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Dive into the research topics where Helen Leather is active.

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Featured researches published by Helen Leather.


Blood | 2010

Randomized, double-blind trial of fluconazole versus voriconazole for prevention of invasive fungal infection after allogeneic hematopoietic cell transplantation

John R. Wingard; Shelly L. Carter; Thomas J. Walsh; Joanne Kurtzberg; Trudy N. Small; Lindsey R. Baden; Iris Gersten; Adam Mendizabal; Helen Leather; Dennis L. Confer; Richard T. Maziarz; Edward A. Stadtmauer; Javier Bolaños-Meade; Janice M. Brown; John F. DiPersio; Michael Boeckh; Kieren A. Marr

Invasive fungal infection (IFI) is a serious threat after allogeneic hematopoietic cell transplant (HCT). This multicenter, randomized, double-blind trial compared fluconazole (N = 295) versus voriconazole (N = 305) for the prevention of IFI in the context of a structured fungal screening program. Patients undergoing myeloablative allogeneic HCT were randomized before HCT to receive study drugs for 100 days, or for 180 days in higher-risk patients. Serum galactomannan was assayed twice weekly for 60 days, then at least weekly until day 100. Positive galactomannan or suggestive signs triggered mandatory evaluation for IFI. The primary endpoint was freedom from IFI or death (fungal-free survival; FFS) at 180 days. Despite trends to fewer IFIs (7.3% vs 11.2%; P = .12), Aspergillus infections (9 vs 17; P = .09), and less frequent empiric antifungal therapy (24.1% vs 30.2%, P = .11) with voriconazole, FFS rates (75% vs 78%; P = .49) at 180 days were similar with fluconazole and voriconazole, respectively. Relapse-free and overall survival and the incidence of severe adverse events were also similar. This study demonstrates that in the context of intensive monitoring and structured empiric antifungal therapy, 6-month FFS and overall survival did not differ in allogeneic HCT recipients given prophylactic fluconazole or voriconazole. This trial was registered at www.clinicaltrials.gov as NCT00075803.


Clinical Infectious Diseases | 2001

Evolution, Incidence, and Susceptibility of Bacterial Bloodstream Isolates from 519 Bone Marrow Transplant Patients

Berjan A. Collin; Helen Leather; John R. Wingard; Reuben Ramphal

Bacteria remain an important cause of infection in bone marrow transplants. To examine shifts in the etiology and susceptibility of bacterial isolates from transplants, we reviewed the incidence and susceptibility of blood isolates during a 7-year period. The infection rate fell dramatically during this time. Gram-positive organisms were isolated more often than gram-negative organisms, but the trend is reversing. Streptococci surpassed staphylococci for 5 years as the leading pathogen. Increasing resistance to penicillin, ciprofloxacin, and imipenem was noted in Streptococcus species. With the exception of type 1 beta-lactamase-producing bacteria and Pseudomonas aeruginosa, gram-negative isolates remained overall susceptible to ceftazidime. Increased antibiotic prophylaxis coincided with the reduction in percentage of infected patients and increase in resistance to beta-lactam antibiotics. Mortality attributed to bacteremia was low except for infections caused by P. aeruginosa and the Enterobacter, Serratia, Citrobacter group. There was no mortality attributable to gram-positive organisms such as Staphylococcus aureus and viridans streptococci.


