Wake Forest University

Perioperative Considerations for a Patient with Alpha-Gal Syndrome Undergoing Cardiac Surgery.

Mechanisms Governing Anaphylaxis: Inflammatory Cells, Mediators, Endothelial Gap Junctions and Beyond.

Anaphylaxis is a severe, acute, life-threatening multisystem allergic reaction resulting from the release of a plethora of mediators from mast cells culminating in serious respiratory, cardiovascular and mucocutaneous manifestations that can be fatal. Medications, foods, latex, exercise, hormones (progesterone), and clonal mast cell disorders may be responsible. More recently, novel syndromes such as delayed reactions to red meat and hereditary alpha tryptasemia have been described. Anaphylaxis manifests as sudden onset urticaria, pruritus, flushing, erythema, angioedema (lips, tongue, airways, periphery), myocardial dysfunction (hypovolemia, distributive or mixed shock and arrhythmias), rhinitis, wheezing and stridor. Vomiting, diarrhea, scrotal edema, uterine cramps, vaginal bleeding, urinary incontinence, dizziness, seizures, confusion, and syncope may occur. The traditional (or classical) pathway is mediated via T cells, Th2 cytokines (such as IL-4 and 5), B cell production of IgE and subsequent crosslinking of the high affinity IgE receptor (FcεRI) on mast cells and basophils by IgE-antigen complexes, culminating in mast cell and basophil degranulation. Degranulation results in the release of preformed mediators (histamine, heparin, tryptase, chymase, carboxypeptidase, cathepsin G and tumor necrosis factor alpha (TNF-α), and of de novo synthesized ones such as lipid mediators (cysteinyl leukotrienes), platelet activating factor (PAF), cytokines and growth factors such as vascular endothelial growth factor (VEGF). Of these, histamine, tryptase, cathepsin G, TNF-α, LTC, PAF and VEGF can increase vascular permeability. Recent data suggest that mast cell-derived histamine and PAF can activate nitric oxide production from endothelium and set into motion a signaling cascade that leads to dilatation of blood vessels and dysfunction of the endothelial barrier. The latter, characterized by the opening of adherens junctions, leads to increased capillary permeability and fluid extravasation. These changes contribute to airway edema, hypovolemia, and distributive shock, with potentially fatal consequences. In this review, besides mechanisms (endotypes) underlying IgE-mediated anaphylaxis, we also provide a brief overview of IgG-, complement-, contact system-, cytokine- and mast cell-mediated reactions that can result in phenotypes resembling IgE-mediated anaphylaxis. Such classifications can lead the way to precision medicine approaches to the management of this complex disease.

Phase II study of cisplatin plus cetuximab in advanced, recurrent, and previously treated cancers of the cervix and evaluation of epidermal growth factor receptor immunohistochemical expression: a Gynecologic Oncology Group study.

The purpose of this study was to evaluate the safety and efficacy of cetuximab (C225), an antibody that inhibits epidermal growth factor receptor (EGFR) activity, with cisplatin and to explore associations between EGFR protein expression with patient demographics or clinical outcome. Women with advanced, persistent, or recurrent carcinoma of the cervix were eligible. The women received cisplatin at 30mg/m(2) on days 1 and 8 with a loading dose of cetuximab at 400mg/m(2) followed by 250mg/m(2) on days 1, 8, and 15 in a 21day cycle. Adverse events were assessed with CTCAE v 3.0. Primary measure of efficacy was tumor response by RECIST. The study was stratified by prior chemotherapy (CT). EGFR protein expression in pre-treatment tumor was analyzed by immunohistochemistry. Between September 2004 and March 2008, 76 patients were enrolled. Of these, 69 were eligible and evaluable; 44 (64%) received prior chemotherapy. There were 4 responses in each group, prior chemotherapy and no chemotherapy, 9% and 16%, respectively. Grade 4 toxicities included anemia (1), allergy (1), metabolic (1), and vascular (1). The most common grade 3 toxicities were metabolic (15), dermatologic (8), fatigue (6), and gastrointestinal (6). EGFR protein was expressed in 47/48 (98%) of tumors analyzed with a median cellular expression of 81%. Exploratory analyses revealed a trend between the percentage of cells expressing EGFR protein and PFS (hazard ratio=1.76, 95% confidence interval=0.96-3.21). The combination of cetuximab with cisplatin was adequately tolerated but did not indicate additional benefit beyond cisplatin therapy.