The final stage signs of pellagra disease are delirium, dementia, tremor, stupor and coma. In severe condition of pellagra disease symptoms like stiffness and inability to move arms and legs sets in.The patients also show signs like involuntary grasping and sucking movements, ataxia (lacking control over muscular movements) and fluid retention.nitial symptoms manifests as skin inflammations, lesions and rash with itching and burning sensation. Photodermatitis is one of the typical signs of the disease. The areas of skin exposed to sunlight become red and inflamed and show symptoms of sunburn.