19th January 2024

A 37-year-old female presents with pain, swelling and tenderness of multiple joints in both hands.

A 37-year-old female presents with pain, swelling and tenderness of multiple joints in both hands. She states her symptoms started a few months ago and are worse first thing in the morning. She has a past medical history of irritable bowel syndrome and denies any recent infections. On examination, she has bilateral carpometacarpal swelling and tenderness, in addition to swelling bilaterally in the distal interphalangeal joints of the second, third and fifth fingers. Blood test results showed the following.

Hb 143 g/L (130-180)

MCV 92.5fL (80-96)

WCC 6.0 x 10⁹/L (4.0-11.0)

CRP 42 mg/L (<10)

Sodium 139 (133–146 mmol/L)

Potassium 4.9 (3.5–5.3 mmol/L)

Creatinine 60 (45–84 μmol/ L)

EGFR >90 

ESR 20

LFTs normal 

Rheumatoid factor 15 (0-20 u/mL)

Anti-CCP negative 

Faecal calprotectin 127 (50-200 μg/mg)

An x-ray of her joints has been requested. What is the most likely diagnosis?

Select the SINGLE most appropriate option from the list below. Select ONE option only.