The Casal collar or casal necklace is a

clinical sign Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showin ...

in which there is an

erythematous Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not assoc ...

pigmented skin rash in the distribution of a broad collar (

dermatome Dermatome may refer to: * Dermatome (anatomy), an area of skin that is supplied by a single pair of dorsal roots * Dermatome (embryology), the portion of the embryonic paraxial mesoderm, the somite, which gives rise to dermis * Dermatome (instrument ...

s C3 and C4). It is seen in patients with

pellagra Pellagra is a disease caused by a lack of the vitamin niacin (vitamin B3). Symptoms include inflamed skin, diarrhea, dementia, and sores in the mouth. Areas of the skin exposed to either sunlight or friction are typically affected first. Over t ...

,Barry G. Firkin, Judith A. Whitworth. ''Dictionary of Medical Eponyms.'' Informa Health Care, 2001, page 60. . as a result of

niacin Niacin, also known as nicotinic acid, is an organic compound and a form of vitamin B3, an essential human nutrient. It can be manufactured by plants and animals from the amino acid tryptophan. Niacin is obtained in the diet from a variet ...

(vitamin B₃) deficiency. The sign is named after

Gaspar Casal Gaspar Roque Francisco Narciso Casal Julian (31 December 1681–10 August 1759) was a Spanish physician remembered for describing the Casal collar in pellagra. Casal was born in Girona Catalonia, Spain to Federico Casal y Dajón and Magdalena Ju ...

, who first described pellagra.

References

External links

Image of Casal collar at phoenity.com
Accessed on 22 March 2009. Medical signs Dermatologic signs {{Med-sign-stub