Bone Marrow Transplantation | 2002

Late onset of invasive aspergillus infection in bone marrow transplant patients at a university hospital

Wb Grow; Jan S. Moreb; D Roque; K Manion; Helen Leather; Vijay Reddy; S.A. Khan; Kj Finiewicz; H Nguyen; Cj Clancy; Paulette Mehta; John R. Wingard

Despite new antifungal treatment strategies, invasive aspergillosis (IA) remains a principal cause of infectious mortality after bone marrow transplantation (BMT). We reviewed the medical records of 93 allogeneic and 149 autologous transplant recipients during a 20 month period, with attention to cases of proven or probable IA. No autologous transplant recipient developed IA, whereas IA was seen in 15.1% of allogeneic recipients (including two of five patients with a prior history of IA despite prophylaxis), for an overall incidence of 5.8%. The median time to occurrence was 92 days post transplant, with no de novo cases developing prior to engraftment. Survival 100 days from diagnosis was 29%. Risk factors for the development of IA included ⩾21 days of corticosteroid therapy of ⩾1 mg/kg/day and post-transplant cytomegalovirus (CMV) infection. These two risk factors were statistically linked. Our data illustrate a shift toward a later occurrence of post-transplant IA, suggesting a need for close, prolonged surveillance in the outpatient environment. The contributory role of protracted corticosteroid use is also highlighted. These data have important implications in an era of alternate donor transplants and more intense immunosuppression. Established strategies implementing newer, less toxic antifungal agents as prophylaxis in high-risk patients are needed.Bone Marrow Transplantation (2002) 29, 15–19. doi:10.1038/sj.bmt.1703332


Journal of Clinical Microbiology | 2007

Bronchoalveolar lavage galactomannan in diagnosis of invasive pulmonary aspergillosis among solid-organ transplant recipients.

Cornelius J. Clancy; Reia A. Jaber; Helen Leather; John R. Wingard; Benjamin Staley; L. Joseph Wheat; Christina Cline; Kenneth H. Rand; Denise Schain; Maher A. Baz; M. Hong Nguyen

ABSTRACT We review the experience at our institution with galactomannan (GM) testing of bronchoalveolar lavage (BAL) fluid in the diagnosis of invasive pulmonary aspergillosis (IPA) among solid-organ transplant recipients. Among 81 patients for whom BAL GM testing was ordered (heart, 24; kidney, 22; liver, 19; lung, 16), there were five cases of proven or probable IPA. All five patients had BAL GM of ≥2.1 and survived following antifungal therapy. The sensitivity, specificity, and positive and negative predictive values for BAL GM testing at a cutoff of ≥1.0 were 100%, 90.8%, 41.7%, and 100%, respectively. The sensitivity of BAL GM testing was better than that of conventional tests such as serum GM or BAL cytology and culture. Moreover, a positive BAL GM test diagnosed IPA several days to 4 weeks before other methods for three patients. Twelve patients had BAL GM of ≥0.5 but no evidence of IPA. Among these, lung transplant recipients accounted for 41.7% (5/12) of the false-positive results, reflecting frequent colonization of airways in this population. Excluding lung transplants, the specificity and positive predictive value for other solid-organ transplants increased to 92.9% and 62.5%, respectively (cutoff, ≥1.0). In conclusion, BAL GM testing facilitated more-rapid diagnoses of IPA and the institution of antifungal therapy among non-lung solid-organ transplant recipients and helped to rule out IPA.


Biology of Blood and Marrow Transplantation | 2014

Optimizing Autologous Stem Cell Mobilization Strategies to Improve Patient Outcomes: Consensus Guidelines and Recommendations

Sergio Giralt; Luciano J. Costa; Jeffrey Schriber; John F. DiPersio; Richard T. Maziarz; John M. McCarty; Paul J. Shaughnessy; Edward L. Snyder; William Bensinger; Edward A. Copelan; Chitra Hosing; Robert S. Negrin; Finn Bo Petersen; Damiano Rondelli; Robert J. Soiffer; Helen Leather; Amy Pazzalia; Steven M. Devine

Autologous hematopoietic stem cell transplantation (aHSCT) is a well-established treatment for malignancies such as multiple myeloma (MM) and lymphomas. Various changes in the field over the past decade, including the frequent use of tandem aHSCT in MM, the advent of novel therapies for the treatment of MM and lymphoma, and the addition of new stem cell mobilization techniques, have led to the need to reassess current stem cell mobilization strategies. Mobilization failures with traditional strategies are common and result in delays in treatment and increased cost and resource utilization. Recently, plerixafor-containing strategies have been shown to significantly reduce mobilization failure rates, but the ideal method to maximize stem cell yields and minimize costs associated with collection has not yet been determined. A panel of experts convened to discuss the currently available data on autologous hematopoietic stem cell mobilization and transplantation and to devise guidelines to optimize mobilization strategies. Herein is a summary of their discussion and consensus.


