It is important to understand the nature of this condition in order to take the proper steps for managing it.
What is CKD
CKD is a condition in which kidney function gradually declines over time.
As CKD progresses, eventually the kidneys lose their ability to function. In this case, renal replacement therapy (RRT) is required. RRT consists of dialysis or kidney transplant. It is estimated that CKD affects approximately 15% of the general adult population in the US. CKD is recognized as a growing epidemic all over the world that has a major impact on quality of life.
Structure of kidneys
The kidneys are two bean-shaped organs that are about 4-5 inches in length and located on the back of the abdomen on either side of the spine.
Each kidney is made up of around a million small functional units called nephrons. Each nephron is subdivided into two parts:
- The renal glomerulus, which filters the blood
- The renal tubule, which puts important substances back into the blood and excretes waste in the urine
Function of kidneys
The functions of the kidneys include:
- Filters the blood to keep nutrients and eliminate wastes
- Maintains sodium and potassium Balance
- Maintains fluid balance
- Controls body’s pH
- Regulates blood pressure
- Makes red blood cells
How the doctor measures kidney health:
- Nitrogen levels in the blood: Increased nitrogen in the blood is called azotemia, which is indicative of poor kidney function
- Creatinine levels in the blood: Increased creatinine in the blood is called creatinemia, which is also indicative of poor kidney function
- Creatinine clearance: This is a measure of how much creatinine is removed from the blood by the kidneys per minute. Reduced creatinine clearance indicate reduced kidney function.
Serum creatinine levels are useful for calculating the estimated glomerular filtration rate (eGFR), which gives an indication of how efficiently the kidneys filter blood over a period of time. The GFR is one of primary indicators of kidney function.
Causes of CKD
There are a number of conditions that affect kidney function and over time, can lead to CKD.
The most common conditions associated with CKD are hypertension and diabetes mellitus. Others include pyelonephritis, glomerulonephritis, polycystic kidney disease, congenital/ genetic kidney diseases, and chronic obstruction of the urinary tract. In addition to these conditions, risk factors that increase the likelihood of developing CKD include obesity, high cholestero levels, and urinary tract infections.
Stages of CKD
The stages of CKD are defined using a model based on glomerular filtration rate (GFR).
GFR is measured in milliliters per minute (ml/min). This measurement is obtained by evaluating the volume of Plasma “cleared” of a given substance (in this case, creatinine) in a given amount of time by the kidney. GFR slows as kidney function declines.
Stage 5 is defined as the end stage, signifying almost complete loss of kidney function. Once this stage is reached, the nephrologist will start to prepare the patient for renal replacement therapy (dialysis or kidney transplant).
Treatment of CKD
The first step for treating CKD is identifying and treating the cause. When CKD is caused by a known pre-existing condition, such as diabetes, steps should be taken to address that condition to reduce further kidney injury. However, CKD is a progressive illness that may advance independently from the original cause. This is why doctors and patients need to work together to slow down the progression the progression of the disease and minimize complications. Medical and dietetic interventions may preserve kidney function for a longer period of time and help the patient maintain better quality of life.
Interventions for CKD may include:
- Medical nutrition therapy (MNT)
- Drug therapy of symptoms and complications (fluid overload, bone alterations, anemia, metabolic acidosis, diabetes, high cholesterol levels etc.)
- Preparation for renal replacement therapy (dialysis or transplant).
These measures should also be accompanied by additional Lifestyle changes, such as quitting smoking and exercising regularly.