Idiopathic guttate hypomelanosis: idiopathic or ultraviolet induced?

Idiopathic guttate hypomelanosis: Presentation and Management

Idiopathic guttate hypomelanosis (IGH) is a benign, typically asymptomatic, acquired leukoderma characteristically affecting mature individuals. Although the etiopathogenesis is unclear, chronic sun exposure and senile degeneration are important triggers. Researchers have been engaged in a continuous effort to unveil the gray areas encompassing different aspects of IGH pathogenesis. IGH is a clinical diagnosis; however, histopathology and dermoscopy may aid in quetionable cases. Patients often seek cosmetic treatment. There has been no standard therapy for this condition. Newer treatment modalities range from topical agents to procedure-based therapies and have enhanced the therapeutic armamentarium. Here we discuss the pathogenesis, presentation, and management of IGH.

Do oxidative stress and melanin accumulation contribute to the pathogenesis of idiopathic guttate hypomelanosis: A prospective case-control study

BACKGROUND

Oxidative stress parameters have been reported to be significantly higher than controls in diverse disorders of pigmentation but no such data seem to be extant for IGH.

OBJECTIVES

To verify whether heightened oxidative stress levels are seen in patients with IGH (compared with matched controls) and quantify the same in blood using appropriate biochemical markers. Further, an attempt to determine if there might be any correlation between the amount of oxidative stress and the severity of the disease.

METHODOLOGY

This prospective case-control study was conducted in Northern India. Thirty Indian patients (Fitzpatrick skin phototype (SPT) IV-V) were included. The diagnosis of IGH lesions was confirmed based on characteristic clinical, and dermoscopic characteristics and confirmed on histopathological examination (H & E) of one of the lesions.

RESULTS

The oxidative stress enzyme level was significantly higher among the cases compared to controls which were statistically significant (p < 0.05). A positive correlation was also observed between the levels of these markers and number of lesions, but this finding was statistically not significant [p > 0.05]. Assessment of melanin level by Dopa staining method in the IGH lesions revealed irregularly distributed melanin with areas of high and low melanin content and greater accumulation in the basement layer.

CONCLUSION

The results of this probably the first study evaluating oxidative stress in IGH show that the oxidative stress is increased in patients with IGH. Level of oxidative stress seems to be correlated with both age of the patient (more in the elderly) and number of lesions.

Acquired disorders with hypopigmentation: A clinical approach to diagnosis and treatment

Acquired hypopigmented skin changes are commonly encountered by dermatologists. Although hypopigmentation is often asymptomatic and benign, occasional serious and disabling conditions present with cutaneous hypopigmentation. A thorough history and physical examination, centered on disease distribution and morphologic findings, can aid in delineating the causes of acquired hypopigmented disorders. The second article in this 2-part continuing medical education series focuses on conditions with a hypopigmented phenotype. Early diagnosis and appropriate management of these disorders can improve a patient's quality of life, halt disease progression, and prevent irreversible disability.

Melanocyte abnormalities and senescence in the pathogenesis of idiopathic guttate hypomelanosis

BACKGROUND

Idiopathic guttate hypomelanosis (IGH) is a pigmentary disorder of unknown pathogenesis characterized by small discrete white macules. In the skin, epidermal melanin unit between melanocytes and keratinocytes is responsible for melanin synthesis and equal distribution of melanin pigment.

OBJECTIVE

Therefore, this study was designed to check the role of melanocytes in the pathogenesis of IGH.

METHODS

For this study, six IGH patients and six controls were enrolled. Melanin content was checked in the skin sections and in the cultured melanocytes. Senescence was checked in the lesional skin of IGH patients by comparing the mRNA and protein expression of senescence markers p16, hp1, and p21.

RESULTS

Cultured melanocytes from the IGH patients showed morphological changes in comparison to the control melanocytes. Melanocytes from IGH patients were bigger in size with very small and retracted dendrites as compared to the control melanocytes. Melanin accumulation was more in the IGH patients as compared to the controls. Our results showed that expression of p16, p21, and hp1 was significantly higher in lesional skin of IGH patient as compared to healthy controls.

CONCLUSION

This study revealed large-sized melanocytes with small and retracted dendrites in IGH patients. Accumulation of more melanin in the IGH melanocytes might be due to problem in the transfer of melanin from melanocytes to keratinocytes. Accumulation of melanin can lead to the senescence in the melanocytes of IGH patients.

