S: WHO – http://www.who.int/nutrition/publications/emergencies/WHO_NHD_00.10/en/ (last access: 4 September 2014); https://www.nlm.nih.gov/medlineplus/ency/article/000342.htm (last access: 4 September 2014); http://www.medicinenet.com/script/main/art.asp?articlekey=4821 (last access: 4 September 2014).
N: 1. chronic disease caused by dietary deficiency and characterized by skin eruptions, 1811, a hybrid formed from Latin pellis “skin” (see film (n.)) + Greek agra “a catching, seizure,” related to agrein “to take, seize.” But OED suggests it might be originally Italian pelle agra “rough skin.” Related: Pellagrous.
2. Pellagra is characterized by skin lesions and by gastrointestinal and neurological disturbances; the so-called classical three types of pellagra are dermatitis, diarrhea, and dementia.
3. Skin lesions result from an abnormal sensitization of the skin to sunlight and tend to occur symmetrically on the exposed surfaces of the arms, legs, and neck. They may look at first like a severe sunburn, later becoming reddish brown, rough, and scaly. Gastrointestinal symptoms usually consist of diarrhea, with an accompanying inflammation of the mouth and the tongue and fissuring and dry scaling of the lips and corners of the mouth. Neurological signs appear later in most cases, when the skin and alimentary manifestations are prominent.
4. Cultural Interrelation: We can mention the movie The Southerner (1945) by Jean Renoir (1894-1979).
S: 1. OED – http://www.etymonline.com/index.php?allowed_in_frame=0&search=pellagra&searchmode=none (last access: 4 September 2014). 2 & 3. EncBrit – http://global.britannica.com/science/pellagra (last access: 4 September 2014). 4. http://www.filmsufi.com/2010/04/southerner-jean-renoir-1945.html (last access: 6 June 2016).