Spontaneous diffuse bleeding of the gastrointestinal tract in a patient with light-chain deposition disease

Light-chain deposition disease (LCDD) is a rare condition that is characterized by an excessive nonamyloid deposition of light chains in various tissues, which can lead to organ dysfunction. Generally, the kidney is the most affected organ in LCDD, and liver is the most likely affected site in the digestive system. However, LCDD affecting the gastrointestinal (GI) tract is very rare. Here we first report a case who presented with spontaneous diffuse bleeding in the GI tract, with a final diagnosis of LCDD underlying a primary condition of multiple myeloma. This case demonstrated that LCDD can be a rare cause of spontaneous diffuse errhysis in the absence of disseminated intravascular coagulation. A possible differential diagnosis of LCDD should be considered if spontaneous diffuse GI bleeding is encountered at endoscopy, particularly in cases with multiple organs affected. Pathological examinations of light chain deposition in the affected tissues and serum examinations of clonal light chains are indispensable for confirming the diagnosis.