Glossary

Lost in medical phrases? We explain the most important medical terms for you to know and be fluent in renal language.

The presence of albumin (a blood protein) in the urine is called albuminuria. Normally, albumin should not be found in the urine since it is too large a protein to pass the renal filters. However, if the renal filter function is impaired, albumin can pass from blood to urine, which is called albuminuria.

The diagnosis of albuminuria is done with a urine test that measures the concentration of albumin in the urine. It is important to diagnose albuminuria early as it may be an indicator of kidney disease at an early stage. Treating the possible underlying disease or kidney issues can contribute to slowing down or stopping the progression of albuminuria. Patients with diabetes, hypertension, excess weight, or metabolic syndrome should be routinely tested for albumin in the urine to detect possible kidney disease early on. Timely interventions can slow down its progression, or even stop it completely.

Type 1 diabetes is caused by an auto immune response of the body. The insulin producing organ, the pancreas, is attacked and destroyed by the body’s own immune cells. Consequently, the body is not capable of producing insulin anymore. Type 1 diabetes usually occurs in childhood or adolescence and requires insulin therapy as it is not produced in the body anymore.

Type 2 diabetes occurs if the body loses the ability to use its insulin effectively or to produce sufficient amounts of it. It is usually diagnosed in middle age or elderly people, but more and more frequently even in younger people. Therapy for type 2 diabetes usually comprises dietary restrictions, physical activity, and medication. Insulin therapy may be required in later stages of the disease. A healthy lifestyle and losing excess weight can attenuate or slow down type 2 diabetes.

eGFR, short for estimated glomerular filtration rate, is a measure for renal function. This value indicates the kidneys’ capability of removing metabolic waste products from the blood. The measuring unit for eGFR is millilitre per minute per 1.73 square meters of body surface.

eGFR is based on a blood test that measures creatinine in the blood. Creatinine is a waste product of muscle metabolism which is removed from the blood by the kidneys and excreted via the urine. If kidney function declines, the blood creatinine concentration rises.

eGFR is calculated based on the blood creatinine value and factors like age, gender, ethnicity, and weight. There are different formulas for calculating eGFR to be used by doctors and labs. The CKD-EPI formula is the recommended formula.

The normal eGFR value may vary depending on age, gender, and physical shape. A value of 90 or higher is considered normal. A value below 60 can point to impaired kidney function and requires further tests to be ordered by a doctor.

Creatinine is a waste product of muscle metabolism that is continuously produced by the muscles. It passes on to the blood and is removed from the body by the kidneys. An elevated blood creatinine value may point to impaired renal function as the kidneys may be losing the capacity to fully remove creatinine from the body.

For measuring blood creatinine, a blood sample is taken and analysed in a lab. There are different methods for measuring creatinine, including enzymatic and non-enzymatic methods. The creatinine value is affected by different factors like age, gender, muscle mass, diet, and medication.

For calculating creatinine clearance, both the creatinine in the blood and in the urine are measured. Creatinine clearance is then calculated by dividing the amount of creatinine that is excreted per minute by the blood creatinine concentration. A 24-hour urine collection is usually required for the determination of creatinine clearance

Creatinine clearance is the more demanding method for estimation of renal function. Usually, eGFR is preferred.

Point-of-Care-Tests (POCT) are medical tests which can be performed directly at the location of medical care, near the patient and without the need of sending samples to a lab. These tests provide results quickly and allow health care professionals to make instant decisions on therapies.

POCTs can be used in different circumstances, e.g. doctors’ offices, clinics, emergency rooms, ambulatory care facilities, and even in home care. There are multiple kinds of POCTs, including tests for controlling blood sugar, pregnancy, infections, drug and alcohol consumption and even diagnosis of heart attacks or strokes.

The main advantage of POCTs is the rapid provision of results, which can be key for patient care or managing epidemic infections. They may also be more cost effective than regular tests as they require less time and resources for sample preparation and analysis.

Retention marks the build-up of waste products and fluids in the body due to an impaired capability of the kidneys to remove them. Especially in later stages of chronic kidney disease the retention of waste products and fluids can result in swellings, fatigue, nausea, and itching. Therapies may be required to support renal function and to reduce the build-up of waste products and fluids in the body.

The transparent part of the blood that remains after the removal of blood cells and coagulation factors. The serum contains a multitude of substances such as electrolytes, enzymes, hormones, proteins and metabolic waste products which are important for diagnosis and monitoring of different diseases, including chronic kidney disease. Since the kidneys are responsible for balancing electrolyte metabolism and removing metabolic waste products, their failure may result in elevated levels of waste products such as urea, creatinine, and uric acid in serum.

Chronic kidney disease can cause metabolic disorders that in turn may affect serum concentrations of other substances. Measuring their values in patients with chronic kidney disease helps to assess the severity level of the disease and to make plans for the appropriate therapy.

The UACR value (short for Urine Albumin Creatinine Ratio) is a medical test for diagnosis and monitoring of kidney diseases. It is a measure for the ratio of albumin to creatinine in urine.

An increased UACR value points to a possible renal disease, in particular to a disease called proteinuria, which is characterized by damaged renal tissue and the leakage of blood proteins such as albumin into the urine.

The UACR test is usually performed when a person is at risk of renal impairment, e.g. patients with diabetes or hypertension. When used as a screening test, it is helpful for identifying people with an increased risk of renal disease.

An elevated UACR value may point to kidney disease at an early stage which has to be treated to prevent further damage.