This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluid & Electrolyte, Subject name: Medicine
Pseudohyponatremia can be seen in - 
Select and explain. 
A. Multiple myeloma, B. Diarrhea, C. Vomiting, D. CHF
A: Multiple myeloma
Answer: A: Multiple myeloma 
Explanation: Ans. is 'a' i.e., Multipe myeloma Causes of Hyponatremia* Pseudohyponatremia# Hyperlipidemia# Hyperproteinemia (multiple myeloma, macroglobulinemia)* Dilutional# Hyperglycemia* Hypovolemic hyponatremia : decreased total body sodium with a relatively greater increase in total body water# Heart failure# Chronic renal failure# Hepatic failure or cirrhosis* Euvolemic hyponatremia : Increased Total body water with nearly normal total body sodium# SIADH# Drugs causing DIADH (diuretics, barbiturates, carbamazapine, chlopropamide, clofibrate, opioids, tolbutamide, vincristine psychogenic polydipsia# Beer potomaria# Hypothyroidism# Adrenal insufficiency# MDMA (ecstasy)# Accidental or intestional water intoxication# MDMA, N-methyl-3,4 methylenedioxy amphelamine; SIADH, syndrome of inapproprfate secretion of antidiuretic hormone.# Hyperglycemia is retened by some as pseudohyponumia, but hyperglycemia is acrually a dilutional hyperglycemia.