Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

(2) Introductory ocular disease > Allergic eye disease > Flashcards

Allergic eye disease Flashcards

1
Q

What is the immune system and how can it dysfunction?

A

• Protection from invading micro-organisms and other material
• Detection triggers inflammation

• Dysfunction:
- Under-active: immunodeficiency, vulnerable to infection
- Over-active: inappropriate inflammatory response
- Allergies: unnecessary inflammation to harmless antigen
what do you mean aaa
pollen-allergy/
Allergies: unnecessary inflammation to harmless antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is Hypersensitivity and what are the four types?

A

Exaggerated response to innocuous antigen to which body has already been exposed

• Type 1: Acute/Anaphylactic
• Type 2: Cytotoxic
• Type 3: Immune complex
• Type 4: Cell mediated (delayed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the Types associated with allergic eye disease, and their subtypes?

A

• Type 1 Hypersensitivity
- Seasonal and Perennial Allergic Conjunctivitis
- Vernal Keratoconjunctivitis
- Atopic Keratoconjunctivitis
- Giant Papillary Conjunctivitis (CLAP-C)

• Type 4 Hypersensitivity
- Additional inflammatory component

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe seasonal and perennial allergic conjunctivitis

A

• Most common type
• Type 1 hypersensitivity

• Seasonal (SAC): Ocular form of hayfever, antigen = grass/tree pollen
- Seasonal variation: worst in summer

• Perennial (PAC): Non-seasonal antigen, antigens = dust, house dust mites, animal hair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe Atopy:

A

• Atopy: Genetic predisposition to Type 1 Hypersensitivity
•Secrete more IgE antibodies than controls
• 10-40% of population
•Associated allergies (food, medication, cosmetics)

• Eczema, hayfever, asthma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Symptoms of Seasonal and perennial allergic conjunctivitis

A

• Time cause (differentiate seasonal, chronic of perennial)

• Itching/itchiness
- Key symptom, action of histamine

• Bilateral
- Airborn antigen

• Redness
- Lids and conjunctiva

• Lacrimation
- Immune system flushing eyes

• Sneezing/nasal discharge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Signs of Seasonal and perennial allergic conjunctivitis

A

• Hyperaemia
- Conjunctiva/lids

• Eyelid Oedema
- Inflammation cause increase in permeability

• Conjunctival chemosis
- Oedema causes fluid filled conjunctiva

• Papillae
- Raised nodules of palpebral conjunctiva, cobblestone appearance (accumulation of inflammatory cells)

• Palpebral roughness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Management of seasonal and perennial allergic conjunctivitis: Advice

A

• Managed in primary care, no need for referral

• Environment
- identify cause, prevent exposure
- Tight fitting sunglasses
• Discourage eye rubbing

• Cold compresses
- Promotes vasoconstriction, reduces blood flow and histamine , relieves itching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Management of seasonal and perennial allergic conjunctivitis: Pharmacological

A

• Artificial tears/lubricants
- Dilutes/removes antigen

• Antihistamines
- Antagonist of antihistamine
> Systemic: sell/supply to px, can buy directly with no Rx
> Topical: IP optom prescribe only, Rx needed

• Mast cell stabilisers
- Stops mast cells degranulating
- Best used as prophylactic, long term management (2 weeks in advance)
- No need for Rx

• NSAIDs
- IP only
- Inhibit synthesis of prostaglandins
- rapid control of inflammation
- initial management

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Management of seasonal and perennial allergic conjunctivitis: Entry levels

A

• Advice on environment
• Cold compresses
• Eyewashes, artificial tears, ocular lubricants
• Systemic antihistamines- initially
• Mast cell stabilisers- longer term

• More Severe Cases-Referral
> Topical (eye-drop) antihistamines
> Topical NSAIDs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe Vernal Keratoconjunctivitis

A

• Less common, more severe
• Recurrent and sight-threatening
• Type 1 Hypersensitivity (Plus Type 4)
• Genetic predisposition: Raised levels of IgE in tear film, mast cells in conjunctiva
• Young children (8-12 years old)
• M:F = 3-4: 1
•More common in warm, dry environments (Africa, India, Mediterranean region)
• Atopic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Vernal Keratoconjunctivitis symptoms

A

•Bilateral, but perhaps asymmetrical
• Year-round, but worst in Spring-Summer
• Extreme itching
• Redness
• Lacrimation
• White, mucoid, stringy discharge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Vernal Keratoconjunctivitis symptoms; corneal

A

• Blurred vision
- Corneal damage disrupts transmission and refraction

• Pain
- Cornea densely packed with sensory nerves

• Photophobia
- Irritation of sensory nerves (Cranial nerve 5, trigeminal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Vernal Keratoconjunctivitis Signs:
Palpebral conjunctiva

A

• Hyperaemia of conjunctiva and eyelids
• Giant (>1mm) papillary reaction
•Collections of inflammatory cells
• Increased blood vessel permeability
•Most intense: superior palpebral conjunctiva
•Always evert upper eyelid
• Cobblestone appearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Vernal Keratoconjunctivitis Signs:
Limbus

A

• Limbal papillae
•Raised, gelatinous lumps
• Accumulations of inflammatory cells
• White dots at apex: horner-trantas dots
- Focal points of epithelial and inflammatory cells
• Limbal hyperaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Vernal Keratoconjunctivitis Signs:
Cornea (beginning)

