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Group Common Human Pathogens
Tuberculosis M. tuberculosis
M. bovis
M. martasan
M. kansasii
M. scrofulacman mycobacteria, tuberculosis
M. xenopei
M. avium
M. mtraceilulara
M. haemophdum mycobacteria, tuberculosis
IV (rapid growers) M. formitum
M. chelonei (M. abscessus)
Highest risk for progression to disease:
· Infants and adolescents; recent contacts with an infectious patient; recent skin test convertor; immunodeficiency HIV); IVDU
· Certain diseases - Hodgkin's, lymphoma, diabetes mellitus, chronic renal failure, malnutrition, immunosuppressive drugs (daily steroids)
Transmission: Inhalation (droplet nuclei); duration of infectivity - few weeks (adult, effective therapy, susceptibilities, smear positivity, cough frequency, adherence to therapy)
Early Disease (1 to 6 Months after Infection)
· Lymphadenopathy: Hilar, mediastinal, cervical, supraclavicular
· Pulmonary: Lymphadenopathy, lobar, segmental, pleural, miliary
· Extrapulmonary: meningitis, miliary
Late Disease (Months to Years)
· Pulmonary: Reactivation (adolescents, immunocompromised)
· Extrapulmonary: Middle ear, mastoids, bones, joints, skin
Occurs in approximately 20% of children less than 5 years of age
Tuberculin testing
· Tuberculin reactivity: