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Featured researches published by Doug Helmersen.


Lancet Infectious Diseases | 2010

Outcomes from pandemic influenza A H1N1 infection in recipients of solid-organ transplants: a multicentre cohort study

Deepali Kumar; Marian G. Michaels; Michele I. Morris; Michael Green; Robin K. Avery; Catherine Liu; Lara Danziger-Isakov; Valentina Stosor; Michele M. Estabrook; Soren Gantt; Kieren A. Marr; Stanley I. Martin; Fernanda P. Silveira; Raymund R. Razonable; Upton Allen; Marilyn E. Levi; G. Marshall Lyon; Lorraine Bell; Shirish Huprikar; Gopi Patel; Kevin Gregg; Kenneth Pursell; Doug Helmersen; Kathleen G. Julian; Kevin T. Shiley; Bartholomew Bono; Vikas R. Dharnidharka; Gelareh Alavi; Jayant S Kalpoe; Shmuel Shoham

BACKGROUND There are few data on the epidemiology and outcomes of influenza infection in recipients of solid-organ transplants. We aimed to establish the outcomes of pandemic influenza A H1N1 and factors leading to severe disease in a cohort of patients who had received transplants. METHODS We did a multicentre cohort study of adults and children who had received organ transplants with microbiological confirmation of influenza A infection from April to December, 2009. Centres were identified through the American Society of Transplantation Influenza Collaborative Study Group. Demographics, clinical presentation, treatment, and outcomes were assessed. Severity of disease was measured by admission to hospital and intensive care units (ICUs). The data were analysed with descriptive statistics. Proportions were compared by use of chi(2) tests. We used univariate analysis to identify factors leading to pneumonia, admission to hospital, and admission to an ICU. Multivariate analysis was done by use of a stepwise logistic regression model. We analysed deaths with Kaplan-Meier survival analysis. FINDINGS We assessed 237 cases of medically attended influenza A H1N1 reported from 26 transplant centres during the study period. Transplant types included kidney, liver, heart, lung, and others. Both adults (154 patients; median age 47 years) and children (83; 9 years) were assessed. Median time from transplant was 3.6 years. 167 (71%) of 237 patients were admitted to hospital. Data on complications were available for 230 patients; 73 (32%) had pneumonia, 37 (16%) were admitted to ICUs, and ten (4%) died. Antiviral treatment was used in 223 (94%) patients (primarily oseltamivir monotherapy). Seven (8%) patients given antiviral drugs within 48 h of symptom onset were admitted to an ICU compared with 28 (22.4%) given antivirals later (p=0.007). Children who received transplants were less likely to present with pneumonia than adults, but rates of admission to hospital and ICU were similar. INTERPRETATION Influenza A H1N1 caused substantial morbidity in recipients of solid-organ transplants during the 2009-10 pandemic. Starting antiviral therapy early is associated with clinical benefit as measured by need for ICU admission and mechanical ventilation. FUNDING None.


Journal of Cystic Fibrosis | 2016

Epidemic Pseudomonas aeruginosa infection in patients with cystic fibrosis is not a risk factor for poor clinical Outcomes following lung transplantation

Julia Pritchard; Mitesh V. Thakrar; Ranjani Somayaji; Michael G. Surette; Harvey R. Rabin; Doug Helmersen; Dale Lien; Swathi Purighalla; Barbara Waddell; Michael D. Parkins

BACKGROUND Epidemic strains of Pseudomonas aeruginosa (ePA) causing infection in cystic fibrosis (CF) have been commonly identified from clinics around the world. ePA disproportionally impacts CF patient pre-transplant outcomes manifesting in increased exacerbation frequency, worsened treatment burden and increased rate of lung function decline, and disproportionally leads to death and/or transplantation. As other CF factors such as pre-transplant infection with multi-resistant organisms, and isolation of P. aeruginosa in the post transplant graft, may impact post-transplant outcomes, we sought to determine if infection with ePA similarly adversely impact post-transplant outcomes. METHODS Between 1991-2014, 53 CF patients from our center received lung transplants. Bacterial strain typing was performed retrospectively on isolates collected prior to transplantation. Comprehensive chart reviews were performed to obtain baseline patient characteristics and post-transplant outcomes. RESULTS Of the 53 transplanted patients, 57% of patients were infected with ePA prior to transplant; the other 43% of patients had unique strains of P. aeruginosa. Mean age at transplant was 29.0years for ePA and 33.3years for unique (p=0.04). There were no differences in overall survival (HR=0.75, 95% CI 0.31-1.79), bronchiolitis obliterans syndrome (BOS) free survival (HR 1.43, 95% CI 0.54-4.84) or all other assessed outcomes including exacerbation frequency, chronic renal failure, acute cellular rejections, Aspergillus infection, airway stenosis, and post-transplant lymphoproliferative disorder. CONCLUSION Unlike pre-transplant outcomes, CF patients infected with ePA do not experience worse post-transplant outcomes than those infected with unique strains. Therefore, lung transplantation should be considered for all patients with P. aeruginosa infection and end stage lung disease, irrespective of infection with ePA.