Idiopathic Guttate Hypomelanosis: A Review of its Etiology, Pathogenesis, Findings, and Treatments

Idiopathic guttate hypomelanosis is a common acquired leukoderma characterized by multiple, discrete round or oval, porcelain-white macules on sun-exposed areas, especially on the extensor surface of forearms and pretibial areas. It usually affects individuals aged over 40 years and the likelihood of acquiring it increases with age. The exact pathogenesis remains controversial. However, there are several factors that are believed to be involved such as aging, ultraviolet exposure, trauma, genetic factors, autoimmunity, and local inhibition of melanogenesis. Despite the benign course of progression, many patients visit medical centers owing to cosmetic concerns and to confirm the natural course of idiopathic guttate hypomelanosis. Because there is no standard therapy for this condition, numerous medical and surgical treatments including intralesional corticosteroids, topical retinoids, topical calcineurin inhibitors, phenol peeling, cryotherapy, superficial dermabrasion, skin grafting, and ablative and non-ablative lasers have been tested with mixed results. This article will thoroughly review the etiology, pathogenesis, clinical presentations, histologic, dermoscopic, and ultrastructural findings, and the treatment of idiopathic guttate hypomelanosis.

Skip areas of retained melanin: a clue to the histopathological diagnosis of idiopathic guttate hypomelanosis

Biopsy findings in 55 cases of idiopathic guttate hypomelanosis (IGH) are reported. Most cases had a flat epidermis with loss of the rete pattern and a thickened orthokeratotic basket weave stratum corneum. The epidermis had markedly decreased to absent melanin in the basal layer and reduced numbers of melanocytes at the dermoepidermal junction. One-third of patients had a sparse perivascular lymphocytic infiltrate, whereas the rest had no significant dermal inflammation. These findings are in concordance with current literature. However, small foci of retained melanin in the basal layer (skip areas) alternating with larger areas of melanin loss were present in almost 80% of cases. This finding has not been reported earlier and appears to be quite specific to IGH and may be used as a clue to differentiate IGH from other similar conditions such as vitiligo and guttate morphea.

Treatment of idiopathic guttate hypomelanosis with fractional carbon dioxide lasers

Abstract Objective: Idiopathic guttate hypomelanosis (IGH) is an acquired leukoderma found in all races. The treatment of choice is still controversial. This study aimed at evaluating the effect of CO2FL on IGH. Methods: A total of 240 patients with IGH were enrolled. The hypopigmented lesions were treated using a 10 600-nm carbon dioxide fractional laser (CO2FL). Two months after a single treatment, physicians' clinical assessments were performed and the patients' overall satisfaction was evaluated. Results: 240 patients (40 men and 200 women) were followed. The mean age of the patients was 54.32 ± 8.64 years. The mean duration of IGH was 2.64 ± 0.36 years. Two months after a single treatment session, 115 patients (47.9%) exhibited more than 75% clinical improvement. 100 patients (41.6%) achieved 51-75% clinical improvement, whereas 25 patients (10.3%) showed 25-50% clinical improvement. In addition, 95 of the 240 patients (39.6%) were very satisfied with their clinical outcomes, 102 (42.5%) were satisfied and 43 patients (17.9%) were slightly satisfied. Conclusion: CO2FL might be very effective without any considerable side effects for the treatment of IGH.

The effect of fractional carbon dioxide lasers on idiopathic guttate hypomelanosis: a preliminary study

BACKGROUND

Idiopathic guttate hypomelanosis (IGH) is a commonly acquired leucoderma that is characterized by discrete, round or oval porcelain-white macules ∼2-5 mm in diameter that increases in number with age. A variety of therapies with variable success rates, including cryotherapy, superficial abrasion and topical retinoids are currently being used.

OBJECTIVES

The effects of fractional CO(2) laser therapy on IGH were investigated in this pilot study.

PATIENTS AND METHODS

A total of 40 patients with IGH were enrolled. The hypopigmented lesions were treated using a 10 600-nm carbon dioxide fractional laser (CO(2) FL). Two months after a single treatment, physicians' clinical assessments were performed and the patients' overall satisfaction was evaluated.

