Sclerosing Mesenteritis

Background

This is an uncommon mesenteric disease with fewer than 300 cases reported. Patients most frequently report symptoms and signs of abdominal pain, abdominal mass, or symptoms related to bowel obstruction. However, many patients have no symptoms, and the disease is discovered incidentally. Likewise, laboratory tests, including imaging studies, are also considered nonspecific.

The definitive diagnosis thus requires a biopsy. The disease may present as a single mass, multiple masses, or as diffuse thickening of the mesentery. The majority of reported cases have involved the small bowel mesentery, sole involvement of the mesocolon has been well documented in approximately 20% of cases. Other rare intra-abdominal sites that have been involved are the mesoappendix, peripancreatic area, omentum, and pelvis.

EPIDEMIOLOGY CHARACTERIZATION

SYNONYMS Mesenteric lipodystrophy
Mesenteric panniculitis
Retractile mesenteritis

AGE RANGE-MEDIAN >50 years

SEX (M:F)
Males

DISEASE ASSOCIATIONS CHARACTERIZATION

MULTIFOCAL OR SYSTEMIC FIBROSCLEROSIS
Semin Diagn Pathol 1998;15:161–173

Disease spectrum that also includes retroperitoneal fibrosis, sclerosing mediastinitis, Riedel thyroiditis, and orbital pseudotumor

HIV

Sclerosing mesenteritis: an unusual cause of abdominal pain in an HIV-positive patient.

Venkataramani A, Behling CA, Lyche KD.

Department of Medicine, University of California, San Diego 92103-8413, USA.
Am J Gastroenterol 1997 Jun;92(6):1059-60 Abstract quote
Sclerosing mesenteritis is a rare, idiopathic, and benign mesenteric lesion that is characterized by fat necrosis, fibrosis, and chronic inflammation.

We report a case of sclerosing mesenteritis presenting as recurrent abdominal pain in an HIV-positive patient. Because of the wider differential diagnosis in such cases, the patient underwent an extensive workup culminating in a laparoscopy with biopsy. Tamoxifen has been shown to be useful in the treatment of desmoid tumors and idiopathic retroperitoneal fibrosis.

We present the first case of sclerosing mesenteritis to respond to tamoxifen therapy. Because this drug is relatively safe and simple to dose, its utility as therapy for patients with this benign but debilitating disease should be considered.

INFLAMMATORY PSEUDOTUMOR

Concomitant sclerosing mesenteritis and inflammatory pseudotumor simulating gastric lymphoma or linitis plastica.

Gincherman Y, Langer JE, Miller L.

Department of Surgery, Hospital of the University of Pennsylvania, University of Pennsylvania School of Medicine, Philadelphia, USA.
J Surg Oncol 1995 Jun;59(2):136-8 Abstract quote
Both inflammatory pseudotumors and sclerosing (retractile) mesenteritis are uncommon conditions of unknown origin. A number of authors have reported patients presenting with complaints that were attributed to one or the other of these entities.

In our review of the literature, we were unable to find a single case report of mixed abdominal findings that could be explained by the presence of both conditions. We report a case of the patient presenting with abdominal mass that was identified as having features of both sclerosing mesenteritis and inflammatory pseudotumor on pathologic diagnosis.

NEPHROPATHY

Minimal change nephropathy associated with sclerosing mesenteritis.

Vernace MA, Bellucci AG, Mossey RT, Susin M, Mailloux LU, Wilkes BM, Katz S, Eskreis D.

Department of Medicine, North Shore University Hospital, Manhasset, NY 11030, USA.
Nephron 1996;73(3):473-6 Abstract quote
A 65-year-old man with sclerosing mesenteritis developed the nephrotic syndrome. Percutaneous renal biopsy revealed classical histologic findings of minimal change nephropathy with a mild interstitial nephritis.

Immunomodulation with prednisone led to a rapid and complete remission of the proteinuria but did not alter the course of the underlying sclerosing mesenteritis. The association of lymphomatous and nonlymphomatous neoplasms with minimal change nephropathy has been well-described. Our review of the literature indicates a parallel association of malignant lymphoma with sclerosing mesenteritis and a variety of disorders that constitute a spectrum of disease.

