subjective myalgias; severe-symptomatic hypercalcemia; persistent flu-like symptoms; proteinuria; IgA-Kappa MM (multiple myeloma); Initial information received on 30-Dec-2020 regarding an unsolicited valid serious case issued from a literature article.   Discussion: Our case is unique in that the patient initially had anormal serum calcium level that had increased rapidly to over 22 mg/dl within a period of 24 hours, had no renal failure or any bone involvement; and had a normal quantitative serum light chain measurement. It is theorized that the inactivated influenza vaccine given prior to presentation unmasked an atypical presentation of MM (Multiple Myeloma). This may be attributed to a vaccination induced cytokine storm, especially IL-6 mediated (Interleukin), that may be the key in the pathophysiology of hypercalcemia related to MM (Multiple Myeloma).  This case involves a 65 years old female patient who had IgA (immunoglobulin)-kappa mm (multiple myeloma) (plasma cell myeloma), subjective myalgias (myalgia), severe-symptomatic hypercalcemia (hypercalcemia), persistent flu-like symptoms (influenza like illness) and proteinuria, after receiving vaccine INFLUENZA VACCINE.  Medical history, medical treatment(s), vaccination(s), concomitant medication(s) and family history were not provided.  On an unknown date, the patient received a dose of suspect INFLUENZA VACCINE produced by unknown manufacturer (lot number and expiration date not reported) via unknown route in unknown administration site for prophylactic vaccination.  On an unknown date, the patient had severe-symptomatic hypercalcemia (hypercalcemia, non-serious), within a period of 24 hours after vaccination.  On an unknown date, the patient presented with serious subjective myalgias (myalgia) 5 days following vaccination and was hospitalized for this event.  Vital signs were stable. CBC (complete blood count) and BMP (basic Metabolic Panel) were unremarkable.  Serum calcium was 10.8 mg/dl.   The patient was discharged on supportive therapy.   On an unknown date, patient presented a day later with persistent flu-like symptoms (influenza like illness, non-serious event, latency unknown).   Laboratory revealed serum calcium being above 22 mg/dl, normal renal function, total protein, albumin, ACE (angiotensin-converting enzyme) levels; clear UA (urine analysis) with no albuminuria; low PTH (parathyroid hormone) and 1, 25-(OH)2 (dihydroxy)-Vitamin D3 levels; elevated PTHrP (Parathyroid hormone-related protein) & viscosity levels.   On an unknown date, 24-hour urine collection of patient revealed non-serious proteinuria (550 mg), unknown latency following vaccination. Peripheral blood smear revealed rouleaux formation. CT (computerized tomography) scans of the chest, abdomen and pelvis revealed no obvious malignancy.   Quantitative immunoglobulins revealed elevated IgA (immunoglobulin A) (2415 mg/dl), and concurrent suppression of IgG (immunoglobulin G) and IgM (immunoglobulin M) levels. Quantitative serum light chain measurement revealed normal levels of kappa and lambda, with an elevated Kappa: Lambda ratio of 2:1.  On an unknown date, the patient's SPEP (serum protein electrophoresis ), UPEP (urine protein electrophoresis) and serum immunofixation test revealed serious IgA-Kappa MM (plasma cell myeloma, medically significant event, latency unknown).  Patient was treated with aggressive intravenous crystalloids, loop diuretics, calcitonin, pamidronate, and hemodialysis. Her calcium subsequently normalized to 10.1 mg/dl.   Bone-marrow biopsy revealed intracytoplasmic kappa-restricted monoclonal plasma cells that occupied 40% of the marrow. Bone survey was negative for lytic lesions.   Patient was started on bortezomib, lenalidomide, dexamethasone and monthly zoledronic acid.  At the time of reports, the patient has not recovered from the event plasma cell myeloma, as it was reported that  she has not attained remission from myeloma yet. While the patient recovered from the event hypercalcemia and myalgia.   The outcome was unknown for the events Influenza like illness and proteinuria.  There will be no be information on the batch number for this case.; Sender's Comments: This case concerns a 65 years old female patient who had plasma cell myeloma, hypercalcemia, influenza like illness and proteinuria, after vaccination with INFLUENZA VACCINE. The time to onset is compatible. However, patient's medical condition at the time of vaccination and lab tests ruling out alternate etiologies were not reported. Based upon the reported information, the role of individual vaccine cannot be assessed.