A

• Papillae release chemicals which are toxic to corneal epithelium
• Loss of epithelial cells
• Detect with fluorescein
• Lost epithelial cell- small gap/depression
• Fills with fluorescein - more concentrated dye
• Brighter fluorescence - small, bright dots
• Superficial Punctate Keratitis (SPK)

17
Q

Vernal Keratoconjunctivitis Signs:
Cornea (Progressing)

A

• As severity increases, more epithelial cells are lost
• Confluent, dense patches of epithelial loss
• Macro-erosion
• Epithelium normally repairs within 48 hours..
• Ongoing inflammation- no opportunity for recovery
• Persistent corneal damage
• Blurred vision, pain and photophobia

18
Q

Vernal Keratoconjunctivitis Signs:
Cornea (Severe)

A

• If untreated, corneal damage intensifies
• Toxicity effect + Mechanical damage from lids
• Plaque/Shield ulcer = non-healing epithelium
• Appearance of cloudy/white regions
• Sub-epithelial scarring

19
Q

Vernal Keratoconjunctivitis: Management

A

• Cold compresses
• Mast cell stabilisers

• Urgent referral (telephone call): Limbal or corneal involvement
• Routine referral : No limbal/corneal involvement, with symptoms controlled by treatment with mast cell stabilisers

• Topical steroid eye drops
- Powerful anti-inflammatory, inhibit synthesis of chemical mediators of inflammation
- Stronger than NSAIDS
- Prednisolone acetate (1%)

20
Q

Describe Atopic keratoconjunctivitis

A

• Severe and chronic allergic eye disease
• Risk of significant corneal damage- sight-threatening
• Type 1 Hypersensitivity (Plus Type 4)
• Sensitive to many airborne antigens
• Young adults (30-50 years old)
• Higher incidence amongst males
• Follow-on from VKC
• Atopic

21
Q

Atopic keratoconjunctivitis: Symptoms

A

• Bilateral
• Itchy eyes
• Redness
• Lacrimation
• White, mucoid, stringy discharge
• Symptoms present year round

Corneal involvement:
• Pain
• Photophobia
• Blurred vision

22
Q

Atopic keratoconjunctivitis: Signs
(Lids)

A

• Inflamed
• Hyperaemia - Vasodilation
• Thickened- blood vessel permability
• Skin - dry and scaly
• Cracks, scratches and fissures
> Exacerbated by eye rubbing

23
Q

Atopic keratoconjunctivitis: Signs
(Conjunctiva)

A

• Inflamed
• Hyperaemia- vasodilation
• Papillary reaction- smaller than VKC

• Chronic inflammation:
- Conjunctival scarring
- White, featureless appearance
- Symblepharon

24
Q

Atopic keratoconjunctivitis: Signs
(Cornea)

A

• Superficial punctate keratitis
• Macro-erosion
• Plaque/Shield ulcer
• Sub-epithelial scarring
• Neovascularisation

25
Q

Atopic keratoconjunctivitis: Management

A

• Corneal involvement: urgent referral (telephone) to ophthalmologist
• Mild cases: Routine referral to opthalmologist

> Cold compresses
Mast cell stabilisers (e.g. sodium cromoglicate)
Systemic antihistamines (e.g. cetirizine oral tablets)

• IP Optometrists: Topical antihistamine (e.g.olopatadine)
• Ophthalmologists: Topical steroids (e.g. prednisolone)

26
Q

Describe Giant Papillary Conjunctivitis (GPC)

A

• Most often complication of CL wear
•Contact Lens Associated Papillary Conjunctivitis (CLAP-C)
• Type 1 and Type 4 Hypersensitivity reaction
• Mechanical component- micro-trauma
•Exacerbated by lens deposits (inadequate cleaning)
•Soft more than Rigid CLs
• Rare causes include prosthetics, sutures and buckles (surgery)

27
Q

Describe Giant Papillary Conjunctivitis (GPC): Symptoms

A

• Bilateral
• Itchy, irritated eyes
- May increase after lens removal
• Increased contact lens movement
• Reduced tolerance to contact lenses
• White, mucoid, stringy discharge

28
Q

Describe Giant Papillary Conjunctivitis (GPC): Signs

A

• Superior palpebral conjunctiva
• Need to evert lids at every contact lens assessment
• Hyperaemia (vasodilation)
• Papillary conjunctivitis (collections of inflammatory cells)
• Mild- irregular light reflection (difficult to identify individual papillae’
• Moderate- larger, more distinct papillae
• Severe- Giant papillary conjunctivitis (>1mm in diameter)

29
Q

Describe Giant Papillary Conjunctivitis (GPC): Management

A

• Remove mechanical trigger to inflammation:
- Cease lens wear for an initial period to allow resolution of papillary response
- Improving cleaning regimen
- Replacing contact lenses more frequently (e.g. monthly to daily disposables)
- Reduce wearing time

• Surgical artefacts: referral to ophthalmologist
> Mast cell stabilisers (e.g. sodium cromoglicate)
Topical antihistamines (e.g. olopatadine) IP Optom only

(2) Introductory ocular disease (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions