Comparison of racial distribution of photodermatoses in USA academic dermatology clinics: A multicenter retrospective analysis of 1080 patients over a 10-year period.

BACKGROUND: Previous studies at single academic institutions have identified variations in the prevalence of photodermatoses among racial groups. The purpose of the study was to compare the distribution of photodermatoses between Whites and Blacks at four academic medical centers in the USA. METHODS: A retrospective chart review was performed at four institutions' general dermatology clinics using diagnoses consistent with the International Classification of Disease (ICD), Ninth and Tenth Revisions, codes related to photodermatoses between August 2006 and August 2016. A total of 9736 charts were manually reviewed and classified. Analyses were performed analyzing the frequency of photodermatoses between Whites and Blacks in the pooled data. RESULTS: There were 1,080 patients with photodermatoses identified. Statistically significant differences in the frequency of photodermatoses between Whites and Blacks were identified for polymorphous light eruption (more common in Blacks), photoallergic contact dermatitis, phototoxic drug eruption, phytophotodermatitis, porphyria, and solar urticaria (more common in Whites). The most commonly diagnosed photodermatoses were polymorphous light eruption (total 672), and photodermatitis not otherwise specified (total 189). CONCLUSION: Our study demonstrated significantly higher proportions of polymorphous light eruption in Blacks, and higher proportions of photoallergic contact dermatitis, phototoxic drug eruptions, phytophotodermatitis, porphyrias, and solar urticaria in Whites.

Actinic Prurigo in Singaporean Chinese: A Positive Association with HLA-DRB1*03:01.

Studies have reported the association of human leukocyte antigen (HLA) genes with susceptibility to develop actinic prurigo (AP) in Caucasians, but there were no studies in Asian populations, including the Chinese. Our study was performed to determine if AP is associated with susceptibility or protective HLA alleles or haplotypes in Singaporean Chinese. All Chinese patients diagnosed with AP at National Skin Center, Singapore, from January 2002 to April 2015 were invited to participate in the study. Clinical data and phototesting results were collated, and HLA typing was performed. Among 14 patients included, 11 were male and the mean age was 49.6 (37.9-61.3) years. All patients did not have a family history of AP and none had mucosal involvement, as such these clinical features differed from Caucasian AP patients. The frequency of DRB1*03:01 in AP patients was significantly higher compared to healthy controls (43% vs 16%, P = 0.022, odds ratio (OR) 3.89). Concurrently, the frequency of HLA-B*58:01-DRB1*03:01 haplotype was also significantly increased (25% vs 7%, P = 0.004, OR 4.23). In conclusion, HLA-DRB1*03:01 was associated with AP in Singaporean Chinese patients. This novel allelic association may possibly be utilized as a biological marker to aid in the diagnosis of AP in Chinese patients.

Dermatology in the North American Indian/Alaska Native population.

Dermatology is greatly understudied in the American Indian/Alaska Native (AIAN) population. This topic deserves attention in light of the changing demographics of the United States and the healthcare disparities faced by AIAN, including access to dermatologic care. In this review, we discuss disorders that are more prevalent or otherwise important in the AIAN population, such as cutaneous malignancies, photodermatoses, acanthosis nigricans, connective tissue disorders, cutaneous infections, hypertrophic scar formation, and Heck's disease. We aim to provide an updated review and increase awareness of the dermatologic needs of the AIAN population.

Self-reported pigmentary phenotypes and race are significant but incomplete predictors of Fitzpatrick skin phototype in an ethnically diverse population.

BACKGROUND: Fitzpatrick skin phototype (FSPT) is the most common method used to assess sunburn risk and is an independent predictor of skin cancer risk. Because of a conventional assumption that FSPT is predictable based on pigmentary phenotypes, physicians frequently estimate FSPT based on patient appearance. OBJECTIVE: We sought to determine the degree to which self-reported race and pigmentary phenotypes are predictive of FSPT in a large, ethnically diverse population. METHODS: A cross-sectional survey collected responses from 3386 individuals regarding self-reported FSPT, pigmentary phenotypes, race, age, and sex. Univariate and multivariate logistic regression analyses were performed to determine variables that significantly predict FSPT. RESULTS: Race, sex, skin color, eye color, and hair color are significant but weak independent predictors of FSPT (P<.0001). A multivariate model constructed using all independent predictors of FSPT only accurately predicted FSPT to within 1 point on the Fitzpatrick scale with 92% accuracy (weighted kappa statistic 0.53). LIMITATIONS: Our study enriched for responses from ethnic minorities and does not fully represent the demographics of the US population. CONCLUSIONS: Patient self-reported race and pigmentary phenotypes are inaccurate predictors of sun sensitivity as defined by FSPT. There are limitations to using patient-reported race and appearance in predicting individual sunburn risk.

