Esophageal capsule endoscopy and Barrett's esophagus: where are we in 2013?

ଝ Cápsula endoscópica esofágica y esófago de Barrett: ¿dónde estamos en el 2013? Capsule endoscopy (CE) is the diagnostic technique of choice for the study of small bowel (SB) pathology. Its high diagnostic performance enables the identification of lesions that, even a few years ago, were under-diagnosed or discovered late. Initial studies in the esophagus showed low cost-effectiveness for capsule endoscopy of the SB, 1 with the exception of the study by Ramírez et al. 2 with string-capsule endoscopy using the PillCam ® SB. Their study demonstrated a high cost-effectiveness, close to 100%, but it was not supported or validated by further studies. For this reason, esophageal capsule endoscopy (ECE) was designed specifically for the study of that portion of the digestive tract, with 2 lenses and greater image capacity. This capsule (initially the PillCam ® ESO1 and later the ESO2) was soon proposed as a useful tool for the study of chronic gastroesophageal reflux disease (GERD) (mainly for the diagnosis and follow-up of Barrett's esophagus [BE]) and in the screening for esophageal varices in portal hypertension. Different studies carried out with the PillCam ® ESO1 and later with the ESO2 in patients with suspected or known GERD and BE have had these main disadvantages: (1) difficulty in complete visualization of the Z line, improved with the right lateral decubitus position; (2) inability to employ local staining techniques (methylene blue or Lugol's solution), unlike upper gastrointestinal (UGI) endoscopy; and (3) the impossibility to take biopsies and thereby know the grade of dysplasia associated with intestinal metaplasia. The majority of published case series comparing the PillCam ® ESO and UGI endoscopy have reported a high specificity and negative predictive value of the capsule for BE screening. However, its sensitivity was considerably low, it had high interobserver variability, and it was not cost-effective in short BE, making it unrecommendable in these patients. A later meta-analysis of more than 600 patients with GERD concluded that ECE had moderate sensitivity and specificity for diagnosing BE and that UGI endoscopy should continue to be the gold standard in these patients. 5 This issue of the Revista de Gastroenterología de México has published a study by Domingos et al. 6 that compares ECE with methylene blue (MB) chromoendoscopy following a regular UGI endoscopy in 21 patients with BE that underwent Nissen fundoplication with follow-up. The authors concluded that ECE appears to be a good method for …