Dennis K. Ledford
University of South Florida
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World Allergy Organization Journal | 2011
F. Estelle R. Simons; Ledit Ardusso; M. Beatrice Bilò; Yehia M. El-Gamal; Dennis K. Ledford; Johannes Ring; Mario Sánchez-Borges; Gian Enrico Senna; Aziz Sheikh; Bernard Yu-Hor Thong
The illustrated World Allergy Organization (WAO) Anaphylaxis Guidelines were created in response to absence of global guidelines for anaphylaxis. Uniquely, before they were developed, lack of worldwide availability of essentials for the diagnosis and treatment of anaphylaxis was documented. They incorporate contributions from more than 100 allergy/immunology specialists on 6 continents. Recommendations are based on the best evidence available, supported by references published to the end of December 2010.The Guidelines review patient risk factors for severe or fatal anaphylaxis, co-factors that amplify anaphylaxis, and anaphylaxis in vulnerable patients, including pregnant women, infants, the elderly, and those with cardiovascular disease. They focus on the supreme importance of making a prompt clinical diagnosis and on the basic initial treatment that is urgently needed and should be possible even in a low resource environment. This involves having a written emergency protocol and rehearsing it regularly; then, as soon as anaphylaxis is diagnosed, promptly and simultaneously calling for help, injecting epinephrine (adrenaline) intramuscularly, and placing the patient on the back or in a position of comfort with the lower extremities elevated. When indicated, additional critically important steps include administering supplemental oxygen and maintaining the airway, establishing intravenous access and giving fluid resuscitation, and initiating cardiopulmonary resuscitation with continuous chest compressions. Vital signs and cardiorespiratory status should be monitored frequently and regularly (preferably, continuously).The Guidelines briefly review management of anaphylaxis refractory to basic initial treatment. They also emphasize preparation of the patient for self-treatment of anaphylaxis recurrences in the community, confirmation of anaphylaxis triggers, and prevention of recurrences through trigger avoidance and immunomodulation. Novel strategies for dissemination and implementation are summarized. A global agenda for anaphylaxis research is proposed.
World Allergy Organization Journal | 2009
G. Walter Canonica; Jean Bousquet; Thomas Casale; Richard F. Lockey; Carlos E. Baena-Cagnani; Ruby Pawankar; Paul C. Potter; Philippe Jean Bousquet; Linda Cox; Stephen R Durham; Harold S. Nelson; Giovanni Passalacqua; Dermot Ryan; Jan Brozek; Enrico Compalati; Ronald Dahl; Luís Delgado; Roy Gerth van Wijk; Richard G. Gower; Dennis K. Ledford; Nelson Augusto Rosário Filho; E. Valovirta; O. M. Yusuf; Torsten Zuberbier; Wahiduzzaman Akhanda; Raúl Lázaro Castro Almarales; Ignacio J. Ansotegui; Floriano Bonifazi; Jan Ceuppens; Tomás Chivato
Chair: G. Walter Canonica Co-Chairs Jean Bousquet, Thomas Casale, Richard F. Lockey, Carlos E. Baena-Cagnani, Ruby Pawankar, Paul C. Potter Authors Philippe J. Bousquet, Linda S. Cox, Stephen R. Durham, Harold S. Nelson, Giovanni Passalacqua, Dermot P. Ryan, Jan L. Brozek, Enrico Compalati, Ronald Dahl, Luis Delgado, Roy Gerth van Wijk, Richard G. Gower, Dennis K. Ledford, Nelson Rosario Filho, Erkka J. Valovirta, Osman M. Yusuf, Torsten Zuberbier Co-Authors Wahiduzzaman Akhanda, Raul Castro Almarales, Ignacio Ansotegui, Floriano Bonifazi, Jan Ceuppens, Tomás Chivato, Darina Dimova, Diana Dumitrascu, Luigi Fontana, Constance H. Katelaris, Ranbir Kaulsay, Piotr Kuna, Désirée Larenas-Linnemann, Manolis Manoussakis, Kristof Nekam, Carlos Nunes, Robyn O’Hehir, José M. Olaguibel, Nerin Bahceciler Onder, Jung Won Park, Alfred Priftanji, Robert Puy, Luis Sarmiento, Glenis Scadding, Peter Schmid-Grendelmeier, Ester Seberova, Revaz Sepiashvili, Dírceu Solé, Alkis Togias, Carlo Tomino, Elina Toskala, Hugo Van Beever, Stefan Vieths
Journal of Clinical Investigation | 1997
Kwang-Ho In; Koichiro Asano; David R. Beier; James K. Grobholz; Patricia W. Finn; Edwin K. Silverman; Eric S. Silverman; Tucker Collins; Annegret Fischer; T P Keith; Kristina Serino; S W Kim; G T De Sanctis; Chandri N. Yandava; A. Pillari; Paul H. Rubin; James P. Kemp; E Israel; William W. Busse; Dennis K. Ledford; John J. Murray; Allen T. Segal; D Tinkleman; Jeffrey M. Drazen
