IDIOPATHIC MESENTERIC
PANNICULITIS
M. LIMEME, H. ZAGHOUANI BEN ALAYA, H. AMARA,
D. BEKIR, CH. KRAIEM
Imaging department, Farhat Hached Hospital, Sousse, Tunisia
GI26
Introduction
• Synonyms:
retractile mesenteritis, fibrosing mesenteritis,
mesenteric panniculitis, mesenteric lipodystrophy,
liposclerotic mesenteritis, systemic nodular
panniculitis.
• Definitions:
Complex mesenteric inflammatory disorder of
unknown etiology
Objectives
To describe the imaging features of nonspecific inflammation of mesenteric fat
tissue without associated pathology
and to formulate differential diagnosis.
Materials and Methods
• Among two men and a women (mean age 45
years), 2 were paifull,
• Diarrhea was noted in two cases,
• And fever in one case.
• An abdominal mass was found in two cases,
• 3 patients had an inflammatory syndrome.
Results
• The diagnosis was suggested by computed
tomography (CT): (single mass: 2 cases, diffuse
mesenteric thickening: 1 case) and confirmed by
pathology.
• Two patients were treated with corticosteroids.
During the follow-up (mean 56 months) the
panniculitis was stable on CT in 2 cases and
regressed in one case.
• No associated pathology has emerged.
Abdominal pain and diarrhea
CT findings: fat ring sign (arrowheads) and tumoral pseudocapsule (arrow).
Abdominal pain and diarrhea
CT findings: Solid soft tissu mass in the root of small bowel mesentery
ecasing mesenteric vessels.
Abdominal mass and fever
CT findings: extensive infiltration of small bowel mesentery ecasing
mesenteric vessels.
Discussion
Clinical issues
• Symptoms:
Abdominal pain, fever, nausea, vomiting, weight
loss, diarrhea.
Palpable mass.
Incidental finding in an asymptomatic patient.
CT findings
Findings vary depending on predominant
tissue
• Area of subtle increesed attenuation in mesentery
(inflamed fat): solitary/multiple; well/ill defined
• Calcification, enlarged mesenteric lymph nodes,
• Fatty necrotic cystic mass may be seen,
• Infiltration of pancreas or portahepatis,
• Encasement of mesenteric vessels and collateral
vessels: narrowing/occlusion on contrast study
Increesed attenuation in mesentery (red arrow) with well defined outlines:
pseudocapsule.
Encasement of mesenteric vessels and collateral vessels (blue arrow)
CT findings
• « Fat ring » sign: preservation of fat arround
vessels:
- Hypodense fatty halo surrounding mesenteric
vessels and nodules,
- Predominantly seen in mesenteric panniculitis,
- Differentiates scleroing mesenteritis from other
mesenteric processes (lymphoma, carcinoid
tumor, carcinomatosis)
« Fat ring » sign: preservation of fat arround vessels
Horton and al. Radiographics. 2003 ;23(6):1561-7
CT findings
• Pseudocapsule: peripheral band of soft tissue
attenuation that limits normal mesentery from
inflammatory process:
- Seen in mesenteric panniculitis phase,
- Enhancement of pseudocapsule may be seen.
• Thickening/infiltration/displacement/narrowing
of bowel loops.
Pseudocapsule: peripheral band of soft tissue attenuation that limits
normal mesentery from inflammatory process
CT findings
•
-
« Misty mesentery »: nonspecific sign
Increesed attenuation of mesentery,
Evidence of small mesenteric nodes,
No discret soft tissu mass,
Seen in any pathology that infiltrates mesentery
CT findings
• Solid soft tissu mass usually in root of small
bowel mesentery (fibroous tissue)
- Single/large/lobulated/ill-defined increesed
density mass with linear radiating strands
(fibroma-rare)
- Small mesenteric soft tissue nodules of
increesed density (fibromatosis)
MRI findings
• Variable signal intensity due to: inflammation, fat,
fibrosis, vascular and Ca++.
• Mesenteric panniculitis and lipodystrophy:
- T1WI: mixed signal intensity,
- T2WI: mixed signal intensity.
• Retractile mesenteritis: in mature fibrotic reaction
- T1WI: decreesed signal intensity,
- T2WI: very low signal intensity,
- Gradient-écho MR image:
*Narrowing/occlusion of flow in mesenteric vessels
*Collateral vessels are seen
Differential diagnosis
•
•
•
•
•
Non-Hodgkin lymphoma,
Carcinoid tumor,
Mesenteric edema,
Desmoid tumor (Fibromatosis),
Carcinomatosis (mesenteric metastasis)
Differential diagnosis
Non-Hodgkin lymphoma
Differential diagnosis
Carcinoid tumor
Differential diagnosis
Mesenteric edema
Differential diagnosis
Desmoid tumor
Differential diagnosis
Carcinomatosis (mesenteric metastasis)
Treatment
• Steroids, colchicine, immunosuppressive agents:
before fibrotic changes.
• Surgical excision: fibrosis and retraction with
obstructive symptoms.
Conclusion
• Various diseases (usually malignant) can mimic
the imaging features or be associated.
• Pathological verification leads to affirm the
idiopathic mesenteric panniculitis, a benign
entity of unknown pathogenesis.
• Corticosteroid therapy is reserved for
symptomatic patients.