Introduction
Lanthanum carbonate is one of the most potent phosphate binders. It binds dietary phosphate and forms insoluble complexes which are eliminated through the gastrointestinal tract. It is used to prevent elevation of serum phosphate especially in dialysis dependent patients. Patients treated with lanthanum carbonate show depositions predominantly in the gastric mucosa. Those depositions can be seen on gross examination as white spots, ringlike white discoloration, or diffuse white discoloration of the mucosa. Scanning electron microscopy and energy dispersive X-ray can be used to further identify lanthanum and phosphate deposition in the mucosa. The whitish depositions can be seen as early as three months after first taking lanthanum carbonate. They also seem to intensify over time. There is a positive correlation between the amount of lanthanum intake and its accumulation. The depositions seem to persist for a long time.
We herein report a case of gastric lanthanosis in a patient with a cessation of lanthanum carbonate over 7 years, supporting the concept of permanent depositions. This could suggest that the depositions are irreversible or at least persist for a long time. They also seem to lead to symptoms even years after cessation. Clinicians should be aware of this fact and specifically look for specific endoscopic changes and take biopsies if they have a patient with epigastric discomfort and a history of lanthanum medication.