D. Lien
University of Alberta
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Featured researches published by D. Lien.
American Journal of Transplantation | 2005
Atul Humar; Deepali Kumar; Jutta K. Preiksaitis; Guy Boivin; Deborah Siegal; Jayne Fenton; Kathy Jackson; Sarah Nia; D. Lien
Cytomegalovirus (CMV) infection is common after lung transplantation. We performed a prospective trial of valganciclovir prophylaxis in lung recipients with outcomes compared to matched historical controls. The valganciclovir group (n = 40) (including D+/R– and R+ patients) was prospectively enrolled, and received oral valganciclovir 900 mg once daily for 12 weeks. Historical controls (n = 40) received 12 weeks of daily intravenous ganciclovir if D+/R– or 12 weeks of oral ganciclovir if R+. CMV viral load testing was done at two‐week intervals until 6 months posttransplant. Baseline demographics and immunosuppression were comparable in the two groups. The incidence of CMV viremia was 16/40 (40.0%) in the valganciclovir arm versus 18/40 (45%) in the ganciclovir arm (p = NS). The incidence of symptomatic CMV disease was 8/40 (20%) versus 7/40 (17.5%), respectively (p = NS). In both groups viremia, while on prophylaxis, was uncommon (valganciclovir: 0/40 and ganciclovir: 2/40). Peak viral load and time to viremia were similar in the two arms. High rates of viremia and symptomatic disease occurred in the D+/R– patients after discontinuation of prophylaxis. Genotypic CMV sequence analysis demonstrated low rates of ganciclovir resistance in both groups. Valganciclovir prophylaxis had similar efficacy to either intravenous ganciclovir (D+/R– patients), or oral ganciclovir (R+ patients) in lung recipients.
Journal of Heart and Lung Transplantation | 2011
Oriol Manuel; Atul Humar; Carine Berutto; Leticia Ely; Stefano Giulieri; D. Lien; Pascal Meylan; J. Weinkauf; Manuel Pascual; R. Nador; John-David Aubert; Deepali Kumar
BACKGROUND In this study we compared the immunogenicity of influenza vaccine administered intradermally to the standard intramuscular vaccination in lung transplant recipients. METHODS Patients were randomized to receive the trivalent inactivated seasonal 2008-9 influenza vaccine containing either 6 μg (intradermal) or 15 μg (intramuscular) of hemagglutinin per viral strain. Immunogenicity was assessed by measurement of geometric mean titer of antibodies using the hemagglutination-inhibition (HI) assay. Vaccine response was defined as a 4-fold or higher increase of antibody titers to at least one vaccine antigen. RESULTS Eighty-five patients received either the intradermal (n = 41) or intramuscular (n = 44) vaccine. Vaccine response was seen in 6 of 41 patients (14.6%) in the intradermal vs 8 of 43 (18.6%) in the intramuscular group (p = 0.77). Seroprotection (HI ≥ 1:32) was 39% for H1N1, 83% for H3N2 and 29% for B strain in the intradermal group vs 28% for H1N1, 98% for H3N2 and 58% for B strain in the intramuscular group (p = 0.36 for H1N1, p = 0.02 for H3N2, p < 0.01 for B). Mild adverse events were seen in 44% of patients in the intradermal group and 34% in the intramuscular group (p = 0.38). CONCLUSIONS Immunogenicity of the 2008-9 influenza vaccine given intradermally or intramuscularly was overall poor in lung transplant recipients. Novel strategies for influenza vaccination in this population are needed.
