Andres Pelaez

Efficacy of Oral Ribavirin in Lung Transplant Patients With Respiratory Syncytial Virus Lower Respiratory Tract Infection

BACKGROUND Respiratory syncytial virus (RSV) can cause severe lower respiratory tract infection (LRI) and is a risk factor for the development of bronchiolitis obliterans syndrome (BOS) after lung transplantation (LTx). Currently, the most widely used therapy for RSV is inhaled ribavirin. However, this therapy is costly and cumbersome. We investigated the utility of using oral ribavirin for the treatment of RSV infection after LTx. METHODS RSV was identified in nasopharyngeal swabs (NPS) or bronchoalveolar lavage (BAL) using direct fluorescent antibody (DFA) in 5 symptomatic LTx patients diagnosed with LRI. Data were collected from December 2005 and August 2007 and included: age; gender; type of LTx; underlying disease; date of RSV; pulmonary function prior to, during and up to 565 days post-RSV infection; need for mechanical ventilation; concurrent infections; and radiographic features. Patients received oral ribavirin for 10 days with solumedrol (10 to 15 mg/kg/day intravenously) for 3 days, until repeat NPS were negative. RESULTS Five patients had their RSV-LRI diagnosis made at a median of 300 days post-LTx. Mean forced expiratory volume in 1 second (FEV(1)) fell 21% (p < 0.012) during infection. After treatment, FEV(1) returned to baseline and was maintained at follow-up of 565 days. There were no complications and no deaths with oral therapy. A 10-day course of oral ribavirin cost

Bilateral Lung Transplantation Offers Better Long-Term Survival, Compared With Single-Lung Transplantation, for Younger Patients With Idiopathic Pulmonary Fibrosis

700 compared with

Receptor for Advanced Glycation End Products in Donor Lungs Is Associated with Primary Graft Dysfunction After Lung Transplantation

14,000 for nebulized ribavirin at 6 g/day. CONCLUSIONS Treatment of RSV after LTx with oral ribavirin and corticosteroids is well tolerated, effective and less costly than inhaled ribavirin. Further studies are needed to directly compare the long-term efficacy of oral vs nebulized therapy for RSV.

Gastroesophageal Reflux Disease Is Associated With an Increased Rate of Acute Rejection in Lung Transplant Allografts

BACKGROUND Single-lung transplantation (SLT) and bilateral lung transplantation (BLT) are both good options for patients with end-stage lung disease secondary to idiopathic pulmonary fibrosis. It is, however, unclear whether BLT offers any survival advantage over SLT. The purpose of our study was to evaluate a large group of patients to determine if either SLT or BLT officered a long-term survival advantage for patients with IPF. METHODS This was an Institutional Review Board-approved retrospective analysis of the United Network of Organ Sharing database from 1987 to 2008. Survival was determined using Kaplan-Meir estimates and the effect of laterality was determined by Cox proportional hazards and propensity analyses. RESULTS Lung transplantation for idiopathic pulmonary fibrosis was performed in 3,860 patients (2,431 SLTs and 1429 BLTs). Multivariate and propensity analysis failed to show any survival advantage for BLT (hazard ratio = 0.90, 95% confidence interval = 0.78 to 1.0, p = 0.11). One-year conditional survival favored BLT (hazard ratio 0.73, 95% confidence interval 0.60 to 0.87, p = 0.00064). Risk factors for early death included recipient age over 57 and donor age over 36 years. CONCLUSIONS Bilateral lung transplantation should be considered for younger patients with idiopathic pulmonary fibrosis and results may be optimized when younger donors are used.

Dynamics of Human Regulatory T Cells in Lung Lavages of Lung Transplant Recipients

Development of primary graft dysfunction (PGD) is associated with poor outcomes after transplantation. We hypothesized that Receptor for Advanced Glycation End‐products (RAGE) levels in donor lungs is associated with the development of PGD. Furthermore, we hypothesized that RAGE levels would be increased with PGD in recipients after transplantation. We measured RAGE in bronchoalveolar lavage fluid (BALf) from 25 donors and 34 recipients. RAGE was also detected in biopsies (transbronchial biopsy) from recipients with and without PGD. RAGE levels were significantly higher in donor lungs that subsequently developed sustained PGD versus transplanted lungs that did not display PGD. Donor RAGE level was a predictor of recipient PGD (odds ratio = 1.768 per 0.25 ng/mL increase in donor RAGE level). In addition, RAGE levels remained high for 14 days in those recipients that developed severe graft dysfunction. Recipients may be at higher risk for developing PGD if they receive transplanted organs that have higher levels of soluble RAGE prior to explantation. Moreover, the clinical and pathologic abnormalities associated with PGD posttransplantation are associated with increased RAGE expression. These findings also raise the possibility that targeting the RAGE signaling pathway could be a novel strategy for treatment and/or prevention of PGD.