Five lipoxygenase (5-LO) is the first committed enzyme in the metabolic pathway leading to the synthesis of the leukotrienes. We examined genomic DNA isolated from 25 normal subjects and 31 patients with asthma (6 of whom had aspirin-sensitive asthma) for mutations in the known transcription factor binding regions and the protein encoding region of the 5-LO gene. A family of mutations in the G + C-rich transcription factor binding region was identified consisting of the deletion of one, deletion of two, or addition of one zinc finger (Sp1/Egr-1) binding sites in the region 176 to 147 bp upstream from the ATG translation start site where there are normally 5 Sp1 binding motifs in tandem. Reporter gene activity directed by any of the mutant forms of the transcription factor binding region was significantly (P < 0.05) less effective than the activity driven by the wild type transcription factor binding region. Electrophoretic mobility shift assays (EMSAs) demonstrated the capacity of wild type and mutant transcription factor binding regions to bind nuclear extracts from human umbilical vein endothelial cells (HUVECs). These data are consistent with a family of mutations in the 5-LO gene that can modify reporter gene transcription possibly through differences in Sp1 and Egr-1 transactivation.
The Journal of Allergy and Clinical Immunology | 2011
F. Estelle R. Simons; Ledit Ardusso; M. Beatrice Bilò; Yehia M. El-Gamal; Dennis K. Ledford; Johannes Ring; Mario Sánchez-Borges; Gian Enrico Senna; Aziz Sheikh; Bernard Yu-Hor Thong
The uniqueWorld Allergy Organization (WAO) Guidelines for the Assessment and Management of Anaphylaxis were created in response to the absence of global guidelines for anaphylaxis. They were developed after documenting that essential medications, supplies, and equipment for assessment andmanagement of anaphylaxis are not universally available worldwide. Additionally, they were developed with the awareness that any health care professional might, at some time, have to assess and manage anaphylaxis in a low-resource environment, whether this be a country, a region, or a specific location, such as an aircraft cabin or a remote area. They incorporate contributions frommore than 100 allergy/immunology specialists on 6 continents received through the WAO member societies and the WAO Board of Directors. In order to transcend language barriers, the principles of anaphylaxis assessment and management set forth in the guidelines are summarized in 5 comprehensive illustrations. The guidelines review patients’ risk factors for severe or fatal anaphylaxis, cofactors that amplify anaphylaxis, and anaphylaxis in vulnerable patients, such as pregnant women, infants, and the
Annals of Internal Medicine | 1993
Elliot Israel; Paul Rubin; James P. Kemp; Jay Grossman; William Pierson; Sheldon C. Siegel; David Tinkelman; John J. Murray; William W. Busse; Allen T. Segal; James E. Fish; Harold B. Kaiser; Dennis K. Ledford; Sally E. Wenzel; Richard R. Rosenthal; Judith Cohn; Carmine Lanni; Helene Pearlman; Peter Karahalios; Jeffrey M. Drazen
Although intermittent episodic airway narrowing occurs in persons with asthma, the biochemical basis of this obstruction has not been elucidated. Nonetheless, inflammatory cells present in the airways of persons with asthma [1, 2] release various substances that narrow airways. Among these are cysteinyl leukotrienes, which are formed from arachidonic acid in part by the enzyme 5-lipoxygenase [3]. The evidence favoring a role for leukotrienes in asthma is that they are produced by various airway cells including eosinophils and mast cells [4, 5], they are potent bronchoconstrictor agonists [6-8], and they can be recovered from biological fluids during asthma attacks [9-11]. Recently, the salutary effects of specific leukotriene-receptor antagonists or synthesis inhibitors in persons with asthma have suggested that interventions in the 5-lipoxygenase pathway may be of therapeutic use in the treatment of asthma [12-20]. These observations are particularly interesting because of the increasing concerns about asthma