Discussion
Cobblestone esophagus is an uncommon finding on endoscopy that has been associated with conditions like EoE and candidiasis but these causes were excluded in our patient during endoscopy and biopsy. By diagnosis of exclusion, alendronate acid use was deemed the most likely cause of this patient’s cobblestone esophagus although there is no similar case reported before in literature.
Bisphosphonates, such as alendronate acid, are commonly associated with drug induced esophagitis5 and can cause esophageal irritation by breaching the protective hydrophobic mucosal lining6-7. The cobblestone pattern observed during barium meal and endoscopy is a result of inflammation and edema of the lamina propria and submucosal layers overtime8. The mainstay of treatment for drug induced esophagitis is cessation of the offending medication9. There was indeed significant interval improvement in serial barium meal in our patient upon cessation of alendronate acid. This underscores the importance of reviewing medication list when encountering patients exhibiting cobblestone esophagus, in addition to ruling out the known underlying causes mentioned earlier.
The clinical challenge of this case lies in its atypical asymptomatic presentation of drug induced esophagitis. Patients with drug induced esophagitis frequently complain of symptoms such as retrosternal chest pain which happens in about 70% of the patients, as well as odynophagia and dysphagia9. In our patient, it was first picked up incidentally on barium meal as part of anemia workup before confirming it with endoscopy. With this in mind, it is important to counsel our patients on the correct administration of bisphosphonate10 so as to minimize upper gastrointestinal adverse effect that may initially be asymptomatic and delay timely action before long term side effects are made.