacteria; needed for in vitro growth of TB in serpentine cords; associated with virulence |
| sulfated glycolipids (sulfatides) | produced by mycobacteria; prevent fusion of phagosomes with lysosomes; promote survival or mycobacteria in macrophages |
| primary TB | new TB infection; clinically silent; leads to either localized infxn or progressive primary TB |
| Ghon focus | focus of primary TB infxn; usually in lower part of UL or upper part of LL (receive greatest airflow); caseating granuloma w/ acid fast bacilli |
| Ghon complex | = Ghon focus + involved tracheobronchial lymph node(s) (also develop caseating granulomas) |
| localized TB infection | from primary TB, infected site undergoes fibrosis, calcification, and ossification; dormant but viable (usual outcome) |
| progressive primary TB | from primary TB, primary lung focus enlarges and spreads; NOT apical lesions; more common with HIV infxn |
| secondary TB | aka postprimary or reactivation TB; infxn in previously sensitized person; bacteria endogenous (common) or exogenous (less common); caseating granulomas in APICAL segments b/c of higher pO2 |
| fibrocalcific TB | aka "arrested" TB; granulomas undergo fibrosis, calcification |
| progressive pulmonary TB | infection spreads, leads to 1) cavitary fibrocaseous TB, 2) tracheobronchial TB, 3) TB pneumonia |
| cavitary fibrocaseous TB | caseating granuloma erodes into bronchus and drains, forms a cavity; apical or w/ large area of necrosis |
| tracheobronchial TB | infected material gains airway access, seeds mucosal lining or bronchi, trachea, larynx --> masses and ulcers, or intestinal TB if swallowed |
| tuberculous pneumonia | aka "galloping consumption"; consolidation of a whole lobe or portion of lobe; often w/ reduced immunity/defenses |
| miliary TB | lymphatic or vascular invasion by bacilli --> dissemination in lung or systemically (granulomas) |
| progressive isolated-organ TB | one organ (e.g. meninges, kidney, bones) develops progressive involvement while other foci heal |
| Simon's focus | 1-3 cm area of caseating granulomas in apical or posterior segments of UL, adjacent to pleural surface; like O2 |
| atypical mycobacteria | non-tuberculous; found in environment; cause opportunistic pulmonary infxns; similar pathology to TB; drug resistant |
Combine with other sets
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