An Unusual Presentation of Cobblestone Esophagus From Bisphosphonate Use

Cobblestone esophagus is a rare finding that has been previously described in cases of eosinophilic esophagitis (EoE), candidiasis, Barrett's esophagus, or severe reflux esophagitis from distal gastrointestinal obstruction. We describe a case of asymptomatic cobblestone esophagus secondary to bisphosphonate use.  A 67-year-old female was seen in the clinic for evaluation of microcytic anemia that was incidentally picked up on routine chronic disease follow-up. She had no gastrointestinal symptoms. She has been taking oral alendronate 70mg once a week for osteoporosis since a year ago. Barium meal was performed as the patient initially opted for non-invasive testing, which incidentally showed a diffuse "cobblestone" appearance. Subsequent oesophago-gastro-duodenoscopy (OGD) showed diffuse white nodular lesions along the esophagus with a cobblestone appearance but no ulcer or mass. Segmental esophageal biopsies were negative for fungal stain and did not show any pathology. In the absence of infection, eosinophilic esophagitis, and dysplasia, her "cobblestone" esophagus was attributed to bisphosphonate use by diagnosis of exclusion. Alendronate acid was held off, and serial barium meals over the next year showed significant interval improvement.  Bisphosphonates, such as alendronate acid, are commonly associated with drug-induced esophagitis. With the cessation of the offending medication, there was indeed a significant improvement in our patient's serial barium meal. It is important to review the medication list when encountering patients who present with cobblestone esophagus, as some of these patients with drug-induced esophagitis may be asymptomatic clinically.