'St Ignatius's itch' definitions:

Definition of 'St Ignatius's itch'

From: GCIDE

Pellagra \Pel"la*gra\ (p[e^]l"l[.a]*gr[.a]), n. [It. pelle skin + agro rough.] (Med.) An affection of the skin, characterized by redness, especially in exposed areas, scaling and shedding of the skin, and accompanied with severe gastrointestinal disturbance and nervous symptoms. It is due to a deficiency of niacin (vitamin B3; nicotinic acid) and protein in the diet, and may be caused by malnutrition, or, in some cases, by a heavy dependence on maize for food. It was at one time (ca. 1890) endemic in Northern Italy, and was called {Alpine scurvy}. It may also be caused by alcoholism or diease causing an impairment of nutrition. It is also called {St. Ignatius's itch}, maidism, mal de la rosa, mal rosso, and psychoneurosis maidica. A variety of pellagra seen in children is called infantile pellagra or kwashiorkor. --[Stedman] [1913 Webster +PJC]