what vitamin deficiency causes  pellagra ( diarrhea, dermatitis, dementia, death)?
Pellagra. Are You Confident of the Diagnosis? Pellagra is classically described as the 4 D's in order of symptoms starting: diarrhea (watery, but may contain pus or blood), dermatitis, dementia, death. Three 3 P's also apply: photosensitive, painful, pruritic. Pellagra is the clinical manifestation of Vitamin B3 (niacin) deficiency.