therapies such as -agonists and theophylline [21-24] and the known toxicity of long-term steroid use [25, 26]. However, the conclusions about the efficacy of these new drugs in persons with asthma largely derive from studies in laboratory-induced, rather than spontaneously occurring, asthma. Because cases of spontaneously occurring asthma may differ from those of laboratory-induced asthma, in mechanism or in response to therapy, we examined the effects of zileuton (N-1-[benzo(b)thien-2-ylethyl]-N-hydroxyurea), an investigational inhibitor of 5-lipoxygenase [27] currently in phase III trials of efficacy, in persons with asthma. In a double-blind, placebo-controlled trial in patients with mild-to-moderate airflow obstruction, we investigated the effects of inhibition of 5-lipoxygenase with zileuton (Leutrol; Abbott Laboratories, North Chicago, Illinois), during a 4-week period, on airway function, asthma symptoms, and the bronchodilator response to -agonists. We found that a dose of 600 mg four times per day (2.4 g/d), which produces more than 35% inhibition of leukotriene production as indicated by excretion of leukotriene E4 (LTE4) in the urine, had a salutary effect on airway function and asthma symptoms. Methods Patient Selection Patients with mild-to-moderate asthma were recruited at 14 centers, which included university hospitals and private allergy and pulmonary practices. Patients with symptoms that corresponded with the American Thoracic Society definition of asthma [28] were screened. All patients had to have a forced expiratory volume in 1 second (FEV1) of 40% to 75% of predicted value and a 15% or greater increase in FEV1 30 minutes after inhalation of two puffs of albuterol. Additionally, patients were required to be 18 to 65 years old; women of childbearing potential were excluded. Before enrollment in the study, none of the patients had used oral or inhaled steroids or cromolyn sodium for 4 weeks. Beta-blockers, calcium-channel blockers, and nonsteroidal anti-inflammatory drugs could not have been used for at least 1 week before entry into the study. All patients were required to be able to achieve adequate symptomatic asthma control without using theophylline, oral -agonists, or antihistamines; none of these medications was permitted throughout the entire study period. Study Design and Intervention A randomized parallel design was used in this double-blind, placebo-controlled study. Patients were chosen randomly to receive either 600 mg of zileuton (four times a day), 800 mg of zileuton (twice a day), or placebo. A 1-week, single-blind, placebo lead-in qualification period (dummy lead-in period) was followed by random allocation to one of the three treatment groups for a 4-week, double-blind phase. During the single-blind, dummy lead-in and the double-blind study periods, all patients took capsules four times a day. Self-determined peak expiratory flow rates were recorded in the morning (before medication) and evening (2 hours after the third set of capsules) in a study diary. Albuterol inhaler use and asthma symptoms were recorded in the diary as well. Daytime asthma symptoms were self-rated on a scale of 1 to 5 (1 = no symptoms, 5 = severe symptoms; maximum weekly score of 35). After the 1-week dummy lead-in period, patients returned to their study center. Inhaled albuterol was withheld for at least 8 hours before the study visit. Spirometry was done on patients who had no clinically significant laboratory abnormalities, who had successfully completed their diary card, who had moderately symptomatic asthma (a total score of 12 but 28 in the previous 7 days), and who had used their albuterol inhaler at least 7 times during the dummy lead-in week. If the FEV1 was 40% to 75% of the predicted value, the patient was assigned randomly to a group according to a predetermined code. All patients took visually identical capsules four times per day that contained either 600 mg of zileuton four times daily, 800 mg of zileuton twice daily (active drug first and last dose daily), or placebo, which were supplied by Abbott Laboratories in a blind manner. The first dose of study medication was administered at the study center, and spirometry was done 30, 60, and 120 minutes later. In the 800-mg group, each