The occurrence of this histopathologic form of renal injury and therapeutic response in the setting of a known lymphoreticular disorder suggests a role for a generalized alteration in cell-mediated immunity and not a tumor-induced elaboration of a factor(s) that directly damages the glomerular filtration barrier.

PROTEIN LOSING ENTEROPATHY

Protein-losing enteropathy: first manifestation of sclerosing mesenteritis.

Horing E, Hingerl T, Hens K, von Gaisberg U, Kieninger G.

Department of Internal Medicine, Krankenhaus Bad Cannstatt, Stuttgart, Germany.
Eur J Gastroenterol Hepatol 1995 May;7(5):481-3 Abstract quote
OBJECTIVE: To report the case of an unusual form of protein-losing enteropathy.

PATIENT: A 54-year-old patient with hypoechoic tumours resembling lipomas in the mesentery.

INTERVENTIONS: Following examination by ultrasound and computed tomography, the well-known intestinal and extra-intestinal forms of protein-losing enteropathy were excluded and a diagnostic laparotomy was performed. The whole mesentery was infiltrated by a large unresectable tumour. Histological examination showed that it was a sclerosing mesenteritis.

MAIN OUTCOME MEASURES: Steroid therapy dramatically improved the protein-losing enteropathy.

CONCLUSION: Pathogenically, the enteropathy may be interpreted as the result of disturbed lymphatic drainage caused by the sclerosed mesentery.

PATHOGENESIS CHARACTERIZATION

Sclerosing mesenteritis, mesenteric panniculitis and mesenteric lipodystrophy: a single entity?

Emory TS, Monihan JM, Carr NJ, Sobin LH.

Department of Hepatic and Gastrointestinal Pathology, Armed Forces Institute of Pathology, Washington, DC 20306-6000, USA.

Am J Surg Pathol 1997 Apr;21(4):392-8 Abstract quote

We reviewed 84 cases coded as mesenteric lipodystrophy (ML), mesenteric panniculitis (MP), or retractile mesenteritis and sclerosing mesenteritis (SM), grading fibrosis, inflammation, and fat necrosis, and evaluating clinical subgroups.

There was no gender or racial predominance. Patient age range was 23-87 years (average 60). Patients most often presented with abdominal pain or a palpable mass. A history of trauma or surgery was present in four of 84 patients. The most common site of involvement was the small bowel mesentery as a single mass (58 of 84) with an average size of 10 cm, multiple masses (15 of 84), or diffuse mesenteric thickening (11 of 84). All patients had some degree of fibrosis, chronic inflammation, and fat necrosis. Although a few patients showed a sufficient prominence of fibrosis, inflammation, or fat necrosis to permit a separation into SM, MP, or ML, respectively, in most patients these three components were too mixed for a clear separation. The clinical, demographic, and gross features did not help in defining these three entities. Contributors diagnosed 12 as sarcoma. Of 39 patients followed beyond the postoperative period, none died of these lesions.

We conclude that SM, MP, and ML appear to represent histologic variants of one clinical entity, and in most cases "sclerosing mesenteritis" is the most appropriate diagnostic term.

LABORATORY/RADIOLOGY CHARACTERIZATION

Mesenteric panniculitis: findings on CT, MRI, and angiography. Case report.

Badiola-Varela CM, Sussman SK, Glickstein MF.

Department of Radiology, Hartford Hospital, Connecticut.
Clin Imaging 1991 Oct-Dec;15(4):265-7 Abstract quote
The computed tomography (CT), magnetic resonance (MR), and angiographic features of a case of mesenteric panniculitis are presented. The MR characteristics of this rare disorder have not previously been reported.

The value of MR in arriving at the preoperative diagnosis of this disorder is discussed.

Sclerosing mesenteritis: imaging findings in 17 patients.
Sabate JM, Torrubia S, Maideu J, Franquet T, Monill JM, Perez C.

Department of Diagnostic Radiology, Hospital de Sant Pau, Universitat Autonoma de Barcelona, Spain.
AJR Am J Roentgenol 1999 Mar;172(3):625-9 Abstract quote
OBJECTIVE: The purpose of this study was to evaluate the radiologic findings of sclerosing mesenteritis and to describe certain signs that suggest the diagnosis.

