The kidney is one of the vital organs in the body. Its functions include filtering blood from metabolic waste, removing excess fluid, producing blood pressure-regulating hormones, producing red blood cells, and vitamin D.

We need to know the function of our kidneys because of these vital functions, and because several conditions can affect or reduce kidney function, such as diabetes, hypertension, dehydration, infections, etc.

Kidney function tests are procedures to determine how well the kidneys are working, as well as to detect health problems related to the kidneys. The earlier kidney function disorders are detected, the earlier corrections can be made to avoid further kidney damage.

Kidney function tests can be performed at any time, prioritized for those with symptoms of kidney disorders including:

• Difficulty or pain when urinating (urination) • Blood found in urine (hematuria) • Foamy urine • Increased frequency of urination • Swelling in the legs due to fluid buildup

Kidney function tests that can be performed include: Urine: Urinalysis, analyzing urine which is the fluid waste product of the kidneys, will detect urinary tract infections, diabetes, and other kidney problems. Microalbuminuria, a test to detect small amounts of albumin in the urine which is an early sign of glomerular kidney disorders.

Blood: Urea/Blood Urea Nitrogen (BUN), used to determine the level of urea nitrogen in the blood which is a protein metabolism waste. High urea levels indicate decreased kidney function. Glomerular Filtration Rate (GFR), used to see the kidney's ability to filter metabolic waste and excess fluid in the body. A decrease in GFR indicates kidney function disorders. Blood creatinine, used to determine the level of creatinine in the blood. Creatinine is a waste product of muscle breakdown that will be excreted through the kidneys. An increase in creatinine levels indicates a decrease in kidney function.

Other tests: Ultrasonography, performed to obtain a picture of the kidneys, can be done to detect abnormalities in kidney size, kidney structure, kidney position, etc. CT scan, performed to obtain a detailed picture of the kidneys, to see structural abnormalities or blockages in the kidney's channels.

Author: dr. Odilia Lustriana (Medical Services Doctor PRAMITA Lab Branch M. Toha Bandung)