Mycoplasmal, Mycobacteria

Question 1

Mycoplasma pneumoniae

Answer 1

smallest free living prokaryotes that lack ridged cell walls
causes acute, self limited lower respiratory infections
think that host immune system mediates damages as this disease rarely affects children under age of 5
patchy conolidation in single segment of lower lung lobe
“walking pneumonia” in that it tends to be mild but can be associated with Stevens-Johnson syndrome

Question 2

Myobacterium tuberculosis

Answer 2

Acid fast, obligate aerobe
sperical granuloma with CASEOUS NECROSIS
Primary = immunocopetent will mount a vigrouous granulmoatous reaction and wall off the organism. Organism becomes latent in the GHON complex.
Progressive primary TB = Immune deficient and very young will not wall off and disease will become active right away
Secondary TB = latent TB reactivates when host immune system worsens. Get T-cell mediated tissue necrosis and production of tuberculosis cavities.
fever, weight loss, fatigue, night sweats, hemoptysis

Question 3

Myobacterium leprae

Answer 3

weakly acid fast rod that cannot be cultured on artifical media or in cell culture.
Grows best at very low temperatures
transmitted after years of intimate contact or armadillos
TUBERCULOID LEPROSY = single/very few lesions of skin. Langehans giant cells, swollen nerves, sensory deficits, minimal disfigurement
Lepromatous Leprosy = multiple tumor like lesions of skin. Macrophages dont kill the bacili but rather incubate them.

Question 4

Mybacterium avium-intracellulare

Answer 4

found in soil, water and foodstuffs
Granulomatous disease = immunocompetent. resembles TB but much more slowly. Pulmonary nodules and caseating granulomas (lack fever, weight loss, night sweats, and fatigue)
Disseminated infection = 3rd most common disease in AIDS . Find foamy macrophages stuffed with acid fast bacilli throughout the body and organs

Question 5

Myobacterium Kansassi

Answer 5

chronic granulomatous pulmonary disease similar to TB and MAI. found in soil, dust, water

Question 6

Myobacterium scrofulaceaum

Answer 6

draining granulomatous cervical lymphadenitis in young children
found in soil

Question 7

Myobacterium marinum

Answer 7

produces a localized nodular skin lesion

found in water. think swimming pools or aquariums

Question 8

Myobacterium ulcerans

Answer 8

severe ulcerating skin disease in australia, africa, and New Guinea.
Enviromental

Question 9

Myobacterium chelonae and fortuitum

Answer 9

ubiquitous in environment

painless, fluctuant, abscesses at site of innoculation that ulerate and gradually heal spontaneously.