| Casal collar | |
|---|---|
 | |
| A boy with casal collar caused bypellagra | |
| Specialty | Dermatology |
| Symptoms | Redness anddarkening around neck[1] |
| Causes | Pellagra[2] |
| Differential diagnosis | Seborrheic dermatitis[1] |
TheCasal collar orCasal necklace is amedical sign in which there is aredness anddarkening of the skin around the neck, seen in people withpellagra.[2] It becomes prominent following exposure to sun, and can be itchy with a burning feeling and pain.[1] It canblister and weep, and turn into thick dark skin, with a coppery hue.[1] If prolonged, the skin becomes thin, dry and smooth.[1]
The sign is caused by a lack of theniacin (vitamin B3).[1]Seborrheic dermatitis may appear similar.[1]
Casal collar is named afterGaspar Casal.[3]
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 | Thismedical sign article is astub. You can help Wikipedia byexpanding it. |