days drug card contained both placebo and active drug, and as a result, on the first day, an undetermined number of patients received placebo instead of 800 mg of zileuton as their first dose of drug. Therefore, the 800-mg group was not included in the analysis of the acute response to the first dose of drug. During the 4-week double-blind period, patients returned to the study center at the same time of day on a weekly basis to have spirometry done and to review diary cards and medication use. During the second and third weeks of the double-blind randomization period, spirometry was also repeated 30 minutes after inhalation of two puffs of albuterol. Urine Collection and Analysis Urine was collected for 4 hours beginning at 8:00 a.m. before the dummy lead-in period and on day 28 of the study. Urinary LTE4 levels were determined by reverse-phase high-performance liquid chromatography and enzyme immunoassay using minor modifications of established procedures [29]. The recovery of the internal LTE4 standard was 74% 6%. The LTE4 content of the urine was expressed as picograms of immunoreactive LTE4 per milligram of creatinine. Adverse Events Routine complete blood counts, serum chemistries, urinalyses, and electrocardiograms were obtained throughout the study. Adverse symptoms were elicited daily through a diary question and were reviewed at the weekly visit to the study site. Statistical Analysis All values were expressed as means with associated 95% CIs; all outcome indicators were normally distributed. Paired t-tests were used to assess the statistical significance of any within-group changes from the baseline dummy lead-in phase. The statistical significance of differences among the placebo and active treatment groups during the 4 weeks of double-blind treatment was evaluated using a two-way analysis of variance model with effects for center, treatment, and center-treatment interaction. When statistical differences were noted among groups in the dummy lead-in, the groups were compared using an analysis of covariance adjusting for baseline differences. Available data were analyzed up to the point of withdrawal for patients who did not complete the study protocol. The Fisher test for the protected least significant difference was used to make pair-wise comparisons. Results Patients A total of 188 patients entered the single-blind dummy lead-in period; 143 fulfilled the enrollment criteria and were randomly assigned to receive study drug or placebo (46 patients received 2.4 g/d, 49 patients received 1.6 g/d, and 48 patients received placebo). Two patients withdrew during the first week of the double-blind study1 for personal reasons and the other because of worsening asthma (both received 1.6 g/d of zileuton). Two patients were not included in the final analysis, because they were enrolled in a center that did not have representation in all three treatment groups (1 received 1.6 g/d of zileuton and 1 received placebo). The characteristics of the 139 evaluated patients are given in Table 1. Of the 139 patients who were still in the trial after 1 week, 12 evaluated patients left the study before completing the trial protocol (all their data were included up to the point of termination): 4 patients because of worsening asthma (1 received 2.4 g/d, 2 received 1.6 g/d, and 1 received placebo); 2 patients because of upper respiratory infections (1 received 2.4 g/d and 1 received placebo); 1 patient because of sinusitis (placebo); 1 patient because of urticaria (1.6 g/d); 3 patients because of personal reasons (1 in each group); and 1 patient because of headaches that had begun before randomization (2.4 g/d). Table 1. Characteristics or Evaluated Patients* Acute Effects on Airway Obstruction A single 600-mg dose of zileuton produced rapid bronchodilation (Figure 1). Compared with the mean FEV1 measured just before study drug ingestion (0 minutes), the mean FEV1 improved 30 minutes after a single 600-mg dose of zileuton and remained increased for the entire 2-hour observation period (P < 0.005 for all observation points). The maximum increase (14.6%) in the mean FEV1 was 0.35 L (CI, 0.25 to 0.45 L) (P < 0.001), which occurred at 60 minutes. No improvement of the FEV1 occurred in the placebo group (0.09 L [CI, 0.01 to 0.19 L]; P = 0.075). The improvement in the mean FEV1 after zileuton was greater than that after placebo at 60 and 120 minutes (P < 0.001 and P = 0.01, respectively). Figure 1. Change in the forced expiratory volume during the 2 hours after administration of zileuton or placebo. P P P Effects of 4 Weeks of Zileuton Administration on Airway Obstruction All three groups of patients had an initial impr
