A Triad of Telltale Clues: Macroglossia Raccoon Eye and Nerve Compression Unveil Amyloid Light Chain Amyloidosis.

Systemic amyloid light chain (AL) amyloidosis is a rare but potentially fatal disorder caused by deposition of misfolded immunoglobulin light chains, often presenting with vague, nonspecific symptoms that delay diagnosis. We report a diagnostically striking case of a 65-year-old male presenting with progressive tongue enlargement, periorbital purpura, submandibular swelling, and a prior history of carpal tunnel syndrome-classic yet under-recognized features of AL amyloidosis. Despite negative urine immunofixation and Bence-Jones proteinuria, the markedly elevated free lambda light chains and an abnormal kappa/lambda ratio raised clinical suspicion. Bone marrow biopsy revealed 25% plasma cells with lambda restriction and t(11;14) translocation, confirming AL amyloidosis associated with plasma cell myeloma. Treatment with a daratumumab-, bortezomib-, and dexamethasone-based regimen led to dramatic clinical improvement. This case emphasizes the importance of recognizing subtle external manifestations as early diagnostic clues in AL amyloidosis, especially in the absence of classical laboratory markers. Timely recognition can significantly improve outcomes in a condition where therapeutic delay can be devastating.