Scurvy-a forgotten disease with an unusual presentation

Introduction

Scurvy is an uncommon disease with a wide clinical spectrum, and therefore easily misdiagnosed when it does appear. Unusual presentations, such as hemarthrosis, spontaneous ecchymosis, muscle bleeds, proptosis, extradural haematoma, hard swollen legs and haemorrhagic pleural effusion due to vitamin C deficiency, have been reported in the past. ^1–6 We report an unusual case of scurvy presenting only as arthritis with no involvement of shaft of bones. Although joint involvement may be one of the manifestations of the disease, scurvy presenting only as arthritis has not been reported in the literature.

Case history

A six-year-old female child presented with progressively increasing joint pain and swelling involving the bilateral ankle, knee and hip joints for the past three months. There was no history of fever, rash, photophobia, redness of eyes, easy bruisability or gum bleeds. On examination, there was tenderness, swelling, increased temperature and restriction of movements around these joints. However, no swelling or tenderness was present over the shaft of long bones. Systemic, general physical and ocular examinations were normal.

X-rays of the joints revealed marked periarticular osteopenia and increased joint space (Figure 1). Ultrasonography (USG) revealed mild effusion in the bilateral hip and knee joints. Erythrocyte sedimentation rate (ESR) was 38 mm/h. Serum C-reactive protein (CRP) was 24 mg/L. Haemogram and anti-streptolysin O (ASO) titres were within normal limits. Rheumatoid factor and antinuclear antibodies (ANA) were negative. The patient was diagnosed with juvenile idiopathic arthritis (JIA) and was started on naproxen 20 mg/kg/day q12 h. After two weeks of treatment, the patient showed some clinical improvement and was discharged on naproxen. Within four weeks of discharge, she again presented with worsening of the same symptoms. Examination findings were the same as at initial presentation. A repeat X-ray of knee joints revealed a zone of rarefaction (scurvy line) and spur formation at metaphysis (Figure 2). These findings are diagnostic for scurvy. Retrospective, detailed dietary intake assessment also revealed poor consumption of fruits and vegetables by the patient. Naproxen was stopped and patient was started on vitamin C 200 mg/day q6 h. Within the first week of treatment, joint pain and tenderness decreased and by the third week the patient was completely recovered.

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Figure 1

X-ray knee joints showing marked periarticular osteopenia and increased joint space

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Figure 2

X-ray knee joints showing signs of scurvy (arrow showing scurvy Line, i.e. zone of rarefaction)

Discussion

Scurvy, a state of dietary deficiency of vitamin C, is an ancient disease. The human body lacks enzyme L-gulonolactone oxidase and thus lacks the ability to synthesize vitamin C. ⁷ Therefore, consumption of fruits and vegetables or diets fortified with vitamin C are essential to prevent scurvy. Scurvy can occur at any age with peak incidence between 6 to 24 months. Initial presentation is non-specific and includes loss of appetite, poor weight gain, diarrhoea, tachypnoea and fever. Specific clinical features include tenderness and swelling over long bones, pseudoparalysis, frog leg posture, scorbutic rosary, poor wound healing and gum bleeding. Hyperkeratosis, coiled body hairs and xerosis are typically observed in adults. ⁸ Due to the wide spectrum of symptoms, scurvy is commonly misdiagnosed in earlier stages. In a retrospective paediatric study (n = 28), 86% of scurvy cases were previously misdiagnosed. ⁹ Laboratory tests for vitamin C assay are unsatisfactory. Thus, diagnosis is usually based on the characteristic clinical picture, the radiographic appearance of long bones and a history of poor vitamin C intake. ¹⁰

In the present case, the patient presented with clinical features of arthritis only, with no involvement of shaft of bones. Although joint involvement can occur in scurvy, scurvy presenting only as arthritis has not been reported in literature yet. Initial X-rays of the patient revealed periarticular osteopenia (Figure 1) which can be seen in both JIA and scurvy. ¹¹ Thus, in its early stages, scurvy can mimic JIA radiologically. Diagnostic radiological findings of scurvy, that is, zone of rarefaction (scurvy line) and multiple spurs at metaphysis, were reported in later X-rays in the present case (Figure 2). The classical radiographic picture (in later X-rays) and poor dietary intake of vitamin C, together with the prompt and complete resolution of arthritis after vitamin C therapy in this patient, leaves no doubt about the diagnosis.

Thus, scurvy should be thought of as a possible diagnosis in refractory arthritis, as failure to diagnose this disease can potentially lead to expensive and unnecessary medical tests, when in fact a very simple treatment that can prevent severe morbidity and even death, is available.