wk6: AED - Allergy 2 [DG] Flashcards
List the symptoms of VKC (8)
intense itching/burning watery photophobia FB sensation puffy lids mucoid discharge blurred vision eye rubbing
List the signs of VKC (7)
symptoms may worsen in spring + early summer
type 1 hypersensitivity
uncommon, bilateral, males>females
most common age @5-25yrs
most sufferers atopic (people with other allergies) or have family hx of atopy
usually affects superior tarsal conjunctiva but may affect limbal area (or could affect both)
List the clinical features of VKC (8)
bilateral
conjunctival hyperaemia + chemosis
large palpebral papillae (up to 5mm)
stringy mucus dicharge (may sit b/w papillae)
ptosis
Corneal changes: SPK, shield ulcers, subepithelial scarring, eosinophil plaques
Limbus: limbitis with limbal papillae + Horner-Trantas’ dots, and pseudogerontoxon
How does VKC present in the cornea? (4)
SPK, shield ulcers, subepithelial scarring, eosinophil plaques
How does VKC present at the limbus? (3)
limbitis with limbal papillae + Horner-Trantas’ dots, and pseudogerontoxon in area of previously inflamed limbus
What DDx exist for VKC? (2)
atopic keratoconjunctivitis
giant papillary conjunctivitis
How do you assess VKC? (4)
hx, slit lamp, fluoroscein, lid eversion
Describe the pathophysiology of VKC, in relation to Th2 lymphocytes and what they mediate (2)
Th2 lymphocytes mediate:
- reduced IgE via IL-4
- differentiation + activation of mast cells & eosinophils via IL-3 and IL-5 respectively
What might explain improvement in VKC with onset of puberty?
over expression of oestrogen and progesterone receptors in the conjunctiva of VKC patients
What might VKC patients have a hypersensitivity to? (3)
wind, dust, sun
is their a genetic component behind VKC?
Possibly, research has found reduced level of tear film histamine
List tx options for VKC (6)
allergen avoidance (if identifiable, role for allergist)
topical MC inhibitors
corticosteroids
topical NSAIDs
topical cyclosporin
referral for superficial keratectomy to improve resolution of shield ulcer
Name 2 topical MC inhibitors that can tx VKC
Olapatidine (patanol iBD), Ketoifen (zatiden iBD)
Name a corticosteroid that can tx VKC, when would you schedule follow up after using it?
Fluorometholone (FML/Flarex iBD - iQID) - follow up one week after starting therapy
Name 2 topical NSAIDs that can tx VKC
Ketorolac (acular iQID), Diclofenac (voltaren iTDS-iQ3h)
How often should you follow up a VKC px if they have a shield ulcer?
every 1-3 days
How often should you follow up a VKC px during exacerbations?
every few weeks
How often should you follow up a VKC px between exacerbations? (i.e when exacerbations not happening)
less frequently (less frequently than every few weeks)
What type of IOP measurement would be best for VKC patients? Why?
Non-contact tonometry, b/c thin cornea
When do shield ulcers form?
when superficial punctate keratitis (SPK) associated VKC leads to a break in the corneal epithelium