A Round-Shaped, Radio-Opaque Foreign Body on Chest Radiograph, Identified as an Intact Lanthanum Carbonate Tablet

Abstract Background: Lanthanum carbonate is a phosphate binder in the form of a chewable tablet, which is commonly prescribed in chronic kidney disease patients. We reported an unusual radio-opaque foreign body which was accidentally found in a chest X-ray of an elderly female patient and later identified as an intact lanthanum carbonate tablet. Case Presentation: A 60-year-old woman with end stage renal disease, receiving lanthanum carbonate was found having a coin-shaped, homogeneous radiopaque foreign body in the position of esophagus of her chest X-ray. Due to awareness of mimicking other conditions (e.g. button battery or coin ingestion), urgent endoscopy was performed. An intact lanthanum carbonate tablet was found in the upper stomach and was removed successfully. Conclusion: Physicians should be aware of unchewed lanthanum carbonate tablets when a metallic-like object is detected on chest radiograph of a lanthanum carbonate user. Also, prescription of chewing medication should be cautioned particularly in an elderly female patient.