19th January 2024

A 27-year-old male presents to A&E with a painful and swollen right knee and generalised malaise, which has developed over the past 24 hours.

A 27-year-old male presents to A&E with a painful and swollen right knee and generalised malaise, which has developed over the past 24 hours. He denies any recent falls or injury to the knee. He also reports occasional thick yellow discharge from the penis. He has a past medical history of asthma but is otherwise fit and well. He works as a bartender. Upon further questioning, he admits to having unprotected sexual intercourse around a month ago and had received a text message last week informing him that he has been in contact with someone who has tested positive for chlamydia; however, he has not yet been tested himself. Blood test results showed the following:

Hb 133 g/L (130-180)

MCV 92fL (80-96)

WCC 11.0 x 10⁹/L (4.0-11.0)

CRP 156 mg/L (<10)

Sodium 135 (133–146 mmol/L)

Potassium 4.2 (3.5–5.3 mmol/L)

Creatinine 80 (45–84 μmol/ L)

EGFR >90 

LFTs normal 

Joint aspiration did not reveal the presence of crystals, and the results of the culture are pending.

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