Plasma cell morphology as a trigger for the diagnosis of adult Fanconi syndrome

[摘要] A 76-year-old female presented with history of monoclonal gammopathy of undetermined significance (MGUS). Renal biopsy showednumerous rhomboid crystals within the tubular epithelium, prompting a diagnosis of light chain Fanconi syndrome. Bone marrow biopsyrevealed 10% clonal plasma cells that displayed intracytoplasmic rhomboid crystalline inclusions, fine azurophilic granules (Figure 1A–C;bone marrow aspirate; Wright–Giemsa stain; 100× objective), andAuer rod-like inclusions (Figure 1B,D, arrows). Additionally, crystalstoring histiocytes were observed (Figure 1D,E; bone marrow aspirate;Wright–Giemsa stain; 100× objective).