Clinical and Vaccine Immunology | 2008

Performance Characteristics of the Platelia Aspergillus Enzyme Immunoassay for Detection of Aspergillus Galactomannan Antigen in Bronchoalveolar Lavage Fluid

Shahid Husain; Cornelius J. Clancy; M.H. Nguyen; S. Swartzentruber; Helen Leather; A. M. LeMonte; Michelle Durkin; Kenneth S. Knox; Chadi A. Hage; C. Bentsen; Nina Singh; John R. Wingard; Lawrence J. Wheat

ABSTRACT We have evaluated the Platelia Aspergillus enzyme immunoassay for detection of galactomannan in bronchoalveolar lavage (BAL) specimens in solid organ transplant patients with aspergillosis. The precision and reproducibility in serum or BAL to which galactomannan was added were similar. Sensitivity was 81.8% in patients with aspergillosis, and specificity was 95.8% in lung transplant patients who underwent BAL for surveillance for infection or rejection. Among transplant controls, positive results were more common in patients (i) who underwent diagnostic BAL performed for evaluation of symptoms or chest computed tomographic abnormalities, (ii) who had undergone lung transplantation, or (iii) who were colonized with Aspergillus. Galactomannan testing in BAL is useful for diagnosis of aspergillosis in transplant patients. The significance of positive results in patients without confirmed aspergillosis requires further evaluation.


Journal of Clinical Microbiology | 2007

Use of Bronchoalveolar Lavage To Detect Galactomannan for Diagnosis of Pulmonary Aspergillosis among Nonimmunocompromised Hosts

M. Hong Nguyen; Reia A. Jaber; Helen Leather; John R. Wingard; Benjamin Staley; L. Joseph Wheat; Christina Cline; Maher A. Baz; Kenneth H. Rand; Cornelius J. Clancy

ABSTRACT Pulmonary aspergillosis in nonimmunocompromised hosts, although rare, is being increasingly recognized. The diagnosis of pulmonary aspergillosis is difficult, since the recovery of Aspergillus from respiratory samples cannot differentiate colonization from invasion. We assessed the role of bronchoalveolar lavage (BAL) in detecting galactomannan (GM) for diagnosing pulmonary aspergillosis in 73 nonimmunocompromised patients with pulmonary infiltrates for whom the test was ordered. Six patients had pulmonary aspergillosis, two each with acute invasive pulmonary aspergillosis, chronic necrotizing pulmonary aspergillosis, and aspergilloma. All six patients had a BAL GM level of ≥1.18. The sensitivity, specificity, and negative predictive value (NPV) for a BAL GM level of ≥1.0 were 100%, 88.1%, and 100%, respectively. Notably, the positive predictive value (PPV) was only 42.9%, likely reflecting the low prevalence of pulmonary aspergillosis among nonimmunosuppressed patients. The combination of BAL microscopy and culture had a sensitivity and NPV similar to those of BAL GM detection but a higher specificity and PPV (92.5% and 54.6%, respectively). Moreover, a BAL GM test did not identify any cases that were not diagnosed by conventional methods like microscopy and culture. In conclusion, there was no conclusive benefit of determining BAL GM levels in the diagnosis of pulmonary aspergillosis among nonimmunocompromised hosts. Given the likelihood of false-positive results, a BAL GM test should not be ordered routinely in this population.