Journal of Heart and Lung Transplantation | 2006
Atul Humar; Karen Doucette; Deepali Kumar; Xiao-Li Pang; D. Lien; Kathy Jackson; Jutta K. Preiksaitis
Background Little is known about adenovirus infections in adult lung transplant recipients. Because the virus can establish latency, re-activation may be relatively common after transplantation. Methods We assessed adenovirus infection in 80 adult lung transplant recipients. Adenovirus polymerase chain reaction (real-time PCR assay; limit of detection ∼25 copies/ml plasma) was done on plasma samples collected at regular intervals until 1 year post-transplant. Results Adenovirus DNA was detected in 18 of 80 patients (22.5%) and in 19 of 595 (3.4%) plasma samples up to 12 months post-transplant. Median time to detection of viremia was 134 days post-transplant (range 1 to 370 days). Median viral load was 180 copies/ml plasma (range 50 to 360 copies/ml). Symptoms were evaluated at the time of adenovirus detection: 14 of 18 (78%) patients were asymptomatic; 4 of 18 (22%) patients had otherwise unexplained febrile/flu-like illness that resolved spontaneously. Adenovirus was not found to be a trigger for acute rejection. No detrimental effect on pulmonary function was seen immediately after adenovirus infection. Conclusions Adenovirus viremia is common in adult lung transplant recipients. In contrast to findings on adenoviral pneumonitis in lung transplant recipients, isolated episodes of low-level viremia are self-limited and do not trigger acute rejection or a decline in pulmonary function.
Transplantation | 2012
Adrian Egli; Jeff Fuller; Atul Humar; D. Lien; J. Weinkauf; R. Nador; A. Kapasi; Deepali Kumar
Background Universal antifungal prophylaxis with azoles is commonly used after lung transplantation. We noted an increase in isolates of Aspergillus calidoustus in our transplant population and hypothesized that increasing azole use (universal prophylaxis since 2008) may be promoting this infection. Methods Clinical and microbiologic data for A. calidoustus cases from 2008 to 2011 were extracted from chart review. For lung transplant patients, a case-control study was performed to determine risk factors, and incidence rates were calculated. Results From 2008 to 2011, we identified seven organ transplant recipients and one hematopoietic stem-cell transplant patient with positive A. calidoustus culture results in bronchoalveolar lavage at a median of 13 months after transplantation (interquartile range, 4–39 months). Chest computed tomographic scan was consistent with fungal infection in six of eight patients, and the European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria classified these as “probable” invasive aspergillosis. In the case-control study, there were no differences in immunosuppression, number of respiratory samples taken, length of intensive care unit stay, or rejection rates. Of controls, 33.3% received third-generation azole prophylaxis compared with 83.3% of cases (P=0.13). However, median duration of exposure was greater in cases than in controls (3 vs. 0 months, P=0.045). Fungal minimum inhibitory concentration for voriconazole was 4 µg/mL or greater for six of eight cases. Incidence rates in lung transplants showed an increase of A. calidoustus (0/1000 vs. 11.3/1000 patient-years in 2006–2007 and 2008–2011, respectively; P=0.018), whereas Aspergillus fumigatus cases decreased (73.9/1000 vs. 49.0/1000 patient-years, P=0.0066). Conclusions Pulmonary A. calidoustus seems to be an emerging pathogen mainly in lung transplants. We suggest that third-generation azole use reduced the incidence of A. fumigatus, but the incidence of A. calidoustus, an azole-resistant fungus, was increased.
Journal of Heart and Lung Transplantation | 2009
Oriol Manuel; D. Lien; J. Weinkauf; Atul Humar; Isabel Cobos; Deepali Kumar
BACKGROUND Data on the epidemiology of MRSA infection in lung transplantation is limited. METHODS We performed a 5-year retrospective study to assess the incidence and microbiologic and clinical characteristics of methicillin-resistant Staphylococcus aureus (MRSA) infection in a cohort of 163 lung transplant recipients. RESULTS Seventeen patients with MRSA colonization and/or infection were identified, for a calculated incidence rate of 76.1 cases per 1,000 transplanted-years. Pulsed-field gel electrophoresis identified 3 different distinct MRSA profiles, all of them consistent with hospital-associated MRSA infection. CONCLUSION Despite negative polymerase chain reaction (PCR) for the virulence factor Panton-Valentine leukocidin, MRSA infections resulted in significant disease and morbidity.
