Blue vitiligo

Clinical visible signs of disease activity in vitiligo: a systematic review and meta-analysis

Vitiligo is an unpredictable depigmenting disorder for which a static method to assess disease activity is lacking. Presence of certain skin manifestations may be indicative of disease activity. Here, we evaluated the current evidence for an association between clinical signs and reported disease activity in vitiligo. A systematic review and meta-analysis was performed based on a search in PubMed, Embase and Cochrane Library. Literature reporting skin manifestations and disease activity was analysed based on descriptive analyses and, if applicable, odd ratios. Forty-six observational studies were selected and analysed, including 28 case reports. Reported clinical signs in relation to active vitiligo were as follows: Koebner's phenomenon, confetti-like depigmentations, tri- and hypochromic lesions (including poorly defined borders), inflammatory borders/areas, itch and leukotrichia. Based on this search, strong evidence was found for Koebner's phenomenon. Poorly defined borders and confetti lesions are potential markers, although more data are needed to confirm this. Evidence for other skin manifestations was inconclusive, whereas case reports on inflammatory borders were indicative of active disease. Limitations included the lack of randomized controlled trials, large-scale prospective studies and heterogeneity due to inconsistent definitions. This systematic review urges the vitiligo community to come forward with consensus-based definitions as well as a reliable scoring system to assess these clinical signs and to design optimal trials to investigate their true predictive value.

Blue vitiligo following intralesional injection of psoralen combined with ultraviolet B radiation therapy

A 23-year-old Chinese man presented with a 16-month history of white patches on his abdomen and neck. He had previously received an intralesional injection of psoralen along with narrowband psoralen ultraviolet B radiation (PUVB) therapy. Blue macules had appeared in and around the injection sites 1 week later. Dermoscopy revealed blue spots and reticular telangiectasia within the white patches. Histological examination revealed an absence of epidermal melanocytes and pigment in the basal layer, as well as deposition of melanophages between collagen bundles or surrounding blood vessels and appendages in the middle and lower parts of the dermis. A diagnosis of blue vitiligo was made. The blue colour faded gradually over time. Our case provides direct evidence to support the previous surmise that PUVB can contribute to blue vitiligo. To our knowledge, this is only the fourth reported case of blue vitiligo in the English literature.

Monte Carlo simulation of cutaneous reflectance and fluorescence measurements – The effect of melanin contents and localization

Melanin content and distribution in skin were studied by examining a patient with white, brown and blue skin tones expressed on skin affected by vitiligo. Both diffuse reflectance and autofluorescence spectra of the three distinction skin sites were measured and compared. Monte Carlo simulations were then performed to help explain the measured spectral differences. The modeling is based on a six-layer skin optical model established from published skin optical parameters and by adding melanin content into different locations in the model skin. Both the reflectance and fluorescence spectra calculated by Monte Carlo (MC) simulation were approximately in agreement with experimental results. The study suggests that: (1) trichrome vitiligo skin may be an ideal in vivo model for studying the effect of skin melanin content and distribution on skin spectroscopy properties. (2) Based on the skin optical model and MC simulation, the content and distribution of melanin in skin, or other component of skin could be simulated and predicted. (3) Both reflectance and fluorescence spectra provided information about superficial skin structures but fluorescence spectra are capable of providing information from deeper cutaneous structures. (4) The research method, including the spectral ratio method, the method of adding and modifying the melanin content in skin optical models, and MC simulation could be applied in other non-invasive optical studies of the skin.

Spectroscopic assessment of dermal melanin using blue vitiligo as an in vivo model

BACKGROUND

Spectroscopic methods have been used to analyze in vivo melanin in the past but the specific effect of melanin depth on autofluorescence and reflectance spectroscopy has not been determined. In patients with blue vitiligo, three distinctive clinicopathologic patterns are present: (1) normal skin with normal epidermal melanin pigmentation (2), skin of blue vitiligo with dermal melanin pigmentation, and (3) tissue of regular vitiligo with no melanin pigmentation. Blue vitiligo may thus serve as an in vivo model to assess dermal pigment using spectroscopic techniques.

OBJECTIVES

To evaluate the reflectance and autofluorescence spectra of a patient with blue vitiligo in order to assess the effect of melanin pigmentation and its localization on the optical properties of the skin.

METHODS

The blue-gray, normal and depigmented lesions of a patient with blue vitiligo were analyzed using reflectance and fluorescent spectroscopy. The condition was likely induced by a phototoxic reaction in a patient with pre-existing vitiligo. These data were then correlated to the histologic and electron microscopic findings present in the various types of lesions.

RESULTS

Reflectance spectroscopy detected little difference in spectral shape between skin sites affected by blue vitiligo vs. vitiligo. Autofluorescence spectroscopy detected an apparent difference between the two types of lesions, with the blue-gray lesions (blue vitiligo) showing lower fluorescence intensity and spectral maximum position red-shifted compared with regular vitiligo, whereas regular vitiligo showed more intense hemoglobin absorption than the blue vitiligo.

CONCLUSIONS

Dermal melanin present in blue vitiligo can be well characterized by autofluorescence spectroscopy, while little difference in reflectance spectral shape exists between vitiligo and blue vitiligo. Thus, autofluorescence spectroscopy may better identify deeper structures in skin tissue, such as melanin, than reflectance spectroscopy.

Cytomegalovirus DNA identified in skin biopsy specimens of patients with vitiligo

BACKGROUND

Viral infections have been implicated in the pathogenesis of a variety of autoimmune diseases.

OBJECTIVE

This investigation was undertaken to determine the presence or absence of viral genomes in the depigmented and uninvolved skin of patients with vitiligo.

METHODS

A polymerase chain reaction assay was used to detect viral genomes in paraffin-embedded skin biopsy specimens. Twenty-nine patients with vitiligo and 22 control subjects were included. Biopsy specimens were screened in a blinded fashion for a panel of DNA and RNA viruses including herpes simplex, varicella-zoster, cytomegalovirus (CMV), Epstein-Barr, HIV, and human T-cell lymphotropic virus.

RESULTS

CMV DNA was identified in 38% of the patients studied. Twenty-one percent had indeterminate results. Results in all control subjects were negative. Polymerase chain reaction screening for identification of other viral genomes was negative. Although not statistically significant, data trends suggested a correlation between the presence of CMV DNA in biopsy specimens and active vitiligo of relatively brief duration. In addition, CMV-positive patients had a statistically significant increased frequency of other concurrent autoimmune diseases.

CONCLUSION

CMV DNA in the depigmented and uninvolved skin of some patients with vitiligo and its absence in control subjects suggest that vitiligo may indeed be triggered by a viral infection in select patients.