Journal of Medicine Vol 4 - Amrita Institute of Medical Sciences and ...

Amrita Journal of Medicine
Radiology Quiz
Chandramohan, R. Kannan, S. Moorthy
DIAGNOSIS:
Polyarteritis Nodosa.
DISCUSSION:
Polyarteritis Nodosa is a systemic fibrinoid necrotizing vasculitis of medium sized and small muscular arteries (and
sometimes small veins) that can involve any organ and in varying degrees.
PAN occurs twice as frequently in men as in women, and it is found in all age groups but most commonly in the 5th–
7th decades.
The kidneys may be involved in 70%–80% of cases; the gastrointestinal tract, peripheral nerves, and skin in 50%;
skeletal muscles and mesentery in 30%; and the central nervous system in 10%.
Many of the clinical symptoms are related to organ ischemia secondary to arterial branch occlusions. Aneurysm
rupture is a less common cause of pain. Arthralgias are noted in 50% of patients, as are peripheral neuropathies. Renal
involvement including proteinuria and hypertension are found in 75%. Branch vessel occlusions can lead to multiple
renal infarcts.
A definitive diagnosis may be made in certain clinical settings by performing tissue biopsy from a symptomatic organ
site.
Angiography is considered the gold standard for diagnosis. The main angiographic findings in polyarteritis nodosa are
small aneurysms, vascular ectasia, and occlusive vascular disease manifesting as luminal irregularity, stenosis, or occlusion
of small and medium-sized arteries of the viscera. These abnormalities are detected in 40–90% of patients who have
just developed clinical symptoms.
The most well known angiographic feature is the presence of so-called microaneurysms in medium or small arteries.
CECT can demonstrate aneurysms of the hepatic, pancreatic, and renal arteries and lesions inside these organs caused
by either aneurysm rupture or thrombosis. MDCT can be used as a noninvasive imaging technique for diagnosing small
aneurysms in patients with suspected polyarteritis nodosa and for following up these patients after immunosuppressive
treatment.
In this particular case multiple microaneurysms were detected in both renal arteries. Multiple small infarcts were
noted in both the kidneys producing a moth eaten appearance. Aneurysms were also noted in the splenic artery and
internal iliac artery branches and lab investigations revealed Positive ANA, elevated as DNA antibody and elevated ESR
were detected.
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