The Journal of Allergy and Clinical Immunology | 2013
Allen P. Kaplan; Dennis K. Ledford; Mark Ashby; Janice Canvin; James L. Zazzali; Edward R. Conner; Joachim Veith; Nikhil Kamath; Petra Staubach; Thilo Jakob; Robert G. Stirling; Piotr Kuna; William E. Berger; Marcus Maurer; Karin Rosén
BACKGROUND Patients with chronic idiopathic urticaria/chronic spontaneous urticaria (CIU/CSU) often continue to experience symptoms despite receiving standard-of-care therapy with H1-antihistamines along with 1 or more add-on therapies. OBJECTIVES We sought to evaluate the safety and efficacy of 24 weeks of treatment with omalizumab in patients with persistent CIU/CSU despite treatment with H₁-antihistamines at up to 4 times the approved dose plus H₂-antihistamines, leukotriene receptor antagonists, or both. METHODS In this phase III study patients were randomized to receive 6 subcutaneous injections at 4-week intervals of either 300 mg of omalizumab or placebo, followed by a 16-week observation period. The primary objective of the study was to evaluate the overall safety of omalizumab compared with placebo. Efficacy (itch severity, hive, and urticaria activity scores) was evaluated at weeks 12 and 24. RESULTS The overall incidence and severity of adverse events and serious adverse events were similar between omalizumab and placebo recipients; the safety profile was consistent with omalizumab in patients with allergic asthma. At week 12, the mean change from baseline in weekly itch severity score was -8.6 (95% CI, -9.3 to -7.8) in the omalizumab group compared with -4.0 (95% CI, -5.3 to -2.7) in the placebo group (P < .001). Significant improvements were seen for additional efficacy end points at week 12; these benefits were sustained to week 24. CONCLUSION Omalizumab was well tolerated and reduced the signs and symptoms of CIU/CSU in patients who remained symptomatic despite the use of H₁-antihistamines (up to 4 times the approved dose) plus H₂-antihistamines, leukotriene receptor antagonists, or both.
Allergy | 2009
G. Walter Canonica; Jean Bousquet; Thomas B. Casale; Richard F. Lockey; Carlos E. Baena-Cagnani; Ruby Pawankar; Paul C. Potter; Philippe Jean Bousquet; Linda Cox; Stephen R. Durham; Harold S. Nelson; Giovanni Passalacqua; Dermot Ryan; Jan Brozek; Enrico Compalati; Ronald Dahl; Luís Delgado; Roy Gerth van Wijk; Richard G. Gower; Dennis K. Ledford; Nelson Augusto Rosário Filho; Erkka Valovirta; O. M. Yusuf; Torsten Zuberbier; Wahiduzzaman Akhanda; Raúl Lázaro Castro Almarales; Ignacio J. Ansotegui; Floriano Bonifazi; Jan Ceuppens; Tomás Chivato
Co-Authors: Wahiduzzaman Akhanda, Raul Castro Almarales, Ignacio Ansotegui, Floriano Bonifazi, Jan Ceuppens, Tomás Chivato, Darina Dimova, Diana Dumitrascu, Luigi Fontana, Constance HKatelaris, Ranbir Kaulsay, Piotr Kuna, Dèsirée Larenas-Linnemann, Manolis Manoussakis, Kristof Nekam, Carlos Nunes, Robyn O’Hehir, José M Olaguibel, Nerin Bahceciler Onder, JungWon Park, Alfred Priftanji, Robert Puy, Luis Sarmiento, Glenis Scadding, Peter Schmid-Grendelmeier, Ester Seberova, Revaz Sepiashvili, Dirceu Solé, Alkis Togias, Carlo Tomino, Elina Toskala, Hugo Van Beever, Stefan Vieths*
Allergy | 2012
Nikolaos G. Papadopoulos; H. Arakawa; Adnan Custovic; James E. Gern; Robert F. Lemanske; Graham Roberts; Gary W.K. Wong; Heather J. Zar; Cezmi A. Akdis; Leonard B. Bacharier; Eugenio Baraldi; H. Van Bever; J. de Blic; A. L. Boner; Wesley Burks; Thomas B. Casale; J. A. Castro-Rodriguez; Yiqin Chen; Yehia M. El-Gamal; Mark L. Everard; Thomas Frischer; Mario Geller; J. Gereda; Daniel Yam Thiam Goh; Theresa W. Guilbert; Gunilla Hedlin; Peter W. Heymann; Soo-Jong Hong; E. M. Hossny; J. L. Huang
Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re‐evaluate and fine‐tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype‐specific treatment choices; however, this goal has not yet been achieved.
