Sprue, or psilosis, is a disease of uncertain origin, characterized by diarrhoea with the passage of large, fatty stools, anaemia, sore tongue and los of weight. The general consensus of opinion on its cause is that it is a metabolic disorder associated with an inability to absorb fats from the intestine. This explains the bulky, frothy stools due to an excess of fat. Subsequently there is interference with the absorption of carbohydrate, vitamins and minerals. This causes the other symptoms. In untreated cases the patient steadily loses weight and becomes emaciated. Death is usually due to exhaustion and/or infection.
The name sprue was first given to the condition in 1879 by Sir Patrick Manson, and it was then considered to be a disease of tropical climates. Subsequent investigations have shown that a similar condition occurs in individuals who have never been in the tropics. This is known as 'non-tropical sprue'.
Tropical sprue is found chiefly in India, Burma, Malaysia and China. It also occurs in the southern states of USA, the West Indies and South America. It is more common in Europeans than in natives, and is more common in women than in men. As a rule it occurs after long residence in the tropic, and the onset is usually after the rains. There is quite often a preceding history of dysentery.