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Flashcards in EYE infections Deck (77)
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1
Q

conjuntiva NF orgs

A

Staph epidermis, diphtheroids, Propionibacterium acnes

2
Q

cause of conj. inflamm

A

chem irritants, allergies, inf. agents, diminution of tears, (keratoconj. sicca)

3
Q

host defense mechs against conjunct.

A

mech. action of blinking
tears: lysozyme, sec. IgA, host-der. antimicrobial peps, etc
conj. : lympos, plasma cells, neutros, mast cells
int. eye protected by eyelids, conj., sclera, cornea (sterol and imm. privileged)

4
Q

trauma or disease cause inflammation

A

(papillae, follicles present)

extravasation of neutros, macros, lymphos from conj. vasc into tears

5
Q

follicles are..

A

focal lymp. aggr. assoc. w. viral/chlamydial infection (1-2mm) translucent elevations on lower conjunctiva

6
Q

papillae are..

A

mult. minute, opaque elevations on conjunctiva, non-specific but typ. assoc w/ EC bac disease

7
Q

conjun. (bac and viral) s/s

A

itching, burning, discharge, preauricular lymphaden. +/-, typ. unilat, most cases benign, self-limiting

8
Q

conj. discharge

A

serour fluid OR purulent (PMN or moncytic) OR mucopuruleng (exc. PMN) (PMS: bac, Monocytes: viral/fungal)
-if discharge, clears w/ blinking

9
Q

conj. complications

A

medical emergency req. imm. tx bc indicated inf. has spread to cornea (keratitis): vision impairment has begun

10
Q

symp. of keratitis

A

eye pain, photophobia, vis. impairment

11
Q

ddx conjunc.

A

conjunctivokeratitis, blepharitis, corneal abrasion, FB, other cause of subconjunc hemorrhage (cough/V), iritis, glaucoma, chem burn, scleritis

12
Q
bac conjunc (acute purulent/mucopurulent) conj. 
most common orgs
A

*Staphylococcus aureus (G+ cocci)
*Streptococci (G+cocci) S. pneumoniae, S. pyogenes (Staph & Strep most common in adults/ww)
H. flu (giogroup aegyptius (G- rod)
Moraxella catarrhalis (G- cocci)
Neisseria gonorrhoeae and Chlamydia spp.

13
Q

bac conj. common orgs for age group

A

neonates: GC, chlamydia
up to school age: 2x more likely bac>virus
>=school age: viral/allergic (20%: adenovirus) epidemic keratoconjunc. more common in adolescents, adults

14
Q

pink eye

A

acute contagious conjunct. w/ sub conj. hemorrhage (pink sclera)
most common: NTHi (aegyptius), Streptococcus pneumoniae (less moraxella spp., Pseudomonas aeruginosa)
*most common form of conj. in children
symps: gen conj. s/s, rapid, unilat lid edema, poss. contralat inv. 1-2 days, purulent neutro discharge, lid margin crusting, subconj hemorrhage (pink sclera), abs. of pre auricular lymphaden.

15
Q

conjunc.-OM syndrome

A

orgs: NTHi, S. pneumo, Moraxella catarrhalis

infants, young kids (spreads btw siblings)

16
Q

conjunc-OM dx

A

clin. obsv. lab confim: conjunc swab–>smear–>Gs, Cx, Abx sens. testing

17
Q

conjunc-OM tx

A

benign and self-lim: 10-14 d, *EXCEPT S. aureus origin
topical abx w/ br-spec abx for 7-10 days: trimethoprim-polymixin, fluoroquinolone
*milder inf. will resolve w/out tx

18
Q

Infectious Hyperacute Mucopurulent Conjunctivitis is called this in the neonate

A

Ophthalmia neonatorum (1st 28 days) contam of eyes thru birth canal

19
Q

IHM conjun org: Neisseria gonorrhoeae

A

(G- cocci), major cause of STD, affects 50% of all infants born to gon-inf. moms, earlier (d 2-5 of life) than C. trachomatis
rapid, fulminante progression w. copious mucopurulent exudate, erythema, eyelid/conjunc edema, freq. bilat
rapidly destr. inf–>ulc, perf, blindness even in abs. of any corneal trauma/abrasio

