Scurvy is a state of dietary deficiency of vitamin C (ascorbic acid). It is called Barlow’s disease in infants.
Scurvy is uncommon now but can affect adults and children with poor nutrition. Although scurvy can occur at any age, the incidence of scurvy peaks in children aged 6-12 months and elderly populations. Scurvy is uncommon in the neonatal period.
Role of Vitamin C in Body
The recommended daily allowance for vitamin C is 120 mg daily in adults. Infants require about 50 mg per day. A human body cannot synthesize vitamin C and therefore is dependent on dietary supply. Fruits and vegetables are particularly rich in vitamin C.
The total body pool of vitamin C is approximately 1500 mg. The absorbed vitamin is in the highest concentrations in glandular tissue. Muscles have its lowest concentrations. Scurvy occurs when the body pool falls below 350 mg.
Vitamin C reduces metal ions in many enzymes and removes free radicals. It protects DNA, protein, and vessel walls from damage caused by free radicals.
Deficiency of vitamin C deficiency results in impaired collagen synthesis and vitamin C deficiency affects collagen-containing tissues like skin, cartilage, dentine, osteoid, and capillary blood vessels.
Vitamin C is also a cofactor in the metabolism of tyrosine and cholesterol and the synthesis of carnitine, neurotransmitters like norepinephrine, peptide hormones, corticosteroids, and aldosterone.
Vitamin C also enhances the absorption of iron from the small intestine and deficiency may contribute to the anemia. Vitamin C is also necessary to convert folic acid to its active metabolite, folinic acid and deficiency results in a deficiency of active form of folic acid, further contributing to anemia.
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
Pathophysiology of Scurvy
- Hyperkeratotic papules around hair
- Hemorrhages around the hair
- Purpura, and ecchymoses
- Fragmentation of hair
- Poor wound healing and breakdown of old scars
- Capillary fragility
- Splinter hemorrhages in the nail
- Loss of scalp hair.
The most vascular skeletal situations are located beneath the periosteum and in the marrow, particularly in the metaphyses and especially adjacent to the most actively growing epiphyses (lower end of femur, upper end of tibia, upper end of humerus).
Subperiosteal hemorrhage may vary from the slight to extensive. It could be big enough to resemble a large tumor in some cases. The clotted blood is either resorbed or transformed to fibrous tissue.
Hemorrhages within the metaphysic interfere with ingrowth of osteoblastic tissue. The metaphyses, in response to hemorrhage, become extremely hyperemic leading to resorption of bone which is seen as a dark zone of radiolucency adjacent to the white line on the X-ray. Fractures and epiphyseal separation may occur [which remodel on vitamin c replenishment].
Hemorrhages throughout the marrow result in the fibrous organization and replacement of hematopoietic tissue resulting in anemia.
Pathologic fractures occur through the metaphysic in infants and the diaphysis in adults.
Calcification of the growth cartilage at the end of the long bones continues, leading to the thickening of the growth plate.
Preexisting bone becomes brittle and undergoes resorption at a normal rate, resulting in microscopic fractures of the spicules between the shaft and calcified cartilage. Trabeculations become thinned and poorly visualized on Xray, called ground glass appearance
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.
Bone changes are often observed only in infants during periods of rapid bone growth.
Beading at the costochondral junctions of the ribs in children [Scorbutic rosary] is seen. The scorbutic rosary is distinguished from rickety rosary (which is knobby and nodular) by being more angular and having a step-off at the costochondral junction. Pectus excavatum- sternum sinks inward is also noticed.
- Gum hemorrhage in erupted teeth esp the upper incisors
- Gum swelling, friability, bleeding, and infection with loose teeth
- Submucosal hemorrhage on endoscopy
- hematochezia, and melena [rare]
- Anemia develops in 75% of patients, resulting from blood loss [gastrointestinal blood loss, and intravascular hemolysis] into and coexistent dietary deficiencies (iron and folate deficiency), altered absorption and metabolism of iron and folate.
- Subconjunctival hemorrhage
- Bleeding within the optic nerve sheath
- Hemorrhagic changes in fundus along with cotton wool spots
- Bleeding into the periorbital area, eyelids, and retrobulbar space also can be seen.
- Proptosis of the eyeball secondary to orbital hemorrhage is a sign of scurvy.
- Hypotension may be observed late in the disease. This may be due to an inability of the resistance vessels to constrict in response to adrenergic stimuli.
- Cardiac enlargement, hemopericardium, and sudden death are known.
- Reversible ST-segment and T-wave changes can be noted on ECG.
- Bleeding into the myocardium and pericardium
- High-output heart failure due to anemia
Infantile scurvy or Barlow’s Disease
Infantile scurvy is uncommon before age 7 months. Early clinical manifestations consist of pallor, irritability, and poor weight gain.
In full-fledged picture, the baby is in extreme pain and tenderness of the arms and, particularly, the legs. The baby is miserable and tends to remain in a characteristic immobilized posture due to subperiosteal pain, with semiflexion of the hips and the knees (frog leg posture).
The body is wasted and swollen as well. Petechiae and ecchymoses are commonly present. Hyperkeratosis, corkscrew hair, and dry eyes are noted.
The voluntary immobilization of the extremities is termed pseudoparalysis.
