Urinalysis, 4000 BC – The first step in laboratory medicine

Comedian Rodney Dangerfield once said, “I drink too much alcohol. The last time I gave a urine sample, it had an olive in it.” In fact, urinalysis, or the examination of urine for medical diagnosis, has a history that is both wild and serious.

Beginning around 4000 BC, Sumerian physicians recorded urine analyses on clay tablets. Sanskrit medical texts dating roughly from 100 BC describe at least 20 different types of urine. In ancient India, doctors were aware that people affected by what we now call diabetes produced urine that tasted sweet and attracted ants.

Before modern medicine, visual examination of urine was called uroscopy. Medieval doctors elevated uroscopy to an almost magical art by holding and rotating the matula (a bladder-shaped glass vessel) before the patient's eyes before predicting the disease's outcome. Some physicians began making diagnoses without ever seeing the patient. During the Renaissance, uroscopy was even used for fortune-telling and predicting the future.

Today, we know that a large number of white blood cells detected in a urine sample may indicate a urinary tract infection. Hematuria, or the presence of red blood cells in urine, may indicate a kidney stone, kidney trauma or a tumor in the urinary tract (which includes the kidneys, ureters, urinary bladder, prostate and urethra). Diabetes is the main cause of glucose (sugar) in urine. Other urine tests may be used to help diagnose liver or thyroid disease.

Physiologist J. A. Armstrong: “From a window through which physicians thought they could see the inner workings of the body, urine led to the beginnings of laboratory medicine. As the role of physicians rose, the importance of urinary diagnosis was exaggerated, and by the seventeenth century the use of uroscopy had gone far beyond reason."

Description of the article image: In the work by Dutch painter Gerrit Dou (1613-1675), a doctor is depicted looking at a urine flask (1653).

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