A 60-year-old man came to emergency with sudden-onset cough with yellow sputum production and dyspnea.He is taking amlodipine for hypeension. Chest X-ray shows a left upper lobe alveolar infiltrate and investigations shows Hb of 6g/dL, BUN of 60 mg/dL, Creatinine of 2.8 mg/dL, Calcium of 12.3 mg/dL, total protein of 9 g/dL and albumin of 4.2 g/dL.On Echocardiogram dilated hea is seen and peripheral neuropathy is also present. Most common cause of death in the above described disease is:

Patient is having multisystem illness pointing to the diagnosis of Multiple myeloma which is causing amyloidosis leading to above clinical manifestation Components of end organ damage in multiple myeloma:C - Hypercalcemia > 11 mg%R - Renal failure: Uremia (Creatinine > 2 mg%)A - AnemiaB - Bony Lytic lesions and not bleeding manifestations. Most frequent cause of death in multiple myeloma is infection (24 to 52% patients) and renal failure (20% of patients). Most common organism involved: Gram negative bacilli > Staph. aureus > Capsulated organisms. Note: Extra edge Cytokines involved in pathogenesis of Multiple myeloma : IL-6 Cause of renal failure in multiple myeloma : Hypercalcaemia > Amyloidosis MC infection in M.M. : Pneumomia Anion gap is reduced in multiple myeloma. Bone marrow biopsy- allow evaluation of the percentage of plasma cells in bone marrow and aid in diagnosis of multiple myeloma Multiple myeloma is associated with amyloid AL. Light chains most commonly deposit in the hea, kidneys, liver, and nervous system, causing organ dysfunction. Biopsy- shows classic eosinophilic material that, when exposed to Congo red stain, has a characteristic apple-green birefringence. Best test for prognosis of multiple myeloma : serum Beta 2 microglobulin Inclusion bodies seen in plasma cells in multiple myeloma : Dutcher bodies : Intranuclear Russell bodies : Intracytoplasmic