uremic frost

{{Short description|Crystallized urea deposits on skin}}

File:Uremic frost on forehead and scalp of young Afro-Caribbean male.jpg

Uremic frost is a colloquial description for crystallized urea deposits that can be found on the skin of those affected by chronic kidney disease (CKD) and uremia.{{cite book|author=Dennis, Mark|author2=Bowen, William Talbot|author3=Cho, Lucy|chapter=Uraemic frost|chapter-url=https://books.google.com/books?id=FIV-NYPRCzEC&pg=PA556|title=Mechanisms of Clinical Signs|year=2012|publisher=Elsevier|page=556|isbn=978-0729540759|postscript=; pbk}} It was first described in 1865 by Harald Hirschsprung (1830-1916), a Danish pediatrician.{{cite journal |pmc=4377803 |date=2014 |last1=Mathur |first1=M. |last2=d'Souza |first2=A. V. |last3=Malhotra |first3=V. |last4=Agarwal |first4=D. |last5=Beniwal |first5=P. |title=Uremic frost |journal=Clinical Kidney Journal |volume=7 |issue=4 |pages=418–419 |doi=10.1093/ckj/sfu057 |pmid=25852925 }}

The condition arises when high blood urea levels lead to high secretion of urea by sweat glands as a component of sweat. As water evaporates off the skin, it results in crystallization of the remaining urea which appear as white salts over the skin.{{cite journal |url=https://doi.org/10.1111/ijd.12963 |doi=10.1111/ijd.12963 |title=Uremic frost: A harbinger of impending renal failure |date=2016 |last1=Saardi |first1=Karl M. |last2=Schwartz |first2=Robert A. |journal=International Journal of Dermatology |volume=55 |issue=1 |pages=17–20 |pmid=26475684 |url-access=subscription }} This condition is more common in severe, untreated uremia and is associated with serum blood urea nitrogen (BUN) levels above 200{{clarify|date=March 2025}}. It is becoming rare in people with chronic kidney disease managed on long-term hemodialysis, with estimated prevalence between 0.8 and 3%.{{cite web|last1=Lynde|first1=Carrie|last2=Kraft|first2=John|title=Skin manifestations of kidney disease|url=http://www.parkhurstexchange.com/clinical-reviews/ct_02_vol15|website=Parkhurst Exchange|access-date=2 October 2014}}{{cite journal |vauthors=Falodun O, Ogunbiyi A, Salako B, George AK |title=Skin changes in patients with chronic renal failure |journal=Saudi J Kidney Dis Transpl |volume=22 |issue=2 |pages=268–72 | date=March 2011 |pmid=21422624 }}{{cite journal |vauthors=Udayakumar P, Balasubramanian S, Ramalingam KS, Lakshmi C, Srinivas CR, Mathew AC |title=Cutaneous manifestations in patients with chronic renal failure on hemodialysis |journal=Indian J Dermatol Venereol Leprol |volume=72 |issue=2 |pages=119–25 |year=2006 |pmid=16707817 |doi= 10.4103/0378-6323.25636|doi-access=free |hdl=1807/5641 |hdl-access=free }}