A Case of Kappa Light-Chain Multiple Myeloma With Auer Rod-Like Inclusions and Snapper-Schneid Granules

In multiple myeloma, plasma cells can display intracellular and intranuclear inclusions. This case report highlights the coexistence of basophilic Snapper-Schneid granules and Auer rod-like cytoplasmic inclusions. A 73-year-old female patient, with a history of hyperlipidemia, rheumatoid arthritis, and hypertension, presented with swelling in both upper extremities. Subsequent evaluations revealed significant proteinuria, hypercalcemia, and atypical plasma cells characteristic of multiple myeloma, with both Auer rod-like inclusions and Snapper-Schneid granules observed. Auer rod-like inclusion bodies are particularly observed in patients with kappa light-chain-type multiple myeloma. The positivity of these bodies for alpha-N-esterase, acid phosphatase, and beta-glucuronidase suggests they are of lysosomal origin. However, the prognostic implications of Auer rod-like inclusions and Snapper-Schneid granules in multiple myeloma remain unclear. Snapper-Schneid granules, described as oval basophilic granules, are associated with immunoglobulin but are not found exclusively in multiple myeloma.