Scurvy in a non–weight-bearing paediatric patient

Scurvy, or hypovitaminosis C, was seen in sailors in the sixteenth to eighteenth centuries on long-distance voyages with restrictions on fresh fruit and vegetables.¹ Often thought of as a historic disease in high-income nations, it is seldom considered high in the differential diagnosis. Sporadic case reports in New Zealand have been published in the literature, but none in a paediatric population.^2,3 We present a case report of scurvy in New Zealand of a child presenting with undifferentiated limp with pathognomonic X-ray findings.

Case report

A 5-year-old boy with non-verbal autism spectrum disorder associated with restricted eating was seen in the orthopaedic clinic with the parents having noted significant discomfort and reduced motion of his left lower extremity and progressive non–weight-bearing status. Physical examination demonstrated non-specific tenderness around his left femur and knee with reduced range of motion. He was admitted for inpatient observation and workup. The patient remained apyrexial with stable normal vital signs during this time.

Plain film imaging demonstrated abnormalities around his distal femur and proximal tibia physeal region. Initial blood work demonstrated neutropenia with white blood cells (2.3x10^9/L), neutrophils (1.3x10^9/L). C-reactive protein was normal (2mg/L). He proceeded to undergo magnetic resonance imaging (MRI), which demonstrated periosteal reaction in the distal femur and proximal tibia. Diffuse bone marrow signal was noted with hyperintense signal on inversion recovery sequences in the femoral and tibial metaphysis mirrored with hypointense signal on T1-weighted sequences. A differential of multifocal infection and chronic recurrent multifocal osteomyelitis was initially made.

Paediatric rheumatology and infectious diseases teams were consulted, and the patient was started on empiric intravenous cephazolin. Further clinical assessment elicited the patient had swollen, bleeding gums. A faint rash was also noted in his lower extremities (Figure 1). Further blood work was subsequently sent off for nutritional deficiencies, with low vitamin C (<1umol/L) eventually returning.

View Figure 1–3.

A detailed history revealed a diagnosis of autism with avoidant/restricted food intake with a restricted diet consisting of solely chicken and biscuits, devoid of any vegetables or fruits. A presumed diagnosis of scurvy was made secondary to this restricted diet. The antibiotics were ceased and a nasogastric tube was inserted for regular feeding and vitamin supplementation. The patient made a marked clinical improvement and was able to ambulate after 3–4 days of inpatient therapy. He was subsequently discharged with community nursing and dietician follow-up. Subsequent clinic reviews showed resolution of his rash and improvement with mobility.

His imaging was subsequently reviewed with a musculoskeletal radiologist, and several pathognomonic features of hypovitaminosis C were identified. Generalised osteopenia and cortical thinning were noted over the distal femoral and proximal tibial epiphyses. Subtle soft tissue shadowing in the distal femur (subperiosteal elevation) was also noted. Plain films demonstrate flaring of the metaphyses with Pelken’s spurs at the tibial metaphysis (Figure 2). White line of Frankel present at the tibial and femoral epiphyses with Trummerfield zone present.⁴ MRI shows marrow oedema around the knee metaphysis with irregularity of the growth plate, with surrounding periosteal and soft tissue oedema (Figure 3). MRI findings are not pathognomonic but when combined clinically aid in establishing the diagnosis.⁵

Discussion

Scurvy is a rare condition caused by severe vitamin C deficiency characterised by gingival bleeding, skin lesions, poor wound healing and bone abnormalities. This case demonstrates the importance of a dietary history as part of the clinical assessment, especially in at-risk populations with restricted eating such as in patients with autism and in the hospitalised elderly.⁶ Early identification and treatment should be instituted as the treatment is relatively simple. However, these vulnerable groups with food selectivity may require ongoing long-term nutritional supplementation to prevent recurrence. The involvement of dietitians is especially useful in evaluation and education. Treatment is typically started empirically when suspected, and patients are expected to make a full recovery.⁷ Although rare in high-income countries, case studies have suggested it is not a historical disease.⁸ The clinician should consider hypovitaminosis C as a rare differential diagnosis in at-risk children. This case highlights the effectiveness of an interdisciplinary approach to a challenging diagnosis with an astute clinical assessment and a high index of suspicion when evaluating children with non-specific lower limb limp.