Pathology · patient case with 4 questions
Bone pain, anemia and an enlarged tongue
Patient: 64-year-old man referred by his physician.
Chief complaint: His tongue feels too big for his mouth and he is exhausted.
History: Six months of back pain, fatigue and recurrent infections. Recent labs show anemia, hypercalcemia and elevated creatinine. Skull radiographs show multiple well-defined punched-out radiolucencies.
Findings: Enlarged tongue with lateral scalloping from tooth indentations. Pallor of the oral mucosa. Working diagnosis: multiple myeloma with systemic AL amyloidosis.
Question 1
Which cell type proliferates in this condition?
Show answer and explanation
Correct answer: D. Plasma cells
- A. Histiocytes are the proliferating cell in Langerhans cell histiocytosis, which can also produce punched-out lesions but is a different disease.
- B. T-cell malignancies are a separate group of lymphoid neoplasms.
- C. Osteoblasts form bone. In myeloma, osteoclast activity is upregulated and osteoblast activity suppressed, which is why the lesions are purely lytic and bone scans are often falsely negative.
- D. CORRECT. Multiple myeloma is a malignant clonal proliferation of PLASMA CELLS in the bone marrow, secreting a monoclonal immunoglobulin (the M protein).
Question 2
Which oral finding in this patient is explained by the amyloid deposition?
Show answer and explanation
Correct answer: C. Macroglossia
- A. Geographic tongue is a benign idiopathic migratory glossitis unrelated to amyloid.
- B. Median rhomboid glossitis is a candidal depapillated patch on the midline dorsum.
- C. CORRECT. Free monoclonal light chains deposit in tissue as AL amyloid. In the tongue this produces MACROGLOSSIA — a firm, enlarged tongue, often with lateral scalloping, sometimes with nodules or haemorrhagic bullae. It is one of the classic oral clues to systemic amyloidosis.
- D. Ankyloglossia is a congenital short lingual frenum.
Question 3
What does amyloid deposition in the myocardium produce?
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Correct answer: D. A restrictive cardiomyopathy with impaired diastolic filling
- A. Dilated cardiomyopathy follows alcohol, viral myocarditis, or ischemia — the ventricle enlarges and contracts poorly, the opposite geometry.
- B. The walls look thickened on echocardiography, a pseudohypertrophy, but true HOCM is a genetic sarcomeric disorder with asymmetric septal hypertrophy and outflow obstruction.
- C. Amyloid affects the myocardium diffusely rather than producing isolated valve lesions.
- D. CORRECT. Amyloid infiltrates between myocytes and stiffens the ventricular wall. The heart cannot relax and fill, giving a RESTRICTIVE cardiomyopathy with diastolic dysfunction and, eventually, heart failure. This is the leading cause of death in AL amyloidosis.
Question 4
Bence Jones protein testing is performed on which specimen?
Show answer and explanation
Correct answer: C. Urine
- A. Serum protein electrophoresis detects the M-spike in blood, and the smear may show rouleaux, but Bence Jones protein specifically is a urine finding.
- B. CSF is not used in myeloma workup.
- C. CORRECT. Bence Jones proteins are free monoclonal immunoglobulin LIGHT CHAINS. They are small enough to pass the glomerulus and appear in the URINE, detected by urine protein electrophoresis and immunofixation. They are a major contributor to the renal failure of myeloma.
- D. Saliva has no role in the diagnosis.