Comparison of photodermatoses in African-Americans and Caucasians: a follow-up study.

BACKGROUND/PURPOSE: Only a few studies have compared frequencies of photodermatoses among different races and skin types. This is an extension of a study performed by Kerr and Lim and evaluates the frequency of photodermatoses in African-Americans compared with Caucasians in the same institution during an 8-year period. METHODS: Retrospective chart review was performed, including dermatology clinic charts from October 2004 to August 2012 with International Classification of Diseases, Ninth Revision diagnostic codes related to photodermatoses. RESULTS: We identified 229 patients with photodermatoses. Of these, 138 (46.6%) were African-American and 63 (42.2%) were Caucasian. Statistically significant differences in the distribution of photodermatoses in African-Americans and Caucasians, respectively, were as follows: phototoxic drug eruption (0.7% and 15.9%, P < 0.0001), phytophotodermatitis (0% and 6.3%, P = 0.009), polymorphous light eruption (PMLE) (86.2% and 54%, P < 0.0001) and porphyrias (0% and 7.9%, P = 0.003). CONCLUSION: Combined with data from Kerr and Lim, this is the largest study of photodermatoses in African-Americans to date. Congruent to former studies, photodermatoses do occur regularly in dark-skinned individuals. Overall, the frequency of photodermatoses in African-Americans and Caucasians are similar; however, PMLE occurs more commonly in African-Americans, and porphyias and phototoxicity occur more commonly in Caucasians.

Clinical characteristics of adult-onset actinic prurigo in Asians: a case series.

BACKGROUND: Actinic prurigo (AP) is a chronic, pruritic skin condition caused by an abnormal reaction to sunlight. AIMS: The aim of this study is to determine the clinical characteristics of AP in patients attending the National Skin Centre, Singapore, from 1 st January 1999 to 30 th June 2008. METHODS: Cases of AP diagnosed from 1 st January 1999 to 30 th June 2008 were retrieved from the center's electronic medical records and analyzed. RESULTS: A total of 11 patients were diagnosed with AP. The mean age at diagnosis was 52 years. There were 9 (82%) Chinese and 2 (18%) Malay patients. Nine (82%) were male and 2 (18%) were female. The most commonly affected areas were the face, forearms, and hands (72%). Phototesting showed reduced minimal erythema dose (MED) to ultraviolet A (UVA) in 5 (46%) patients, both UVA and ultraviolet B (UVB) in 4 (36%) patients and UVB in 1 (9%) patient. Seven (64%) patients reported partial improvement after treatment with a combination of topical corticosteroids and sunscreens. Four (36%) patients received systemic therapy with partial response. CONCLUSION: Adult-onset AP is more common in the Asian population, with a male predominance. The face, forearms, and hands are the most commonly affected areas. The absence of mucosal involvement is also a distinguishing feature between the Asian and Caucasian population. Close to half of the patients have reduced MED to UVA on phototesting. The prognosis for AP is poor as it tends to run a chronic course with suboptimal response to treatment.

Chronic actinic dermatitis in Asian skin: a Singaporean experience.

BACKGROUND/PURPOSE: To study the characteristics of chronic actinic dermatitis (CAD) in a heterogeneous group of Singaporean patients. METHODS: The photobiologicial features of all patients phototested and diagnosed with CAD from January 2005 to December 2009 were examined retrospectively. RESULTS: Fifty-eight patients were diagnosed as having CAD. The mean age at diagnosis was 62 years (range 35-83). Forty-one were (70.7%) Chinese, six (10.3%) Indians, eight (13.8%) Malays, and three (5.2%) Others. Forty-seven were (81.0%) male and 11 (19.0%) were female. Forty-nine (84.5%) had Fitzpatrick skin phototype IV and nine (15.5%) had phototype V. Three of 26 (11.5%) tested for human immunodeficiency virus were positive. The face, neck, and forearms were most commonly affected. Thirty-two patients (55.2%) had reduced minimal erythema dose (MED) to both ultraviolet B (UVB)and ultraviolet A (UVA), 23 patients (39.7%) had lowered MED to UVB only, while three (5.1%) had reduced MED to UVA only. Patients were followed up for a mean of 16.8 months. All were treated with photoprotection and topical steroids; however, a few required oral immunosuppression with partial improvement. CONCLUSION: In Singapore, CAD was seen more commonly in elderly Chinese males of Fitzpatrick skin phototype IV. Reduced MED to both UVB and UVA was the most common phototest finding.

