Routine urine examination tells us about the presence or absence of certain substances the glucose, proteins, ketones, nitrites, bilirubin which could be an indication of certain diseases like diabetes mellitus, jaundice, infection etc. Blood in urine could indicate infection, stones etc. Pus cells could indicate infection. Casts could indicate real disease. Crystals like oxalate, urate etc. are seen following high dietary intake of food rich in these minerals. Culture of urine helps us to isolate bacteria causing infection.