[MICRO] DISEASES OF EYE Flashcards by Aseel Maher

normal biota of eye

staph. epidermidis
Lactobacillus
Propionibacterium

How well did you know this?

Not at all

Perfectly

defense mechanisms of eye

eyelashes
eyelids
lacrimal & goblet cells secretions
lysozymes & IgA

How well did you know this?

Not at all

Perfectly

infections of eyes are MC caused by

staph. aureus

How well did you know this?

Not at all

Perfectly

infections of eyelids cause

blepharitis

How well did you know this?

Not at all

Perfectly

infections of eyelid glands/follicles cause

sties

How well did you know this?

Not at all

Perfectly

gram + cocci
beta hemolytic
catalase +
coagulase +

staph. aureus

How well did you know this?

Not at all

Perfectly

causative agent of conjuctivitis
ferments mannitol
produces golden yellow endopigment
penicillin resistant

staph. aureus

How well did you know this?

Not at all

Perfectly

virulence factors of staph. aureus (7)

1-protein A
2-clumping factor bound coagulase
3-antiphagocytic capsule
4-coagulase enzyme
5-beta lactamases
6-alpha toxin
7-P-V leukocidin

How well did you know this?

Not at all

Perfectly

gram +
lancet shaped diplococci
alpha hemolytic
(-) by optochin
bile soluble

strept. pneumoniae

How well did you know this?

Not at all

Perfectly

virulence factors of strept pneumoniae (2)

antiphagocytic capsule
IgA protease

How well did you know this?

Not at all

Perfectly

conjunctivitis:
gram + lancet shaped diplococci producing alpha hemolytic colonies on blood agar

strept. pneumoniae

How well did you know this?

Not at all

Perfectly

gram - rods
requires factor X & V for growth

H. infleunza

How well did you know this?

Not at all

Perfectly

virulence factor of H. influenza (2)

antiphagocytic capsule
IgA protease

How well did you know this?

Not at all

Perfectly

gram -
kidney bean diplococci
oxidase positive

N. gonorrhea

How well did you know this?

Not at all

Perfectly

N. gonorrhea virulence factors (2)

Pili
IgA protease

How well did you know this?

Not at all

Perfectly

non enveloped double stranded dna virus

adenovirus

How well did you know this?

Not at all

Perfectly

causative agent of non specific follicular conjunctivitis

adenovirus

How well did you know this?

Not at all

Perfectly

causative agent of acute pharyngoconjunctival fever

adenovirus serotype 3

How well did you know this?

Not at all

Perfectly

unchlorinated swimming pools are associated w/ outbreaks of

adenovirus

How well did you know this?

Not at all

Perfectly

non enveloped single stranded RNA viruses

Enterovirus 70
Coxsackie virus A24

How well did you know this?

Not at all

Perfectly

outbreaks of severe hemorrhagic conjunctivitis are caused by

enterovirus 70
Coxsackie virus A24

How well did you know this?

Not at all

Perfectly

enveloped double stranded DNA

Herpes simplex virus-1

How well did you know this?

Not at all

Perfectly

virus which establishes latent infection in trigemnial ganglia in immunocompromised patients

herpes simplex virus-1

How well did you know this?

Not at all

Perfectly

virus causing neonatal conjunctivitis accompanied by generalized herpes

herpes simplex virus-1

How well did you know this?