Nephrology Dialysis Transplantation | 2014
Pedro Fidalgo; Mohammed F. A. Ahmed; Steven R. Meyer; D. Lien; J. Weinkauf; Filipe S. Cardoso; Kathy Jackson; Sean M. Bagshaw
BACKGROUND Acute kidney injury (AKI) is a serious complication following lung transplantation (LTx). We aimed to describe the incidence and outcomes associated with AKI following LTx. METHODS A retrospective population-based cohort study of all adult recipients of LTx at the University of Alberta between 1990 and 2011. The primary outcome was AKI, defined and classified according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria, in the first 7 post-operative days. Secondary outcomes included risk factors, utilization of renal replacement therapy (RRT), occurrence of post-operative complications, mortality and kidney recovery. RESULTS Of 445 LTx recipients included, AKI occurred in 306 (68.8%), with severity classified as Stage I in 38.9% (n = 173), Stage II in 17.5% (n = 78) and Stage III in 12.4% (n = 55). RRT was received by 36 (8.1%). Factors associated with AKI included longer duration of cardiopulmonary bypass [per minute, odds ratio (OR) 1.003; 95% confidence interval (CI), 1.001-1.006; P = 0.02], and mechanical ventilation [per hour (log-transformed), OR 5.30; 95% CI, 3.04-9.24; P < 0.001], and use of cyclosporine (OR 2.03; 95% CI, 1.13-3.64; P = 0.02). In-hospital and 1-year mortality were significantly higher in those with AKI compared with no AKI (7.2 versus 0%; adjusted P = 0.001; 14.4 versus 5.0%; adjusted P = 0.02, respectively). At 3 months, those with AKI had greater sustained loss of kidney function compared with no AKI [estimated glomerular filtration rate, mean (SD): 68.9 (25.7) versus 75.3 (22.1) mL/min/1.73 m(2), P = 0.01]. CONCLUSIONS By the KDIGO definition, AKI occurred in two-thirds of patients following LTx. AKI portended greater risk of death and loss of kidney function.
American Journal of Transplantation | 2016
Karen Doucette; K. Halloran; A. Kapasi; D. Lien; J. Weinkauf
Hepatitis C virus (HCV) infection negatively impacts patient and graft survival following nonhepatic solid organ transplantation. Most data, however, are in kidney transplant, where despite modest impact on outcomes, transplantation is recommended for those with mild to moderate hepatic fibrosis given overall benefit compared to remaining on dialysis. In lung transplantation (LuTx), there is little data on outcomes and international guidelines are vague on the criteria under which transplant should be considered. The University of Alberta Lung Transplant Program routinely considers patients with HCV for lung transplant based on criteria extrapolated from the kidney transplant literature. Here we describe the outcomes of 27 HCV‐positive, compared to 443 HCV‐negative LuTx recipients. Prior to transplant, five patients were treated for HCV and cured. At the time of transplant, 14 patients remained HCV RNA positive. The 1‐, 3‐, and 5‐year survival were similar in HCV RNA–positive versus ‐negative recipients at 93%, 77%, and 77% versus 86%, 75%, and 66% (p = 0.93), respectively. Long‐term follow‐up in eight patients demonstrated no significant progression of fibrosis. In our cohort, HCV did not impact LuTx outcomes and in the era of interferon‐free HCV therapies this should not be a barrier to LuTx.
Patient Related Outcome Measures | 2010
Maria J Santana; David Feeny; J. Weinkauf; R. Nador; A. Kapasi; K. Jackson; Marianne Schafenacker; Dalyce Zuk; D. Lien
Objective: To assess the use of patient-reported outcome (PROs) measures in the routine clinical care of lung–heart transplant patients. We assessed whether the addition of PROs in routine clinical care affected the duration of the consultation and patient’s and clinician’s views. Method: Consecutive lung–heart transplant patients visiting the outpatient clinic, University of Alberta Hospital, completed the Chronic Respiratory Questionnaire (CRQ) and the Health Utilities Index (HUI) on touchscreen computers. Information on the patient’s responses was made available to the members of the transplant team prior to the encounter with the patient. The duration of clinical encounters was noted. At the end of every visit, clinicians completed a questionnaire on the usefulness of having PRO information available. After 6 months patients completed a survey of their experiences. Results: The final patient sample consisted of 172 patients with a mean (SD) age of 52 (13.3) years old; 47% were female; 68% were organ recipients and 32% candidates. The transplant team, comprising four pulmunologists, two nurses, and one pharmacist had an average of 9 years of practical experience in pulmunology. The mean duration of patient–clinician encounters in minutes was 15.15 (4.52). Ninety-eight percent of patients indicated that they would be happy to complete the CRQ and HUI at every clinic visit. Ninety-one percent of the assessments completed by clinicians showed complete satisfaction with the use of PROs in routine practice. Further, the clinicians developed guidelines for the use of PRO information in clinical practice. Conclusions: The incorporation of PRO measures in the routine clinical care of lung–heart transplant patients resulted in a reduction of the duration of patient–clinician encounters. The experience was well accepted by patients and clinicians. We conclude that the routine use of PROs in lung–heart transplant patients has become standard practice.
