Case Presentation: A 2 year old male with expressive language delay presented with worsening ability to bear weight. The child progressed from refusing to ambulate to refusing to stand over the course of 1.5 weeks. There was parental concern for leg pain which did not improve with ibuprofen. He had mildly decreased appetite the preceding 2 weeks. Parents denied trauma, injury, sick contacts, new environmental exposures, or dietary changes. Immunizations were up to date. The child’s exam on admission demonstrated a non-verbal toddler with refusal to bear weight bilaterally and tenderness in lower extremities when palpated or manipulated. His reflexes and sensation were intact. There was no obvious edema, effusion, ecchymoses, or rash. Laboratory studies were significant for ESR of 30, normal CRP, normal CK, normal CBC, and low MCV. X-ray of the pelvis, femur, tibia/fibula, and foot were negative. An MRI of the brain and spine were normal. An MRI of the lower legs demonstrated bilateral metaphyseal marrow signal abnormality and adjacent edema, greatest about the knees, suggestive of a nutritional/metabolic deficiency, specifically scurvy. There was no evidence of fracture or mass, and metastatic disease was considered unlikely due to the bilateral and symmetric distribution. A more detailed diet history revealed that the child exhibited restrictive eating, where his diet consisted of mostly cereal, bread, and tortillas. He typically refused vegetables, fruits, and most meats. A repeat exam demonstrated additional findings of anterior maxillary gum darkening (reddish-purple hue), hyperpigmented non-blanching patches along bilateral malleoli (present for months after minor injury to the sites), and bilateral knee edema. A vitamin C level was obtained and the patient was given IV ascorbic acid. He was discharged home with an oral ascorbic acid regimen and instructions to follow up with the pediatrician and our Feeding Program. After discharge, the patient’s vitamin C level resulted as 0.1 mg/dL (reference range is 0.2-2.1 mg/dL). Two months after his admission, his parent reported normal ambulation including ability to run and play at the same level as other children his age. The child continued to take daily ascorbic acid and a multivitamin.
Discussion: In a 1 month period, our pediatric hospital admitted 3 children with language delay and/or diagnosed autism with impaired weight-bearing, later found to have vitamin C deficiency. Weight-bearing and ambulation improved with vitamin C supplementation. These children underwent extensive lab tests, consultations, and imaging including MRIs (with sedation) before diagnosis was determined. Certain history and exam findings may have clued providers in to a diagnosis of scurvy earlier. Common features included: suspected lower extremity pain by caregivers, chronic restrictive eating or change in appetite, bilateral knee swelling or limited range of motion, and elevated ESR. Features classically associated with scurvy such as delayed wound healing and gingival swelling were variably present.
Conclusions: Although vitamin C deficiency is considered rare in the United States, it may be underdiagnosed in pediatric children with autism spectrum disorder. These children may undergo extensive testing prior to achieving a diagnosis. Evaluation for vitamin C deficiency and early treatment with ascorbic acid is a low-risk and low-cost intervention in non-verbal children who present with impaired weight-bearing, are stable, and have no concerning acute neurologic changes.