Not at all

Perfectly

MOT of conjunctivitis

direct indirect autoinoculation

autoinoculation occurs in case of conjunctivitis caused by

N.gonorrhea C.trachomatis

red eye excessive lacrimation purulent/watery discharge are symptoms of

conjunctivitis

fever pharyngitis conjunctivitis are symptoms of

acute pharyngoconjunctival fever (PCF)

causative agents of neonatal conjunctivitis

C.trochamatis N.gonorrhea Staph. aureus Strept. pneumoniae

most common causative agents of neonatal conjunctivitis

C.trochamitis N.gonorrhea

neonatal conjunctivitis is prevented by

erythromycin drops/ointment after delivery

prevention of Chlamydial conjunctivitis

oral erthyromycin

leading cause of non traumatic blindness

C.trochamitis

non motile coccoid obligate IC bacteria

Chlamydiae

cc of Chlamydiae

1-rigid wall 2-no peptidoglycan layer 3-group-specific, species-specific, immunotype-specific antigens 4-15 immunotypes (A-L)

group specific lipopolysaccharide Ag are detected by

complement fixation tests

species-specific & immunotype-specific Ag are detected by

immunofluorescence

chlamydiae immunotypes causing trachoma

A,B, C

chlamydiae immunotypes causing genital tract infections

D-K

which chlamydiae immunotypes cause inclusion conjunctivitis

D-K

chronic conjunctivitis endemic in africa & asia

trachoma

MOT of trachoma

finger-to-eye fomite-to-eye

which cells does chlamydiae infect

epithelial cells of mucous membranes

chlamydiae rarely causes___

invasive disseminated infections

pathogenesis of trachoma

1-multiplies within conjunctival cells 2-kills cells 3-pus filled discharge 4-eyelids turn inwards 5-eyelashes scar cornea 6-scarring triggers invasion of BV 7-cornea no longer transparent

metabolically inert form of C.trachoma

elementary body

metabolically active form of C.trachoma

reticulate body

replication cycle of C.trachoma

1-elementary body enters cell 2-elementary body reorganizes into reticulate body 3-cycles of binary fission 4-daughter reticulate bodies 5-reticulate bodies develop into elementary bodies 6-progeny elementary bodies released

C.trachoma is stained & visualized through

inclusion bodies (site of replication within cells)

mild conjunctival discharge inflammation pebbled appearance of upper eyelid impaired vision

trachoma

infants born to mothers w. trachoma develop

mucopurulent conjunctivitis

cc of inclusion conjunctivitis

cornea isn't affected affects lower lid recovery

Reiter's syndrome

autoimmune antibodies against C.trachoma cross react with antigens on urethra, joints, uveal tract

trachoma vaccine

NONE

lab tests of trachoma

NAATs PCR enzyme immunoassay fluorescein labeled monoclonal AB assay

diagnostic smear of trachoma

conjunctivital smear

trachoma TTT

infants--->tetracycline, erythromycin cream (10-14d) adults---->oral tetracycline,doxycycline, erythromycin (3-6w) surgical correction of eyelid deformities

aerobic gram - rods non lactose fermenting on MacConkey Pyocyanin pigment produced oxidase positive

P.aeruginosa

P.aeruginosa virulence factors (3)

exotoxin A pili antiphagocytic capsule

exotoxin A of P.aeruginosa inactivates

elongation factor-2

Protein A of staph.aureus binds to

Fc region of IgG to (-) opsonization + protects from phagocytosis

HSV-1 reactivation in ophthalmic division of trigeminal ganglia causes

dendritic ulcer (corneal lesion) severe keratoconjunctivitis

recurrent keratitis may lead to

permanent corneal scarring & opacity

epidemic keratoconjunctivitis is caused by

adenovirus serotypes 8 & 19

gritty feeling in eye sharp pain conjunctivitis sensitivity to light opaque corneal lesions small vesicles on conjunctiva are symptoms of

keratoconjunctivitis

keratoconjunctivitis TTT

topical+ oral acyclovir HSV oral acyclovir herpes zoster ophthalmicus

specimens used in diagnosis of eye infections

conjunctival swab corneal scraping

eye infections culture

blood & chocolate agar 5-10% CO2 gram stained films PCR for viral infections

infections of deep layers of eyes are caused by (5)

P.aeruginosa Rubella CMV West nile fever rift valley fever

Rubella & CMV causes

cataract microphthalmia severe chorioretinitis in AIDS