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Flashcards in Acute corneal pathology - keratitis Deck (50)
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1

list 5 things that you need to consider about a patient with a corneal disease

- Symptoms
- Careful history
- Anatomy of the cornea
- External factors
- Internal factors

Don’t consider the cornea in isolation

2

which 2 types of keratitis are there

- Infective
- Non-infective (‘arc’ eye, dry eye, toxins)

3

what causes recurrent corneal erosion syndrome

The epithelium is the fastest part of the body that repairs, but if the patient had a bad abrasion then it will keep coming back as the cornea never heals properly

4

what role does flourescein have in assessing dryness on the cornea

it works as an indicator and grows and shows the defects on the epithelial surface

5

what is rose bengal used to stain

degenerate cells

6

what is another word for dry eye
and list 4 things that can cause it

- superficial punctate keratitis

- UV exposure
- eye lid malposition
- Bell's palsy
- post laser refractive surgery

7

list 6 common ocular infections that can be transmitted by clinical contact

- viral (intracellular organisms)
- chlamydial (half way between virus and bacteria)
- bacterial
- fungal
- acanthamoebic
- parasitic

8

which 2 serotypes is adeno virus conjunctivitis from

8 and 19

9

what is it called when the cornea is involved in adenovirus
what is the key feature of an adenovirus

- adenovirus keratoconjunctivitis

key feature
- follicles in the eyelid, when pull down or evert the top eyelid as they line the conjunctiva of the lids

10

what is the signs and symptoms of a adenovirus keratoconjunctivitis

will be in both eyes
- red
- watery
- pain
- cornea has white fluffy infiltrates
- follicles
- pseudomembrane

11

in adenovirus keratoconjunctivitis,
where do the epidemic outbreaks occur
how long is the incubation
how long is it communicable for
where is its portal of entry
what are it's risk factors
what is it associated with
what may the keratitis affect and how long can it take to resolve

- epidemic outbreaks in closed communities
(EKC)
- incubation: 5-12 days
- communicable: 10-14 days
- portal of entry: conjunctiva
- risk factors: crowding, ocular trauma
- associated with cold or influenza-like illness
(PCF)
- keratitis/adeno spots in cornea may affect vision and take weeks or
months to resolve

12

what forms the follicles in an adenovirus and what do they look like

areas of lymphocytes/white blood cells, that accumulate to try and fight off the virus

white raised round areas

13

what is a pseudo membrane and where is it found (seen in adenovirus)

a fibrous sheet underneath the top lid which is very painful

14

what is the management of adenovirus keratoconjunctivitis

- avoidance of cross-infection (separate towels etc)
- no effective anti-viral
- topical antibiotic to prevent secondary bacterial infection (to stop getting bacterial conjunctivitis on top, use a broad spectrum antibiotic)
- topical steroid - severe conjunctivitis with pseudomembrane
- topical steroid if keratitis is painful or affects vision (to help with comfort, but does not fight the infection)

15

in how many patients is herpes simplex virus present in and in what form
in how many people have a recurrent clinical infection

- latent in 56-90% of the world’s population
- one third of all people have recurrent clinical infection

16

what is the 2 types of herpes simplex virus

- HSV-1 (saliva transmission - children and adolescents)

- HSV-2 (sexual transmission or via birth canal)
• in USA this sub-type has increased by 30% in 20
years!
• likely to be the result of changed patterns of sexual
behaviour)

17

in the latency period, where is HSV-1 located and where is HSV-2 located
what cannot be done about them

HSV-1: trigeminal ganglion (5th cranial
nerve)
- HSV-2: sacral nerve root ganglia (S2-S5)

- cannot be eradicated
- no satisfactory vaccine exists (to prevent primary infection)

18

list 6 things that can cause the reactivation of a latent herpes simplex virus

- fever
- trauma
- emotional stress
- sunlight
- menstruation
- laser refractive surgery

19

describe how a patient with HSV-1 can get a cold sore

HSV-1 cold sores is not contagious, but is always dormant in the body
these viruses live in the ganglion and when you get a cold, the virus has a chance to attack when the body is under stress
the virus comes down the ganglia and down the nerves and ends up on the lips

20

what type of infection is HSV type 1 virus
and give 4 signs of HSV-1

- primary infection

- blepharo-conjunctivitis
- cold sores
- follicular conjunctivitis
- pre-auricular nodes (PAN) - swollen lymph nodes infront of the ears

21

what type of infection is Herpes simplex keratitis
and list 4 signs seen

- Secondary infection (from flu or stress)


- Dendritic lesions (in epithelium)
- Disciform keratitis (stroma and endothelium involved)
- Anterior stromal scars
- Geographic lesions (ulcers)

22

how can dendritic ulcers be see on the eye of someone with herpes simplex keratitis

flourescein

23

what happens if a dendritic ulcer is not managed in herpes simplex keratitis

it turns into a geographic ulcer

24

what is a disciform keratitis seen i herpes simplex keratitis

- wrinkles/folds seen in descents membrane
- stroma and endothelium can get involved and px can get uveitis
- when theres endothelial damage and the stroma gets swollen and damaged = tear film looks rough

25

what is the appearance of extensive HSV scarring and why is it difficult to treat

- new blood vessels, superficial and deep coming in (scarring from a dendritic ulcer)
- very difficult to treat due to the BVs, so can't do corneal transplant and the surface is also rough

26

what is herpes zoster virus know as

what is it caused by
in how much % of the population is it present in

where is the VZV vaccination available and how does it work and how much efficacy does it have

where does it lie when its dormant

- shingles

- caused by Varicella Zoster virus (“chicken-pox”)
- present in 20% of the population

- VZV vaccination available
routine only in Germany
- aim is to infect children with a live attenuated VZV to
give immunity through a sub-clinical infection
- disease prevention with 85-95% efficacy

- like Herpes Simplex virus, lies dormant in nerve roots
- posterior (dorsal) spinal and cranial sensory ganglia
- chicken pox virus also lives in the ganglia, especially sensory ganglia e.g. in CN5 trigeminal nerve. pairs of ganglia down spinal chord and when supplies the thorax and abdomen is in strips and the pair of nerves supplies sensation to the skin, so the attack of HSV later in life just affects that particular nerve, so px will have a single strip of rash which is painful and sore

27

what is herpes zoster keratitis an involvement of and what does it produce
how many % has corneal involvement
name 2 signs

- involvement of ophthalmic division of
trigeminal nerve produces typical (unilateral)
rash over skin of face and scalp

- corneal involvement in 50% (nasociliary branch of V)

- ‘pseudo-dendrites’ of mucus
disciform keratitis similar to HSK
vascularisation with calcium deposition
chronic ulceration / melting
associated with uveitis

28

what can happen once a patient has had shingles/herpes zoster keratitis and is recovered and what is this called

px can still get pain, even when virus has gone

called post hepatic neuralgia (serious nerve pain)

29

which 3 eye conditions can chlamydial infections cause

- Adult inclusion conjunctivitis
- Neonatal conjunctivitis
- Trachoma

30

which subgroup and serotypes is adult inclusion conjunctivitis (chlamydial infection) from

how is it caught

what 2 ocular signs is seen with this

- sub group A
- serotypes D-K

- sexually transmitted (also ophthalmia neonatorum from birth canal)

- follicular conjunctivitis (follicles in upper and lower fornix)
- punctate keratitis