20
Q

inf. hyperacute mucopur. conjunc. (N. gon) tx

A
  • Medical emergency!* imm. tx and consult w. ophthalmologist (unlike Chlamydial ophthalmia neonatorum: tx but not emerg.)
  • tx imm. s. syst. abx (ceftriaxone or other 3rd gen cephs/fluoroquinolones (ciprofloxacin), freq. saline eyewash w/ abx, delayed tx (even1-2 d) can result in blindness!
21
Q

inf. hypacute mucpur conjunc (Chlamydia trachomatis) (serotypes D-K)

A

Inclusion conjunct of newborn, G- cell wall architecture (can’t see w. Gs), an obli. IC pathogen

  • affects many infants born to moms inf. w/ chlamydial cervicitis
  • appears later: day 5-10 of life
  • less purulent, more serous discharge, less progressive
  • sight not threatened and dis. is self-limiting
22
Q

IHM conjunc (C. trachomatis) tx

A

oral and topical erythromycin

23
Q

Herpes classic triad (conjunc)

A

skin, eye, mouth (SEM): inclusion keratoconjunctivitis of newborn
obl. IC pathogen: HHV-2, affects some infants born to inf./shedding moms
appears even later! 9-10d of life) than N. ton and C. trach ocular disease
tx: acyclovir or other antiviral

24
Q

other causes of inf hypacute mucpur conjunc

A

vag flora: Staph, Strep, some G- rods

25
Q

symptoms of bacterial inf. IHM conjunc

A

unilat or bilate erythema, sev. eyelid edema, conjunc. edema, profuse exudate w. marked purulence

26
Q

Inf. hypacute mucopurulent conjunc dx

A

s/s, start emp. tx imm, Gs, Giemsa stain, DFA stain, Cx from conjunctival scrapings or swabs (also from mom)

27
Q

Gs and Cx + for N. gonorrhoeae reveal

A

G- diplococci w/in cytoplasm of PMNs on Gs of conjunct. on smears and scrapings from symp. child
*if negative, may indicate chlamydial etiol. (not routinely Cs in labs, not vis. on Gs)

28
Q

Giemsa or DFA stain of conjunc material that reveal intracytoplasmic inclusions is positive for

A

chlamydia (also if chlamydia Ag present)

29
Q

IHM conjunc. can have coinfection w/

A

N. gon and C. trach (50% of inf. women)

30
Q

prev. of ophthalmia neonatorum

A

Crede procedure: silver nitrate (1%) for N. gon + abx eye drops (eryth, doxy, tetra for both G/C) –>causes chem conjunct. 24-48 hrs, prev. blindness

31
Q

Inclusion conjunctivitis (IC)

A

any conjunct. caused by ob IC pathogen

-presence of IC (cyto or nuc) inclusions which is a cytopathic effect induced by the pathogen

32
Q

IC etiol.

A

ob IC pathogen: Chlamydia trachomatitis or any viral conjunc. agent

33
Q

IC patho

A

lysis and/or necrosis of epi cells–>inflamm resp. (symptoms)
typ. follicular–>cause irritation and FB sensation
dx: (cytoplasmic inclusions obs. on microscopic findings. of conjunct scrapings, or on Giemsa stains, DFA/FAT for chlamydia
if viral: IN inclusions on Tzanck stained scrapings/smears for herpes virus)

34
Q

Chlamydia trachomatis(G-) conjunctivitis

A

causes IC at any age–>end stage in adult is trachoma (*leading cause of prev. inf. blindness ww)

35
Q

trachoma

A

keratoconjunctivitis which may result in partial/total vision loss

36
Q

trachoma org.

