Unformatted text preview: depends on: 1) general health 2) age. Adults in good general health more resistant. Elderly, young children, and adults in poor health more susceptible. P/E: nasopharynx → localizes in lungs. Initial lesion develops - tubercle. Histology of tubercle: 1) PMN's, macrophages - inflammation 2) T-lymphocytes - cell immunity 3) Fibroblasts → connective tissue - non-specific resistance. Disease : Two forms disease: 1) Benign TB - self-limiting (heals). Occurs in adults in good health. 2) Progressive TB - spreads. Occurs in elderly, young children, adults in poor health. Lesion continues to develop - caseation. Can spread to other parts body - joint, kidney, intestines, CNS, etc. Arrested TB: Lesions heal but contain dormant organisms; can be reactivated at later date. Skin Test: Injection Ag. → read in 3 days - observe for red, raised hardened area (+). Indicates previous exposure, NOT active illness....
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- Fall '09
- Bacteria, cough, droplet nuclei