scurvy

scurvy
Name	Scurvy
Caption	Illustration of gingivitis and ecchymosis, common signs.
Field	Endocrinology, Nutrition
Symptoms	Fatigue, gingival disease, petechiae, poor wound healing
Complications	Hemorrhage, jaundice, neuropathy, death
Onset	1–3 months of severe deficiency
Causes	Vitamin C deficiency
Risks	Malnutrition, alcoholism, eating disorders, dialysis
Diagnosis	Based on symptoms, confirmed by blood test
Prevention	Diet containing citrus fruit, supplementation
Treatment	Vitamin C supplementation
Medication	Ascorbic acid
Prognosis	Excellent with treatment
Frequency	Rare in developed nations

scurvy. Scurvy is a disease resulting from a severe deficiency of vitamin C, an essential nutrient for humans. This condition impairs the synthesis of collagen, leading to the breakdown of various bodily tissues and causing a wide array of symptoms. Historically associated with long sea voyages, its prevention through dietary sources like citrus fruit represents a major milestone in nutritional science.

Signs and symptoms

Early manifestations often include malaise, lethargy, and psychosomatic complaints. As it progresses, classic signs emerge, such as gingivitis with bleeding gums, loosening of teeth, and perifollicular hemorrhage. Skin symptoms include petechiae, ecchymosis, and hyperkeratosis. Musculoskeletal problems involve arthralgia, myalgia, and hemarthrosis. Severe cases can lead to jaundice, edema, fever, neuropathy, convulsions, and ultimately death from hemorrhage or infection.

Causes

The sole cause is a prolonged, severe deficiency of vitamin C, also known as ascorbic acid. Humans cannot synthesize this vitamin due to a mutation in the GULO gene, making dietary intake essential. High-risk groups include individuals with malnutrition, alcoholism, or eating disorders like anorexia nervosa. Patients undergoing dialysis, those with malabsorption syndromes such as Crohn's disease, and people consuming restrictive diets, including some followers of fad diets, are also vulnerable. Historically, populations without access to fresh produce, like sailors on ships of the Royal Navy or soldiers during the Siege of Jerusalem, were commonly affected.

Pathophysiology

Vitamin C is a critical cofactor for enzymes involved in collagen synthesis, including prolyl hydroxylase and lysyl hydroxylase. Without it, hydroxyproline and hydroxylysine are not formed, leading to defective collagen fibrils. This weakens connective tissue in blood vessels, skin, and gums, causing fragility and hemorrhage. The vitamin also acts as an antioxidant, protects against oxidative stress, and aids in carnitine biosynthesis and neurotransmitter metabolism. Its deficiency disrupts iron absorption and bone formation, contributing to anemia and pain.

Diagnosis

Diagnosis is primarily clinical, based on a history of inadequate intake and the characteristic signs. Blood tests can confirm low levels of vitamin C in plasma or leukocytes. Findings may include anemia and elevated serum ferritin. Radiography might reveal scorbutic rosary at the costochondral junction and subperiosteal hemorrhage in children, a condition historically described by Thomas Barlow. Differential diagnosis includes bleeding disorders like hemophilia, vasculitis such as Henoch–Schönlein purpura, and other nutritional deficiencies like pellagra.

Prevention

Prevention is achieved by consuming sufficient vitamin C daily. Excellent dietary sources include citrus fruit like oranges and lemons, kiwifruit, strawberries, bell peppers, broccoli, and potatoes. Historical implementation of preventative measures, such as the issuance of lime juice by the Royal Navy following the experiments of James Lind, drastically reduced cases. Modern guidelines, like those from the National Institutes of Health, recommend daily intake through diet or supplementation, especially for at-risk individuals.

Treatment

Treatment involves the oral or intravenous administration of vitamin C (ascorbic acid). Symptoms often improve within 24 hours, with bleeding and pain resolving in days. Complete recovery, including healing of gingival disease and wounds, typically takes weeks. Standard therapeutic doses are significantly higher than the Recommended Dietary Allowance. In severe cases with anemia, iron supplementation may also be required. The efficacy of citrus fruit extract as a cure was famously demonstrated by James Lind aboard HMS Salisbury.

History

Descriptions of scurvy appear in ancient texts, including those from Hippocrates and in accounts of the Crusades. It became a major scourge during the Age of Discovery, devastating crews on voyages by explorers like Vasco da Gama and Ferdinand Magellan. The breakthrough came in 1747 when James Lind conducted one of the first controlled clinical trials, proving the curative power of citrus fruit. Implementation was slow until advocated by figures like Gilbert Blane, leading the Royal Navy to mandate lime juice rations, earning British sailors the nickname "limey." The isolation of ascorbic acid by Albert Szent-Györgyi and its synthesis by Walter Norman Haworth in the 1930s finalized the scientific understanding of the disease.

Category:Diseases and disorders Category:Nutritional deficiencies