Current Opinion in Allergy and Clinical Immunology | 2012
F. Estelle R. Simons; Ledit Ardusso; M. Beatrice Bilò; Vesselin Dimov; Yehia M. El-Gamal; Dennis K. Ledford; Richard F. Lockey; Johannes Ring; Mario Sánchez-Borges; Gian Enrico Senna; Aziz Sheikh; Bernard Yu-Hor Thong; Margitta Worm
Purpose of reviewThe World Allergy Organization (WAO) Guidelines for the assessment and management of anaphylaxis published in early 2011 provide a global perspective on patient risk factors, triggers, clinical diagnosis, treatment, and prevention of anaphylaxis. In this 2012 Update, subsequently published, clinically relevant research in these areas is reviewed. Recent findingsPatient risk factors and co-factors that amplify anaphylaxis have been documented in prospective studies. The global perspective on the triggers of anaphylaxis has expanded. The clinical criteria for the diagnosis of anaphylaxis that are promulgated in the Guidelines have been validated. Some aspects of anaphylaxis treatment have been prospectively studied. Novel investigations of self-injectable epinephrine for treatment of anaphylaxis recurrences in the community have been performed. Progress has been made with regard to measurement of specific IgE to allergen components (component-resolved testing) that might help to distinguish clinical risk of future anaphylactic episodes to an allergen from asymptomatic sensitization to the allergen. New strategies for immune modulation to prevent food-induced anaphylaxis and new insights into subcutaneous immunotherapy to prevent venom-induced anaphylaxis have been described. SummaryResearch highlighted in this Update strengthens the evidence-based recommendations for assessment, management, and prevention of anaphylaxis made in the WAO Anaphylaxis Guidelines.
The Journal of Allergy and Clinical Immunology | 2011
Nicola A. Hanania; Monroe J. King; Sidney S. Braman; Carol A. Saltoun; Robert A. Wise; Paul L. Enright; Ann R. Falsey; Sameer K. Mathur; Joe W. Ramsdell; Linda Rogers; D. Stempel; John J. Lima; James E. Fish; Sandra R. Wilson; Cynthia M. Boyd; Kushang V. Patel; Charles G. Irvin; Barbara P. Yawn; Ethan A. Halm; Stephen I. Wasserman; Mark F. Sands; William B. Ershler; Dennis K. Ledford
Asthma in the elderly is underdiagnosed and undertreated, and there is a paucity of knowledge on the subject. The National Institute on Aging convened this workshop to identify what is known and what gaps in knowledge remain and suggest research directions needed to improve the understanding and care of asthma in the elderly. Asthma presenting at an advanced age often has similar clinical and physiologic consequences as seen with younger patients, but comorbid illnesses and the psychosocial effects of aging might affect the diagnosis, clinical presentation, and care of asthma in this population. At least 2 phenotypes exist among elderly patients with asthma; those with longstanding asthma have more severe airflow limitation and less complete reversibility than those with late-onset asthma. Many challenges exist in the recognition and treatment of asthma in the elderly. Furthermore, the pathophysiologic mechanisms of asthma in the elderly are likely to be different from those seen in young asthmatic patients, and these differences might influence the clinical course and outcomes of asthma in this population.