Rheumatology

A 64-year-old woman presents to her GP with pain in several of her small hand joints for more than 8 weeks. Blood investigations demonstrate the following: https://www.niso.org/standards/z39-96/ns/oasis-exchange/table">

Haemoglobin

8.1 g/dL

White cell count

14 × 10⁹/L

Platelet count

560 × 10⁹/L

Sodium

134 mmol/L

Potassium

4.1 mmol/L

Urea

5.4 mmol/L

Creatinine

140 mcmol/L

C-reactive protein

120 mg/L

Rheumatoid factor

negative

Anti-citrullinated protein antibody (ACPA)

positive