Investigation of suitable starting doses of narrowband UVB in Asian vitiligo patients: a pilot study.

BACKGROUND

Phototherapy is the preferred treatment modality for active and generalized vitiligo. One of the widely accepted consensus on starting dose of phototherapy is using a uniform dose of 280 mJ/cm2 regardless of patients' Fitzpatrick skin phototype (SPT). However, in many clinical experiences with Asian vitiligo patients, the protocol seems suboptimal.

OBJECTIVE

To gather more evidence on establishing a higher starting dosage for Asian vitiligo patients undergoing phototherapy.

METHODS

We enrolled generalized vitiligo patients with lesions sized adequate enough for phototest. Minimal erythema dose (MED) of vitiligo lesion and non-lesion was measured along with melanin index (MI).

RESULTS

Relatively, a wide range of MED and MI was observed even among patients with similar SPT. The range of MED for lesional skin was 300-700 mJ/cm2 and the MED for non-lesion was 500-800 mJ/cm2 . Correlation was noted between lesional MED and non-lesional MI (Spearman correlation, ρ = 0.664 [P < 0.036]) and mean lesional MED was approximately 65% of mean non-lesional MED.

CONCLUSION

Results from phototest and tolerability of patients to doses higher than 280 mJ/cm2 may indicate that higher starting doses might be appropriate for Asian vitiligo patients.