Canadian Respiratory Journal | 2003

Sildenafil Treatment of Primary Pulmonary Hypertension

Kevin B. Laupland; Doug Helmersen; David A. Zygun; Sidney M Viner

A 37-year-old woman with primary pulmonary hypertension and worsening symptomatology underwent pulmonary artery (PA) catheterization and vasodilator trials. Oxygen had no effect, but 10 parts/million of nitric oxide reduced mean PA (PAm) pressure by 20%. Prostacyclin infusion at 8 ng/kg/min decreased the PAm pressure by 11%, but further dose increases were limited by systemic hypotension. Sildenafil in doses of 25 mg or higher resulted in an average decrease of 14% in PAm pressure. Sildenafil is a potentially useful treatment option for patients with primary pulmonary hypertension, and further investigation is warranted.


Respiratory medicine case reports | 2016

Pulmonary arterial hypertension secondary to adult-onset Still's disease: Response to cyclosporine and sildenafil over 15 years of follow-up.

Jason Weatherald; Johan Lategan; Doug Helmersen

Adult onset Still’s disease (AOSD) is an autoimmune disease characterized by systemic inflammation and is a rarely reported cause of pulmonary arterial hypertension (PAH). We describe the clinical course of a 40-year-old woman who presented with PAH 19 months after a diagnosis of AOSD. Sildenafil and immunosuppressive therapy with cyclosporine resulted in clinical and hemodynamic improvement with long-term survival 15 years after her initial presentation of AOSD. We review the literature for published cases of PAH due to AOSD and discuss the potential mechanisms relating inflammatory diseases and PAH.


Canadian Journal of Respiratory, Critical Care, and Sleep Medicine | 2018

Complications of pulmonary artery aneurysms in pulmonary arterial hypertension

Luke Rannelli; Jeffrey Shaw; Rhea Varughese; Mitesh V. Thakrar; Naushad Hirani; Gail Nicholson; Doug Helmersen; Jason Weatherald

ABSTRACT Pulmonary artery aneurysm (PAA) is a rare complication of pulmonary arterial hypertension (PAH), often occurring in patients with long-standing disease. Complications of PAA include pulmonary artery rupture, thrombosis, pulmonic valve regurgitation and coronary artery compression, which can result in myocardial ischemia. Diagnosis of coronary artery compression due to PAA is based on suggestive symptoms, imaging and coronary angiography. We present a case of a 70-year-old Caucasian female with longstanding vaso-reactive PAH complicated by a large PAA compressing the left anterior descending (LAD) coronary artery. The compressed LAD was not amenable to coronary stenting, however due to extensive coronary collateralization she was managed medically with dual antiplatelet therapy and cardiovascular risk reduction, with improvement in symptoms and stability for over 2 years.


Canadian Respiratory Journal | 2010

Diagnostic evaluation and management of chronic thromboembolic pulmonary hypertension: A clinical practice guideline

Sanjay Mehta; Doug Helmersen; Steeve Provencher; Naushad Hirani; Fraser D. Rubens; Marc de Perrot; Mark D. Blostein; Kim Boutet; Frcpc; George Chandy; Carole Dennie; John Granton; Paul Hernandez; Andrew Hirsch; Karen Laframboise; Robert D. Levy; D. Lien; Simon Martel; Gerard Shoemaker; John R. Swiston; Justin Weinkauf; Sir Mortimer; Davis Jewish; Nova Scotia; British Columbia


Chest | 2004

Lymphangioleiomyomatosis (LAM) Presenting as Severe Pulmonary Hypertension

Paul MacEachern; Sid Viner; Francis H. Y. Green; Doug Helmersen


Journal of Heart and Lung Transplantation | 2018

Initial Combination Therapy With Riociguat and Ambrisentan in Pulmonary Arterial Hypertension: A Prospective Open-label Study

Mitesh V. Thakrar; Jason Weatherald; R.A. Varughese; Doug Helmersen; C. Lydell; N. Fine; Naushad Hirani


Journal of Heart and Lung Transplantation | 2016

A Multi-Centre Study on the Effects of Iyengar Yoga on Health Related Quality of Life in Patients with Pulmonary Arterial Hypertension

Mitesh V. Thakrar; Doug Helmersen; Naushad Hirani; K. Jackson; D. Lien; M.J. Santana


European Respiratory Journal | 2016

Diagnostic utility of the physical examination for pulmonary hypertension

Kevin J. Solverson; Daniel Vis; Micheal Braganza; Jeff Shaw; Luke Rannelli; Mitesh V. Thakrar; Rhea Varughese; Naushad Hirani; Doug Helmersen; Jason Weatherald

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D. Lien

University of Alberta

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