Instrumental analysis of the pattern of improvement and that of recurrence of melasma in Thai females treated with Kligman-Willis triple combination therapy: confirmation by using its two different formulae.

BACKGROUND: Melasma is common among females. At present, its most reliable topical treatment is the Kligman-Willis formula. OBJECTIVES: To evaluate objectively the pattern of pigmentation improvement and recurrence. METHODS: Thirty-four Thai females with melasma showing similar lesions on both cheeks were randomly assigned to 8-week daily treatment with either one of two different versions of the formula together with strict sun protection. They were objectively evaluated instrumentally with a Mexameter® every 2 weeks, and were followed up for the subsequent 40 weeks. RESULTS: Thirty of 34 subjects who completed their 8-week treatment displayed a similar improvement pattern with either formulae. All expressed satisfaction with the results of the treatment. Instrumental evaluation detected that the pigmentation reached a nadir after 6 weeks, regardless of the formulae. Twenty-one subjects, who were further followed up, exhibited mild relapse within 2 months after finishing the treatment. Yet, their pigmentation levels remained significantly lower than those before treatment. Both formulae increased transepidermal water loss and skin surface hydration during the treatment period. CONCLUSION: Melasma in Thai females responded well to the Kligman-Willis formula. A relapse that was detected with the instrumental measurement after treatment discontinuation suggests the necessity to continue even intermittent treatment after attaining therapeutic success.

Adult-onset actinic prurigo in Thailand.

BACKGROUND: Actinic prurigo (AP) is one of the rare idiopathic photodermatosis. It is said to be a familial disease and is usually seen in certain specific geographical areas. The adult-onset type of AP is reported less frequently in the Asian population and has never been reported in Thailand. METHODS: The study population comprised 30 patients. Demographic data were collected. Photo-tests and photo provocation tests for UVA, UVB and visible light were carried out on non-exposed skin. The other investigations included antinuclear antibody, anti-HIV antibody and urine porphyrin level. Histopathology studies were also carried out. RESULTS: There were 18 males and 12 females. The mean age of onset was 36.86 years. The duration of disease was from 1 month to 20 years. Forearms (27 patients) were the most frequently affected site. Other screening tests showed negative results. Five patients had abnormal MED to UVA and one patient had abnormal MED to UVA as well as UVB. Photo provocation tests showed positive responses to both UVA and UVB in 12 cases (40%), a positive response to UVA in 11 cases (37%), a positive response to UVB alone in four cases (13.3%) and a normal response in three patients (10%). None of the patients had a positive response to visible light. Skin biopsies were performed on nodular lesions in 23 cases. Histopathology from these 23 cases showed hyperkeratosis ortho- or parakeratosis and acanthosis in 20 of the 23 cases. CONCLUSIONS: Adult-onset AP in our country may have different geographic and racial distribution from previous reports or may be the tropical variant as described by Tham et al. It may not be an uncommon disease in our country, if there is increased awareness of this disease. Only 16.6% of patients had reduced MED. Photo provocation tests were positive in 90% of cases. Most of the positive wavelengths were UVA or both UVA and UVB. Therefore, photo provocation tests should be performed in cases suspected of AP. The prognosis for AP is not good, despite combinations of treatment. The disorder may run a chronic course. This may be because of our sunny climate and the sun-exposed occupations of patients.