الفهرس 
Interstitial lung diseases.Only 14 pages are availabe for public view
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Abstract
Gastroesophageal reflux disease is defined as a “condition that develops when the reflux of stomach contents causes troublesome symptoms and/or complications. Heartburn is the most common symptom of GERD. Between 20 and 40 percent of those experiencing common heartburn are predicted to actually have a diagnosis of GERD. In addition to heartburn, regurgitation and difficulty of swallowing are common GERD symptoms (Vakil et al., 2006). The histological counterpart of interstitial lung diseases are areas of fibrosis of various ages interspersed with normal lung. This pattern could be explained by repeated episodes of lung injury followed by abnormal wound healing responses (Raghu, 2008). The cause of the initiating alveolar epithelial injury is unknown, but postulated mechanisms include immunological, microbial, or chemical injury, including aspirated gastric refluxate. Reflux is promoted by low basal pressure in the lower esophageal sphincter and frequent relaxations, potentiated by hiatus hernia or esophageal dysmotility (McCombs, 2006). In susceptible individuals, repeated microaspiration of gastric refluxate may contribute to the pathogenesis of ILDs. Microaspiration of nonacid or gaseous refluxate is poorly detected by current tests for gastroesophageal reflux which were developed for investigating esophageal symptoms. Further studies using pharyngeal pH probes, high-resolution impedance manometry, and measurement of pepsin in the lung should clarify the impact of reflux and microaspiration in the pathogenesis of ILDs (Simpson, 2010).