The hardest part of my job is not treating kidney disease. It is explaining to someone who feels perfectly well that their kidneys have been losing function for years.
Chronic kidney disease is quiet by design. The kidneys have far more capacity than daily life requires, so as nephrons are lost the remaining ones work harder and keep the blood chemistry looking acceptable. That compensation is remarkable, and it is also why the condition is so often found late, in a routine blood test done for something else entirely.
This article covers what the early signs actually look like, what appears later, and which two tests find the problem while there is still a great deal to protect.
This information is educational and does not replace an evaluation by your own physician.
Why kidney disease stays silent
Each kidney contains around a million nephrons. You can lose a large share of them and still show normal blood work, because the survivors increase their individual workload to compensate.
That adaptation has a cost. The overworked nephrons are under higher pressure, which damages them faster, so the process tends to accelerate once it is underway. By the time symptoms appear, the compensation has been exhausted, and what caused it cannot be undone.
This is not a reason for alarm. It is a reason for testing.
Early signs that get dismissed
These are subtle, and every one of them has other explanations. That is exactly why they get attributed to age, stress or poor sleep rather than to the kidneys.
Fatigue that rest does not fix. Failing kidneys produce less erythropoietin, the hormone that signals the bone marrow to make red blood cells. The resulting anemia causes a tiredness that does not respond to sleeping more.
Waking at night to urinate. Losing the ability to concentrate urine overnight is an early change. Getting up once may be nothing; a new pattern of two or three times deserves attention.
Foamy urine. Fine foam that lingers rather than clearing suggests protein is escaping into the urine, which is one of the earliest measurable signs of filter damage.
Mild swelling. Ankles that leave a mark from your socks, or slight puffiness around the eyes in the morning.
Trouble concentrating. Waste products accumulating in the blood affect mental sharpness before they cause anything more dramatic.
Blood pressure that becomes harder to control. When a previously stable blood pressure starts needing more medication, the kidneys are worth checking.
Itching. Persistent, without a rash, and often worse at night.
None of these proves kidney disease. All of them, in someone with diabetes or high blood pressure, justify a test.
Advanced symptoms
When function drops substantially, the picture becomes unmistakable:
- Significant swelling in the legs, hands and face
- Nausea, vomiting and loss of appetite, sometimes with a metallic taste
- Shortness of breath from fluid in the lungs
- Muscle cramps, particularly at night, from mineral imbalances
- Very dry, itchy skin
- Marked reduction in urine output
- Difficulty sleeping
- Confusion in the most advanced stages
By this point the goal shifts from prevention to management, which is precisely the shift I want to help patients avoid.
The five stages
Staging is based on estimated glomerular filtration rate (eGFR), a calculation from your creatinine, age and sex that estimates how much filtering capacity remains.
Stage 1: eGFR 90 or above, with evidence of kidney damage such as protein in the urine. Function is normal. Symptoms are absent. This is the ideal moment to intervene.
Stage 2: eGFR 60 to 89, with damage present. Mild reduction. Still usually asymptomatic.
Stage 3: eGFR 30 to 59. Moderate reduction, often split into 3a and 3b. Some people begin noticing fatigue or swelling. Anemia and mineral problems start to appear. Most people are diagnosed here, and there is still a great deal that can be done.
Stage 4: eGFR 15 to 29. Severe reduction. Symptoms are usually present. This is when we begin discussing what treatment would look like if function continues to decline, because planning ahead produces far better outcomes than reacting.
Stage 5: eGFR below 15. Kidney failure. Dialysis or transplant is needed.
The number that matters most is not the stage itself but the trajectory. A stable eGFR of 45 is a very different situation from one that has fallen from 75 to 45 in two years.
Who should be screened
Annual testing is warranted if you have:
- Diabetes, the leading cause of kidney failure
- High blood pressure, the second leading cause
- Cardiovascular disease
- A family history of kidney disease
- Obesity
- Lupus or another autoimmune condition
- A history of acute kidney injury
- Regular use of anti inflammatory medication
- Age over 60
The two tests that find it in time
Kidney screening is neither complicated nor expensive. It is two tests.
Blood creatinine with eGFR. Tells you how much filtering capacity you currently have.
Urine albumin-to-creatinine ratio. Tells you whether the filters are leaking, and typically turns abnormal earlier than creatinine rises.
Both together give a far more complete picture than either alone. It is common to see normal creatinine with clearly abnormal albuminuria, which is early kidney disease that a creatinine only workup would miss entirely.
Your physician may add a urinalysis, an ultrasound or blood electrolytes depending on what those two show.
What protecting your kidneys actually involves
- Control blood pressure. The single highest impact action for most people.
- Control blood sugar if you have diabetes.
- Treat proteinuria, usually with an ACE inhibitor or ARB.
- Reduce dietary sodium, which makes blood pressure control achievable.
- Be careful with anti inflammatories. Occasional use is generally fine; regular use is not, particularly if you already have reduced function.
- Stay adequately hydrated, without extremes.
- Do not smoke.
- Keep a healthy weight and stay physically active.
- Review your medications periodically, including supplements.
Paying attention is the whole point
I want to close with the reason this article exists. The people who do best are not the ones with the mildest disease. They are the ones who found out early and acted.
Kidney disease at stage 1 or 2, treated properly, frequently never progresses to anything that affects daily life. The same disease found at stage 4 offers far fewer options. The difference between those two stories is usually a blood test and a urine test, done at the right time, in someone who had a risk factor and did not ignore it.
Talk to a nephrologist in Santo Domingo
I am Dr. Elizabeth Villanueva, a nephrologist and internist practicing in Santo Domingo, Dominican Republic. If you have diabetes, high blood pressure or a family history of kidney disease, or if a recent test showed reduced filtration or protein in your urine, bring your results to a consultation.
Understanding where your kidneys stand today is what makes it possible to protect them tomorrow.
Request an appointment or read more about how I work.