Everything about Scurvy totally explained
Scurvy (N.Lat. scorbutus) is a
deficiency disease that results from insufficient intake of
vitamin C, which is required for correct
collagen synthesis in humans. The scientific name of vitamin C, ascorbic acid, is derived from the Latin name of scurvy, scorbutus. Scurvy leads to the formation of
liver spots on the skin, spongy gums, and bleeding from all
mucous membranes. The spots are most abundant on the thighs and legs, and a person with the ailment looks pale, feels depressed, and is partially immobilized. In advanced scurvy there are open,
suppurating wounds and loss of
teeth.
Scurvy was at one time common among
sailors,
pirates and others aboard
ships at sea longer than perishable
fruits and
vegetables could be stored, and by
soldiers similarly separated from these foods for extended periods. It was described by
Hippocrates (c. 460 BC–c. 380 BC). Herbal cures for scurvy have been known in many native cultures since prehistory. In 1536, the French explorer
Jacques Cartier, exploring the
St. Lawrence River, used the local natives' knowledge to save his men who were dying of scurvy. He boiled the needles of the
arbor vitae tree (Eastern White Cedar) to make a tea that was later shown to contain 50 mg of vitamin C per 100 grams. Such treatments were not available aboard ship, where the disease was most common. It was a Scottish surgeon in the British
Royal Navy,
James Lind who first proved it could be treated with
citrus fruit in experiments he described in his
1753 book,
A Treatise of the Scurvy.
In infants, scurvy is sometimes referred to as
Barlow's disease, named after Sir
Thomas Barlow, a British
physician who described it. (N.B. Barlow's disease may also refer to
mitral valve prolapse.) Other eponyms include
Moeller's disease and
Cheadle's disease.
Symptoms
Prognosis
Untreated scurvy is invariably fatal. Since all that's required for a full recovery is the resumption of normal
vitamin C intake, death from scurvy is rare in modern times.
Pathophysiology
Normal collagen synthesis depends upon the
hydroxylation of
proline and
lysine residues in the endoplasmic reticulum, to form
hydroxyproline and
hydroxylysine, respectively. Prolyl and
lysyl hydroxylase, the enzymes that catalyze the hydroxylation, require ascorbic acid (vitamin C) to function correctly. With no ascorbic acid, the enzymes can't hydroxylate proline and lysine, and so normal collagen synthesis can't be performed.
History
Scurvy was probably first observed as a disease by
Hippocrates. In the
13th century the
Crusaders suffered from scurvy frequently. Scurvy was one of the limiting factors of marine travel, often killing large numbers of the passengers and crew on long-distance voyages. It even played a significant role in
World War I.
The British civilian medical profession of 1614 knew that it was the acidic principle of citrus fruit which was lacking, although they considered any acid acceptable when ascorbic acid (Vitamin C) was unavailable. In 1614
John Woodall (Surgeon General of the
East India Company) published "The Surgion's Mate" as a handbook for apprentice surgeons aboard the company's ships. In it he described scurvy as resulting from a dietary deficiency. His recommendation for its cure was fresh food or, if not available, oranges, lemons, limes and tamarinds, or as a last resort, Oil of Vitriol (
sulfuric acid).
In 1734, the
Leiden-based physician
Johann Bachstrom published a book on scurvy in which he stated that
"scurvy is solely owing to a total abstinence from fresh vegetable food, and greens; which is alone the primary cause of the disease." and urged the use of fresh fruit and vegetables as a cure. It wasn't until
1747 that
James Lind formally proved that scurvy could be treated and prevented by supplementing the diet with citrus fruit such as
lemons and
lime.
James Cook succeeded in circumnavigating the world (1768-71) in
HM Bark Endeavour without losing a single man to scurvy, but his suggested methods, including a diet of
sauerkraut and wort of malt, were of limited value. Sauerkraut was the only vegetable food that retained a reasonable amount of ascorbic acid in a pickled state, but it was boiled to reduce it for preservation and much of the Vitamin C content was lost. In Cook's time it was impractical to preserve citrus fruit for long sea voyages. More important was Cook's regime of shipboard cleanliness, enforced by strict discipline, as well as frequent replenishing of fresh food. The most effective regime implemented by Cook was his prohibition against the consumption of fat scrubbed from the ship's copper pans, then a common practice in the Navy. In contact with the hot copper, this fat acquired substances which possibly irritated the gut and prevented proper absorption of vitamins. The first major long distance expedition that experienced virtually no scurvy was that of
Alessandro Malaspina, 1789-1794. Malaspina's medical officer, Pedro González, was convinced that fresh oranges and lemons were essential for preventing scurvy. Only one outbreak occurred, during a 56-day trip across the open sea. Five sailors came down with symptoms, one seriously. After three days at Guam all five were healthy again. Spain's large empire and many ports of call made it easier to acquire fresh fruit. Despite advances, British sailors throughout the American Revolutionary period continued to suffer from scurvy, particularly in the Channel Fleet. The eradication of scurvy from the Royal Navy was finally due to the chairman of the Navy's
Sick and Hurt Board,
Gilbert Blane, who finally put Bachstrom and Lind's long-ignored prescription of fresh lemons to use during the
Napoleonic Wars. Other navies soon adopted this successful solution.
In
1927,
Hungarian biochemist Szent-Györgyi (who won the
1937 Nobel Prize for Medicine) isolated the compound "hexuronic acid" while working with
antioxidant compounds in the
adrenal cortex. It wasn't until
1932 that the connection between vitamin C and scurvy was established by
American researcher
Charles Glen King of the
University of Pittsburgh.
Modern incidence
Scurvy or subclinical scurvy is caused by the lack of vitamin C. In modern western society, scurvy is rarely present in adults, although infants and elderly people are affected. Vitamin C is destroyed by the process of
pasteurization, so babies fed with ordinary bottled milk sometimes suffer from scurvy if they're not provided with adequate vitamin supplements. Virtually all commercially available baby formulas contain added vitamin C for this reason, but heat and storage destroy vitamin C. Human
breast milk contains sufficient vitamin C, if the mother has an adequate intake.
Scurvy is one of the accompanying diseases of
malnutrition (other such micronutrient deficiencies are
beriberi or
pellagra) and thus is still widespread in areas of the world depending on external food aid. Though rare, there are also documented cases of scurvy due to poor dietary choices by people living in industrialized nations.
Prevention
Scurvy can be prevented by a diet that includes certain citrus fruits such as
oranges or
lemons. Other sources rich in vitamin C are fruits such as
blackcurrants,
guava,
kiwifruit,
papaya,
tomatoes and
strawberries. It can also be found in some vegetables, such as
carrots,
bell peppers,
broccoli,
potatoes,
cabbage,
spinach and
paprika, as well as some
pickled vegetables. Though redundant in the presence of a balanced diet, various nutritional supplements are available that provide ascorbic acid well in excess of that required to prevent scurvy, and even some
candies contain vitamin C.
Scurvy in animals
Like humans, other
primates and
guinea pigs lack the gene that makes vitamin C and thus require vitamin C in the diet to prevent the development of scurvy. Scurvy is sometimes seen in pet guinea pigs that are fed an inadequate diet. To prevent scurvy in guinea pigs, they should be fed guinea pig food such as guinea pig pellets, which must be supplemented with fresh fruit and vegetables or vitamin C drops as the vitamin C in the pellets degrades very quickly (50% within six weeks of manufacture). It isn't recommended that any supplement or medication be given to a guinea pig via a water bottle as it may impact their water consumption.
Further Information
Get more info on 'Scurvy'.
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