Gastrointestinal Manifestation of Light Chain Deposition Disease: Beware of the Snakeskin Duodenum.

Gastrointestinal manifestations of light chain deposition disease are exceedingly rare and are characterized by gastrointestinal bleeding, nutritional deficiencies and protein-losing enteropathy. Diagnosis is challenging due to nonspecific symptomatology and indolent disease progression. We describe the case of a 69-year-old woman presenting with melena, chronic diarrhea, and recurrent sepsis. Gastroscopy revealed a highly unusual snakeskin appearance of the duodenum, with histopathology and immunofluorescence confirming light chain deposition disease. This case highlights the importance of prompt biopsy acquisition, hematological evaluation and assessment of extragastrointestinal involvement in facilitating a timely diagnosis, particularly when an underlying lymphoplasmacytic lymphoma is a possible driver of disease.