Uremic pruritus is caused by chronic renal failure

Chronic renal failure

Chronic kidney disease , also known as chronic renal disease, is a progressive loss in renal function over a period of months or years. The symptoms of worsening kidney function are unspecific, and might include feeling generally unwell and experiencing a reduced appetite...

 and is the most common internal systemic cause of pruritus.

Pathogenesis of Uremic Pruritus

The cause of uremic pruritus is not fully clarified. Oveactivity of type 1 T helper cells (TH1) has been demonstrated in uremic pruritus. Furthermore, serum levels of interleukin-2, a cytokine produced by TH1 cells, have been demonstrated to be higher in dialysis patients with itch compared to dialysis patients without itch. This cytokine has a well-documented role in induction of pruritus.
Other proposed contributors to the pathogenesis of uremic pruritus include anemia or other manifestation of erythropoietin deficiency, inadequate dialysis, histamine release from skin mast cells, skin dryness, secondary hyperparathyroidism, hyperphosphatemia with increased
calcium phosphate deposition in the skin and alterations in the endogenous opioidergic system with overexpression of opioid μ-receptors.

Treatment of Uremic Pruritus

Therapeutic modalities and medications that target TH1 cells and inhibit production of interleukin-2 such as ultraviolet B phototherapy, tacrolimus and thalidomide have been demonstrated to be effective in treatment of uremic pruritus. Other therapeutic options include gabapentin, opoiod antagonists such as naltrexone, topical capsaicin, emollients, treating anemia of chronic kidney disease with erythropoietin, optimizing dialysis dose and antihistamines.