Thursday, July 03, 2008
Pulmonary Medicine, October 2005
In This Journal ScanThe New England Journal of MedicineThoraxChestAmerican Journal of Respiratory and Critical Care Medicine
Pulmonary Medicine, October 2005 Journal Scan
FromThoraxOctober 2005 ( Volume 60, Number 10 )
Pepsin Like Activity in Bronchoalveolar Lavage Fluid Is Suggestive of Gastric Aspiration in Lung AllograftsWard C, Forrest IA, Brownlee IA, et al
Thorax. 2005;60(10):872-874
Bronchiolitis obliterans (BO), the pathologic correlate of chronic allograft rejection, is the entity that is the most common cause of a patient's demise beyond the first post-lung transplant year. This remains 1 of the major reasons why outcomes after lung transplantation continue to lag behind that of other solid organ transplants. As yet, there are no proven effective therapies for BO. Any intervention that might reduce the incidence of BO might have a significant impact on survival. Similarly, early identification of treatable risk factors could have significant long-term benefits. One such risk factor appears to be chronic aspiration. For a number of reasons lung transplant recipients might be at higher risk for aspiration. Specifically, vagal innervation might be disrupted as a result of the surgery and the calcineurin inhibitors are known to reduce gastric motility. Most of the work highlighting the potential association of BO with gastroesophageal reflux disease has come from the group at Duke.[1-4] It is therefore gratifying that another group has produced data consistent with that of the Duke groups, which lends further credence to the association.
In this article, from the British group at Newcastle upon Tyne, the authors looked at levels of pepsin in the bronchoalveolar lavage samples of 13 lung transplant recipients. These patients were 3-87 months out from their transplants. All of them were on standard triple immunotherapy, 10 were taking prophylactic proton pump inhibitors, and all were free from any symptoms suggestive of gastroesophageal reflux disease. They compared the pepsin levels of these patients to those of 4 normal nonsmoking controls (who they somehow talked into undergoing bronchoscopy!). These controls were invaluable as they underscore the importance of the results found in the patients, specifically the levels of pepsin in the controls were < 1 ng/mL vs 109 ng/mL in the patients (range, 35-1375). Small numbers perhaps, big difference definitely, and a P value of .003 to underscore this.
The scary implication of this study is that all lung transplant recipients aspirate and can remain symptom-free, acid-free, and still potentially suffer the deleterious consequences of proteolytic activity in the lungs. This study raises a number of questions. First, is it possible that enzymatic activity precipitates an exaggerated or ongoing immune response? Could it be that BO is not an immunologic injury after all? What is needed to validate these findings is a study showing a correlation between bronchoalveolar lavage pepsin levels and the subsequent development of BO. A retrospective study showing that fundoplication halts or reverses BO has already been performed by the group at Duke[4]. .. food for thought indeed!ReferencesDavis RD, Lau CL, Eubanks S, et al. Improved lung allograft function after fundoplication in patients with gastroesophageal reflux undergoing lung transplantation. J Thorac Cardiovasc Surg. 2003;125:533-542.Lau CL, Paler SM, Howell DN, et al. Laparoscopic antireflux surgery in the lung transplant population. Surg Endosc. 2002;16:1674-1678.O'Halloran EK, Reynolds JD, Lau CL, et al. Laparoscopic Nissen Fundoplication for treating reflux in lung transplant recipients. J Gastrointest Surg. 2004;8:132-137.Cantu E, Appel JZ, Hartwig MG, et al. Early fundoplication prevents chronic allograft dysfunction in patients with gastroesophageal reflux disease. Ann Thor Surg. 2004;78:1142-1151.
Abstract
This is a part of article Pulmonary Medicine, October 2005 Taken from "Erectile Disfunction Medication" Information Blog
Labels: pharmacology
