Immunity Immunity
IV hypersensitivity
Koch phenomenon;
wax D+tuberculin protein; wax D →macrophage→epithelioid
cell→tubercles→protect TB being phagocytized
Immunity Immunity
Humoral immunity
A lot of Ab comes out, but meaningless
TB active patient: immune complex more
TB stable patient: immune complex less
Diagnosis Diagnosis
The steps to diagnose TB infection and disease include:
A medical evaluation that includes history and risk assessment
The tuberculin skin test
A chest x-ray
A bacteriological examination
1. Specimen: sputum, pus, CSF, urine, etc
.
2. Microscopic examination: Ziehl-Neelsen stain
3. Concentration: 4NaOH-3HCL; 6 H
2
SO
4
4. Culture :
solid culture 2-4 weeks 37 ;
℃
liquid culture 1-2 weeks
5. Animal inoculation: guinea pig
6. quick Diagnosis: PCR
Skin test Skin test
PPD-C BCG-PPD
5mm + 15mm + +
PPD-CBCG-PPD infected
Mantoux method Mantoux method
When the Mantoux skin test is performed, a needle is injected into the upper skin layer of
the patients arm. The arm is examined 48 to 72 hours after the tuberculin injection in
order to evaluate the reaction on the patients skin. Any swelling that can be felt around the
site of the injection, also known as induration, is measured. The diagnosis of TB
infection depends on the size of the measured induration and the patients individual risk
factors.
BCG vaccination for new infants Freeze-drying vaccine
rRNA vaccine
eg:south India Chingleput’s failure of BCG Find and cure patients
Treated with a combination of multiple drugs for a long period of time: rifampin,
isoniazid INH, pyrazinamide, ethambutol, and streptomycin.
Emergence of multi-drug resistant M. tuberculosis strains.
Mycobacterium avium Mycobacterium avium
and and
AIDS AIDS
•
M. avium M. avium
is much less virulent than is much less virulent than
M. tuberculosis M. tuberculosis
–
does not infect healthy people does not infect healthy people
–
infects AIDS patients infects AIDS patients
•
M. avium M. avium
infects infects
–
when CD4 count greatly decreased when CD4 count greatly decreased
•
M. tuberculosis M. tuberculosis
infection infection
–
infects healthy people infects healthy people
–
infects AIDS patients infects AIDS patients
earlier stage of disease earlier stage of disease
more systemic more systemic
•
systemic disease versus pulmonary systemic disease versus pulmonary
–
greater in AIDS greater in AIDS
•
lesions often lepromatous lesions often lepromatous
Antibiotic therapy Antibiotic therapy
•
selected primarily for selected primarily for
M. tuberculosis M. tuberculosis
•
if if
M. avium M. avium