Dapsone-induced Hemolytic Anemia in Lung Allograft Recipients

PURPOSE Gastric fundoplication (GF) for gastroesophageal reflux disease (GERD) may protect against the progression of chronic rejection in lung transplant (LT) recipients. However, the association of GERD with acute rejection episodes (ARE) is uncertain. This study sought to identify if ARE were linked to GERD in LT patients. METHODS This single-center retrospective observational study, of patients transplanted from January 1, 2000, to January 31, 2009, correlated results of pH probe testing for GERD with ARE (≥International Society for Heart and Lung Transplantation A1 or B1). We compared the rates of ARE among patients with GERD (DeMeester Score > 14.7) versus without GERD as number of ARE per 1,000 patient-days after LT. Patients undergoing GF prior to LT were excluded. RESULTS The analysis included 60 LT subjects and 9,249 patient-days: 33 with GERD versus 27 without GERD. We observed 51 ARE among 60 LT recipients. The rate of ARE was highest among patients with GERD: 8.49 versus 2.58, an incidence density ratio (IDR) of 3.29 (P = .00016). Upon multivariate negative binomial regression modeling, only GERD was associated with ARE (IDR 2.15; P = .009). Furthermore, GERD was associated with multiple ARE (36.4% vs 0%; P < .0001) and earlier onset compared with patients without GERD: ARE proportion at 2 months was 0.55 versus 0.26 P = .004). CONCLUSION In LT recipients, GERD was associated with a higher rate, multiple events, and earlier onset of ARE. The efficacy of GF to reduce ARE among patients with GERD needs further evaluation.

Alcohol primes the airway for increased interleukin-13 signaling.

Background. Despite advances in the field of lung transplantation, the median survival after lung transplant remains below 5 years. Early rejection is a risk factor for the development of chronic rejection. In animal models of transplant tolerance, regulatory T cells (Tregs) can prevent the establishment of rejection. Methods. This study was designed to explore the dynamics of Tregs focally and systemically in lung transplant recipients. Sequential surveillance bronchoscopy results were available in 51 patients with at least four sequential samples recovered from each patient at defined times posttransplant. In 36 individuals, a complete year of follow-up data for BAL was analyzed. In 33 of these individuals had a complete year of follow-up data for peripheral blood monocyte cell specimens were also analyzed. Lung lavage cells were recovered from each bronchoscopy and corresponding blood draw and subjected to polychromatic flow cytometry. The percentage of CD4 lymphocytes, which expressed the intracellular transcription factor FoxP3 was recorded at each point. At each time point, lung biopsy specimens were scored for rejection. Results. Lung Treg frequency was significantly more variable than blood Treg frequency. Treg frequency in the lung was increased in the aftermath of acute rejection. In contrast, lung Treg frequency declined sequentially in patients demonstrating continued quiescence. Mean BAL Treg level integrated over the first transplant year correlated inversely with the degree of acute cellular rejection. In contrast, blood Treg levels demonstrated no correlation with lung pathology. Conclusions. Lung Tregs increase in the setting of acute cellular rejection, whereas declining levels of BAL Tregs correlates with immunologic quiescence.

Surgical Correction of Gastroesophageal Reflux in Lung Transplant Patients Is Associated With Decreased Effector CD8 Cells in Lung Lavages: A Case Series

BACKGROUND Lung transplant (LT) recipients often receive dapsone for Pneumocystis jirovecii pneumonia (PCP) prophylaxis. However, the prevalence of dapsone-induced hematologic toxicity in LT recipients is unknown. We report a high prevalence of hemolytic anemia (HA) associated with dapsone use in LT patients when compared with other patients described in the literature who have been prescribed dapsone prophylaxis. METHODS We performed a retrospective chart review on all LT recipients who received dapsone prophylaxis between 2004 and 2006. Demographics, ideal body weight (IBW), severity of anemia, transfusion requirements, laboratory evidence of hemolysis, serum creatinine and glucose-6-phosphate deyhdrogenase (G6PD) enzyme levels were collected. RESULTS Forty-three patients received dapsone. Ten (22.7%) patients had HA, despite normal G6PD levels. The mean drop in hemoglobin from baseline was 2.7 g/dl (95% confidence interval [CI] 1.9 to 3.5, p < 0.0001). Of those patients with HA, 6 had elevated serum creatinine from baseline. The odds ratio for hemolysis was 4.75 for each 1.0-mg/dl increase in creatinine (95% CI 1.07 to 21.03, p = 0.04). Mean IBW for the HA group was 58.4 kg. A dapsone dose of 100 mg/day orally resulted in a mean dose of 1.7 mg/kg. CONCLUSIONS The prevalence of dapsone-induced HA in LT recipients is 5-fold higher than the reported rate in the population of human immunodeficiency virus (HIV) patients. Individuals with renal failure or low body weight and for whom dose exceeds 1.5 mg/kg may be at increased risk for dapsone-induced HA. Although current CDC guidelines do not recommend adjusting dose by IBW or renal function, we suggest that consideration should be given to these dosing strategies.

