Chronic kidney disease (CKD) develops when the kidneys become less effective over time due to damage. CKD progresses from stages 1–5. Stage 2 indicates mild kidney damage.
A person with CKD might not notice any symptoms in the early stages. However, stage 2 is the first stage at which some people may start to notice the effects of kidney damage.
According to the Centers for Disease Control and Prevention (CDC), around
The National Health and Nutrition Examination Survey found that around 2.8% of people in the United States had stage 2 CKD between 2017 and 2020.
People with stage 2 CKD may not know they have it because symptoms often become clearer at stage 3. However, a doctor might pick up on some signs and symptoms while checking for kidney problems or examining other health issues.
These signs and symptoms may include:
- hypertension, also called high blood pressure
- proteinuria, which is protein in the urine
- urinary tract infections (UTIs)
- hematuria, or blood in the urine
- edema, which is fluid buildup in the hands and feet that causes swelling
Kidney damage may also appear in kidney biopsies and on imaging tests, such as:
CKD develops when the kidneys do not filter blood as efficiently as they should, meaning they cannot remove waste and excess fluid from the body.
Other health conditions may also lead to CKD, including:
Diabetes develops when the body does not produce enough of a hormone called insulin. Insulin helps the body’s cells use glucose, a type of sugar, from the blood. When the body does not produce enough insulin, high blood glucose results. Over time, raised blood glucose can damage the filters in the kidneys.
According to the CDC, around
High blood pressure can damage the kidneys’ blood vessels, affecting how they remove waste and fluid. This can increase fluid in the blood vessels, leading to further elevation in blood pressure.
Other potential causes of kidney disease include:
- kidney infection
- polycystic kidney disease (PKD), a genetic condition that can lead to cysts in the kidneys
- toxic reactions to drugs or heavy metals, such as lead
- autoimmune disorders, such as Goodpasture syndrome, in which the body’s immune system attacks its own healthy organs and tissues
- diseases that affect the whole body, such as lupus or diabetes
- rare genetic disorders, including Alport syndrome
- hemolytic uremic syndrome, a condition in children that causes destroyed red blood cells to build up in the kidneys
- immunoglobulin A (IgA) vasculitis, a condition that causes a buildup of IgA, which is a type of antibody, in blood vessels
- IgA glomerulonephritis, which is a buildup of IgA in the kidneys
- renal artery stenosis, or the narrowing of arteries in the kidneys
Stage 2 CKD
- heart disease
- a family history of kidney disease
A doctor can run various tests to measure how the kidneys work and determine whether a person has CKD.
Estimated glomerular filtration rate (eGFR) test
An eGFR test is the leading indicator of a person’s current stage of CKD, especially if they are not yet experiencing symptoms.
This blood test shows how well the kidneys filter blood. It measures the level of a waste product called creatinine in the blood.
Healthy kidneys remove creatinine, expelling it in the urine. Damaged kidneys will not remove creatinine efficiently, leading to a creatinine buildup in the blood.
After the test, a doctor can then figure out an eGFR. This number indicates a person’s kidney health. People with stage 2 CKD have an eGFR of 60–89. It means the kidneys have a mild loss of function and show signs of damage.
A doctor might request other tests to check the extent of kidney damage and what might be causing it. These tests may include:
- blood pressure tests to rule out hypertension as a cause
- urine tests to assess kidney function, measure the stage of CKD, check for complications, and track kidney-linked health issues, such as:
- kidney infections
- imaging tests to check the physical structure of the kidneys, such as:
- CT scans
- a biopsy, in which a doctor removes a tissue sample from the kidney to examine it under a microscope
A doctor will work with a person who has stage 2 CKD to stop kidney disease from getting worse and control some of the factors that may be driving kidney damage.
Managing high blood pressure
Maintaining healthy blood pressure is vital for kidney disease management. The American Heart Association defines a normal blood pressure reading as
Methods to help manage blood pressure may involve:
- eating low sodium, heart-healthy meals
- maintaining an active lifestyle
- getting enough sleep
- taking any blood pressure medications a doctor has prescribed
Managing blood sugar to offset diabetic kidney disease
A person can check their blood glucose regularly to ensure levels are in normal range. Food choices, exercise, and medications can all help people limit kidney damage from consistently high blood glucose.
A doctor may also test the A1C of a person with stage 2 CKD. An A1C test measures glucose levels over 3 months. It gives a longer-term picture than daily changes in glucose levels.
Healthcare professionals often recommend people with diabetes aim for below
Monitoring, consultation, and cautions
Ongoing monitoring and consultation are crucial for people with stage 2 CKD. A person can check how their results compare to their last doctor’s visit. The goal is to have the same eGFR and urine albumin results as the last test.
People with CKD also need to be monitor their medications. Some common over-the-counter medications, such as nonsteroidal anti-inflammatory drugs like ibuprofen, can cause kidney damage.
A person should speak with a healthcare professional before taking any medications to find out whether they may affect the kidneys.
Because stage 2 CKD does not often cause symptoms, it may not be the condition itself that prompts a visit to a doctor.
However, seeking a medical opinion on potential symptoms of CKD, such as swollen hands or feet and UTIs, is essential, especially for people with diabetes or hypertension.
Stage 2 CKD is a mild form of kidney damage that people may not be aware of until a doctor tests for it. High blood pressure and diabetes are the most common underlying causes of CKD.
Kidney damage does not get better. However, managing diabetes and hypertension and avoiding medications that worsen kidney damage can help people with stage 2 CKD preserve their kidney health for longer.