Single-nucleotide polymorphisms of MAMDC1 are associated with rash and photosensitivity, but not disease risk, of systemic lupus erythematosus in Chinese mainland population.

Systemic lupus erythematosus (SLE) is a complex immune disease affected by both genetic dispositions and environmental factors. Recently, the polymorphisms in MAMDC1 gene have been reported to associate with disease risk of SLE in European population. However, whether this association is replicated in Chinese population is unknown yet. A total of 491 SLE patients and 533 controls were recruited. Unlabeled probe-based high-resolution melting analysis (HRMA) was used in genotyping. HRMA with unlabeled probe successfully distinguished all genotypes. SNP rs961616 was associated with rash [P = 0.015, odds ratio (OR) = 0.73, 95% confidence interval (CI) = 0.57-0.94] and photosensitivity (P = 0.001, OR = 0.63, 95%CI = 0.48-0.84), but not the disease risk (P = 0.133, OR = 0.88, 95%CI = 0.74-1.04), of SLE in Chinese population. Polymorphisms of rs961616 in MAMDC1 gene were associated with rash and photosensitivity, but not disease risk, of systemic lupus erythematosus in Chinese population.

Evaluation of photopatch test allergens for Indian patients of photodermatitis: preliminary results.

BACKGROUND: There is a strong need to develop a photopatch test tray suitable for Indian patients of photodermatitis as European/Scandinavian photopatch test trays may not be wholly relevant for them. AIM: We carried out this study using photoallergens relevant in the Indian context to determine their relevance in patients of photodermatitis. METHODS: Thirty patients (M:F, 23:7) between 19 and 76 years of age of photodermatitis and 10 controls were patch- and photopatch tested with 20 common photoallergens. In addition, the patients were also (photo) patch tested with articles of daily use as and when these were suspected to be the cause. RESULTS: Forty-three positive reactions to one or more antigens were seen in 22 (74%) patients. Fourteen positive photopatch tests to seven allergens were observed in 10 (33%) patients, and nine (30%) of them had a definite relevance. The most common contact allergen was fragrance mix (FM) (30%), followed by p-phenylenediamine (20%) and Parthenium hysterophorous (17%). The definite relevance of the patch- and photopatch tests could be correlated in 47% of these patients. CONCLUSIONS: FM is the most common contact and photocontact allergen among the various photopatch test antigens. Although differences in technique and evaluation make direct comparison between different centers difficult, still photopatch testing remains an integral part and gold standard for the work-up of the photosensitive patients.

Chronic actinic prurigo presenting in an adopted child.

In diagnosing actinic prurigo (AP), the patients' ethnic background is very helpful as this condition is associated with very specific ethnic groups. We discuss a patient with an unknown family history who presented with a rash that initially seemed like lupus, but was subsequently diagnosed as AP upon further evaluations.

Actinic conjunctivitis in children: Clinical features, relation to sun exposure, and proposed staging and treatment.

BACKGROUND: Actinic conjunctivitis is an ocular photosensitivity reaction found mainly in children in certain populations in the Andean regions of South America, Mexico, and in the southwestern United States. Its clinical features, treatment, and possible relation to duration of sun exposure have not been fully described in the ophthalmologic literature. METHODS: A 20-member ophthalmic team traveled to an Andean region of Ecuador to provide ophthalmic care to children. All children with conjunctivitis were examined. A novel 3-stage classification of actinic conjunctivitis, devised by one of the authors, was used to stage the disease. The parents of each child with actinic conjunctivitis were asked how much time the child spent outside. Histopathological evaluations were performed on children who underwent surgery. RESULTS: A total of 206 children were examined, of whom 36 had changes consistent with actinic conjunctivitis. Stage 1 disease was diagnosed in 17 children, stage 2 in 9, and stage 3 in 10 in the most severely affected eye. The amount of time the child spent outside correlated with disease severity (r = 0.77, p < 0.001). Histopathologic samples showed an intense inflammatory response with hyperplasia of the vascular endothelium, pigmentary migration, and occasional eosinophilia. CONCLUSIONS: Actinic conjunctivitis is prevalent among children of the highlands of Ecuador. Although it has an allergic component, our data suggest that the severity of the disease is significantly associated with sun exposure. The finding that the lesions are found only in the exposed conjunctiva supports the hypothesis that UV exposure is the main cause of the disease.