CONCLUSION: Sclerosing mesenteritis represents a single disease with two radiologically different variants. In an appropriate clinical setting, radiologic features can suggest the diagnosis, delineate the extent of the process, and prescribe or limit surgical procedures. The "fat ring" sign and the presence of a tumoral pseudocapsule are important findings for the diagnosis of the disease.

GROSS APPEARANCE/CLINICAL VARIANTS CHARACTERIZATION

General

VARIANTS

BILE DUCT

Concomitant sclerosing mesenteritis and bile duct fibrosis simulating Klatskin's tumor.

Medina-Franco H, Listinsky C, Mel Wilcox C, Morgan D, Heslin MJ.
J Gastrointest Surg 2001 Nov-Dec;5(6):658-60 Abstract quote
Sclerosing mesenteritis is an uncommon benign condition that should be included in the differential diagnosis of abdominal masses.

We present the first reported case of this condition in association with idiopathic bile duct fibrosis simulating Klatskin's tumor. A review of the literature regarding both clinical entities is presented.

CALCIFICATIONS

Mesenteric lipodystrophy with fever of unknown origin and mesenteric calcifications South Med J 1999;92:513–516.

PANCREAS

Sclerosing mesenteritis involving the pancreas: two cases of a rare cause of abdominal mass mimicking malignancy Eur J Gastroenterol Hepatol 1999;11:1323–1329

Sclerosing mesenteritis seen clinically as pancreatic pseudotumor: two cases and a review.

Sheikh RA, Prindiville TP, Arenson D, Ruebner BH.

Department of Gastroenterology, University of California, Davis, USA.
Pancreas 1999 Apr;18(3):316-21 Abstract quote
Sclerosing mesenteritis is an uncommon nonneoplastic inflammatory process in the mesentery that is seen as a pseudotumor, usually involving the small bowel mesentery, the mesenteric fat, and less commonly, the mesentery of the large bowel.

We report two cases of sclerosing mesenteritis and review the literature on this rare disease. Both patients had pain, profound weight loss, and a mass on computed tomography (CT) scan of the abdomen. The provisional diagnosis was pancreatic neoplasm on the basis of clinical presentation and imaging studies. The diagnosis of sclerosing mesenteritis was established by histologic findings in biopsy material obtained at laparotomy in both cases.

Interval histologic studies in one patient who had a high CA 19-9 level, progressive biliary ductal and partial duodenal compression, revealed a transitional histologic pattern from predominant inflammation and fat necrosis to predominant fibrosis. This may explain the varied descriptive terms used in the literature to describe this entity.

HISTOLOGICAL TYPES CHARACTERIZATION

General
Combination of 3 features:
Fat necrosis
Chronic inflammatory infiltrate
Collagen deposition

In the early stage when fat necrosis predominates with little or no fibrosis, the diagnosis of mesenteric lipodystrophy has been used

Later, when fat necrosis subsides and chronic inflammation becomes predominant, may be designated mesenteric panniculitis

Finally, when fibrosis becomes the main feature, sclerosing or retractile mesenteritis have been used

SPECIAL STAINS/IMMUNOHISTOCHEMISTRY CHARACTERIZATION

BETA-CATENIN

beta-Catenin Immunohistochemistry Separates Mesenteric Fibromatosis From Gastrointestinal Stromal Tumor and Sclerosing Mesenteritis.

Montgomery E, Torbenson MS, Kaushal M, Fisher C, Abraham SC.
Am J Surg Pathol 2002 Oct;26(10):1296-301 Abstract quote
Although separating gastrointestinal stromal tumor (GIST) from mesenteric fibromatosis and sclerosing mesenteritis is clinically important, this distinction sometimes poses problems for practicing pathologists. In the STI571 (Gleevec, Imatinib) era, the problem may be further compounded when protocol-driven staining for CD117 (c-kit) is performed on spindle cell proliferations presenting in the bowel wall and mesentery using an antibody known to react with the majority of mesenteric fibromatoses when other antibodies are more specific.

