Infectious Disease II Flashcards
(62 cards)
1
Q
what are bacteria pathogens
A
- transient bacterial infections
- localized infections
- systemic infections
- extracellular pathogens
- intracellular pathogens
- toxins
- grow on media
2
Q
what is the causative agent for TB
A
mycobacterium tuberculosis
3
Q
describe TB and the cells seen in the histology
A
- pulmonary infection is most common
- intracellular pathogen
- granulomatous disease
- epithelial histiocytes
- multinucleated giant cells
- lymphocytes
4
Q
what is the prevalnce of TB
A
- 1/3 of the world population infected
- leading infectious cause of death after AIDS
5
Q
what populations are susceptible to TB
A
- homeless
- malnourished
- overcrowded
6
Q
why are active TB cases increasing
A
- HIV infection
-immigration
7
Q
what is infection
A
growth of the organism in a patient
8
Q
what is active disease
A
destructive, symptomatic disease
9
Q
how is TB spread
A
-droplet nuclei of 1-5 microns
- stay airborne for long periods of time
- reach the pulmonary alveoli
10
Q
what is primary pulmonary TB
A
- previously unexposed person
- cell mediated immunity controls infection
- fibrosis and calcification
- viable organisms dormant in lesions - latent disease
- may reactivate if immune defenses are lowered
11
Q
what is seen in primary pulmonary TB
A
Gohn complex- parenchymal lung lesion and hilar nodal lesion
12
Q
what type of mcirobe is TB
A
acid fast bacilli
13
Q
how does mycobacterium TB intracellular pathogen cause virulence
A
TB cord factor- blocks fusion of phagosome with lysozome
14
Q
what area in the oral cavity is susceptible to tuberculous ulcer
A
lateral border of the tongue
15
Q
how is TB diagnosed
A
- chest radiograph
- sputum culture
- molecular biologic tools
16
Q
what is the treatment for TB
A
multi drug regimen
- isoniazid
- rifampin
- ethambuton
- streptomycin
- pyrazinimide
- rifabutin
17
Q
what are the symptoms of active TB
A
-chronic cough
- hemoptysis
- weight loss
- night sweats
- fever
18
Q
describe the mantoux tuberculin skin test: PPD test
A
- type IV delayed hypersensitivity reaction to protein from M TB
- intracutaneous tuberculin injection
- T cells sensitized by prior infection recruited to area
- produces an area of induration
19
Q
what does a positive tuberculin skin test indicate
A
- individual has been infected
-cell mediated hypersensitivity exists - does not indicate active disease
20
Q
what is the bacillus calmette Guerin (BCG) vaccine
A
- live attenuated strain of Mycobacterium bovis
- caused positive PPD reaction
- effectiveness uncertain
- not used in US
21
Q
what is scrofula
A
- tuberculous lymphadenitis of neck
- mycobacterium bovis infection from infected milk
- pasteurization of milk
- tuberculosis control for cattle
22
Q
what is the causative agent of syphillis
A
- treponema pallidum
23
Q
describe syphillis
A
- STD
- sequentail clinical stages
- years of latency
24
Q
what are the 2 forms of syphillis
A
- acquired syphilis- STD
- congenital syphilis - in utero transmission
25
what are the clinical stages of untreated acquired syphilis and how long do each last
- primary: 1 week to 3 months
- secondary: 1-12 months
- tertiary (late) : 1-30 years
26
what is the lesion called in primary syphilis
chancre
27
what are the lesions of secondary syphilis
- skin rash (macular papillary rash)
- mucous patch
- condylomata lata - genital lesions
28
what can happen in tertiary syphilis
- most destructive stage
- gumma
- syphilitic glossitis
- nervous system- neurosyphilis: tabes dorsalis
- CVS: aneurysm of ascending aorta
29
what would a biopsy of a gumma show
granulomatous inflammation
30
which stage of syphilis is infectious
teritary - the gumma lesion
31
what are the lesions of congenital syphilis
- snuffles
- saddle nose
- rhagades
- hutchinson's incisors
- mulberry molars
32
what is hutchinson's triad of congenital syphilis