A

C. trachomatis (serovars A thru C)

37
Q

trachoma incidence

A

poverty/unsanitary: underdev. nations: Mid East, SE Asia, Africa, SW US (immig. pops and indian reserv)
not transmissible h to h, but by low sanitation (lack of clean H2O); via flies, fomites, finger-eye inoculation
*inf. kids are source/reservoir
incidence of active dis. dec w/ age

38
Q

trachoma immunology

A

“double-edged sword” limits replication of pathogen & induces patho changes to eye
some protect. immun. (dis. of childhood, only adults have scarring)

39
Q

trachoma disease course

A

slowww (years); begins as acute inclusion conjunct., rep. exposure to Chlamydial Ags–>intense chr. inflamm. resp–>scarring of inner eyelid–>retraction of tarsal plate–>inverting the eyelid: entropion–>inverted eyelashes (trichaisis) constantly abrade cornea–>corneal opacity/scarring

40
Q

trachoma dx

A

clin. obs in endemic area
Giemsa, FAT: IC inclusions, low sens.
PCR is most sens., rarely done

41
Q

trachoma tx/pxx

A
no vaccine!
WHO imp. SAFE strategy: 
Surgery
Abx
Face/hand washing
Environ. change (inc. clean water, better sanitation, education)
42
Q

viral conjunctivitis (epidemic, inclusion conjunc)

A

adenovirus
coxsackie virus/ enterovirus
HSV 1, VZV, measles virus

43
Q

viral conjunc. incidence

A

more common than bac! highly inf.–>via ocular sec. eye-hand-eye

  • adenovirus most common
  • prim. HSV-1 most common viral IC in kids
44
Q

viral IC patho/s/s

A

transient, self-lim
gen symps of conjunct. w/ mild tearing/itching
thin watery discharge/exudate bearing monocytes (NOT purulent), + follicles, pre auricular lymphaden.

45
Q

viral IC: pharyngeal conjunctival fever

A

transient, self-lim (2-4 wks)
adenovirus (3,4,7)
contam. swimming pools! so kids, y. aduls in summer (or lakes/ponds)
-kids contagious 1st 2 w

46
Q

pharyngeal conjunctival fever triad

A

fever, pharyngitis, IC symps

47
Q

pharyngeal conj. fever dx, tx, ppx

A

clin obs. epid. consider
no tx, resolves about 2 wks
ppx: contagious 1st 2 wks so keep out of school

48
Q

epidemic Keratoconjunctivitis (“shipyard eye”)

A

adenovirus (8,19,37,11)

highly contagious, spread by close contact, sec. fomites

49
Q

epidemic Keratoconjunctivitis symps

A

PCF + mild irritaiton and sev. photophob. (10-14 d post onset), painful cent. located corneal ulcer (keratoconj. from imm. resp. to inf.) may persist for mos.

50
Q

epidemic Keratoconjunctivitis dx tx ppx

A

dx: clin obs, contact w/ case
tx: supportive/palliative, rem. of membranes and pseudo mem along w/ top steroids (imp. comfort)
ppx: isolate inf. pt (10-14 d) educate

51
Q

acute epidemic hemorrhagic conjunctivitis (AEHC)

A

highly contagious, self-lim,

crowding, poor hygiene

52
Q

acute epidemic hemorrhagic conjunctivitis viruses

A

Coxsackie virus (A24)
enterovirus 70
adenovirus (11)

53
Q

symps of AEHC

A

bilat, sudden, photophob, exc. tearing (epiphora), eye irritiation/FB sens, eyelid edema, erythema, conj. hem, pink sclera, sm. superfic. corneal ulcers, superfic. punctate keratitis
short (4-5d) duration, spont. resolution

54
Q

tx, ppx of viral IC (all)

A

tx symptomatically, topical corticosteriods, NO topical abx unless discharge becomes purulent/mucopurulent (second. bac inf)
ppx: know infectious period, keep home, approp. personal hygiene

55
Q

Keratitis (corneal inflammation)

A

corneal inflammation–>corneal ulceration w/in 24 hours! eye emergency–>risk of rapid vision loss

56
Q

keratitis bac

A

Staph (G+coc) Strep (G+coc) Listeria (G+rod) Neisseria (G-coc) anaerobes, GNRs, Pseudomonas aeruginosa (causes corneal inf. w/ soft contact lens use

57
Q

fungal etiol. of keratitis

A

less common, but happens w/ eye trauma

58
Q

protozoan etiol of keratitis

A

Amoeba: Acanthamoeba sp. (rare: tap water use for contacts)

