20th February 2025

A 33-year-old man, originally from Türkiye, presents to hospital with small-volume haemoptysis.

A 33-year-old man, originally from Türkiye, presents to hospital with small-volume haemoptysis. He has also noticed intermittent episodes of painful red eyes, painful ulcers in the mouth and scrotum, as well as pain in his joints over the past few months. For a few weeks, he reports feeling generally weak with intermittent diarrhoea and nausea. He has no significant medical or family history.

On examination, he has red sclera in both eyes with some photophobia, anisocoria and slightly reduced visual acuity bilaterally. He has painful aphthous ulcers in his mouth and scrotum. His bloods show the following:

Haemoglobin 98 g/L (normal: 135 – 180 g/L in men)

White Cell Count 13 x 109/L (normal: 4-11 x 109/L)

Sodium 136 mmol/L (normal: 135 – 145 mmol/L)

Potassium 4.8 mmol/L (normal: 3.5 – 5.5 mmol/L)

Urea 6.5 mmol/L (normal: 2.0 – 7.0 mmol/L)

Creatinine 125 micromol/L (normal: 55 – 120 micromol/L)

c-ANCA: Not detectable

p-ANCA: Not detectable

Anti-GBM Antibodies: Not detectable

ANA and ENA: Negative

C3 and C4: In normal range

Creatinine Kinase: 180

Faecal Calprotectin: Negative

A chest radiograph shows an opacity in the right hilar area. Subsequent CT thorax with contrast shows a right-sided pulmonary artery aneurysm with no current evidence of contrast extravasation.

What is the most likely diagnosis?

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