A vitamin C deficiency characterized by tooth and gum bleeding and decay, hemorrhages, and increased susceptibility to infection.
Hypoascorbemia; Vitamin C Deficiency.
Not known. Less common (<6% in general population) in developed countries but increasing incidence in certain populations, including alcoholics, institutionalized elderly, and those with Postsurgical Malabsorption Syndrome.
Scurvy arises from the deficiency of ascorbic acid (vitamin C), which is often the result of prolonged lack of fresh fruit or vegetables in diet, historically common among the sailors on long sea voyages. Humans, unlike most other animals, do not possess the enzyme L-gulonolactone oxidase and thus are unable to synthesize ascorbic acid from the glucuronic acid or galactonic acid derived from glucose. Recommended daily allowance for ascorbic acid is 35 mg in infants, 45 to 50 mg for children, and 60 mg for adults. Ascorbic acid accelerates the hydroxylation reactions in a number of biosynthetic pathways. If ascorbic acid is replaced by other reductants, most of the enzymes in these pathways are still functional but not at optimal activity. It is best known for its essential role in the hydroxylation of proline and lysine to enable cross-linking and stabilization of collagen.
Clinical features and laboratory evaluation. Plasma ascorbate level is absent in clinical significant cases. Blood count usually shows anemia, which may be as a result of poor iron and/or folate absorption. Coagulation and biochemistry may also show abnormalities in association with poor nutritional status, including prolonged activated partial thromboplastin time (aPTT) and international normalized ratio (INR), low albumin, low protein, low cholesterol, and low sodium and potassium levels. Skin biopsy may show the characteristic hyperkeratosis of hair follicles and rule out vasculitis.
“The four Hs” are the classical manifestations of scurvy: hemorrhagic signs, hyperkeratosis of hair follicles, hypochondriasis, and hematologic abnormalities. The earliest sign is usually petechial hemorrhages, usually in hyperketotic areas such as the anterior forearms. Next to occur are ecchymoses and purpura, usually at sites of pressures, trauma, or irritation. Further depletion brings coiled (corkscrew) and fragmented hair with hyperkeratosis and hemorrhagic gingivitis. In severe cases, other symptoms include lower extremity edema, muscle tenderness, conjunctival and ocular hemorrhages, arthralgias, hemarthroses, gastrointestinal hemorrhage, Sicca (dry eye) Syndrome, poor wound healing, and peripheral neuropathy. Generalized symptoms are weakness, fatigue, and weight loss. Psychological symptoms include hypochondriasis, emotional lability, depression, and hysteria. Sudden death for unknown reasons has been reported. Treatment is simple, by replacing body stores of vitamin C by oral or intravenous route in severe case.
Precautions before anesthesia
Establish diagnosis from history, examination, and laboratory results. Ensure that treatment is adequate from clinical and biochemical status. Make sure that all ...