Mycobacterium & Mycoplasma Flashcards
what is the bacteria that causes TB
mycobacterium tuberculosis
whats TB commonly linked to
disease risk linked to immune status HIV
what si the resistance rate of TB
1.5-6% stabel
what si the pathogenesis of TB
inhale penetrate lungs lesion = pulmonary epi and macrophages phagocytosis persist and replicate local immune resp and inc macrophages destroy cells granulomatous lesion
why is TB described at persistent infection
tyco TB + cell wall frags to lymph nodes stim more macrophages around body immune respones leaves infected macrophages and some tubercle ba dormant or lyse
what si the reactivation of tb
if primary lesions fail to heal by becoming fibrous and calcified can lead to tubercle tat is prone to reactiavtion
reactivation can be lined to
immune system
- age, stress, malnutrition, alcoholism, immunosuppression, drugs
what are th symptoms of tb
limited to lungs cellular immunity halts replication mailais weight loss cough night fever productive cough
what is the diagnosis of tb
1 = +ve skin test using tuberculin
2 radiographic evidence of pulmonary disease
3 lab diagnosis of mycobacteria
what si the tubercle skin test
use purified protein derivative
inject intradermally
detects presence of sensitised T cells
what are the characteristics of mycobacteria
non motile non spore form aerobic bacilli complicated cell wall (rich lipids) fastidious slow grow
what is the waxy cell wall all about
60% lipid
mycolic acid
complexed with polysaccharides
hydrophobic waxy cell wall
what is LAM in the cell wall
LipoArabinoMannan
what are the lab diagnosis experiments
sputum specimen
- smear fluorescent
- culturing
- solid media
nucleic acid amplification
- sp as culturing and results in 8 hours
how is TB treated and controlled
isoniazid (primary Ab)
Rifampicin
Pyrazinamide
Ethambutol