Because most mesenteric fibromatoses have mutations in the pathway and hence have abnormal nuclear accumulation of beta-catenin protein, we studied beta-catenin expression among a panel of other immunohistochemical stains to distinguish mesenteric fibromatosis, GIST, and sclerosing mesenteritis. Examples of gastrointestinal stromal tumors (GIST, 11), sclerosing mesenteritis (5), and mesenteric fibromatosis (10) were retrieved from the archives of our institutions.

Cases were studied with an immunohistochemical panel consisting of CD117, beta-catenin, CD34, smooth muscle actin, desmin, keratin, and S-100 protein. Cases were scored as "negative," "focally positive," or "diffusely positive." In evaluating beta-catenin, nuclear accumulation was required. GIST all had CD117 (11 of 11, diffuse) and CD34 (11 of 11, diffuse) with variable actin (5 of 11, focal) and negative desmin, keratin, S-100 protein. All GIST lacked beta-catenin (0 of 11). Mesenteric fibromatosis had CD117 (6 of 10, 3 focal, 3 diffuse), typically expressed more weakly than in GIST, actin (5 of 9, focal), and desmin (3 of 8, focal) in keeping with myofibroblastic differentiation but lacked CD34, S-100, and keratin. CD117 staining was not eliminated by use of a non-avidin-biotin technique. Nuclear beta-catenin was detected in 9 of 10 fibromatoses, including one case associated with familial adenomatous polyposis. Two of five sclerosing mesenteritis cases focally expressed CD117. None of the sclerosing mesenteritis cases had nuclear beta-catenin. Sclerosing mesenteritis cases were otherwise fibroblastic and myofibroblastic with focal actin in 5 of 5 and negative desmin, keratin, and S-100 protein but one had CD34 (1 of 5, focal).

With increasing protocol-driven interest in evaluating bowel wall and mesenteric spindle cell lesions using CD117 (c-kit) antibodies, it is important for practicing pathologists to be aware that lesions other than GISTs are likely to express this antigen using certain antibodies. beta-Catenin staining identifies lesions that are, instead, mesenteric fibromatoses.

PROGNOSIS AND TREATMENT CHARACTERIZATION

Prognostic Factors
Ann Intern Med 1974;80:582–588.
Am J Surg Pathol 1997;21:392–398.

Prognosis is excellent

No patients died solely from the effects of sclerosing mesenteritis

TREATMENT
Ann Surg 1998;64:768–771

Proper treatment for sclerosing mesenteritis should be based on the stage of the disease

Early stage when fat necrosis predominates, many physicians tend not to treat because the disease process may regress spontaneously

When chronic inflammation becomes a prominent feature but fibrosis is not yet fully developed, medical treatment with corticosteroids, immunosuppressants, or progesterone may be beneficial in the prevention of disease progression

Finally, when fibrosis becomes extensive, especially when the disease presents as a large fibrotic mass with bowel obstruction, surgical interventions may be the best choice

MEDICAL

Sclerosing mesenteritis. Response to cyclophosphamide.

Bush RW, Hammar SP Jr, Rudolph RH.
Arch Intern Med 1986 Mar;146(3):503-5 Abstract quote
We present two patients with an aggressive form of sclerosing mesenteritis characterized by a progressive, life-threatening course, prominent retroperitoneal disease, and tubuloreticular structures in one case, an ultrastructural feature associated with autoimmune and cyclophosphamide-responsive diseases. In both patients, aggressive immunosuppressive medical therapy with cyclophosphamide resulted in prompt, dramatic improvement, without recurrence.

When the diagnosis of sclerosing mesenteritis is established, we recommend early aggressive medical therapy with cyclophosphamide, particularly when tubuloreticular structures are present.

Demonstration of efficacy of combining corticosteroids and colchicine in two patients with idiopathic sclerosing mesenteritis.

Genereau T, Bellin MF, Wechsler B, Le TH, Bellanger J, Grellet J, Godeau P.

