Solar urticaria: a report on 57 cases.
BACKGROUND
Solar urticaria (SU) represents an uncommon skin disorder, characterized by pruritic erythema and wheals after sun exposure, that sometimes restricts normal daily life.


OBJECTIVE
To evaluate data concerning sex, age, natural history, associated diseases, and eliciting wavebands of 57 SU cases.


METHODS
Questionnaire for anamnestic data, laboratory examinations, phototesting.


RESULTS
Sex: 25 (44%) males, 32 (56%) females. Age: The peak age was between 20 and 30 years. Skin type (ST): 12 (21%) ST II, 39 (68%) ST III, and 6 (11%) ST IV. Time between onset and complete disappearance of SU was from 2 to more than 6 years; the main peak (37 patients) between 4 and 6 years. There were histories of atopic dermatitis 12 (21%) and asthma or rhinitis 15 (26%). Association with other urticarias (U): 13 (21%) dermographic U, 2 food U, 3 heat U. Increased immunoglobin E (IgE): 19 (33%). Eliciting wavebands: 38 (67%) visible light (VIS), 16 (28%) long ultraviolet (UVA), 3 natural sunlight. Minimal urticarial dose (MUD): 20-37.5 J/cm2 for VIS-sensitive patients, 5-10 J/cm2 for UVA.


CONCLUSIONS
In our series: 1. SU affects both sexes usually when they are under 30 years of age; 2. nearly half the patients are free of disease within 5 years; 3. in about one fourth of cases SU is associated with dermographic urticaria or displays a history of atopic dermatitis; 4. the wheals are elicited mainly by VIS or UVA; 5. SU can be prevented, at least in part, by antihistamines or by PUVA therapy.
Monfrecola
G
G
Department of Dermatology, University Federico II, Naples, Italy. monfreco@unina.it
Masturzo
E
E
Riccardo
A M
AM
Balato
F
F
Ayala
F
F
Di Costanzo
M P
MP
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D002648:Child; D017454:Dermatitis, Photoallergic / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D008027:Light / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D011795:Surveys and Questionnaires; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014581:Urticaria / Q000453:epidemiology* / Q000209:etiology