Effectiveness of Artificial Balneotherapy, Phototherapy and Artificial Balneophototherapy in the Treatment of Psoriasis

On the selected subjects, it was also performed the evaluation of Minimal Erythema Dose (MED) in order to determine an acceptable dose of UV-B light for the type of skin of each patient. Thus, the evaluations were performed according to psoriasis type, area, color and plaques severity. The formula used for the calculation was:

MED = 2×t(s)×0,75 t: minimum time for erythema occurrence.

Each psoriatic plaque was submitted to three therapeutic sessions per week, during 4 weeks, for a total of 12 sessions.

For the application of AB, the AB group plaques were immersed during 15 minutes in a 35 or 75 l hydrotherapy whirlpool (TB-T45 model and TB-T90 model respectively, Enraf Nonius Company SA, Spain) filled with a solution of warm water (32 °C) and natural sea salt (250 g/L), following the similar protocol of others authors always ensuring that the plaques not receiving this treatment were kept isolated with flexible and insulating adhesive patches (Nexcare® Factory 3M, Chile).

For the implementation of PT, the PT group plaques that would not receive radiation were covered with thick cloth towels, while the healthy skin surrounding the treated plaques were coated with liquid petroleum jelly. Both patients and attendant were protected with special lenses with filter against UV light (Oakley Jupiter, USA). UV-B radiation was applied with the UV Endolamp 474 device (Enraf Nonius Company SA, Spain), 60 cm away from the plaque and in a perpendicular position. In session 1, the MED was calculated for each subject and used as the time of UV-B exposure. On each further session, the exposure time was increased by 25%, until the limit of 5 minutes.

The BPT group plaques received both AB and PT treatments, on the same conditions described above, consecutively.

The C group plaques did not receive any treatment.

Data Collection The plaques were photographed at a distance of 20 cm with a 12 pixel Lumix digital camera (Panasonic, USA). For area quantification, the photographs were taken before session 1 and a day after session 6 and 12, and were analyzed with ImageJ software (version 1.46j; National Institute of Health, MD, USA). For color evaluation, the photographs taken before session 1 and after session 12 were analyzed with the Average color seeker software (Version 0.41; IDimager Systems Inc., Scotts Valley, CA, USA), which uses the Red-Green-Blue (RGB) coordinates system that reports the information about the red color channel, associated to erythema occurrence, in arbitrary units. Therefore, greater red color measurements for skin pigmentation may indicate increased erythema.

The psoriatic plaque severity was assessed before session 1 and one day after session 12 through PASI, which considers erythema, induration and plaque scaling, being 72 points the maximum score.

Quality of life assessment was performed using the SF-36 TM v2 health questionnaire, validated for the Chilean population10, and with the psoriasis disability index (PDI), both performed before session 1 and one day after session 12.