Department of Internal Medicine, Groupe Hospitalier Pitie-Salpetriere, Paris, France.
Dig Dis Sci 1996 Apr;41(4):684-8 Abstract quote
Sclerosing mesenteritis is an uncommon condition of unknown etiology. It is likely to be the fibrous evolution of mesenteric panniculitis. It often has an indolent course but may be complicated by progressive bowel obstruction. The treatment of the symptomatic forms is not well established.

The observations of two women (20 and 65 years old) with a relentless downhill course of biopsy-proved sclerosing mesenteritis are described. A treatment regimen with corticosteroid therapy (initially 1 mg/kg/day) and colchicine (1 mg/day) led, in both cases, to a rapid improvement. Abdominal computer tomography showed reduction in the tumor size.

The combination of corticosteroids and colchicine is helpful in the management of symptomatic sclerosing mesenteritis. Follow-up with abdominal computed tomography is useful in evaluating the therapeutic impact.

Successful treatment of retractile mesenteritis with oral progesterone Gastroenterology 1998;114:1313–1317

Treatment of sclerosing mesenteritis with corticosteroids and azathioprine.

Bala A, Coderre SP, Johnson DR, Nayak V.

Division of Gastroenterology, Peter Lougheed Hospital, University of Calgary, Calgary, Canada.
Can J Gastroenterol 2001 Aug;15(8):533-5 Abstract quote
Sclerosing (idiopathic) mesenteritis is a rare disease that may present with abdominal pain or bowel obstruction. A 21-year-old man was diagnosed with sclerosing mesenteritis, and treated with a partial ileal resection and defunctioning ileostomy. He was subsequently started on corticosteroids and azathioprine. Five months later, at the time of ileostomy reversal, he was disease-free.

The diagnosis and management of this disease are discussed.

Sternberg S. Diagnostic Surgical Pathology. Third Edition. Lipincott Williams and Wilkins 1999.

Commonly Used Terms

Gastrointestinal Tract

Last Updated 10/23/2002

DISEASE ASSOCIATIONS	CHARACTERIZATION
MULTIFOCAL OR SYSTEMIC FIBROSCLEROSIS	Semin Diagn Pathol 1998;15:161–173 Disease spectrum that also includes retroperitoneal fibrosis, sclerosing mediastinitis, Riedel thyroiditis, and orbital pseudotumor
HIV
Sclerosing mesenteritis: an unusual cause of abdominal pain in an HIV-positive patient. Venkataramani A, Behling CA, Lyche KD. Department of Medicine, University of California, San Diego 92103-8413, USA.	Am J Gastroenterol 1997 Jun;92(6):1059-60 Abstract quote Sclerosing mesenteritis is a rare, idiopathic, and benign mesenteric lesion that is characterized by fat necrosis, fibrosis, and chronic inflammation. We report a case of sclerosing mesenteritis presenting as recurrent abdominal pain in an HIV-positive patient. Because of the wider differential diagnosis in such cases, the patient underwent an extensive workup culminating in a laparoscopy with biopsy. Tamoxifen has been shown to be useful in the treatment of desmoid tumors and idiopathic retroperitoneal fibrosis. We present the first case of sclerosing mesenteritis to respond to tamoxifen therapy. Because this drug is relatively safe and simple to dose, its utility as therapy for patients with this benign but debilitating disease should be considered.
INFLAMMATORY PSEUDOTUMOR
Concomitant sclerosing mesenteritis and inflammatory pseudotumor simulating gastric lymphoma or linitis plastica. Gincherman Y, Langer JE, Miller L. Department of Surgery, Hospital of the University of Pennsylvania, University of Pennsylvania School of Medicine, Philadelphia, USA.	J Surg Oncol 1995 Jun;59(2):136-8 Abstract quote Both inflammatory pseudotumors and sclerosing (retractile) mesenteritis are uncommon conditions of unknown origin. A number of authors have reported patients presenting with complaints that were attributed to one or the other of these entities. In our review of the literature, we were unable to find a single case report of mixed abdominal findings that could be explained by the presence of both conditions. We report a case of the patient presenting with abdominal mass that was identified as having features of both sclerosing mesenteritis and inflammatory pseudotumor on pathologic diagnosis.
NEPHROPATHY
Minimal change nephropathy associated with sclerosing mesenteritis. Vernace MA, Bellucci AG, Mossey RT, Susin M, Mailloux LU, Wilkes BM, Katz S, Eskreis D. Department of Medicine, North Shore University Hospital, Manhasset, NY 11030, USA.	Nephron 1996;73(3):473-6 Abstract quote A 65-year-old man with sclerosing mesenteritis developed the nephrotic syndrome. Percutaneous renal biopsy revealed classical histologic findings of minimal change nephropathy with a mild interstitial nephritis. Immunomodulation with prednisone led to a rapid and complete remission of the proteinuria but did not alter the course of the underlying sclerosing mesenteritis. The association of lymphomatous and nonlymphomatous neoplasms with minimal change nephropathy has been well-described. Our review of the literature indicates a parallel association of malignant lymphoma with sclerosing mesenteritis and a variety of disorders that constitute a spectrum of disease. The occurrence of this histopathologic form of renal injury and therapeutic response in the setting of a known lymphoreticular disorder suggests a role for a generalized alteration in cell-mediated immunity and not a tumor-induced elaboration of a factor(s) that directly damages the glomerular filtration barrier.
PROTEIN LOSING ENTEROPATHY
Protein-losing enteropathy: first manifestation of sclerosing mesenteritis. Horing E, Hingerl T, Hens K, von Gaisberg U, Kieninger G. Department of Internal Medicine, Krankenhaus Bad Cannstatt, Stuttgart, Germany.	Eur J Gastroenterol Hepatol 1995 May;7(5):481-3 Abstract quote OBJECTIVE: To report the case of an unusual form of protein-losing enteropathy. PATIENT: A 54-year-old patient with hypoechoic tumours resembling lipomas in the mesentery. INTERVENTIONS: Following examination by ultrasound and computed tomography, the well-known intestinal and extra-intestinal forms of protein-losing enteropathy were excluded and a diagnostic laparotomy was performed. The whole mesentery was infiltrated by a large unresectable tumour. Histological examination showed that it was a sclerosing mesenteritis. MAIN OUTCOME MEASURES: Steroid therapy dramatically improved the protein-losing enteropathy. CONCLUSION: Pathogenically, the enteropathy may be interpreted as the result of disturbed lymphatic drainage caused by the sclerosed mesentery.

