Rash and Proteinuria

🗒️ Question

A 28 year old woman presents with joint pain, fatigue and a rash on her face that worsens after sun exposure. She also reports intermittent episodes of chest pain that resolve with rest and swelling of her ankles. Her past medical history is unremarkable.

On examination, there is a malar rash on her cheeks sparing the nasolabial folds. There is mild swelling and tenderness in the small joints of her hands. Auscultation of the chest reveals a pericardial rub.

Investigations:

• Haemoglobin: 9.5 g/dL (115–150)

• White cell count: 3.0 × 10⁹/L (4.0–11.0)

• Platelets: 100 × 10⁹/L (150–400)

• CRC: 15 mg/L (<5)

• Urinalysis: Protein 2+, blood 1+

• ANA: Positive

• Anti-dsDNA: Positive

• Complement levels (C3, C4): Low

What is the most likely diagnosis?

(A) Rheumatoid arthritis

(B) Systemic lupus erythematosus

(C) Sjögren’s syndrome

(D) Behçet’s disease

(E) Dermatomyositis