Excerpt from Scurvy

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Background

Scurvy, a state of dietary deficiency of vitamin C (ascorbic acid) is an ancient disease. Egyptians recorded its symptoms as early as 1550 BC. Scurvy was the scourge of the sea explorers of the Renaissance era (16th-18th centuries). In 1746, James Lind, a British naval surgeon, established the fact that oranges and lemons were effective in curing scurvy. The incidence of scurvy among the British sailors sharply declined upon routine provision of lemon juice on board. During the 19th century, people who experienced the Great Potato Famine, armies of the Crimean War and American Civil War, Arctic explorers, and California Gold Rush communities were prominent victims of "land" scurvy.

Francis Glisson is credited with the earliest description of infantile scurvy. In 1650, Glisson observed the co-occurrence of scurvy in infants with rickets. After Glisson's description, infantile scurvy was not reported for another 200 years. By the end of the 19th century, infantile scurvy was readily recognized and frequently observed in Britain and the United States. The increased incidence of infantile scurvy during this era was attributed to the consumption of heated milk and proprietary foods deficient in vitamin C.

In 1912, Holst and Frolisch induced and cured scurvy in guinea pigs through dietary modification. Utilization of an animal model for induction and treatment of scurvy was a major advance. Soon, human experiments followed. In 1914, Alfred Hess, a pediatrician practicing at the Hebrew Asylum in New York, observed an increase in scurvy among the infants at the asylum. This increase in scurvy coincided with the introduction of pasteurized milk and exclusion of orange juice from the infants' diet.

Modifying the infants' diet, with the provision of raw milk or orange juice or potatoes, Hess reversed the scurvy and effected a cure. Hess had demonstrated that pasteurization results in the loss of vitamin C. He recommended the provision of fresh fruit or vegetable juice for the prevention of scurvy in infants fed on heated formulas. This practice of supplementing the diet of infants receiving heated formulas with fresh fruit or vegetable juices eventually led to the eradication of infantile scurvy in the United States.

The human body lacks the ability to synthesize and make vitamin C and therefore depends on exogenous dietary sources to meet vitamin C needs. Consumption of fruits and vegetables or diets fortified with vitamin C are essential to avoid ascorbic acid deficiency. Even though scurvy is uncommon, it still occurs and can affect adults and children who have chronic dietary vitamin C deficiency.

Pathophysiology

Vitamin C is functionally most relevant for collagen synthesis, and a vitamin C deficiency results in impaired collagen synthesis. The typical pathologic manifestations of vitamin C deficiency are noted in collagen-containing tissues and in organs and tissues such as skin, cartilage, dentine, osteoid, and capillary blood vessels. Pathologic changes are a function of the rate of growth of the affected tissues; hence, the bone changes are often observed only in infants during periods of rapid bone growth.

Defective collagen synthesis leads to defective dentine formation, hemorrhaging into the gums, and loss of teeth. Hemorrhaging is a hallmark feature of scurvy and can occur in any organ. Hair follicles are one of the common sites of cutaneous bleeding.

Bone involvement is typical for infantile scurvy. The bony changes occur at the junction between the end of the diaphysis and growth cartilage. Osteoblasts fail to form osteoid (bone matrix), resulting in cessation of endochondral bone formation. Calcification of the growth cartilage at the end of the long bones continues, leading to the thickening of the growth plate. The typical invasion of the growth cartilage by the capillaries does not occur. Preexisting bone becomes brittle and undergoes resorption at a normal rate, resulting in microscopic fractures of the spicules between the shaft and calcified cartilage. With these fractures, the periosteum becomes loosened, resulting in the classic subperiosteal hemorrhage at the ends of the long bones. Intra-articular hemorrhage is rare because the periosteal attachment to the growth plate is very firm.

Besides being essential for collagen synthesis, ascorbic acid is important for biosynthesis of carnitine and neurotransmitters and in hematopoiesis by promoting iron absorption.

Frequency

United States

Currently, scurvy occurs very rarely in the United States. Patients who are elderly or alcoholic and who subsist on diets devoid of fresh fruits and vegetables are vulnerable. Infants and children on restrictive diets because of medical, economic, or social reasons are at risk for scurvy. Occurrence of scurvy is uncommon in those younger than 7 months.

International

International occurrence is unknown. A case series from Thailand reviewed 28 cases of scurvy in infants and children (10 mo to 9 y and 7 mo; median age, 29 mo) hospitalized over a 7-year period (1995-2002) and noted prolonged consumption of heated milk (ultra-high temperature [UHT] milk) and inadequate intake of vegetables and fruits as the risk factors for the development of scurvy. Epidemic scurvy has been reported among refugee populations.

Mortality/Morbidity

• Sudden death due to cardiac failure is reported in infants and adults.
• Predominant morbidity is a result of hemorrhage into various tissues. Subperiosteal hemorrhage in the tibia and femur causes excruciating pain.

Race

No racial predilection exists.

Sex

No sexual preponderance exists.

Age

Scurvy can occur at any age. Most cases of infantile scurvy occur when the infant is aged 6-24 months. Scurvy is uncommon in the neonatal period.

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