Micro Tuberculosis Flashcards
Primary tuberculosis
initial case of tuberculosis
Secondary Tuberculosis
reactivated tuberculosis
Disseminated tuberculosis
tuberculosis involving multiple systems (miliary TB)
Aerobic
Acid fast rods (mycolic acid)
grows slowly
facultative intracellular
Mycobacterium tuberculosis
Transmission: inhalation
Virulence: cord factor
Tissue necrosis is due to immune response
Mild fever, Sweating Chest pain Cough (productive, sputum may be bloody) fatigue, Malaise Weight loss
Tuberculosis
RF for Tuberculosis
Poor nutrition, drug users, alcoholics, crowded living conditions, immunocompromised,
endemic areas: SE Asia, sub-saharan African, Easter Europe
TB progression
Inhalation of bacteria, Engulfed by alveolar macrophages
Survive & multiply; Attract and activate more macrophages
Formation of tubercle/granulomas
dormant for yrs/decades (Immunosuppressed)
Tubercles changes over time
Caseous lesion
Ghon complexes
Tuberculous cavities
Testing for TB
PPD test/Mantoux/Tuberculin skin test: positive means exposure
CXR: tubercles
Sputum: Acid fast & fluorescent auramine stain
Lowenstein-Jensen agar
TB treatment
Combination therapy
Treatment consists of 4 drugs: Isoniazid, Rifampin, Ethambutol and Pyrazinamide.
Initial phase: usually 2 months followed by 4 months of continuation phase.
isoniazid if potential exposure
MDR-TB: multidrug resistant
resistant to isoniazid and rifampin
XDR-TB: extremely drug resistant
resistant to isoniazid, rifampin, and fluoroquinolones, as well as either aminoglycosides (Amikacine, kanamycine) or capreomycin. at least one of the 2nd line drugs
BCG Vaccine
Live, attenuated M. Bovis
Weakly gram pos acid-fast aerobic rods mycolic acid in cell wall slow growing in culture normal inhabitants of soil and water
Mycobacterium avium complex MAC pneumonia inhalation primary: similar to TB secondary: in all organs and blood stream, AIDS pts with low CD4+ T cell counts, <50 cells/ml
Immunocompromised
Chronic pulmonary disease
MAC pneumonia RF
Diagnose MAC Pneumonia
acid fast stain
Treatment MAC Penumonia
Clarithromycin or Azithromycin combines with Ethambutol and Rifampin
if you have AIDS give Clarithromycin and Azithromycin
Immunocompromised
Renal transplant
Norcardiosis RF
Gram positive, aerobic
Weakly acid fast staining
branching filaments
Normal found in soil
Nocardia
transmission: inhalation
Fever Night sweats Malaise Chest/abdominal pain Persistent cough Anorexia
Nocardiosis
pulmonary infection, lung abscesses
spread and form abscesses in brain or kidney
Diagnostics for Nocardiosis
microscopy of sputum: branched long rods
culture: blood or chocolate agar
Nocardiosis treatment
IV trimethoprimsulfamethoxazole
Linezolid