The gums display a bluish, spongy swelling, especially about the upper central incisor teeth. The teeth are loose and brittle. Petechiae or ecchymoses are found in the skin or the mucous membranes. Hematemesis and hematuria may develop. As the disease worsens, there ensue anorexia, weight loss, progressive anemia, hyperpyrexia, pneumonia, and death.
The lower femur, the upper tibia, and the upper humerus are the favored sites for epiphyseal fracture separations. After treatment is instituted, the fracture heals, and endochondral ossification is reestablished. Although the epiphysis is united in the displaced position, continued longitudinal growth restores the normal contour.
Costochondral separations are typical. The sternum with the cartilaginous portions of the ribs is displaced posteriorly, while the sharp anterior ends of the bony ribs protrude anteriorly. These sharp bony ends form the scorbutic rosary, in contrast to the rounded prominences of the rachitic rosary.
Mild forms of scurvy are seen more commonly. In infants, irritability, restlessness, night cries, pain caused by movement of the extremities, and tenderness over the metaphysis about the knee are the usual symptoms. In adults, pain and tenderness over bony structures are common complaints. A fracture with minimal trauma is suggestive.
Etiology of Scurvy
Scurvy is caused by a prolonged dietary deficiency of vitamin C.
Patients at risk include
- Persons with chronic malnutrition
- Lack of fruits in the diet
- men who live alone
- Restrictive diets because of medical, economic, or social reasons
- Infants fed evaporated or condensed milk formulas
- Patients undergoing dialysis
- inflammatory bowel disease
- Cancer chemotherapy
- Whipple disease
- Dyspepsia (Avoid acidic foods).
Clinical Presentation of Scurvy
Hemorrhage, hyperkeratosis, hypochondriasis, and hematologic abnormalities sum up the scurvy
The initial symptoms of scurvy are nonspecific and include the following:
- Loss of appetite
- Poor weight gain
After 1-3 months of severe or total vitamin C deficiency, patients develop shortness of breath and bone pain. Myalgias may occur because of reduced carnitine production. Skin changes with roughness, easy bruising and petechiae, gum disease, loosening of teeth, poor wound healing, and emotional changes occur. Dry mouth and dry eyes similar to Sjögren syndrome may occur.
Other symptoms include the following:
- Pain and tenderness of the legs
- Swelling over the long bones
Jaundice, generalized edema, oliguria, neuropathy, fever, and convulsions can be seen in later stages.
If not treated, potentially fatal complications, including cerebral hemorrhage or hemopericardium may occur.
- Autoimmune diseases
- Child abuse and neglect
- Clotting factor deficiencies
- Disseminated intravascular coagulation
- Hematologic malignancies
- Hypersensitivity vasculitis
- Necrotizing gingivitis
- Platelet dysfunction
- Vitamin D deficiency and related disorders
Diagnosis of Scurvy
Laboratory tests are usually not helpful in diagnosis which is based generally on clinical findings.
The best confirmation of the diagnosis of scurvy is its resolution following vitamin C administration.
Serum ascorbic acid levels of less than 0.2 mg/dL are deficient, 0.2-0.29 mg/dL are low, and > 0.3 mg/dL are acceptable.
Scurvy generally occurs at levels less than 0.1 mg/dL.
In leucocytes, levels of 0-7 mg/dL reflect a state of deficiency.
Ascorbic acid tolerance test, which quantitates urinary ascorbic acid over the 6 hours following an oral load of 1 g of ascorbic acid in water.
Radiographic findings in infantile scurvy are diagnostic and may show any of the following:
- Subperiosteal elevation
- Fractures and dislocation
- Alveolar bone reabsorption
- The ground-glass appearance of cortex
The knee joint, wrist and sternal ends of the ribs are typical sites of involvement.
The earliest radiologic manifestation of infantile scurvy is generally seen at the distal ends of the radii but distal ends of the femora are most common sites to look for changes.
White line of Fraenkel
A broadened, irregular radiopaque line caused by calcified cartilage between the epiphyseal line and the metaphysis
Small bony spur protruding from the lateral, occasionally the medial, border of the metaphysic at its junction with the epiphysis
Zone of translucency in the metaphysic adjacent to the white line of Fraenkel
Dense line encircling the epiphysis
Other features are
- Ground-glass translucency of the bones
- Thin cortices
- Subperiosteal hemorrhages, which exhibit a soft tissue shadow or a density of ossification
- Epiphyseal fracture-separation
- Costochondral and vertebral angulation of the ribs
- Subperiosteal fractures
These roentgenographic findings are observed best at the ends of rapidly growing long bones.
Treatment of Scurvy
Ensuring adequate vitamin C replenishment in patients with vitamin C deficiency is the hallmark of therapy. In most adult patients, 250 mg of vitamin C 4 times a day for 1-week aids in achieving this goal.
Iron deficiency anemia, folate deficiency, and other vitamin deficiencies are also treated as well.
Prognosis of Scurvy
Typically, scurvy carries an excellent prognosis if diagnosed and treated appropriately.
- Spontaneous bleeding stops within 1 day
- Muscle and bone pain respond quickly
- Bleeding and sore gums heal in 2-3 days
- Ecchymoses heal within 12 days
Bilirubin normalizes in less than 1 week, and anemia is corrected in less than a month.