Biochemical and molecular diagnosis of erythropoietic protoporphyria in an Ashkenazi Jewish family.

Erythropoietic protoporphyria (EPP) is a rare hereditary disorder due to a partial deficiency of ferrochelatase (FECH). The genotype of EPP patients features a mutation on one allele of the FECH gene and a common hypomorphic FECH IVS3-48c on the other allele (M/c). The resulting enzyme activity in patients is ∼35% of that in normal individuals. Ferrochelatase deficiency results in the accumulation of protoporphyrin in the skin, which is responsible for the clinical symptom of cutaneous photosensitivity in patients. In this study, we report the identification of a novel FECH mutation delT23 in an 11-member EPP family of Jewish origin. Two EPP siblings shared an identical genotype of delT23/IVS3-48c (M/c). They were both photosensitive and showed highly increased erythrocyte protoporphyrin. The genotype of the patients' mother, who did not present with any EPP clinical symptoms, was delT23/IVS3-48t (M/t). The patients' father, an offspring of consanguineous parents, was homozygous IVS3-48 c/c. He exhibited a mild photosensitivity, and an increase of 4-fold in erythrocyte protoporphyrin. His FECH mRNA amount was 71% of that of genotype t/t. It is the first reported case of an individual with c/c genotype who exhibits both biochemical and clinical indications of EPP. These results suggest that IVS3-48c is a functional variant of ferrochelatase. The clinical symptoms and biochemical abnormalities in the patients' father could be the result of an interaction between genetic and environmental factors. In addition, the frequency of IVS3-48c in the Ashkenazi Jewish population was estimated at 8%, which is similar to that in the European populations.

Lichen nitidus actinicus: a distinct facial presentation in 3 pre-pubertal African-American girls.

Lichen nitidus is a relatively common inflammatory disorder of uncertain etiology seen primarily in the pediatric population. A rare variant may demonstrate a photodistribution of characteristic lesions. We describe 3 cases of lichen nitidus actinicus with prominent facial lesions.

Analysis of photodermatoses seen in a predominantly Asian population at a photodermatology clinic in Singapore.

BACKGROUND: The idiopathic photodermatoses have been reported to be rarer in tropical Singapore than in countries of higher latitude, with photoaggravated dermatoses and systemic phototoxicity making up most of the photodermatoses seen here. This study aims to reassess the spectrum of photodermatoses seen at the National Skin Centre, Singapore, compared with almost a decade ago, and analyse the clinical and photobiological characteristics, as compared with other countries. MATERIALS AND METHODS: We reviewed the clinical data of 141 patients phototested from January 2000 to December 2001, and analysed the epidemiological, clinical and photobiological features. RESULTS: Photosensitive dermatoses were diagnosed in 88% (124/141) of patients phototested. In those diagnosed with photodermatoses, polymorphic light eruption (PMLE) (28%) was the most common diagnosis, followed by photoaggravated dermatoses (26%), chronic actinic dermatitis (CAD) (15%), systemic phototoxicity (15%), solar urticaria (SU) (7%), actinic prurigo (AP) (5%) and photoallergic contact dermatitis (4%). Ethnic Indians appeared to be more predisposed to PMLE; AP was diagnosed only in ethnic Chinese. The other photodermatoses occurred proportionally in all racial groups. AP differed from that found in Caucasians, being of adult onset and persistent. Abnormal phototest results were obtained in all patients with CAD, SU and AP, but only in 56% and 49% of systemic phototoxicity and PMLE, respectively. CONCLUSION: Idiopathic photodermatoses are more commonly diagnosed in Singapore than a decade ago, while the incidence of systemic phototoxicity has remained stable. The spectrum of photodermatoses in our Asian population now approximates that seen in Caucasian cohorts.

Evidence that thalidomide modifies the immune response of patients suffering from actinic prurigo.

BACKGROUND: Actinic prurigo (AP) is a photodermatosis with a restricted ethnic distribution, mainly affecting Mestizo women (mixed Indian and European). The lesions are polymorphic and include macules, papules, crusts, hyperpigmentation and lichenification. Thalidomide, an effective immunomodulatory drug, was first used successfully to treat AP in 1973. In this work we describe the effect that thalidomide had on TNF-alpha sera levels and on IL-4- and IFN gamma (IFNgamma)-producing lymphocytes of actinic prurigo (AP) patients. METHODS: Actinic prurigo patients were analyzed before and after thalidomide treatment. The percentage of IL-4+ or IFNgamma+ CD3+ lymphocytes was analyzed in eight of them by flow cytometry. TNFalpha in sera was measured by ELISA in 11 patients. RESULTS: A direct correlation was observed between resolution of AP lesions and an increase in IFNgamma+ CD3+ peripheral blood mononuclear cells (P < or = 0.001) and a decrease in TNFalpha serum levels (no statistical difference). No IL-4+ CD3+ cells were detected. CONCLUSIONS: Our findings confirm that AP is a disease that has an immunological component and that thalidomide clinical efficacy is exerted not only through inhibition of TNFalpha synthesis, but also through modulation of INFgamma-producing CD3+ cells. These cells could be used as clinical markers for recovery.

