Healthcare and Medicine Reference
In-Depth Information
ATOPIC KERATOCONJUNCTIVITIS
Atopic keratoconjunctivitis is the most severe form of chronic allergic ocular
disorder, affecting eyelids, conjunctiva and cornea. It is usually part of a
dysregulated systemic immune condition, associated with atopic dermatitis
and other allergic manifestations.
Epidemiology
The real prevalence of AKC may only be speculated: from 15% to 67.5%
of subjects with atopic dermatitis have an ocular involvement and atopic
dermatitis affects about 3-9% of the general population (Yanni and Barney
2008). Ocular manifestations usually begin in the second through fi fth
decade, although the onset of symptoms is reported from 7 up to 76 years
of age. It is not clear if there is a gender prevalence. No racial or geographic
predilection is described.
Clinical Features
AKC can manifest in different degrees of severity, from mild to blinding
forms. It is usually bilateral and often asymmetrical.
A history of atopic dermatitis should be specifi cally questioned; in
some cases the disease is evident only in childhood and there are no other
pathological signs but in the ocular region in the adults.
Symptoms as itching, burning, tearing, mucus discharge, and
photophobia vary in intensity and duration. It can affl ict patients all year
long or seasonally.
Typically anterior and/or posterior blepharitis impairs the eyelids;
consequently, the tear film is often altered by the meibomian gland
dysfunction. The skin of the lids may appear eczematous, thinning or
thickening, lichenifi ed and even macerated ( Fig. 1e ). Staphilococcus aureus
infection is most likely to complicate the aspect of the skin.
Conjunctival infl ammation may be localized both in the superior and
inferior fornix and tarsal plate, accompanied by intense hyperemia and
chemosis. In severe cases papillary hypertrophy and giant papillae in the
upper tarsal area and gelatinous perilimbal infi ltrate may develop, as in
VKC. Occasionally the scarring process, due to long-lasting swelling, can
determine a fornix foreshortening and even a symblepharon.
Cornea is injured in 75% of cases. Punctuate epithelial keratopathy
and epithelial defects are mild signs, while corneal erosions, thinning,
neovascularization, shield ulcers and plaque are worsening manifestations
( Fig. 1f ).
Search Pocayo ::




Custom Search