- blind- intersitial keratitis
- deaf
- dental anomalies
33
what are the laboratory tests for syphilis
- cant culture
- can see with microscopy - dark field or fluorescence microscopy
- serologic tests for syphilis: non treponemal tests - reagin- antibody to cardiolipin
- treponemal tests- specific for T pallidum
34
describe non- treponemal tests
- VDRL - venereal disease research lab
- RPR - rapid plasma reagin
35
describe treponemal tests
- FTA-ABS: fluorescent treponemal antigen absorption
- MHA-TP - microhemagglutinin - treponema pallidum
36
what type of infection is actinomycosis
bacterial
37
what are the types of diseases caused by fungi and what area of body is affected
- superficial: skin, hair, nails, dermatophytes
- subcutaneous- dermis and subcutaneous tissue: sporotricosis
- systemic- deep infections of internal organs: histoplasmosis
- opportunistic- immunocompromised host: candidiasis
38
what is mucormycosis
-fungal infection seen in immunocompromised patients
- possible to se granulomatous inflammation
39
where is histoplasmosis prevalent and how is it transmitted
- endemic to mississippi river valley
- transmission by inhalation of spores from bird droppings or dust particles
40
describe histoplasmosis infections
- sub clinical infection usual
- flu like syndrome
41
describe histoplasmosis deep fungal infection of the lungs
- inhalation of spores
- phagocytosis
- specific immunity
- killing of organism
- dystrophic calcification
42
describe histoplasma capsulatum
- dimorphic fungus- yeast at body temperature, mold in nature
43
what percentage of the population is infected with histoplasmosis
80-90%
44
what is the most common systemic fungal infection in the US
histoplasmosis
45
who is affected by disseminated histoplasmosis and describe the lesions
- elderly, debilitated, immunosuppressed, AIDS
- spreads to extra pulmonary sites
- adrenal lesions- addisons disease
- oral lesions
46
what is coccidioidomycosis and where is it found
- deep fungal infection of the lungs
- 40% develop respiratory symptoms
- disseminated disease may occur
- valley fever
- found in southwestern US
- granulomatous inflammation
47
what are the clinical forms of oral candidiasis
- pseudomembranous (thrush)
- erythematous (atrophic)
- hyperplastic
- angular chelitis (perleche)
- central papillary atrophy
48
describe the appearance of acute pseudomembranous candidiasis
cottage cheese appearance
- when wiped off you will see erythematous base
49
what is the tx for psuedomembranous candidiasis
- fluconazole (diflucan) 100mg
- two tabs on day one and one tab day 2-13
50
what is atrophic candidiasis cultured on and why
- sabauraud agar
- has a low pH and gentamycin to inhibit bacterial growth
51
what is the oral exfoliative cytology for diagnosis of fungal infections
candidal pseudohyphae
52
what is erythematous candidiasis treated with
fluconazole (diflucan) 100mg
- two tabs on day one
one tab on days 2-13
53
what is steroid inhaler candidiasis
- happens when inhaler is held too close
- opportunistic infection
54
where is angular chelitis found
- on corners of mouth only
- seen in patients with loss of VDO
55
what type of prescription is candidiasis treated with
antifungal
56
what does hyperplastic candidiasis look like
leukoplakia but does not rub off
57
what should you look for in a histology slide of candidiasis
sticks and circles
58
what is another name for central papillary atrophy
median rhomboid glossitis
59
where does median rhomboid glossitis appear
only in the midline of the dorsal tongue
60
what is chronic mucocutaneous candidiasis due to
T cell defects
61
describe candidiasis in HIV infections and what should you prescribe
- can be red or white or mixed
- all over the mouth prescribe systemic antifungla
- if in one area of the mouth prescribe topical anti fungal
62