Photo-damage in Northern European renal transplant recipients is associated with use of calcium channel blockers.

Photo-damage of the head and neck was assessed, by visual inspection, in 82 Northern European renal transplant recipients attending a dermatology clinic. Photo-damage was graded as absent, mild, moderate and severe and the presence or absence of skin telangiectasia, solar elastosis, erythema and pigmentation was assessed. The duration and type of immunosuppressant and calcium channel blocker medication was recorded. Ninety percent had photo-damaged skin with 41 (50%) having mild photo-damage, 20 (24%) moderate photo-damage and 13 (16%) severe photo-damage. Sixty-two (76%) had pigmentation, 43 (52%) telangiectasia, 65 (79%) papular changes and 51 (65%) erythema. Fifty-three patients (65%) had received a calcium channel blocker (49 nifedipine, four amlodipine). The grade of photo-damage was strongly associated with use of calcium channel blockers (P=0.001) as was the presence of telangiectasia (P=0.001) and solar elastosis (P=0.04). Photo-damage is frequent in this population of renal transplant patients. Telangiectasia in association with calcium channel blockers has been reported rarely but appears to be common in the transplant population.

Actinic prurigo: clinical features and HLA associations in a Canadian Inuit population.

BACKGROUND: Actinic prurigo (AP) is an idiopathic familial photodermatitis. AP of the Inuit is rarely reported and poorly characterized. OBJECTIVE: Our purpose was to examine the clinical features and HLA associations of AP in an Inuit population. METHODS: Thirty-seven Inuit subjects with AP were administered a questionnaire and underwent a cutaneous examination. Other causes of photosensitivity were excluded. HLA class I typing was performed by polymerase chain reaction and sequence-specific primers and class II typing by polymerase chain reaction and sequence-specific oligonucleotide probes. RESULTS: Subjects were 81.1% female, 67.6% had a family history of photosensitivity, and all experienced seasonal variation. The average age at onset of photosensitivity was 29 years, and only 27% had a trend toward improvement in photosensitivity. Involvement of eyes and nonexposed skin was reported in 62.2% and 18.9% of subjects, respectively. Physical examination revealed involvement of the face (64.9%), lip (32.4%), ear (13.5%), and dorsal aspect of the hand (24.3%). HLA-DRB1*14 was present in 51.2% of subjects and 26.2% of controls (P =.022, odds ratio = 2.975). This is a previously unreported HLA association. CONCLUSION: AP in the Inuit is a seasonal, pruritic photodermatitis, often commencing in adulthood and worsening over time. A novel association with HLA-DRB1*14 has been discovered. Overall, this novel HLA association, the absence of HLA associations previously reported in non-Inuit populations, and clinical distinguishing features support the concept that AP in the Inuit may have a distinct immunopathogenic basis that translates into a different phenotype. It also raises the question of whether AP in the Inuit is a distinct photosensitivity disorder specific to this group that has been genetically isolated because of geographic and cultural seclusion.

Major gene segregation of actinic prurigo among North American Indians in Saskatchewan.

Actinic prurigo is an idiopathic, familial photodermatosis seen especially in American Indians. Segregation analysis was performed on 12 Saskatchewan pedigrees with American Indian ancestry, comprising a total of 1,148 individuals, ascertained via probands diagnosed with actinic prurigo. Although a high degree of familial aggregation has been noted in the past and dominant inheritance has been suggested, no formal segregation analysis has been attempted. Actinic prurigo has a variable age of onset and, therefore, age at the time of censoring must be taken into account in the analysis. However, as these ages of 57% of the unaffected individuals were missing, an algorithm was devised to impute the missing ages from known birth years in the family based on the age differences among relatives and spouses. Using these imputed ages, simple dominant inheritance with incomplete penetrance and a single age of onset distribution was found. The method for imputing the ages at examination was evaluated, as was the correction for ascertainment, by using alternative methods and comparing the results. Regardless of the method used, a dominant mode of inheritance without any multifactorial component remained the best hypothesis.