PROGNOSIS AND TREATMENT	CHARACTERIZATION
Prognostic Factors	Ann Intern Med 1974;80:582–588. Am J Surg Pathol 1997;21:392–398. Prognosis is excellent No patients died solely from the effects of sclerosing mesenteritis
TREATMENT	Ann Surg 1998;64:768–771 Proper treatment for sclerosing mesenteritis should be based on the stage of the disease Early stage when fat necrosis predominates, many physicians tend not to treat because the disease process may regress spontaneously When chronic inflammation becomes a prominent feature but fibrosis is not yet fully developed, medical treatment with corticosteroids, immunosuppressants, or progesterone may be beneficial in the prevention of disease progression Finally, when fibrosis becomes extensive, especially when the disease presents as a large fibrotic mass with bowel obstruction, surgical interventions may be the best choice
MEDICAL
Sclerosing mesenteritis. Response to cyclophosphamide. Bush RW, Hammar SP Jr, Rudolph RH.	Arch Intern Med 1986 Mar;146(3):503-5 Abstract quote We present two patients with an aggressive form of sclerosing mesenteritis characterized by a progressive, life-threatening course, prominent retroperitoneal disease, and tubuloreticular structures in one case, an ultrastructural feature associated with autoimmune and cyclophosphamide-responsive diseases. In both patients, aggressive immunosuppressive medical therapy with cyclophosphamide resulted in prompt, dramatic improvement, without recurrence. When the diagnosis of sclerosing mesenteritis is established, we recommend early aggressive medical therapy with cyclophosphamide, particularly when tubuloreticular structures are present.
Demonstration of efficacy of combining corticosteroids and colchicine in two patients with idiopathic sclerosing mesenteritis. Genereau T, Bellin MF, Wechsler B, Le TH, Bellanger J, Grellet J, Godeau P. Department of Internal Medicine, Groupe Hospitalier Pitie-Salpetriere, Paris, France.	Dig Dis Sci 1996 Apr;41(4):684-8 Abstract quote Sclerosing mesenteritis is an uncommon condition of unknown etiology. It is likely to be the fibrous evolution of mesenteric panniculitis. It often has an indolent course but may be complicated by progressive bowel obstruction. The treatment of the symptomatic forms is not well established. The observations of two women (20 and 65 years old) with a relentless downhill course of biopsy-proved sclerosing mesenteritis are described. A treatment regimen with corticosteroid therapy (initially 1 mg/kg/day) and colchicine (1 mg/day) led, in both cases, to a rapid improvement. Abdominal computer tomography showed reduction in the tumor size. The combination of corticosteroids and colchicine is helpful in the management of symptomatic sclerosing mesenteritis. Follow-up with abdominal computed tomography is useful in evaluating the therapeutic impact.
Successful treatment of retractile mesenteritis with oral progesterone	Gastroenterology 1998;114:1313–1317
Treatment of sclerosing mesenteritis with corticosteroids and azathioprine. Bala A, Coderre SP, Johnson DR, Nayak V. Division of Gastroenterology, Peter Lougheed Hospital, University of Calgary, Calgary, Canada.	Can J Gastroenterol 2001 Aug;15(8):533-5 Abstract quote Sclerosing (idiopathic) mesenteritis is a rare disease that may present with abdominal pain or bowel obstruction. A 21-year-old man was diagnosed with sclerosing mesenteritis, and treated with a partial ileal resection and defunctioning ileostomy. He was subsequently started on corticosteroids and azathioprine. Five months later, at the time of ileostomy reversal, he was disease-free. The diagnosis and management of this disease are discussed.