Journal of the National Cancer Institute | 2010

Adequacy of Published Oncology Randomized Controlled Trials to Provide Therapeutic Details Needed for Clinical Application

Jennifer M. Duff; Helen Leather; Edmund O. Walden; Kourtney D. LaPlant; Thomas J. George

BACKGROUND Randomized controlled trials (RCTs) improve clinical care through evidence-based results. Guidelines exist for RCT result reporting, but specific details of therapeutic administration promote clinical application and reproduction of the trial design. We assess the reporting methodology in RCTs published in major oncology journals. METHODS Ten essential elements of RCT reporting were identified and included drug name, dose, route, cycle length, maximum number of cycles, premedication, growth factor support, patient monitoring parameters, and dosing adjustments for hematologic and organ-specific toxicity. All therapy-based oncology RCTs published between 2005 and 2008 in the New England Journal of Medicine (NEJM), Journal of Clinical Oncology (JCO), Journal of the National Cancer Institute (JNCI), Blood, and Cancer were analyzed for inclusion of these 10 elements. RESULTS Of 339 identified articles, 262 were included in the final analysis (165 from JCO, 31 from NEJM, 27 from Cancer, 20 from JNCI, and 19 from Blood). Premedication, growth factor support, and dose adjustments for toxicities were each reported less than half of the time. Only 30 articles (11%) met the main objective of complete data reporting (ie, all 10 essential elements) and was highest in JNCI (5/20; 25%), followed by Cancer (5/27; 18%), JCO (18/165; 11%), Blood (1/19; 5%), and NEJM (1/31; 3%). The presence of an online appendix did not substantially improve complete reporting. CONCLUSIONS RCTs published in major oncology journals do not consistently report essential therapeutic details necessary for translation of the trial findings to clinical practice. Potential solutions to improve reporting include modification of submission guidelines, use of online appendices, and providing open access to trial protocols.


Biology of Blood and Marrow Transplantation | 2014

Peripheral Blood Progenitor Cell Mobilization for Autologous and Allogeneic Hematopoietic Cell Transplantation: Guidelines from the American Society for Blood and Marrow Transplantation

Hien K. Duong; Bipin N. Savani; Ed Copelan; Steven M. Devine; Luciano J. Costa; John R. Wingard; Paul J. Shaughnessy; Navneet S. Majhail; Miguel Angel Perales; Corey Cutler; William Bensinger; Mark R. Litzow; Mohamad Mohty; Richard E. Champlin; Helen Leather; Sergio Giralt; Paul A. Carpenter

Peripheral blood progenitor cell mobilization practices vary significantly among institutions. Effective mobilization regimens include growth factor alone, chemotherapy and growth factor combined, and, more recently, incorporation of plerixafor with either approach. Many institutions have developed algorithms to improve stem cell mobilization success rates and cost-effectiveness. However, an optimal stem cell mobilization regimen has not been defined. Practical guidelines are needed to address important clinical questions, including which growth factor is optimal, what chemotherapy and dose is most effective, and when to initiate leukapheresis. We present recommendations, based on a comprehensive review of the literature, from the American Society of Blood and Marrow Transplantation.


Infectious Disease Clinics of North America | 2001

Infections following hematopoietic stem cell transplantation.

Helen Leather; John R. Wingard

Numerous advances have been made in the management of infection in HSCT recipients. With increasing knowledge the authors are able to prevent several serious infections from occurring, and reduce the severity of infections once they occur. Despite these advances, several previously unrecognized pathogens have emerged and pose risks to this population. Ongoing surveillance and reporting of atypical infections are warranted. Transplant and infectious disease clinicians alike must be vigilant to the shifts in infectious syndromes as a consequence of various prophylaxis and preemptive strategies, and be ready to modify empiric strategies to meet the changing microbiologic milieu. As we increase our understanding of the HSCT process, and use the immune system rather than relying on high-dose chemotherapy, the authors are likely to reduce toxicities and improve patient outcomes.

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