Journal of Critical Care | 2014
Pedro Fidalgo; Mohammed F. A. Ahmed; Steven R. Meyer; D. Lien; J. Weinkauf; A. Kapasi; Filipe S. Cardoso; Kathy Jackson; Sean M. Bagshaw
PURPOSE Acute kidney injury (AKI) is a common occurrence after lung transplantation (LTx). Whether transient AKI or early recovery is associated with improved outcome is uncertain. Our aim was to describe the incidence, factors, and outcomes associated with transient AKI after LTx. MATERIALS AND METHODS We performed a retrospective cohort study of all adult recipients of LTx at the University of Alberta between 1990 and 2011. Our primary outcome transient AKI was defined as return of serum creatinine below Kidney Disease-Improving Global Outcome AKI stage I within 7days after LTx. Secondary outcomes included occurrence of postoperative complications, mortality, and long-term kidney function. RESULTS Of 445 LTx patients enrolled, AKI occurred in 306 (68.8%) within the first week after LTx. Of these, transient AKI (or early recovery) occurred in 157 (51.3%). Transient AKI was associated with fewer complications including tracheostomy (17.2% vs 38.3%; P<.001), reintubation (16.4% vs 41.9%; P<.001), decreased duration of mechanical ventilation (median [interquartile range], 69 [41-142] vs 189 [63-403] hours; P<.001), and lower rates of chronic kidney disease at 3 months (28.5% vs 51.1%, P<.001) and 1 year (49.6% vs 66.7%, P=.01) compared with persistent AKI. Factors independently associated with persistent AKI were higher body mass index (per unit; odds ratio [OR], 0.91; 95% confidence interval, 0.85-0.98; P=.01), cyclosporine use (OR, 0.29; 0.12-0.67; P=.01), longer duration of mechanical ventilation (per hour [log transformed]; OR, 0.42; 0.21-0.81; P=.01), and AKI stages II to III (OR, 0.16; 0.08-0.29; P<.001). Persistent AKI was associated with higher adjusted hazard of death (hazard ratio, 1.77 [1.08-2.93]; P=.02) when compared with transient AKI (1.44 [0.93-2.19], P=.09) and no AKI (reference category), respectively. CONCLUSIONS Transient AKI after LTx is associated with fewer complications and improved survival. Among survivors, persistent AKI portends an increased risk for long-term chronic kidney disease.
American Journal of Transplantation | 2015
J. Y. W. Wong; Holger Buchholz; Lindsay M. Ryerson; Alf Conradi; Ian Adatia; John D. Dyck; Ivan M. Rebeyka; D. Lien; John T. Mullen
Lung transplantation (LTx) may be denied for children on extracorporeal membrane oxygenation (ECMO) due to high risk of cerebral hemorrhage. Rarely has successful LTx been reported in children over 10 years of age receiving awake or ambulatory veno‐venous ECMO. LTx following support with ambulatory veno‐arterial ECMO (VA ECMO) in children has never been reported to our knowledge. We present the case of a 4‐year‐old, 12‐kg child with heritable pulmonary artery hypertension and refractory right ventricular failure. She was successfully bridged to heart–lung transplantation (HLTx) using ambulatory VA ECMO. Initial resuscitation with standard VA ECMO was converted to an ambulatory circuit using Berlin heart cannulae. She was extubated and ambulating around her bed while on VA ECMO for 40 days. She received an HLTx from an oversized marginal lung donor. Despite a cardiac arrest and Grade 3 primary graft dysfunction, she made a full recovery without neurological deficits. She achieved 104% force expiratory volume in 1 s 33 months post‐HLTx. Ambulatory VA ECMO may be a useful strategy to bridge very young children to LTx or HLTx. Patient tailored ECMO cannulation, minimization of hemorrhage, and thrombosis risks while on ECMO contributed to a successful HLTx in our patient.