EPIDEMIOLOGY	CHARACTERIZATION
SYNONYMS	Mesenteric lipodystrophy Mesenteric panniculitis Retractile mesenteritis
AGE RANGE-MEDIAN	>50 years
SEX (M:F)	Males

GROSS APPEARANCE/CLINICAL VARIANTS	CHARACTERIZATION
General
VARIANTS
BILE DUCT
Concomitant sclerosing mesenteritis and bile duct fibrosis simulating Klatskin's tumor. Medina-Franco H, Listinsky C, Mel Wilcox C, Morgan D, Heslin MJ.	J Gastrointest Surg 2001 Nov-Dec;5(6):658-60 Abstract quote Sclerosing mesenteritis is an uncommon benign condition that should be included in the differential diagnosis of abdominal masses. We present the first reported case of this condition in association with idiopathic bile duct fibrosis simulating Klatskin's tumor. A review of the literature regarding both clinical entities is presented.
CALCIFICATIONS
Mesenteric lipodystrophy with fever of unknown origin and mesenteric calcifications	South Med J 1999;92:513–516.
PANCREAS
Sclerosing mesenteritis involving the pancreas: two cases of a rare cause of abdominal mass mimicking malignancy	Eur J Gastroenterol Hepatol 1999;11:1323–1329
Sclerosing mesenteritis seen clinically as pancreatic pseudotumor: two cases and a review. Sheikh RA, Prindiville TP, Arenson D, Ruebner BH. Department of Gastroenterology, University of California, Davis, USA.	Pancreas 1999 Apr;18(3):316-21 Abstract quote Sclerosing mesenteritis is an uncommon nonneoplastic inflammatory process in the mesentery that is seen as a pseudotumor, usually involving the small bowel mesentery, the mesenteric fat, and less commonly, the mesentery of the large bowel. We report two cases of sclerosing mesenteritis and review the literature on this rare disease. Both patients had pain, profound weight loss, and a mass on computed tomography (CT) scan of the abdomen. The provisional diagnosis was pancreatic neoplasm on the basis of clinical presentation and imaging studies. The diagnosis of sclerosing mesenteritis was established by histologic findings in biopsy material obtained at laparotomy in both cases. Interval histologic studies in one patient who had a high CA 19-9 level, progressive biliary ductal and partial duodenal compression, revealed a transitional histologic pattern from predominant inflammation and fat necrosis to predominant fibrosis. This may explain the varied descriptive terms used in the literature to describe this entity.