RESULTS

The mean age of enrolled patients was 57.5 ± 10.9 years and the gender ratio was 7 : 33. The face was the most commonly treated area, although the extremities are epidemiologically the most frequently affected areas. Two months after treatment, objective assessments performed by two independent dermatologists indicated more than 50% improvement in 36 patients (90%), compared with baseline. In addition, 33 patients (82.5%) were very satisfied or satisfied with just one session of CO(2) FL treatment. Although a few patients complained of long-standing erythema and postinflammatory hyperpigmentation, these problems spontaneously resolved within 2 months after the assessments. No other noticeable side effects were observed.

CONCLUSION

CO(2) FL might be a very convenient and effective modality for treating IGH without significant side effects.

Topical tacrolimus significantly promotes repigmentation in idiopathic guttate hypomelanosis: a double-blind, randomized, placebo-controlled study

BACKGROUND

Idiopathic guttate hypomelanosis (IGH) is an idiopathic disorder affecting a large number of people. Effective treatments are not yet available. Objectives To investigate the efficacy of topical 0.1% tacrolimus ointment compared with placebo in the treatment of IGH.

MATERIALS AND METHODS

Twenty-six patients were included in the study. Lesions on one side of the body were selected to have a treatment with 0.1% tacrolimus ointment, whereas those on the other side served as a control with placebo ointment that had the same physical appearance. Colorimeter was used to assess skin colour at baseline and at 1, 2, 3, 4 and 6 months of treatment.

RESULTS

Mean luminosity scale after adjusted for baseline from the treated side gradually decreased and reached statistical significance compared with the control group after 6 months of treatment (P = 0.019). Physicians' improvement grading score showed that 11% of the patients demonstrated improvement of their skin lesions on the treated side after 6 months' treatment.

CONCLUSION

Topical 0.1% tacrolimus ointment appeared to be an effective and safe treatment for IGH. The improvements were best observed by colorimetry, yet, they were not statistically significant upon clinical assessments.

Leucodermia punctata após tratamento com Puvasol tópico

Duas adolescentes e uma menina com vitiligo clinicamente diagnosticado foram tratadas com 8-metoxipsoraleno a 0,2% em creme Lanette com subsequente exposição solar. Um ano após, apresentaram máculas acrômicas na área do vitiligo. A biópsia de pele em um dos casos revelou melanócitos com escassa pigmentação melânica. Os achados clínicos e histológicos sugerem o diagnóstico de leucodermia punctata.

Idiopathic guttate hypomelanosis-like lesions in patients with mycosis fungoides: a new adverse effect of phototherapy

BACKGROUND

Idiopathic guttate hypomelanosis (IGH) is a common pigmentary disorder, the aetiology and pathogenesis of which are largely unknown. The appearance of IGH-like lesions during phototherapy has been reported previously in only one patient.

OBJECTIVE

To describe the clinical and histological features of phototherapy-induced IGH-like lesions, their relation to ultraviolet dosimetry and the course of this eruption in patients with mycosis fungoides (MF).

METHODS

The files of all patients with MF who underwent phototherapy in our centre from 1992 to 2008 were searched to identify those in whom IGH-like lesions appeared during treatment. Results Among 87 patients with early-stage MF who underwent phototherapy, seven acquired IGH-like lesions during monotherapy with narrow-band ultraviolet B (NB-UVB; four patients) or psoralen and ultraviolet A (PUVA; three patients). All but one had a light complexion. The lesions appeared in areas exposed to ultraviolet light, and not exclusively on the skin previously involved by the disease. The mean number of exposures until appearance of the lesions was 92 for NB-UVB and 137 for PUVA. Biopsy study showed a decreased number of melanocytes. Phototherapy was discontinued in four patients, of whom three showed a partial or complete disappearance of the IGH-lesions. The other three patients are still receiving phototherapy, with no change in their IGH-like lesions.

CONCLUSIONS

Phototherapy may induce an eruption bearing similar clinical and histopathological features to IGH. The eruption is rare, appears to emerge only after prolonged therapy and seems to be reversible upon discontinuation of phototherapy. IGH-like eruption should be added to the list of side-effects of phototherapy.

Pigmentary disorders in the Mediterranean area

The Mediterranean area represents the area of land that borders the Mediterranean basin. It is composed of several countries that share many geographic and racial characteristics. Although Mediterraneans seem to share common skin type and are subjected to similar enviromental factors, they still represent a genetic and socioeconomic diversity. True prevalence of pigmentary disorders in this area depends on large epidemiologic studies, including countries that are not available. This article, however, highlights and classifies the most important developmental (heritable-genetic) and acquired pigmentary disorders seen and reported in this important area of the world.