Topical tacrolimus in atopic dermatitis: Effects of ... - Helda - Helsinki.fi

Results of the present uncontrolled study on conjunctival cytology samples
showed a clear decrease in the number of all inflammatory cells; this was in good
agreement with clinical signs and subjective symptoms. Studies have shown that
sodium chromoglycate or its derivatives inhibit mast cells and eosinophils to some
degree in different types of allergic conjunctivitis. Nedocromil sodium reduced the
concentrations of neutrophils, eosinophils, and lymphocytes in tear fluid by 72%, 88%,
and 88% in patients with vernal conjunctivitis, but this finding did not reach statistical
significance when compared with placebo (Bonini et al. 1992). After a conjunctival
allergen challenge, lodoxamide-pretreated eyes showed 96% fewer eosinophils than
placebo-treated eyes in tear fluid (Bonini et al. 1997). These substances are, however,
insufficient to control the chronic atopic blepharoconjunctivitis in clinical practice. In
our study their possible impact on clinical score or on cytological results was considered
insignificant.
The modern antihistamine eye-drops have been shown to have anti-inflammatory
properties in allergic reactions in vitro (Bielory et al. 2005). In placebo-controlled
conjunctival allergen challenge settings in vivo, azelastine reduced counts of
neutrophils, eosinophils, and lymphocytes in conjunctival scrapings in a conjunctival
allergen challenge by 65%, 62%, and 82% (Ciprandi et al. 2003), and olopatadinepretreated
eyes showed 93%, 69%, and 80% fewer neutrophils, eosinophils, and
lymphocytes in tear fluid than did placebo-treated eyes (Leonardi & Abelson 2003).
Ketotifen has inhibited eosinophil function in an animal model of allergic conjunctivitis
(Schoch 2003). At present, the effect of these agents on chronic atopic
blepharoconjunctivitis remains unknown.
Tacrolimus eye-drops have inhibited the infiltration of eosinophils and
lymphocytes as well as the late and delayed-type inflammatory response of
experimental animal allergic conjunctivitis with an efficacy similar to that of
betamethasone 0.1% and fluorometholone 0.1% eye-drops (Nishino et al. 2002,
Sengoku et al. 2003). In the present study, tacrolimus was not applied directly to the
eye. It is unclear how the treatment of the eyelids caused the improvement in the
conjunctiva. The patients did not complain of any marked irritation as a sign of the
ointment getting into the eyes. A systemic effect through such a small treatment area is
unlikely. The most likely explanation is diffusion of the drug through the eyelid to the
conjunctiva or that an improvement in the severe eyelid inflammation propagates to the
adjacent conjunctival tissue.
Our clinical observations based on patients outside this study suggest a longer
remission after the treatment period with tacrolimus ointment than with topical
glucocorticoids, a good and well-maintained long-term treatment response, and also a
diminished need for simultaneous eye- drop treatments. The decrease in the need to
treat conjunctivitis separately, together with long-term disease control, is likely to
improve patients’ quality of life.
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