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
how long is the long course of Ab treatment for TB
6-9 months
what sit h vaccination for TB like
bacille palmette guerin
attenuated M BOVIS
enhances aiblity macrophages to become activated and kill
what is the oral representations of real TB
normally secondary lesions
in AIDS increased
at back mouth
cervical lymph nodes
explain some facts about mycoplasma pneumonia
primary atypical pneumonia
trans by resp droplets
lower rep tract
sporadic
what are the symptoms assc with mycoplasma pnemoaniae
gradual onset
non sp symptoms ( headache, fever, chills)
diffuse bronchopneumonia
immunocompromised offer from rash, CNS disturbance, mild haemolytic anaemia
what is the mycoplasma sep like in general
smallest free living organism
vary shape
no cell wall
fastidious
what is th culture media like for mycoplasma spp
enriched yeast extract
serum and sterols
what is transmission of mycoplasma spp
resp droplets
shed in saliva prior ro disease
what sit he pathogenesis of mycoplasma spp
attaches via P1 surface p
binds sialic acid rich glycolipids on ciliated bronchial epi cells
infiltration of lymphocytes and macrophages lead to thicken of cell wall of alveoli and bronchioles
what is the diagnosis of mycoplasma sppp
sputum analysis by nucleic acid hybridisation
serological tests
how treat mycoplasma spp
erythromycin
teracyline
what sit he problem assc with mycoplasma and treatment
slow growing
slow to respond to treatment
may persist in upper resp tract
