60-year-old male. Smoker with peripheral arterial occlusive disease and abdominal aortic aneurysm. High ESR.

Operative findings: noticeably thickened, white aneurismal wall. Ureters party fused with adventitia.

- Smooth cut through wall of aneurysm (with obliteration of debranching lumbal artery)
- Intima: ruptured atheroma, extending into hyaline fibre parts of wall with inflammatory infiltrates
- The media is not distinguishable from the intima
- The original adventitia is only recognisable by remnant vasa vasorum, nerves and adipocytes.
- The inflammatory infiltrates are dense and predominantly consist of lymphocytes, partly follicular and accompanied by capillaries with prominent endothelium.
- Next to these are a few dense lymphocytic infiltrates

This is a non-infectious inflammation.