Vitiligo Microphototherapy

Vitiligo is a common disease of unknown cause that
produces disfiguring white patches of depigmentation. Previous
studies have suggested the effectiveness of UV-B radiation in
generalized vitiligo (GV) therapy, but there was no evidence to
support the same role for segmental vitiligo (SV).

*Objective:* The purpose of this study was to use UV-B radiation
exclusively on vitiligo patches of individuals affected by SV to
evaluate the effectiveness of this therapy.

*Subjects & Methods:* 8 individuals with SV were treated for six
months with a new device called BIOSKIN ® that can produce a focused
beam of UV-B (microphoto-therapy) on vitiligo patches only.
Photographs of the subjects were taken at the beginning of the
therapy and once a month thereafter for six months. The response to
treatment was estimated in 2 comparable photographs using
planimetry. A control group of 8 individuals matched for sex and age
was treated with placebo, using the same device but not releasing
any kind of detectable light.

*Results:* After six months of microphototherapy 5 subjects of the 8
studied achieved normal pigmentation on more than 75% of the treated
areas. In particular, 3 of these were totally repigmented. Two
individuals achieved 50-75% pigmentation of the treated areas, and
only one showed less than 50% repigmentation (table 3). In the
control group only one patient showed moderate repigmentation (less
than 50%) (table 3) (Figure 1).

*Conclusion:* UV-B microphototherapy seems highly effective in
restoring pigmentation in patients affected by vitiligo. As no side
effects have been observed, this could represent the treatment of
choice in the limited (segmental) forms of vitiligo.

*Keywords:* vitiligo, UV-B, therapy



*Introduction
*
Vitiligo is an acquired hypomelanotic disease of unknown etiology
affecting 1-2% of world population without any racial, geographic or
sex differences (1). Although use of ultraviolet-B (UV-B) radiation
in vitiligo therapy is relatively recent, it is considered presently
the most effective treatment for generalized vitiligo (1,2).

The successful use of UV-B rays is probably due to several direct
and mediated interactions of UV-B with melanocytes, keratinocytes
and skin immune system (Table 1).

Enhancement of pigmentation
- By increase of melanocyte stimulating hormone (MSH) receptor
binding activity and melanocortin receptor gene expression [3]
- By activation of cyclic-AMP pathway by alpha-melanotropin which
increases melanocyte proliferation and melanogenesis [4]
- By irradiated keratinocyte production of nitric oxide (NO)
(paracrine induction of melanogenesis) [5]
- By increase of tyrosinase mRNA expression and enzymatic activity [6]
- By melanocyte production and secretion of corticotropin releasing
factors [7]
lnduction of skin inflammation
- By enhancement of keratinocyte production and release of TGFß-1 [8]
- By enhancement of keratinocyte production and release of IL-1 [9]
Alteration of local (skin) immune system response
- By enhancing production and release of TGFß-1which causes
immunosuppression [8]
- By enhancing release of cis urocanic acid (cis-UCA) [10]
By enhancing keratinocyte production and release of TNFß [11]
Tumor promotion
- By induction of c-jun and c-fos protooncogene transcription in
keratinocytes [12]
- By causing cellular DNA damage
Cellular programmed self destruction
- By increasing keratinocyte levels of tumor suppressor gene p53 [13,14]
- By increasing keratinocyte Ievels of 1.25 dihydroxyvitamin D3,
TGFß-1,Ca ^2+ [15]
Metabolic alteration
- Enhanced production of free radical levels
- Enhanced superoxid dismutase (SOD) levels and activity [16]

Table 1 - The main direct and mediated effects of UV-B irradiation
of the skin

In this study we used a new device called BIOSKIN^® provided with a
focused beam of UV-B adapted to treat selected areas of depigmented
skin.

*Subjects and Methods*

/Subjects/

Subjects with segmental vitiligo were included in the study after
obtaining informed consent to ensure that the procedure of
microphototherapy had been fully explained. The individuals were 4
men and 4 women with a mean age of 17.9 years and skin type III for
6 persons and II for the other 2. The control group was composed of
8 individuals, 5 men and 3 women, affected by SV with a mean age of
22.9 years; skin type was III for 5 persons and II for the other 3.

Table 2 shows the sex, age, Fitzpatrick skin phototype and affected
areas for each subject treated.