Contact dermatitis: one for the books.

Allergic contact dermatitis (ACD) is a frequent problem, often caused from repeated exposure to an object or substance related to the patient's routine activities. We present a case of a well-demarcated, erythematous, scaly plaque on a finger caused from reading with an e-book device. Although metal from mobile devices can cause ACD, mobile device cases may cause irritation or contain additives that can also cause contact dermatitis. Similar presentations of contact dermatitis may become more common as technology use increases.

Hypopigmented Macules as Manifestation of Lichen Planus and Lichen Planopilaris.

Lichen planus (LP) is an idiopathic inflammatory disease of the skin, hair, nails, and mucous membranes. Classic cutaneous LP is characterized by violaceous flat-topped papules that typically favor the extremities. LP on the scalp, otherwise known as lichen planopilaris, classically presents with scarring alopecia, perifollicular erythema and follicular prominence. Although LP pigmentosus presents primarily as hyperpigmentation, there is only one previous report of hypopigmented LP. In this report, the authors report 2 cases of LP that presented primarily as hypopigmented macules in 2 African American men. The first patient presented with hypopigmented macules on face and scalp as well as trunk and extremities. The second patient presented with hypopigmented macules on scalp with associated alopecia. Histopathological examination from both patients showed features of LP. The authors propose a new variant of LP that presents acutely as hypopigmented lesions.

Rituximab Use in Pediatric Dermatology.

Rituximab, an anti CD20 monoclonal antibody leading to transitory B cell depletion, is used to treat a wide variety of immune system tumors and immune mediated diseases. While most of data supporting the efficacy and safety of rituximab in treating autoimmune patients is focused on the adult population, the utilization of rituximab (RTX) for a wide range of pediatric conditions is also increasing. While there are a number of published case reports, a comprehensive review of the various uses for rituximab in pediatric dermatology is lacking. To better assess the therapeutic role of rituximab in the management of skin disease in children, here we comprehensively document reported cases of use including details regarding specific treatment regimens, efficacy and safety profile. Evaluation of the data supports consideration for the initiation of rituximab at early time points in the treatment ladder, before certain diseases become refractory to conventional treatment.

J Drugs Dermatol. 2016;15(7):821-829.

Current challenges and emerging drug delivery strategies for the treatment of psoriasis.

INTRODUCTION: Psoriasis is a common skin disorder associated with physical, social, psychological and financial burden. Over the past two decades, advances in our understanding of pathogenesis and increased appreciation for the multifaceted burden of psoriasis has led to new treatment development and better patient outcomes. Yet, surveys demonstrate that many psoriasis patients are either undertreated or are dissatisfied with treatment. There are many barriers that need be overcome to optimize patient outcomes and satisfaction. AREAS COVERED: This review covers the current challenges associated with each major psoriasis treatment strategy (topical, phototherapy, oral medications and biologics). It also reviews the challenges associated with the psychosocial aspects of the disease and how they affect treatment outcomes. Patient adherence, inconvenience, high costs, and drug toxicities are all discussed. Then, we review the emerging drug delivery strategies in topical, oral, and biologic therapy. EXPERT OPINION: By outlining current treatment challenges and emerging drug delivery strategies, we hope to highlight the deficits in psoriasis treatment and strategies for how to overcome them. Regardless of disease severity, clinicians should use a patient-centered approach. In all cases, we need to balance patients' psychosocial needs, treatment costs, convenience, and effectiveness with patients' preferences in order to optimize treatment outcomes.

Psoriasis during pregnancy: characteristics and important management recommendations.

The treatment of psoriasis in pregnant women can be challenging. Psoriasis generally improves during pregnancy; however, many pregnant patients still require treatment. In treating pregnant patients, the benefits of treatment and risks to the mother and the fetus must be considered. For localized psoriasis, topical corticosteroids are the treatment of choice. Other topical agents that are approved for the treatment of psoriasis, such as topical tar products and topical tazarotene, should be avoided during pregnancy because of unclear risks of teratogenicity. For moderate-to-severe psoriasis, ultraviolet B phototherapy is preferred. Despite limited safety data, biologics are favored over other systemic medications when needed. While there are new treatment options for psoriasis, there is limited information on the safety of medications during pregnancy.

Pemphigus vulgaris: approach to treatment.

The therapeutic management of pemphigus vulgaris (PV) is centered around immunosuppression, which can be generalized, as in the use of corticosteroids or steroid sparing agents, or specific, as in therapeutic blockage of autoantibody production, certain cytokines, or signaling pathways. Currently, the backbone of treatment for PV, particularly, first line therapy, remains systemic corticosteroids. Although very effective, the significant side effects of long-term corticosteroid usage are well documented. Adjunctive therapies aim to eliminate, or at least decrease, the necessary dose of corticosteroids. Specifically, azathioprine, cyclophosphamide, methotrexate, cyclosporine, mycophenolate mofetil and dapsone are now widely used in PV. Intravenous immunoglobulin (IVIG), plasmapheresis, immunoadsorption, and most recently, rituximab, are other members of the therapeutic armamentarium. However, despite the widening range of treatment options in PV, well-controlled clinical trials and consensus guidelines are lacking.

The functional model complex [Fe2(BPMP)(OPr)(NO)2](BPh4)2 provides insight into the mechanism of flavodiiron NO reductases.

Flavodiiron nitric oxide reductases (FNORs), found in many pathogenic bacteria, are able to detoxify NO by reducing it to N2O. In this way, FNORs equip these pathogens with immunity to NO, which is a central immune defense agent in humans. Hence, FNORs are thought to promote infection of the human body, leading to chronic diseases. Despite this importance of FNORs for bacterial pathogenesis, the mechanism of NO reduction by these enzymes is not well understood. Here we present the synthesis and spectroscopic characterization of the diiron dinitrosyl model complex [Fe2(BPMP)(OPr)(NO)2](BPh4)2. The crystal structure of this complex shows two end-on-coordinated {FeNO}(7) units that, based on spectroscopic and electrochemical results, are only weakly electronically coupled. Importantly, reduction of this complex by two electrons leads to the clean formation of N2O in quantitative yield. This complex therefore represents the first example of a functional model system for FNORs. The results provide key mechanistic insight into the mechanism of FNORs and, in particular, represent strong support for the proposed "super-reduced" mechanism for these enzymes.

Structural and electronic characterization of non-heme Fe(II)-nitrosyls as biomimetic models of the Fe(B) center of bacterial nitric oxide reductase.

The detoxification of nitric oxide (NO) by bacterial NO reductase (NorBC) has gained much attention as this reaction provides a paradigm as to how NO can be detoxified anaerobically in cells. However, a clear mechanistic picture of how the heme/non-heme active site of NorBC activates NO is lacking, mostly as a result of insufficient knowledge about the properties of the non-heme iron(II)-NO adduct. Here we report the first biomimetic model complexes for this species that closely resemble the coordination environment found in the protein, using the ligands BMPA-Pr and TPA. The systematic investigation of these compounds allowed us to gain key insight into the electronic structure and geometric properties of high-spin non-heme iron(II)-NO adducts. In particular, we show how small changes in the ligand environment of iron could be used by NorBC to greatly modulate the properties, and hence, the reactivity of this species.