Humans lack the ability to synthesize vitamin C, because of mutation in the gene coding for l-gulonolactone oxidase, the enzyme required for the biosynthesis of vitamin C . However, vitamin C is an essential micronutrient. Scurvy occurs as a result of decreased vitamin C consumption or absorption. The prevalence of scurvy in children is not known, but certain populations are at risk. The two largest cohorts of scurvy cases in children have been reported by Noble et al., who presented 23 case studies of scurvy in children with restricted diets, including children with autism, developmental delay, and cerebral palsy , and Ratanachu-Ek et al., who reviewed 28 cases of scurvy in Thai children, almost all of whom presented with inability to walk. Of the cases reviewed by RatanachuEk et al., 89 % were supplemented with ultra heat treated (UHT) milk .
The earliest manifestations of scurvy are nonspecific constitutional symptoms, such as asthenia, anorexia, and weight loss. Musculoskeletal manifestations may be the presenting symptoms in scurvy; in 80 % of cases, the manifestations of scurvy include arthralgia, myalgia, hemarthrosis, and muscular hematomas . As in our case, inability to walk is a very common presenting musculoskeletal symptom in children with scurvy .
Poorly formed collagen leads to dystrophic or corkscrew hairs, gingival hyperplasia, and weakened blood vessel walls, causing bleeding in the skin, joints, and other organs . Follicular hyperkeratosis and perifollicular hemorrhages are also common, particularly over the lower limbs, as was a prominent feature in our case. Subperiosteal hematomas may be palpable as painful swellings over the distal end of the femur and tibia. Intramuscular hematomas may cause compartment syndrome . Our patient had large, uncomplicated intramuscular hematoma that resolved spontaneously.
Laboratory test abnormalities in scurvy are nonspecific; anemia is frequent manifestation. Our patient had severe hemolytic anemia that required multiple blood transfusions. In severe cases, anemia can lead to cardiac hypertrophy and high output heart failure .
The causes for anemia in scurvy could be multifactorial, resulting from blood loss, concomitant vitamin deficiencies, and decreased iron absorption . An elevated erythrocyte sedimentation rate and C-reactive protein level can be seen in some cases . In our case, the sedimentation rate was mildly elevated, which could cause confusion with an inflammatory process.
Radiographic changes may include osteonecrosis, osteopenia, and cortical thinning with periosteal proliferation. Many signs have been reported in the literature, such as the Frankel sign (zone of calcification at the margin of growth plate), Wimberger sign (calcification around the epiphysis) and scurvy line (lucency adjacent to metaphyseal sclerotic line) . In our case, all of these findings were absent. We speculate that a good level of vitamin D halted these changes.
A meticulous history, including dietary history and physical examination, can help to reach the diagnosis of scurvy. Usually, work up is not necessary to confirm diagnosis of scurvy.
Vitamin or mineral deficiencies other than vitamin C deficiency may accompany scurvy, therefore the prudent clinician will also check for concomitant micronutrient deficiencies, testing levels of zinc, iron, folate, and vitamin B12. In our case, RBC folate and serum iron were low.
Known risk factors for scurvy in children are oral aversions, cerebral palsy, developmental delay, and autism. Our patient had developmental delay as a result of complicated prematurity.
Scurvy is preventable disease. The daily intake of vitamin C must be no lower than 10 mg/day and the body pool no smaller than 350 mg to avoid scurvy . The recommended daily intake is variable according to the child’s age . Treatment of scurvy is based on replenishing the level of vitamin C to counteract the symptoms. There is no established regimen for vitamin C supplementation in scurvy. Supplementation with 1 g/day of oral vitamin C for 2 weeks is the usual treatment . However, other regimens have been tried, such as 100 to 200 mg/day for a longer period . Once vitamin C deficiency has been treated, prevention and correction of underlying conditions are required in order to prevent recurrence.
Following treatment with vitamin C, spontaneous bleeding, oral symptoms and constitutional symptoms begin to improve within days, while bony changes and ecchymoses may take several weeks to resolve . Overall improvement of symptoms after the administration of ascorbic acid is a confirmatory approach for the diagnosis.