59
Q

viral etiol. of keratitis

A

typ. adults
immune suppression is key prec. factor, recur. common
-HSV-1: leading cause blindness in dev./industr. countries (vs C. trach in underdev. countries)
-50-500k cases in US/yr, 1000s corneal trans.
-VZV keratitis involves a periorbital lesion
tx (both HSV-1 and VZV keratitis) w/ prol. combo topical acyclovir and corticosteroids

60
Q

keratitis path for non-viral agents

A

brkdwn in corneal epi–>invasion of corneal stroma by WBC (immpath) and bac (toxin-prod, i.e. proteases)–>some corneal scarring/opacification from inflamm. (even if tx)

61
Q

keratitis path for viruses

A

viral repl–>cytolysis of corneal cells (dendritic figures: clinical sign)
-inf. is reactiv. of latent inf. so no breach in corneal epi layer req (virus inf. acq. early in life, remains latent in trigeminal/cervical ganglia–>triggered by environ. or sec. imm supprs–>migrates to cornea, can be shed (even when no symps)

62
Q

symps of keratitis

A

unilat red eye, mod-sec ocular pain, photophob, serous discharge, dec. vision, loss of corneal luster/appearance, viral agents cause dendritic bodies/lesions (fluorescein dye, slit lamp)
VZV keratitis: if involves periorbital skin, many dev. ocular complications

63
Q

keratitis dx

A

clin. findings, labs: NV: Gs, Cx, sens
viral: DFA, Cx, PCR
ophthalmology consult for HSV Ker. and VAV ker. to ID virus and det. epi or stromal forms (dendritic figures)

64
Q

keratitis tx

A

non-viral agents: antimicr. tx to avoid perf, ulc, blindness: FQ eye drops (Ciloxan, Ocuflox)
HSV K: depends on K form
VZV keratitis: oral acyclovir (3 days)

65
Q

retinitis

A

CMV retinitis HHV 5

66
Q

retinitis most common viral sight/life threatening opp. inf. in

A

AIDS pts; poor px

67
Q

retinitis path

A

recrudescence of latent CMV inv (waning CMI)

68
Q

retinitis symps

A

unilateral–>bilat vision loss due to eye lesions–>visual field loss and dec. visual acuity

69
Q

retinitis dx

A
red patches (hemorrhage) and white (necrosis, edema) over lg portions of retina
vitreous clear and inflamm-free
70
Q

retinitis tx

A

ganciclovier, foscarnet, cidofovir (IV, intravitreally, both)

71
Q

this org. causes retinitis (not as common as viral CMV cause)

A
Tosoplasma gondii (protozoan, EUK)
path: recrudescence of latent T. gondii inv (waning CMI)
72
Q

other causes of retinitis

A

“salt and pepper lesions” of congenital rubella (German measles)
*HSV (prim and rec)
*VZV (prim and rec**)
*dis. in bot immcomp and CMI comp, poor ps despite high does IV acyclovir
Roth spots of infectious endocarditis

73
Q

River blindness org

A

(Onchocerciasis)

parasitic worm: Onchocerca volvulus (helminth, tissue round worm, filarial nematode)

74
Q

River blindness cycle

A

transmit. thru bites- blackflies (Simulium)
* *2nd leading cause of blindness ww! (after trachoma)
- microfilariae found in peripheral blood, urine, sputum, mostly skins and lymph. of CT (2y lifespan)

75
Q

River blindness path

A

systemic, derm, ocular inf
symps caused by body’s resp to dead/dying larvae (rel. Wobachia bac)
-skin inflammation: itchy and damaging
-eye inflammation: rev. lesions on cornea–>if no tx, perm. clouding–>blindness
also optic nerve inflamm.–>vision loss (perish)–>blindness

76
Q

River blindness s/s

A

itchy skin rashes: “leopard skin”, thinning: “cigarette-paper” “hanging groin”
nodules under skin
vision changes: loss of peri vision/blindness
occ. non painful swelling of lymph glands

77
Q

River blindness tx

A

IVERMECTIN (ev. 6 mos as long as eye/skin inf)

**but make sure not Loa loa!!: sev. SEs (encephalopathy) to ivermectin*

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