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Flashcards in EYE infections Deck (77):
1

conjuntiva NF orgs

Staph epidermis, diphtheroids, Propionibacterium acnes

2

cause of conj. inflamm

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

3

host defense mechs against conjunct.

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

trauma or disease cause inflammation

(papillae, follicles present)
extravasation of neutros, macros, lymphos from conj. vasc into tears

5

follicles are..

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

6

papillae are..

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

7

conjun. (bac and viral) s/s

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

8

conj. discharge

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

9

conj. complications

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

10

symp. of keratitis

eye pain, photophobia, vis. impairment

11

ddx conjunc.

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

12

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

*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

bac conj. common orgs for age group

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

pink eye

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

conjunc.-OM syndrome

orgs: NTHi, S. pneumo, Moraxella catarrhalis
infants, young kids (spreads btw siblings)

16

conjunc-OM dx

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

17

conjunc-OM tx

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

Infectious Hyperacute Mucopurulent Conjunctivitis is called this in the neonate

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

19

IHM conjun org: Neisseria gonorrhoeae

(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

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

*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

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

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

IHM conjunc (C. trachomatis) tx

oral and topical erythromycin

23

Herpes classic triad (conjunc)

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

other causes of inf hypacute mucpur conjunc

vag flora: Staph, Strep, some G- rods

25

symptoms of bacterial inf. IHM conjunc

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

26

Inf. hypacute mucopurulent conjunc dx

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

27

Gs and Cx + for N. gonorrhoeae reveal

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

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

chlamydia (also if chlamydia Ag present)

29

IHM conjunc. can have coinfection w/

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

30

prev. of ophthalmia neonatorum

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

Inclusion conjunctivitis (IC)

any conjunct. caused by ob IC pathogen
-presence of IC (cyto or nuc) inclusions which is a cytopathic effect induced by the pathogen

32

IC etiol.

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

33

IC patho

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

Chlamydia trachomatis(G-) conjunctivitis

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

35

trachoma

keratoconjunctivitis which may result in partial/total vision loss

36

trachoma org.

C. trachomatis (serovars A thru C)

37

trachoma incidence

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

trachoma immunology

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

39

trachoma disease course

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

trachoma dx

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

41

trachoma tx/pxx

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

42

viral conjunctivitis (epidemic, inclusion conjunc)

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

43

viral conjunc. incidence

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

viral IC patho/s/s

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

45

viral IC: pharyngeal conjunctival fever

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

pharyngeal conjunctival fever triad

fever, pharyngitis, IC symps

47

pharyngeal conj. fever dx, tx, ppx

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

48

epidemic Keratoconjunctivitis ("shipyard eye")

adenovirus (8,19,37,11)
highly contagious, spread by close contact, sec. fomites

49

epidemic Keratoconjunctivitis symps

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

epidemic Keratoconjunctivitis dx tx ppx

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

acute epidemic hemorrhagic conjunctivitis (AEHC)

highly contagious, self-lim,
crowding, poor hygiene

52

acute epidemic hemorrhagic conjunctivitis viruses

Coxsackie virus (A24)
enterovirus 70
adenovirus (11)

53

symps of AEHC

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

tx, ppx of viral IC (all)

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

Keratitis (corneal inflammation)

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

56

keratitis bac

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

fungal etiol. of keratitis

less common, but happens w/ eye trauma

58

protozoan etiol of keratitis

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

59

viral etiol. of keratitis

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

keratitis path for non-viral agents

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

keratitis path for viruses

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

symps of keratitis

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

keratitis dx

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

keratitis tx

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

retinitis

CMV retinitis HHV 5

66

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

AIDS pts; poor px

67

retinitis path

recrudescence of latent CMV inv (waning CMI)

68

retinitis symps

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

69

retinitis dx

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

70

retinitis tx

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

71

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

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

72

other causes of retinitis

"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

River blindness org

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

74

River blindness cycle

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

River blindness path

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

River blindness s/s

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

River blindness tx

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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