Early concepts of nutrition, digestion, diseases of the gastrointestinal tract and their treatment: from the Schola Medica Salernitana to Rokitansky and Virchow

The Schola Medica Salernitana and «The Salernitan Rule of Health» are monuments of medieval medicine and pharmacy. The Schola Medica Salernitana inherited the traditions of ancient medicine. «The Salernitan Rule of Health» examines the properties of various foods, fruits, and plants and their therapeutic effects. The work was written according to the custom of that time — in verse, because advice given in poetic form is better memorized. Gaspare Aselli (1581 — 1626) was a Milanese anatomist and surgeon. When his work on the lactiferous vessels of the intestine was published (1622), there was considerable controversy about how blood moved away from the heart as well as the mechanism by which fluid was transferred from the digestive tract to other organs. The Iatromathematical School claimed that physiological events should be seen as fixed sequences of physical laws. For example, the stomach was seen as a mechanical mill that turned the food into chyme. The Jesuit abbot Lazzaro Spallanzani (1729 — 1799) was a professor of physics and mathematics at the College of San Carlo in Modena. Throughout his life, he conducted a great deal of unique scientific research. He did important studies on gastric secretion in various animals and concluded that the digestion of food is a chemical process dependent on the digestive power of saliva and the dissolving properties of gastric juice. His definition that digestion is not putrefaction but an active process was a significant advance since his predecessors considered it a passive process. Recognition of the role of pathological anatomy in establishing the cause and nature of diseases was the next big step in the study of the gastrointestinal tract. The first definite information about the correlation between structural and functional disorders was provided by T. Bonet in his work «Sepulchretum» in 1679, later expanded and supplemented by G. Morgagni (1682 — 1771), J. Cruveilhier (1791 — 1873), and K. Rokitansky (1804 — 1878). Detailed descriptions of numerous cases (more than 30.000 from Rokitansky alone) provided information to understand the relationship between symptoms and autopsy data. In the 19th century, R. Virchow took his observations beyond the organ that was sick and came up with a cellular theory of pathological processes. 
 