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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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M-spike in multiple myeloma is due to?
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The correct answer is  In Multiple myeloma laboratory analyses reveal increased levels of Igs in the blood and/or light chains (Bence-Jonesproteins) in the urine. The most common monoclonal Ig ("M protein") is IgG (approximately 55% ofpatients), followed by IgA (approximately 25% of cases).