Casal's necklace' is seen in the following disease
The Casal necklace is an erythematous pigmented skin rash in the distribution of a broad collar (dermatomes C3 and C4). It is seen in patients with pellagra. It occurs as a result of niacin (vitamin B-3) deficiency. Pellagra is a disease characterised by diarrhoea, dermatitis and dementia. Ref : Biochemistry by U. Satyanarayana 3rd edition Pgno : 138-141
Beri-Beri
Scurvy
Pernicious anemia
Pellagra
vitamins