Persistent or severe itching often signals an underlying medical condition beyond common skin issues. When this symptom is caused by chronic kidney disease (CKD), it is known as uremic pruritus. This type of itching is most prevalent in individuals with end-stage kidney disease or those undergoing dialysis, though it can also manifest in earlier stages.

Unlike common itching, which may find relief from scratching or moisturizing, kidney-related pruritus originates internally rather than from the skin's surface. It significantly impacts a patient's sleep, mood, and daily life. Early detection and treatment can reduce discomfort and improve kidney health.

Causes of kidney-related skin itching

According to the National Center for Biotechnology Information (NCBI), several factors are associated with skin itching in individuals with kidney disease:

**Toxin accumulation:** When kidneys fail to filter waste from the blood, toxins build up in the body, irritating nerve endings and causing persistent itching. This itching often worsens at night or after dialysis.

**Inflammation:** Chronic inflammation associated with chronic kidney disease can alter the body's immune response, increasing sensitivity to itching. Inflammatory chemicals in the blood can heighten skin irritation and discomfort over time.

**Mineral imbalance:** Elevated levels of phosphorus, calcium, magnesium, or parathyroid hormones can affect skin and nerve health, leading to dry skin, rashes, and increased itching due to this mineral imbalance.

**Dry skin:** Reduced sweat gland function and the dialysis process can result in dry skin, making it prone to irritation, flaking, and cracking, which intensifies the sensation of itching.

**Neurological changes:** Chronic kidney disease can impact the nervous system, altering how the body perceives and responds to itch signals. This sometimes causes persistent itching even without external irritants.

Sensation and location of itching

Kidney-related itching varies in intensity and location. For some, it begins in one area, such as the back or arms, while for others, it spreads across the entire body. The itching often affects both sides, such as both arms or both legs, and can be more severe at night. Commonly affected areas include the back, shoulders, hands, legs, chest, abdomen, scalp, and face.

The itching sensation is not merely superficial; it can originate from beneath the skin. While scratching might offer temporary relief, it often exacerbates the irritation, leading to skin abrasions and infections.

Distinguishing kidney-related itching from common skin conditions

Common itching can stem from superficial issues such as dry skin, allergies, or insect bites. Kidney-related itching, however, is systemic, linked to internal chemical imbalances rather than external irritants.

Key distinctions of kidney-related skin itching include:

**Duration:** The itching can persist for months or even years.

**Widespread:** It affects broad areas rather than isolated spots.

**Unresponsive to scratching:** The sensation is only temporarily reduced or not relieved at all by scratching.

**Accompanied by kidney symptoms:** Fatigue, swelling, or changes in urination may also be present.

Bao Bao, *Times of India*