You are in: eMedicine Specialties > Radiology > PEDIATRICS ScurvyArticle Last Updated: Jun 27, 2007AUTHOR AND EDITOR INFORMATIONAuthor: Bruce M Rothschild, MD, Professor of Medicine, The Northeastern Ohio Universities College of Medicine; Director, Arthritis Center of Northeast Ohio; Adjunct Professor, Department of Biomedical Engineering, University of Akron Bruce M Rothschild is a member of the following medical societies: American Association for the Advancement of Science, American College of Rheumatology, American Federation for Clinical Research, American Heart Association, American Society for Clinical Pharmacology and Therapeutics, International Skeletal Society, New York Academy of Sciences, and Sigma Xi Coauthor(s): Jeno Imre Sebes, MD, Professor, Department of Radiology, University of Tennessee Health Science Center at Memphis Editors: Michael A Bruno, MD, Associate Professor, Departments of Radiology and Medicine, Pennsylvania State University College of Medicine; Director, Radiology Quality Management Services, Milton S Hershey Medical Center, Pennsylvania State University College of Medicine; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Marta Hernanz-Schulman, MD, FAAP, Professor, Radiology, Radiological Sciences, and Pediatrics, Director, Department of Pediatric Radiology, Radiologist-in-Chief, Director, Department of Diagnostic Imaging, Vanderbilt University Medical Center, Vanderbilt Children's Hospital; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Felix S Chew, MD, MBA, EdM, Professor, Department of Radiology, Vice Chairman for Radiology Informatics, Section Head of Musculoskeletal Radiology, University of Washington Author and Editor Disclosure Synonyms and related keywords: vitamin C deficiency, ascorbutism, scorbutism, Barlow disease, Barlow's disease, subperiosteal hematoma syndrome, hypovitaminosis C, collagen defects, hemorrhagic diathesis, abnormalities in bone maturation, epiphyseal disease, lifting of the periosteum, hemarthroses INTRODUCTIONBackgroundThe term scurvy is derived from the Nordic word skyrbjugr, meaning swelling or edema. It has also been suggested that the term is derived from the Old Icelandic words skyrbugr, scarby, or skurvic. Scurvy is caused by a lack of vitamin C and manifests as collagen defects, hemorrhagic diathesis, abnormalities in bone maturation, epiphyseal disease, lifting of the periosteum, and hemarthroses.PathophysiologyScurvy is the direct result of vitamin C deficiency. Vitamin C is required for prolyl and lysyl hydroxylase activity and is essential for collagen synthesis. Defective collagen compromises skin, joint, bone, and vascular integrity. Vitamin C is also required for carnitine synthesis, and it is critical for fatty acid transportation into the mitochondria. This oxidative metabolism is also critical for muscle function. Scurvy is usually caused by a lack of dietary vitamin C related to inadequate food intake, the destruction of vitamin C in food caused by cooking and canning, or the absence of fresh fruit in the diet. Malabsorption, tobacco use, chronic oxidative stress (eg, HIV infection, inflammatory bowel disease, endotoxemia, diabetes, heat stress), hemodialysis, and therapy with the folic acid antagonist aminopterin all reduce the level of vitamin C in the body. FrequencyUnited StatesScurvy is not common in the US, though in one recent study, vitamin C deficiency was present in up to 23% of respondents.1 Young children and older persons are predisposed to scurvy because of their diet or the overpreparation of food (cooking destroys vitamin C). Smokers, non-Hispanic black males, and individuals who do not use vitamin supplements have an increased risk of vitamin C deficiency.1 InternationalInternationally, scurvy is rare. Young children and older persons are predisposed to scurvy because of their diet or the overpreparation of food (cooking destroys vitamin C). Mortality/Morbidity
RaceNo data are available. SexMales and females are equally affected. AgeThose most commonly affected are children aged 6-18 months; however, adults can also be affected. Unless the mother had a deficiency herself, the maternal contribution of vitamin C is generally protective of infants younger than 6 months. AnatomyPerivascular hemorrhage and lifting of the periosteum caused by hemorrhage are the main anatomic alterations depicted on radiographs. This hemorrhage is due to increased capillary fragility. In scurvy, there is normal mineralization of osteoids; however, the overall amount is decreased. This process is distinct from that in rickets, in which the lack of vitamin D results in defective mineralization of a normal organic matrix. Clinical DetailsThe normal total-body pool of vitamin C is 1500 mg. The normal plasma level of vitamin C is 0.7-1.2 mg/dL. Scurvy occurs when the total-body vitamin C level is below 350 mg. The elimination of vitamin C from the diet results in scurvy within 2-3 months. A total vitamin C intake of 10 mg/d maintains the total-body pool above 350 mg and prevents scurvy. Clinical symptoms include the following:
