Last Reviewed July 2015 Page 1
Prevent, Detect, Support.
Fact sheet Albuminuria
What is albuminuria? What is proteinuria?
Albumin is a protein in your blood. If your kidneys are damaged and Albuminuria and proteinuria mean In the blood, albumin acts as a carrier albumin leaks into the urine in very similar things. Albuminuria refers and helps to maintain blood volume small or ‘micro’ amounts, this is called to abnormal levels of the protein and pressure. The action of the kidney microalbuminuria. As kidney function called albumin in your urine. While is to filter the blood to remove waste declines the amount of albumin in the albumin is the most common protein products and these filters (known as urine increases, and larger or ‘macro’ found in the urine, there are other glomeruli) prevent large molecules, amounts of albumin may be present. proteins in the urine such as low such as albumin, from passing This is known as macroalbuminuria. molecular weight immunoglobulin, through. If these filters are damaged, lysozyme, insulin and beta-2 The finding of albumin in the urine albumin passes from the blood in microglobulin. Proteinuria refers to may be the first sign of an otherwise to the urine. abnormal levels of all of the proteins silent kidney condition. in the urine, which may or may not include albumin.
What causes albuminuria? What is orthostatic proteinuria? Inflammation or swelling of the kidney Cardiovascular disease is also linked filters is the most common cause of with albuminuria. Damaged blood Sometimes older children have albuminuria. This condition is often vessels may lead to heart failure or orthostatic proteinuria. It is unusual called glomerulonephritis or nephritis. stroke as well as kidney failure. Some in people aged over 30. ‘Orthostatic’ See the ‘Nephritis’ fact sheet for more examples of temporary albuminuria means upright so protein is only lost information. that are often not a sign of significant into the urine when these children kidney damage include: Diabetes and high blood pressure are standing up. Children with this are the two main risk factors for • when it follows strenuous exercise kidney condition do not have kidney albuminuria as they can damage your damage and for reasons that are not • when it only occurs with a fever kidney filters. Older age, weight gain understood, only have proteinuria and certain family backgrounds can • when it occurs only during a urinary when they are active. also increase the risk. tract infection • when it is absent in the morning but occurs later in the day, called orthostatic proteinuria
Connect with us www.kidney.org.au Freecall 1800 454 363 Kidney Health Australia Albuminuria Last Reviewed July 2015 Prevent, Detect, Support. Page 2
What are the symptoms of albuminuria?
In some cases there may be no vessel walls and causes swelling of early signs of chronic kidney disease signs or symptoms linked with this soft tissue areas such as around the (CKD) that can worsen over time. condition. One of the most common eyes and other body parts like the Sometimes there is a large amount symptoms of albuminuria is foamy feet and hands. of protein present yet the underlying appearance or excessive frothing problem may be treatable. Ongoing The amount and type of protein in of the urine. albuminuria usually indicates the the urine reflects the change that presence of serious, underlying kidney When a very high level of albuminuria has occurred to the kidney. A small disease so albuminuria should always is ongoing, it may cause the protein amount of albuminuria that comes be investigated. in your blood to drop. This drop allows and goes is usually not significant fluid to move through the blood but sometimes these low levels are
What tests detect albuminuria?
The preferred method for detecting years if you are obese, smoke, have albuminuria is a test called a urinary cardiovascular disease, have a family albumin:creatinine ratio (urine ACR). history of CKD or are of Aboriginal or This test is performed on a single Torres Strait Islander origin. sample of your urine. Your doctor may Your doctor will also probably suggest ask you to collect a urine sample first you have a blood test to detect the thing in the morning, right after you possible causes for loss of protein. get up (called a first void sample). If this is not practical, your doctor can If the doctor suspects that a child still do the test on a sample of urine has orthostatic proteinuria, two urine collected at any time during the day samples are collected and checked. (called a spot random sample). The first is collected in the morning, right after the child gets up (first If this test result is positive, then your void). The second sample is collected doctor will repeat the test two times throughout the day. If it is orthostatic within the next three months to see proteinuria, the first void sample won’t if you have persistent albuminuria. have any protein but the daytime A urine ACR test should be done at sample will have protein. least once a year if you have diabetes or high blood pressure, and every two
How is albuminuria treated?
Your doctor will monitor the level of of kidney disease cannot be cured diabetes and/or blood pressure. albumin in the urine to find out if it is but progression can be slowed by Your doctor may prescribe ACE increasing or decreasing. Further tests appropriate treatment. inhibitors or angiotensin receptor may be needed to investigate the blockers. These drugs have been In recent years the use of medications cause and extent of kidney damage. In found to protect kidney function such as ACE inhibitors or angiotensin some cases a kidney biopsy is the only while controlling blood pressure. receptor blockers has proved to be way to accurately diagnose the cause effective treatment for reducing If your child has orthostatic of albuminuria. This is done by passing albuminuria. Reducing the amount proteinuria, usually no treatment a needle through your skin into the of albuminuria means an improved is needed. The doctor will test your kidney, and a small piece of kidney outcome whatever the underlying child’s urine after a few months to tissue is removed for examination cause. This treatment has become check for the amount of protein. If the under a microscope by a pathologist. the standard approach in most cases. proteinuria hasn’t changed or if there If the biopsy finds a treatable cause is more protein, your doctor may send If your albuminuria is due to diabetes then the treatment may stop the your child to a kidney specialist. or high blood pressure, the first goal albuminuria. However most types will be better self-management of
Connect with us www.kidney.org.au Freecall 1800 454 363 Kidney Health Australia Albuminuria Last Reviewed July 2015 Prevent, Detect, Support. Page 3
How can albuminuria be prevented?
People at risk of developing CKD need You are at increased risk of CKD if you: • are obese (Body mass index ≥ 30) to have regular check-ups with their • have high blood pressure • are a smoker doctor to detect and treat kidney disease before it worsens. • have diabetes • are 60 years or older • have established heart problems • are of Aboriginal or Torres Strait (heart failure or past heart attack) Islander origin and/or had a stroke • have had an episode of acute kidney • have a family history of kidney failure injury
This is intended as a general For more information introduction to this topic and is not about kidney or urinary meant to substitute for your doctor’s If you have a hearing or Health Professional’s advice. or speech impairment, All care is taken to ensure that health, please contact the information is relevant to contact the National the reader and applicable to Relay Service on our free call Kidney Health each state in Australia. It should be noted that Kidney Health 1800 555 677 or Information Service Australia recognises that each relayservice.com.au person’s experience is individual (KHIS) on 1800 454 363. and that variations do occur in For all types of services treatment and management due to ask for 1800 454 363 Or visit our website personal circumstances, the health professional and the state one kidney.org.au to access lives in. Should you require further information always consult your free health literature. doctor or health professional. Kidney Health Australia gratefully acknowledges the valuable contribution of the Royal College of Pathologists of Australasia for the review of this material.
Connect with us www.kidney.org.au Freecall 1800 454 363