Chronic Kidney Disease-Associated Pruritus
CKD-aP, Uremic pruritus, End-stage renal disease-associated chronic itch (ESRDCI)
Chronic kidney disease-associated pruritus is a distressing condition that affects up to 70% of people on dialysis and many others with advanced kidney disease. This persistent itching, often described as “an itch you just can’t get to,” can severely impact sleep, mood, and quality of life, yet it remains frequently overlooked and undertreated.
Table of contents
- What Is Chronic Kidney Disease-Associated Pruritus?
- How Common Is This Condition?
- What Does the Itching Feel Like?
- What Causes This Condition?
- How Is It Diagnosed?
- Impact on Daily Life
- Self-Care Strategies
- Medical Treatment Options
What Is Chronic Kidney Disease-Associated Pruritus?
Chronic kidney disease-associated pruritus, also called CKD-aP or uremic pruritus, is persistent itching experienced by people with chronic kidney disease and end-stage kidney disease. This condition is defined as moderate to severe itching that is directly related to kidney disease, without the presence of any other condition such as liver or skin disease that includes itching.[1][2]
The term “pruritus” is the medical word for itching. Unlike other forms of itching, CKD-aP is characterized by itching that is not caused by a primary skin problem or rash. The itching occurs daily or nearly daily and there is typically no visible skin change that explains why the itching happens.[2][4]
The condition is often a distressing and overlooked problem found primarily in individuals with end-stage kidney disease, especially those on hemodialysis. It can be either localized to specific body parts or generalized across large areas of the body.[3]
How Common Is This Condition?
Chronic kidney disease-associated pruritus is remarkably common among people with kidney disease. It is believed to affect approximately 30 to 70% of kidney patients.[3][10]
More than 40% of people receiving hemodialysis suffer from chronic itching, with about half experiencing generalized itching throughout their body.[2] Up to 70% of people who receive hemodialysis experience some degree of itching.[5]
The condition also affects people with chronic kidney disease who are not yet on dialysis. Around 25% of people with chronic kidney disease who aren’t on dialysis have uremic pruritus.[5] Studies show that itching occurs in patients with stages 3 to 5 chronic kidney disease who are not on dialysis, with increasing prevalence as kidney function worsens, age increases, and medical complications develop.[9]
People on dialysis, whether hemodialysis or peritoneal dialysis, are more likely to experience this condition than those not on dialysis.[5] The condition affects nearly all patients with advanced kidney disease at some point in their kidney journey.[4]
What Does the Itching Feel Like?
The itching associated with chronic kidney disease-associated pruritus can vary considerably from person to person. It can range from being mild and only happening occasionally, to severe and constant in some patients.[4]
The itching can have several characteristics. It can come and go, last throughout the day, or keep you up at night. It may feel like it’s all over your body or affect specific body parts. The itching can get worse when your skin is dry and can significantly affect your mental health and quality of life.[5]
Many people with this condition itch all over or on large areas of their body. The back, face, and shunt arm (where dialysis is received) are the most common specific places where itching occurs.[5] The condition may also impact various parts of a kidney patient’s body, such as the face, back, or arm.[3]
The severity of the itching may vary over time from mild to moderate to severe, and the itch may occur randomly or frequently. It may also occur anytime in relation to dialysis—before, during, or after treatment.[3]
Patients often describe this condition as “an itch you just can’t get to.”[3] Some kidney patients with advanced kidney disease and those on hemodialysis have reported that the itch comes and goes periodically and varies in severity, but many more report that the itch is constant.[3][10]
What Causes This Condition?
The exact cause of chronic kidney disease-associated pruritus is not fully known. Experts aren’t completely sure why people with chronic kidney disease and end-stage kidney disease experience itching, though several factors are believed to contribute.[5]
It is generally felt that the itching is caused by a combination of several factors. These include inflammation in the skin, toxins building up that are usually cleared by the kidneys, and an imbalance in the body’s nerve receptors.[4]
Most commonly, CKD-aP is attributed to toxin build-up, peripheral neuropathy (nerve damage), immune system dysregulation, or opioid dysregulation.[3][10]
Several specific mechanisms may explain the condition. Uremic toxins may play a role—when your kidneys aren’t working properly, harmful substances can build up in the blood, a condition called uremia. These toxins might contribute to making you itch.[5]
Another factor is immune system imbalance. Chronic kidney disease can change how well your immune system works. Imbalances and increased inflammation might trigger itching.[5]
Neuropathy, a condition where nerves aren’t sending or receiving signals correctly, may also contribute. Chemical imbalances in your body can lead to neuropathy, and your body might interpret these faulty nerve signals as itching.[5]
Some medications can cause itching as well. People with chronic kidney disease or end-stage kidney disease may take medications that contribute to itching, such as morphine-based painkillers.[4][5]
Skin dryness is very common in people with kidney disease and is associated with an increased risk of itching.[4] Substances such as histamine, parathyroid hormone, magnesium, and calcium have also been associated with the development of this condition. Newer studies are evaluating opioid-receptor abnormalities and microinflammation as potential causes.[2]
How Is It Diagnosed?
