19th January 2024

A 32-year-old male presents to A&E with a one-week history of pain, swelling and stiffness in his left knee and ankle.

A 32-year-old male presents to A&E with a one-week history of pain, swelling and stiffness in his left knee and ankle. He has also noticed pain and redness in his right eye for the past day and a rash on the soles of his feet. He is normally fit and well and has no past medical history. Upon further questioning, he reports having an episode of unprotected intercourse one month ago whilst on holiday, and has had a few episodes of yellow discharge from his penis. Blood test results showed the following.

Hb 140 g/L (130-180)

MCV 92fL (80-96)

WCC 5.0 x 10⁹/L (4.0-11.0)

CRP 96 mg/L (<10)

Sodium 138 (133–146 mmol/L)

Potassium 4.9 (3.5–5.3 mmol/L)

Creatinine 68 (45–84 μmol/ L)

EGFR >90 

ESR 3

LFTs normal 

Rheumatoid factor 8 (0-20 u/mL)

Urate 230 (200-430 μmol/L)

A joint aspiration is performed. 

What is the most likely finding on joint fluid analysis?

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