It has been reported that some patients have been misdiagnosed with Stomach Flu, when in fact the correct diagnosis in their specific case was Kidney Stones.
Kidney stones also known as renal caliculi are deposits of minerals and salts that form inside the kidneys. When kidney stones pass into the ureter outside of the kidney they cause symptoms such as severe sharp pain in the side and back, pain that radiates to the lower abdomen and groin, pain that comes in waves and fluctuates in intensity, pain or burning sensation while urinating. It can be mistaken for other conditions such as appendicitis, lower back pain, urinary tract infections and gastroenteritis.