In brief
Two organs on either side of the spine, under the lower ribs. They remove waste from the blood as urine, balance salt and water, and help control blood pressure.
- An eGFR below 60 suggests that some kidney damage has occurred, and below 15 indicates kidney failure, according to Pathology Tests Explained.
- High blood pressure and diabetes can both lead to kidney disease, according to healthdirect.
- Kidney problems are one cause of fluid retention.
How it works
The kidneys control body chemistry by regulating the amount of salt, water and other chemicals in the body. Their hormones help control blood pressure, red blood cell production and the uptake of calcium from the intestine.
Kidney function is checked with blood and urine tests. Creatinine, a waste product from muscle, is used to calculate the eGFR, an estimate of how well the kidneys filter. Urine tests look for protein or blood. The most common cause of an electrolyte imbalance is kidney dysfunction.
Connections
12 connections on the map. Select a topic to read its page.
Kidneys is affected by
Kidney disease is a complication of type 2 diabetes, according to healthdirect.
Chronic kidney disease is a complication of high blood pressure, according to healthdirect.
Source: healthdirect Australia, High blood pressure (hypertension)
In chronic kidney disease the kidneys no longer filter the blood and remove wastes as well as they should, for three months or longer.
Kidney stones are crystalline stones that form in the kidneys or ureters.
Kidneys helps control
The kidneys help to control your blood pressure.
Source: Better Health Channel (Victorian Government), Kidneys
The kidneys control electrolyte levels, and kidney disease is the most common cause of high potassium.
Sources: Pathology Tests Explained, Electrolytes; healthdirect Australia, Potassium
Kidneys is linked with
Kidney problems are one cause of fluid retention.
The kidneys control electrolyte levels, and the most common cause of an imbalance is kidney damage.
Kidneys supports
Hormones from the kidneys help control red blood cell production.
Source: Better Health Channel (Victorian Government), Kidneys
Kidneys is needed for
The kidneys convert 25-hydroxyvitamin D into calcitriol.
Kidneys is measured by
Creatinine, eGFR and urine tests show how well the kidneys are filtering the blood.
Sources: Pathology Tests Explained, Kidney function tests; Pathology Tests Explained, Creatinine
Kidneys is supported by
Water helps your body get rid of waste products, which the kidneys clear.
Sources: healthdirect Australia, Drinking water and your health; Pathology Tests Explained, Kidney function tests
Lab tests
- Kidney function tests (creatinine and eGFR)Blood and urine tests that show how well your kidneys are clearing waste, including creatinine, eGFR, urea and the urine albumin to creatinine ratio (ACR).
- Electrolytes (sodium, potassium, chloride, bicarbonate)Measures sodium, potassium, chloride and bicarbonate, salts that help regulate heart rhythm, nerves and muscles.
- Magnesium testMeasures magnesium in the blood, and sometimes the urine. Only about 1% of the body's magnesium is in the blood.
- Uric acid (urate)Measures uric acid (urate), a waste product made when the body breaks down substances called purines. It helps diagnose gout.
Medicines and supplements
General education only. Never start, stop or change a medicine without your prescriber.
Sources
Each connection above names its own source. See every source AskBioMap uses.
Summarised from the Better Health Channel, Pathology Tests Explained and healthdirect. Sources read on 13, 16 and 19 October 2026. General education only, not medical advice. Spotted a mistake? Please tell us through the HuBu-Intel contact page.