Before diagnosing chronic kidney disease-associated pruritus, it is important to rule out other causes of itching. Treatment of itching should be aimed at the actual cause, and sometimes patients have causes of itching that aren’t related to their kidney disease.[4]
Other conditions that cause itching, such as eczema, liver disease, atopy (allergic conditions), thyroid diseases, psoriasis, and some infections like scabies, should be excluded before diagnosing uremic pruritus.[2][4]
If you have chronic kidney disease or end-stage kidney disease and are experiencing itching, your healthcare provider will first look for other causes. They’ll check your skin for a rash or other changes. They might order blood tests. They’ll diagnose you with uremic pruritus if they rule out other causes.[5]
CKD-aP can be difficult to diagnose for several reasons. The severity may vary over time from mild to moderate to severe, and the itch may occur randomly or frequently. Further complicating the diagnosis is the fact that no visual presentation on the skin may occur, although you may see marks or lesions from persistent scratching.[3]
CKD-aP does not generally cause a rash, so you should see your doctor if you notice visible changes in your skin. In later stages, prolonged scratching does lead to changes in the skin, called excoriations and nodular prurigo in severe cases.[4]
Due to all these factors, best practice is for physicians to consider any itching in dialysis patients as being related to CKD-aP unless there is a clear alternative explanation.[3]
Impact on Daily Life
Chronic kidney disease-associated pruritus significantly impacts patients’ quality of life. The condition affects sleep and leads to poor clinical outcomes and poor adherence to treatments.[2]
The condition has been associated with poor quality of life, poor sleep, and depression.[3] In fact, itching can disrupt your sleep and mood in severe cases, with a negative impact on your quality of life.[4]
The condition has also been associated with increased hospitalizations and death in hemodialysis patients. This is due to the increased risk of inflammation and infections caused by an individual’s continual scratching of the skin in an attempt to satisfy the itch, which can lead to lesions or broken and damaged skin.[3][10]
Scratching, however tempting, will make the problem of itching worse. This is because scratching sets off more inflammation in the skin. It is really important not to scratch, if you can.[4]
Self-Care Strategies
There are several things you can do yourself to help manage skin itching associated with chronic kidney disease-associated pruritus.[4]
Keep your fingernails short to avoid scratching and traumatizing the skin. This simple step can help prevent damage from unintentional scratching.[4]
Avoid wearing irritating fabrics such as wool. Stick to light, cotton clothing if you can. Comfortable, breathable fabrics are less likely to irritate your skin.[4]
Keep the skin cool and use lukewarm water in the bath or shower. Hot water can dry out your skin and make itching worse.[4]
Try to avoid using soap or harsh skin cleansers as they strip the skin of its natural oils. Use soap substitutes instead. These gentler alternatives help maintain your skin’s moisture barrier.[4]
Try to avoid using perfumed or fragranced products on your skin, as these can be irritating.[4]
Medical Treatment Options
There is no single treatment for uremic pruritus that works for everyone. Management of this condition involves a stepwise approach, starting with topical treatments and advancing to medications and other therapies as needed.[2][5]
Topical treatments include skin creams and emollients. These moisturizers help keep the skin hydrated and can reduce itching, especially since dry skin is common in people with kidney disease.[2][4]
Your healthcare provider may be able to modify your dialysis treatment to help relieve itching. Adjusting dialysis parameters is one option that may provide relief.[5]
Phototherapy is a form of therapy that uses light to treat skin conditions. Some types of phototherapy have been shown effective at reducing uremic pruritus.[2][5]
Certain medications that providers use to calm nerve pain help some people with itching. These include gabapentin and pregabalin, medications commonly used for neuropathic pain that can also reduce itching signals.[2][5]
Kappa-opioid agonists are medications that relieve itching by reducing the signals to your nerves that make you itch. These include difelikefalin and nalbuphine.[5] In 2021, the Food and Drug Administration approved a therapeutic for CKD-aP, a breakthrough, first-in-class therapy for this condition administered to dialysis patients at the end of their dialysis sessions. Generically known as Difelikefalin or KORSUVA Injection, this prescription medicine is used to treat the symptoms of this condition.[3][10]
Unfortunately, there has been frustratingly little innovation in the treatment of many chronic kidney disease side effects until recently. Treatments commonly prescribed for CKD-aP in the past, such as antihistamines and phosphorus binders, as well as a variety of lotions, have had very little to no effect on this condition.[3][10]
While not a treatment specifically for uremic pruritus, some people with chronic kidney disease receive a kidney transplant. A successful kidney transplant can provide relief from CKD-aP.[2] In one study, itching went away completely in nearly 3 out of 4 people who received a transplant.[5] Kidney patients who have been transplanted have reported that only then did the itch go away.[3][10]