Recognizing the Symptoms of Kidney Failure

The kidneys are powerful organs; they filter blood, remove waste, produce hormones, and eliminate extra fluid from the body. Kidney failure happens when the kidneys lose the ability to function normally. Symptoms include a change in urine output, shortness of breath, confusion, insomnia, swelling, nausea, and fatigue. However, not everyone with failing kidneys shows symptoms.

For people with chronic kidney disease (CKD), the kidneys typically lose functionality gradually and fail in the later stages. People who have a different medical condition may experience acute kidney injury (AKI), a condition in which the kidneys fail suddenly — often in a matter of hours or days. While there is no cure for kidney failure due to CKD, many people manage it with dialysis or a kidney transplant. AKI, on the other hand, may be reversible.

Failing kidneys can make it difficult to fall and stay asleep. In fact, studies show that 50% to 75% of people with kidney failure also have insomnia. When kidneys stop working, waste products, toxins, and fluid start to accumulate. This can lead to other complications that make it difficult to sleep, including restless leg syndrome, sleep apnea, anxiety, uremia, and periodic limb movement. Insomnia may also show up in the early stages of CKD.

Fatigue is one of the most common symptoms of kidney failure. As toxins start to build up in the bloodstream, they can create a noticeable drop in energy. Other conditions associated with kidney failure, including anemia, insomnia, loss of appetite, and muscle cramps, can also make people feel more exhausted than usual. Addressing the underlying cause of fatigue can help resolve the problem.

Normally functioning kidneys create urine from excess fluid and waste products. When the kidneys are impaired, they may cause changes in urination. Some people begin to urinate less or more frequently. Others notice a dramatic change in color — failing kidneys can send blood or protein into the urine, turning it dark red, purple, or brown. Protein in urine can also give the liquid a foamy consistency.

People with kidney failure may experience persistent itchy skin. For some people, itching is simply a side effect of dry skin. People in the later stages of CKD may develop uremic pruritus or itching caused by an accumulation of toxins. The sensation can happen all over the body or be limited to one spot. It's unpredictable, often appearing and disappearing for varying amounts of time. If the itching is bad enough, it can disrupt sleep and impact the overall quality of life.

As kidneys fail, they become less effective at eliminating fluid. Instead of exiting the body as urine, that fluid begins to build up in other parts of the body — usually, the ankles, legs, and abdomen. The fluid that accumulates in the lungs can lead to pulmonary edema. Sodium buildup stemming from kidney failure can make the problem worse, causing extra water retention and swelling.

Some people find that diuretics help eliminate excess fluid. Doctors may also advise people with kidney failure to avoid sodium, change how much they drink, or keep their blood pressure in check.

Kidney failure often results in shortness of breath, but the causes vary. Anemia is a common culprit; it reduces oxygen levels, so even mild exercise makes it difficult to breathe. In people with pulmonary edema, shortness of breath increases as fluid fills the air sacs in the lungs. The same thing can happen with heart failure that results from CKD and kidney failure. As the heart pumps less effectively, fluid accumulates in the lungs.

In the later stages of CKD, people may develop pericarditis — inflammation of the pericardium, the fluid-filled sac that surrounds the heart. Swelling in the sac causes sharp or dull chest pain that gets worse when the person lies down. Sometimes, it's accompanied by a grating sound called a pericardial rub, which happens when the heart makes contact with the inflamed pericardium. Shortness of breath related to fluid buildup can also cause discomfort in the chest.

Chest pain is a serious symptom, even when it's not connected to kidney failure. People should seek medical attention immediately to find the cause and get treatment if necessary.

Toxin accumulation often suppresses the appetite, leaving people with kidney failure unable or unwilling to eat. Some people find that their tastes change as CKD progresses. They might suddenly dislike their favorite foods or struggle to find meals that sound appealing. Nausea can make matters worse.

A poor appetite makes it difficult to get adequate nutrition — an important part of living with kidney failure. Many people find it helpful to work with a dietitian to select foods that are both palatable and nourishing.

When the kidneys stop ridding the body of waste, toxins start to impact other parts of the body. A buildup in the bowel or stomach tissues can cause extreme bouts of nausea. People with this symptom may find themselves struggling to eat or smell certain odors without vomiting. Nausea often gets more intense as CKD progresses, but may be alleviated with treatments such as dialysis.

Functioning kidneys produce a hormone called erythropoietin (EPO), which stimulates the production of red blood cells. Kidney failure reduces EPO production and red blood cell levels. This decrease can cause anemia, a condition that lowers the oxygen in the bloodstream and leaves people feeling unusually weak and fatigued. They may also find it difficult to breathe after exerting themselves. About 12% of people with CKD develop anemia.

Two of the problems linked to kidney failure — low blood oxygen levels and reduced blood flow due to heart failure — can affect the brain, causing memory loss and difficulty concentrating. Insomnia can also be a contributing factor; sleep deprivation prevents normal memory function. The problem tends to get worse as waste products build up in the bloodstream, creating chronic inflammation and throwing off the balance of free radicals and antioxidants. Research shows evidence of cognitive decline in up to 70% of people who are on dialysis for kidney failure in late-stage CKD.

Impaired kidneys aren't always able to remove excess phosphate from the body. As phosphate levels rise, calcium levels fall. Since these electrolytes regulate muscle contractions, an imbalance due to kidney failure can cause sudden, involuntary muscle cramps. People who drink a large volume of fluid between dialysis sessions may also experience cramping. Treatments may include massage, fluid reduction, and stretching.

It's critical to seek medical attention immediately for significant symptoms of kidney failure, including confusion, chest pain, and shortness of breath. These signs may also indicate a heart attack or another serious medical issue.

Not everyone exhibits signs of kidney failure — and in many cases, symptoms do not show up until the advanced stages of CKD. Anyone who notices symptoms, even mild ones, should check in with a doctor. Early detection makes it easier to slow the progression of CKD and reduce the risk of kidney failure in the future.

Dialysis, which uses a machine to filter waste and excess fluid from the blood, is a common treatment for kidney failure. It often requires multiple visits per week, each lasting about 3 to 4 hours. Doctors may also recommend lifestyle changes, including exercise, dietary modifications, and proper management of other health conditions. People who follow medical advice can live with kidney failure for many years. Since there is no cure for kidney failure associated with late-stage CKD, however, most people need a kidney transplant to regain normal or near-normal function.

Treatment may be different for people whose kidneys are failing due to acute kidney injury (AKI). Doctors may use dialysis and prescribe medication to balance fluid levels and control electrolytes while they resolve the underlying problem. With quick intervention, it's possible for people with AKI to regain partial or full kidney function.

Prompt medical attention is critical for people with kidney failure, whether it's due to chronic kidney disease or acute kidney injury. By going to the doctor for regular check-ups, paying attention to symptoms, and communicating openly with healthcare providers, it's possible to spot the signs of kidney failure early and slow its progression.