The Role of Donor Chronic Alcohol Abuse in the Development of Primary Graft Dysfunction in Lung Transplant Recipients

BACKGROUND Using an experimental model of airway fibrosis following lung transplantation, we recently showed that chronic alcohol ingestion by donor rats amplifies airway fibrosis in the recipient. Associated with alcohol-mediated amplification of airway fibrosis is increased transforming growth factor beta-1(TGFbeta(1)) and alpha-smooth muscle actin expression. Other studies have shown that interleukin-13 (IL-13) modulates TGFbeta(1) signaling during experimentally-induced airway fibrosis. Therefore, we hypothesized that IL-13 is a component of alcohol-mediated amplification of pro-fibrotic mediators in the alcoholic lung. METHODS To test this hypothesis, we analyzed tracheal epithelial cells and type II alveolar cells from control- or alcohol-fed rats, alcohol-treated mouse lung fibroblasts, and human bronchial epithelial cells in vitro for expression of various components of the IL-13 signaling pathway. Signaling via the IL-13 pathway was assessed by measuring levels of phosphorylated signal transducers and activators of transcription-6 (STAT6). In addition, we performed heterotopic tracheal transplantation using control-fed and alcohol-fed donor rats and analyzed tracheal allografts for expression of components of the IL-13 signaling pathway by RT-PCR and immunocytochemical analyses. RESULTS Interleukin-13 expression was detected in type II alveolar epithelial cells and human bronchial epithelial cells, but not in lung fibroblasts. IL-13 expression was decreased in whole lung and type II cells in response to alcohol exposure. In all cell types analyzed, expression of IL-13 signaling receptor (IL-13R alpha(1)) mRNA was markedly increased. In contrast, mRNA and protein expression of the IL-13 decoy receptor (IL-13R alpha(2)) were decreased in all cells analyzed. Exposure to alcohol also increased STAT6 phosphorylation in response to IL-13 and lipopolysaccharide. CONCLUSIONS Data from multiple cell types in the pulmonary system suggest that IL-13 and its receptors play a role in alcohol-mediated activation of pro-fibrotic pathways. Taken together, these data suggest that alcohol primes the airway for increased IL-13 signaling and subsequent tissue remodeling upon injury such as transplantation.

ISHLT Consensus ReportsPrimary Lung Graft DysfunctionReport of the ISHLT Working Group on Primary Lung Graft Dysfunction, part I: Definition and grading—A 2016 Consensus Group statement of the International Society for Heart and Lung Transplantation

BACKGROUND Lung transplantation is associated with a high incidence of gastroesophageal reflux disease (GERD). The presence of GERD is considered a risk factor for the subsequent development of obliterative bronchiolitis (OB), and surgical correction of GERD by gastric fundoplication (GF) may be associated with increased freedom from OB. The mechanisms underlying a protective effect from OB remain elusive. The objective of this study was to analyze the flow cytometric properties of BAL cells in patients who have undergone GF early after transplant. METHODS In a single-center lung transplant center, eight patients with GERD who were in the first transplant year underwent GF. Prior to and immediately following GF, BAL cells were analyzed by polychromatic flow cytometry. Spirometry was performed before and after GF. RESULTS GF was associated with a significant reduction in the frequency of BAL CD8 lymphocytes expressing the intracellular effector marker granzyme B, compared with the pre-GF levels. Twenty-six percent of CD8 cells were granzyme Bhi pre-GF compared with 12% of CD8 cells post-GF (range 8%-50% pre-GF, 2%-24% post-GF, P = .01). In contrast, GF was associated with a significant interval increase in the frequency of CD8 cells with an exhausted phenotype (granzyme Blo, CD127lo, PD1hi) from 12% of CD8 cells pre-GF to 24% post-GF (range 1.7%-24% pre-GF and 11%-47% post-GF, P = .05). No significant changes in spirometry were observed during the study interval. CONCLUSIONS Surgical correction of GF is associated with a decreased frequency of potentially injurious effector CD8 cells in the BAL of lung transplant recipients.