Hypohidrotic ectodermal dysplasia (HED), a congenital disorder of teeth, hair, and eccrine sweat glands, is usually inherited as an X-linked recessive trait, although rarer autosomal dominant and recessive forms exist. We have studied males from four families with HED and immunodeficiency (HED-ID), in which the disorder segregates as an X-linked recessive trait. Affected males manifest dysgammaglobulinemia and, despite therapy, have significant morbidity and mortality from recurrent infections. Recently, mutations in IKK-gamma (NEMO) have been shown to cause familial incontinentia pigmenti (IP). Unlike HED-ID, IP affects females and, with few exceptions, causes male prenatal lethality. IKK-gamma is required for the activation of the transcription factor known as "nuclear factor kappa B" and plays an important role in T and B cell function. We hypothesize that "milder" mutations at this locus may cause HED-ID. In all four families, sequence analysis reveals exon 10 mutations affecting the carboxy-terminal end of the IKK-gamma protein, a domain believed to connect the IKK signalsome complex to upstream activators. The findings define a new X-linked recessive immunodeficiency syndrome, distinct from other types of HED and immunodeficiency syndromes. The data provide further evidence that the development of ectodermal appendages is mediated through a tumor necrosis factor/tumor necrosis factor receptor-like signaling pathway, with the IKK signalsome complex playing a significant role.

INTRODUCTION: Acne vulgaris is one of the most common skin conditions in children and adolescents. The presentation, differential diagnosis, and association of acne with systemic pathology differs by age of presentation. Current acknowledged guidelines for the diagnosis and management of pediatric acne are lacking, and there are variations in management across the spectrum of primary and specialty care. The American Acne and Rosacea Society convened a panel of pediatric dermatologists, pediatricians, and dermatologists with expertise in acne to develop recommendations for the management of pediatric acne and evidence-based treatment algorithms. METHODS: Ten major topic areas in the diagnosis and treatment of pediatric acne were identified. A thorough literature search was performed and articles identified, reviewed, and assessed for evidence grading. Each topic area was assigned to 2 expert reviewers who developed and presented summaries and recommendations for critique and editing. Furthermore, the Strength of Recommendation Taxonomy, including ratings for the strength of recommendation for a body of evidence, was used throughout for the consensus recommendations for the evaluation and management of pediatric acne. Practical evidence-based treatment algorithms also were developed. RESULTS: Recommendations were put forth regarding the classification, diagnosis, evaluation, and management of pediatric acne, based on age and pubertal status. Treatment considerations include the use of over-the-counter products, topical benzoyl peroxide, topical retinoids, topical antibiotics, oral antibiotics, hormonal therapy, and isotretinoin. Simplified treatment algorithms and recommendations are presented in detail for adolescent, preadolescent, infantile, and neonatal acne. Other considerations, including psychosocial effects of acne, adherence to treatment regimens, and the role of diet and acne, also are discussed. CONCLUSIONS: These expert recommendations by the American Acne and Rosacea Society as reviewed and endorsed by the American Academy of Pediatrics constitute the first detailed, evidence-based clinical guidelines for the management of pediatric acne including issues of special concern when treating pediatric patients.

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Crouzon syndrome, an autosomal dominant condition characterized by craniosynostosis, ocular proptosis and midface hypoplasia, is associated with mutations in fibroblast growth factor receptor 2 (FGFR2) (refs 1-3). For example, we have identified 10 different mutations in the FGFR2 extracellular immunoglobulin III (IgIII) domain in 50% (16/32) of our Crouzon syndrome patients. All mutations described so far for other craniosynostotic syndromes with associated limb anomalies--Jackson-Weiss, Pfeiffer, and Apert--also occur in the extracellular domain of FGFR2, as well as FGFR1 for Pfeiffer syndrome. In contrast, only FGFR3 mutations have been reported in dwarfing conditions--achondroplasia, thanatophoric dysplasia, and hypochondroplasia. For achondroplasia, greater than 99% of mutations occur in the FGFR3 transmembrane domain. We now report the unexpected observation of a FGFR3 transmembrane domain mutation, Ala391Glu, in three unrelated families with Crouzon syndrome and acanthosis nigricans, a specific skin disorder of hyperkeratosis and hyperpigmentation. The association of non-dwarfing and even non-skeletal conditions with FGFR3 mutations reveals the potential for a wide range of FGFR pleiotropic effects as well as locus heterogeneity in Crouzon syndrome. Our study underscores the biologic complexity of the FGFR gene family.