Individuals with renal complications who are receiving dialysis may be susceptible to vitamin C deficiency. Dietary restrictions associated with dialysis generally limit the amount of potassium that a patient may ingest in order to avoid hyperkalemia. Unfortunately, many foods rich in potassium, such as orange juice, strawberries, and broccoli, are also the best sources of vitamin C. In addition, the dialysis process removes a significant amount of vitamin C from the body. This is further compounded by the fact that the use of vitamin C supplements may lead to oxalosis, which can cause renal and liver problems. Often, physicians have avoided vitamin supplementation in order to safeguard against oxalosis. New research suggests that the benefits of vitamin C supplementation and advances in dialysis techniques may lead to an increased use of vitamin C to control anemia for dialysis patients.4 Preferred ExaminationRadiography is the preferred imaging examination for diagnosis. Serum vitamin C levels can be obtained to confirm the diagnosis of scurvy. Limitations of TechniquesSkull changes may be below the resolution of computed tomography (CT) or magnetic resonance imaging (MRI). Change in skull shape is not diagnostic, as this finding may also be seen with hemolytic anemia, other causes of bone marrow hyperplasia, and rickets. DIFFERENTIALSGastrointestinal Bleeding, Lower Juvenile Rheumatoid Arthritis Lead Poisoning Leukocytoclastic Vasculitis Osteomyelitis, Acute Pyogenic Osteoporosis, Involutional Psoriatic Arthritis Rickets Sickle Cell Anemia, Skeletal Thalassemia Other Problems to Be ConsideredCopper deficiency
RADIOGRAPHFindingsSome authors have suggested that the most diagnostic radiologic finding of vitamin C deficiency is a large, fluctuant, parietal swelling, which is apparently caused by subperiosteal hemorrhage. This author, however, considers long bone changes to be better clinical identifiers of vitamin C deficiency than parietal swelling. The epiphyses and periosteum also become easily detachable because of hemorrhage below the periosteum. Separation of the metaphyseal plate from the diaphysis, epiphyseal clefts, and malalignment of the metaphysis may also occur. A circular, opaque radiologic shadow often surrounds epiphyseal centers of ossification. This ring of increased opacity formed around the ossification center of long bone epiphyses is known as the Wimberger sign, which may result from bleeding or attachment movement. Vitamin C deficiency is characterized by cortical thinning, which is sometimes described as a “pencil-point” cortex. Decreased trabeculae produce a decrease in radiopacity, resulting in a transparent aspect similar in appearance to ground glass. The increased opacity of distal diaphysis may be accompanied by a subjacent zone of decreased opacity. The thickening is known as a Frankel line, and the lucent zone on the diaphyseal side of the Frankel line (secondary to poorly formed trabeculae) is known as the Trümmerfeld zone. Its origin might be related to vascular compromise, similar to increases in bone density noted with avascular necrosis. Costochondral junctions of the first 6 or 8 thoracic ribs may be expanded; this change may be related to fracturing of the zone of provisional calcification during normal respiration. The costochondral junctions are rounded and appear smooth, knobby, and steplike. The enlargement of the costochondral junctions simulates that seen in rickets. The zone of proliferating cartilage cells is distorted, producing spicules from the metaphysis into the epiphyseal plate region. The zone of temporary calcification broadens, producing a wide, radiopaque metaphyseal band. Subjacent to this is a zone of poor-quality trabeculae, which appears radiolucent. A steplike lateral projection is found at the epiphyseal line in patients who are severely affected. Scorbutic changes are radiologically more severe in the lower extremities, whereas scorbutic changes seen in rickets are allegedly more severe in the upper extremities. Metaphyseal “beaks” and transverse lines of increased or decreased opacity may be seen in scurvy. The “beaks,” known as Pelkan spurs, are associated with fractures of the Trümmerfeld zone. They may be produced by lateral growth of the metaphyseal calcification zone and are associated with periosteal elevation. Subepithelial marginal clefts may also be present. Skull changes may produce a “hair-on-end” or crew-cut appearance secondary to marrow hyperplasia in response to anemia. Examination of individuals with known scurvy reveals other skull changes (eg, porotic hyperostosis, also described as a hair-on-end appearance, and marrow hyperplasia); however, no sphenoid changes are reported. Sphenoid porosity has not been shown to be caused by scurvy. Subperiosteal hemorrhages are visualized only in the healing phase of scurvy, and these are almost invariably paraepiphyseal in distribution. Epiphyseal separation often results. Healing scurvy also appears with the loss of the scurvy line, in which the only residual manifestation is a double line of ossification at the original active site.Degree of ConfidencePeriosteal elevation and epiphyseal separation both appear to be relatively specific for scurvy. Osteoporosis is a nonspecific finding. The periosteal reaction of syphilis is more generalized than that of scurvy and is usually thick or multilaminated. Syphilis, often called the great imitator, produces metaphyseal beaking similar to that noted in scurvy; however, syphilis does not produce radiopaque metaphyseal lines. Although periosteal elevation may occur and produce a linear elevated area in patients, a spiculated periosteal reaction does not occur in scurvy. Metaphyseal lesions caused by syphilis are beaklike, whereas those caused by scurvy involve epiphyseal separation. Epiphyseal separation is a known complication of scurvy; however, it is also seen in cases of child abuse. The periosteal reaction resulting from child abuse is more generally distributed and is associated with a fracture. Costochondral beading is more common with rickets than with scurvy. Skull-marrow hyperplasia is more likely to result from hemolytic anemia or anemia related to parasitic infestation. NUCLEAR MEDICINEFindingsTechnetium bone scans are not routinely performed in patients with scurvy; however, increased uptake at the distal metaphyses and the epiphyses and formation of a rachitic rosary are hypothetically possible. INTERVENTIONNo radiologic interventions are indicated, although the dietary provision of recommended daily allowances of vitamin C is generally recommended. Medical/Legal Pitfalls
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