Comparison with earlier CT angiography plates did show presence of new aneurysms, and because a past history of near-fatal aneurysmal rupture existed, after an adequate explanation to the patient, a decision was taken to treat him as active disease. Because the viral serologies were negative, cyclophosphamide and steroids were instituted.9
The other important aspect of this case was to assess disease activity. ESR/CRP was normal, and the patient could not afford a positron emission tomography/magnetic resonance angiography (PET/MR), which can help assess disease activity. Thus, after three doses of intravenous cyclophosphamide, a repeat CT angiography was performed, which showed significant reduction in the size and number of aneurysms.
This highlights the difficulty of monitoring response to treatment in the face of normal inflammatory markers and the role of imaging in monitoring disease activity in patients with polyarteritis nodosa.
Taral Parikh, MD, G.C. Yathish, MD, and Parikshit Sagdeo, MD, are rheumatology DNB students at Hinduja Hospital in Mumbai, India.
Balakrishnan Canchi, MD, is chief of rheumatology at Hinduja Hospital.
Gurmeet Mangat, MD, is a consultant rheumatologist at Hinduja Hospital.
Key Points
- Renal artery involvement in PAN is in the form of intra-renal aneurysms, differentiating it from other mimics.
- Assessing disease activity of such patients may be difficult.
- Consider such aneurysms as evidence of active disease, and treat them accordingly.
- Repeat imaging in such patients could show a reduction in the aneurysms’ size, number or both.
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