Presentation
Known familial Mediterranean fever, complaining of abdominal and back pain.
Patient Data
Age: 45 years
Gender: Male
From the case:
Retroperitoneal fibrosis
Axial C+ portal venous phase
A large amalgamated retroperitoneal periaortic soft tissue mass/sheet-like lesion. It is seen encasing the aorta and both common iliac arteries, associated with mild compression, yet no evidence of significant stenosis.
From the case:
Retroperitoneal fibrosis
FDG-PET confirms the mass lesion, showing a large metabolically active amalgamated retroperitoneal para-aortic soft tissue mass/sheet-like lesion, with maximum SUV 11.7.
Case Discussion
A known case of familial Mediterranean fever, presented with retroperitoneal periaortic soft tissue mass/sheet-like lesion, that was found to be retroperitoneal fibrosis.
There are two types:
- primary (idiopathic): 2/3 of cases
- a manifestation of systemic autoimmune or inflammatory diseases
- secondary: 1/3 of cases
- most commonly due to medications, neoplasms
FDG PET-CT
- not useful as a primary diagnostic tool due to low specificity
- allows detection of remote sites of disease
- may help guide biopsy and assess treatment response
Top differential diagnoses
- chronic periaortitis
- retroperitoneal metastases and lymphoma
- coagulopathic ("retroperitoneal") hemorrhage
- inflammatory abdominal aortic aneurysms