Micro 9 - Mycobacterial disease Flashcards
2 broad groups of mycobacteria - phylogenetically and clinically
Clinically: mycobacterium TB and non tuberculous mycobacteria
Phylogenetically: slow growing + rapid growing
which subtype of mycobacterium is not grouped and why
M.leprae, not grouped because it cannot be grown
MTB complex consists of
Mycobacterium tB
Mycobacterium bovis
mycobacterium TB slow or fast growers?
slow grower
which group of mycobacteria = fast growers? (<7 days)
Mycobacterium abscessus complex
Name 3 slow growing NTM
Mycobacterium avium intracellulare/ MAC
Mycobacterium marinum
Mycobacterium ulcerous
structure and shape of mycobacteirum
non-motile rod shaped bacteria, structurally gram +Ve
mycobacteria stain used for SCREENING and one used for DIAGNOSIS
Screening: auramine
Diagnosis: Ziehl Neelsen
which NTM most commonly seen in immunocompromised/HIV pts?
MAI/MAC
Will affect immunocompetent w/o HIV if they have pre-existing bronchiectasis/cavities
SWIMMING pool granuloma
Mycobacterium marina
Which NTM results in huge chronic painless ulcers
Mycobacterium ulcerous
M. abscessus/chelonae/fortuitum
What type of mycobacteria are these? when are they seen?
Rapid growing NTM
Hospital setting/ tattoos - skin and soft tissue infections
treatment regimen for NTM (RiCES)
Rifampicin
Clarions/azitro
Ethambutol
+/- streptomycin/amikacin
2 main types of mycobacterium leprae
Paucibacilary tuberculoid
Multibacilary lepromatous
Features of paucibacillary tuberculoid
Few skin lesions + less joint infiltration
Robust T cell response
Features of multibacillary lepromatous
Abundance of bacili
Multiple skin lesions + joint inflammation
Poor T cell response
A 23 year old HEALTHY male is aCLOSE CONTACT of a person with smear positive pulmonary TB, What is his lifetime risk of developing active TB?
10%
3 most common forms of MTB?
Mycobacterium TB
Mycobacterium bovis
Mycobacterium Africanum
Skin manifestation of TB?
Erythema nodosum
what is Ghon focus?
granuloma in the lungs of pts with pulmonary TB
What is post primary TB?
LATENT TB that is reactivated >5 years later
“millet seeds” on CXR
Miliary TB
WHICH LNs most commonly involved in extra pulmonary TB?
Cervical
What is scrofula?
lymphadenitis, some children can get this in response o BCG