Background Patients with atopic dermatitis (AD) are prone to skin infections, with microbes like Staphylococcus aureus suspected of contributing to pathogenesis. Bleach baths might improve AD by reducing skin microbial burden. Objective To characterize the microbiota of lesional and nonlesional skin in young children with AD and controls and compare changes after treatment with a topical corticosteroid (TCS) alone or TCS + dilute bleach baths (BB). Methods In a randomized, placebo-controlled, single-blinded clinical trial in 21 children with AD and 14 healthy children, lesional and nonlesional AD skin was examined at baseline and after 4-week treatment with TCS alone or TCS plus BB. Microbial DNA was extracted for qPCR of predominant genera and 16S rRNA sequencing. Results At baseline, densities of total bacteria and Staphylococcus, including S. aureus, were significantly higher at the worst AD lesional site than nonlesional (p=0.001) or control (p<0.001) skin; bacterial communities on lesional and nonlesional AD skin significantly differed from each other (p=0.04) and from control (p<0.001). After TCS + BB or TCS alone, bacterial compositions on lesional skin normalized (p<0.0001), resembling nonlesional skin, with microbial diversity restored to control skin levels. Limitations The 4-week time period and/or the twice-weekly baths may not have been sufficient for additional impact on the cutaneous microbiome. More detailed sequencing may allow better characterization of the distinguishing taxa with BB-treatment. Conclusions Treatment with a topical corticosteroid cream suffices to normalize the cutaneous microbiota on lesional AD; after treatment, bacterial communities on lesional skin resemble nonlesional skin but remain distinct from control.

Inflammation-associated pigmentation changes are extremely common, but the etiology behind this clinical observation remains elusive. Particularly, it is unclear how the myriad of cytokines known to be involved in inflammatory skin processes affect epidermal melanocytes. We sought to determine how IL-17 and TNF influence normal human melanocytes, as these two cytokines have been implicated in various skin diseases. IL-17 and TNF jointly stimulated broad inductions of cytokines , including melanoma mitogens CXCL1 and IL-8. Moreover, IL-17 and TNF synergistically inhibited pigmentation-related signaling and melanin production, and induced keratinocytes production of β-defensin 3, an antagonist for melanocortin-receptor 1. When analyzing psoriasis lesions that are known to over express IL-17 and TNF, we observed an increase in melanocyte number and a simultaneous decrease in pigmentation signaling. Furthermore, therapeutic neutralization of TNF and IL-17 with mAbs results in a rapid recovery of pigment gene expression in psoriasis lesions. These results demonstrate that IL-17 and TNF can impact both the growth and pigment production of melanocytes, which may contribute to the pigmentation changes associated with psoriasis. These findings may allow the development of novel therapeutics for pigmentary disorders and bring new insights into the immune milieu surrounding melanocytes and related neoplasms.

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Vitiligo is characterized by depigmented skin patches due to loss of epidermal melanocytes. Oxidative stress may play a role in vitiligo onset, while autoimmunity contributes to disease progression. In this study we sought to identify mechanisms that link disease triggers and spreading of lesions. A hallmark of melanocytes at the periphery of vitiligo lesions is dilation of the endoplasmic reticulum (ER). We hypothesized that oxidative stress results in redox disruptions that extend to the ER, causing accumulation of misfolded peptides, which activates the unfolded protein response (UPR). We used 4-tertiary butyl phenol (4-TBP) and monobenzyl ether of hydroquinone (MBEH), known triggers of vitiligo. We show that expression of key UPR components, including the transcription factor X-box binding protein 1 (XBP1), are increased following exposure of melanocytes to phenols. XBP1 activation increases production of immune mediators interleukin-6 (IL6) and IL8. Co-treatment with XBP1 inhibitors reduced IL6 and IL8 production induced by phenols, while over-expression of XBP1 alone increased their expression. Thus, melanocytes themselves produce cytokines associated with activation of an immune response following exposure to chemical triggers of vitiligo. These results expand our understanding of the mechanisms underlying melanocyte loss in vitiligo and pathways linking environmental stressors and autoimmunity.