Macrophage-Mediated Phagocytosis and Dissolution of Amyloid-Like Fibrils in Mice, Monitored by Optical Imaging.

Light chain-associated amyloidosis is characterized by the extracellular deposition of amyloid fibrils in abdominothoracic organs, skin, soft tissue, and peripheral nerves. Phagocytic cells of the innate immune system appear to be ineffective at clearing the material; however, human light chain amyloid extract, injected subcutaneously into mice, is rapidly cleared in a process that requires neutrophil activity. To better elucidate the phagocytosis of light chain fibrils, a potential method of cell-mediated dissolution, amyloid-like fibrils were labeled with the pH-sensitive dye pHrodo red and a near infrared fluorophore. After injecting this material subcutaneously in mice, optical imaging was used to quantitatively monitor phagocytosis and dissolution of fibrils concurrently. Histologic evaluation of the residual fibril masses revealed the presence of CD68+, F4/80+, ionized calcium binding adaptor molecule 1- macrophages containing Congo red-stained fibrils as well as neutrophil-associated proteins with no evidence of intact neutrophils. These data suggest an early infiltration of neutrophils, followed by extensive phagocytosis of the light chain fibrils by macrophages, leading to dissolution of the mass. Optical imaging of this novel murine model, coupled with histologic evaluation, can be used to study the cellular mechanisms underlying dissolution of synthetic amyloid-like fibrils and human amyloid extracts. In addition, it may serve as a test bed to evaluate investigational opsonizing agents that might serve as therapeutic agents for light chain-associated amyloidosis.

Society of Dermatology Hospitalists supportive care guidelines for the management of Stevens-Johnson syndrome/toxic epidermal necrolysis in adults.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening conditions with high morbidity and mortality. Supportive care management of SJS/TEN is highly variable. A systematic review of the literature was performed by dermatologists, ophthalmologists, intensivists, and gynecologists with expertise in SJS/TEN to generate statements for supportive care guideline development. Members of the Society of Dermatology Hospitalists with expertise in SJS/TEN were invited to participate in a modified, online Delphi-consensus. Participants were administered 9-point Likert scale questionnaires regarding 135 statements. The RAND/UCLA Appropriateness Method was used to evaluate and select proposed statements for guideline inclusion; statements with median ratings of 6.5 to 9 and a disagreement index of ≤1 were included in the guideline. For the final round, the guidelines were appraised by all of the participants. Included are an evidence-based discussion and recommendations for hospital setting and care team, wound care, ocular care, oral care, urogenital care, pain management, infection surveillance, fluid and electrolyte management, nutrition and stress ulcer prophylaxis, airway management, and anticoagulation in adult patients with SJS/TEN.

Distinguishing Stevens-Johnson syndrome/toxic epidermal necrolysis from clinical mimickers during inpatient dermatologic consultation-A retrospective chart review.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening conditions that may present with similar findings to other severe dermatologic diseases. OBJECTIVE: The primary objective of this exploratory study was to explore factors associated with SJS/TEN and develop a model that provides the predicted probability of SJS/TEN for patients for whom the diagnosis of SJS/TEN is considered. METHODS: Retrospective review of consultations for patients with suspected SJS, TEN, or overlap at 4 academic dermatology consultation services. RESULTS: Overall, 208 patients were included; 59 (28.4%) had a final diagnosis of SJS/TEN, and 149 (71.6%) were given a different diagnosis. The most common mimickers were drug hypersensitivity syndrome (n = 21, 10.1%), morbilliform drug eruption (n = 18, 8.7%), erythema multiforme (n = 15, 7.2%), and acute generalized exanthematous pustulosis (n = 13, 6.2%). Nikolsky sign, atypical targets, fever, and lymphopenia were included in a model for predicting the probability of SJS/TEN. LIMITATIONS: All cases were obtained from academic centers, which may limit the generalization of findings to community-based settings. This was an exploratory study with a small number of cases, and external validation of the model performance is needed. CONCLUSION: Early dermatologic evaluation of patients with suspected SJS/TEN is key to separating patients with this condition from those who ultimately receive diagnoses of other serious skin diseases.

Inhibition of interleukin-12 and/or interleukin-23 for the treatment of psoriasis: What is the evidence for an effect on malignancy?

Immune cells and cytokines play an important role in the pathogenesis of psoriasis. Interleukin-12 (IL-12) and IL-23 promote cellular responses mediated by T cells, which contribute to an inflammatory loop responsible for the induction and maintenance of psoriatic plaques. Antibodies that inhibit IL-12/23 or IL-23 are key treatment options for patients with psoriasis. IL-12 and IL-23 also play a key role in immune responses to infections and tumors. A growing body of information from clinical trials, cohort studies, postmarketing reports, genetic studies and animal models provides insights into the potential biological relationships between IL-12/23 inhibition and malignancies. We summarize this information in tables and provide some context for the interpretation of these data with the goal of informing dermatologists who are using IL-12/23 or IL-23 inhibitors to treat patients with psoriasis.

Is non-alcoholic steatohepatitis a predisposing factor to porphyria cutanea tarda?

Porphyria cutanea tarda (PCT) is a disease caused by a deficiency of the fifth enzyme of the heme biosynthetic pathway in the liver that manifests in the skin as blistering and fragility of predominantly sun-exposed skin. It occurs in individuals with environmental and/or genetic risk factors such as estrogen use, hepatitis C infection and hemochromatosis gene mutations. This report highlights a case of PCT which manifested in an individual with non-alcoholic fatty liver disease (non-alcoholic steatohepatitis; NASH). We propose that NASH may have been a contributing factor for the development of PCT in our patient.

SJS/TEN 2017: Building Multidisciplinary Networks to Drive Science and Translation.

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a life-threatening, immunologically mediated, and usually drug-induced disease with a high burden to individuals, their families, and society with an annual incidence of 1 to 5 per 1,000,000. To effect significant reduction in short- and long-term morbidity and mortality, and advance clinical care and research, coordination of multiple medical, surgical, behavioral, and basic scientific disciplines is required. On March 2, 2017, an investigator-driven meeting was held immediately before the American Academy of Dermatology Annual meeting for the central purpose of assembling, for the first time in the United States, clinicians and scientists from multiple disciplines involved in SJS/TEN clinical care and basic science research. As a product of this meeting, this article summarizes the current state of knowledge and expert opinion related to SJS/TEN covering a broad spectrum of topics including epidemiology and pharmacogenomic networks; clinical management and complications; special populations such as pediatrics, the elderly, and pregnant women; regulatory issues and the electronic health record; new agents that cause SJS/TEN; pharmacogenomics and immunopathogenesis; and the patient perspective. Goals include the maintenance of a durable and productive multidisciplinary network that will significantly further scientific progress and translation into prevention, early diagnosis, and management of SJS/TEN.