A58-year-old white female presented with an eight-month history of progressive lower abdominal pain and bloating. She experienced intermittent constipation followed by a five-month period of persistent loose, watery diarrhea, a 35-pound weight loss, fatigue, anorexia, and avoidance of food.
Her past medical and surgical history were significant for hypertension, depression, appendectomy, laparoscopic ovarian cystectomy (of benign histology), and cholelithiasis. Her medication list consisted of pindolol and sertraline. Her physical exam was remarkable for abdominal distention, palpable mass, fluid wave, shifting dullness, and hypoactive bowel sounds. There was no tenderness or organomegaly. She had a mild microcytic anemia with no leukocytosis. Liver chemistries and electrolytes were normal. The erythrocyte sedimentation rate was 51. The initial CT scan of the abdomen is shown at right. TH
What is the most likely differential diagnosis?
- Pneumatosis intestinalis;
- Ovarian carcinoma or peritoneal carcinomatosis;
- Sclerosing mesenteritis;
- Spontaneous bacterial peritonitis; or
The answer is C: sclerosing mesenteritis (SM). The CT scan shows a bulky heterogeneous mesenteric mass measuring approximately 8.7 x 6 x 10 cm, with a focal, 2-cm calcification at the lateral margin. The mass began at the proximal superior mesenteric artery, extended inferiorly to the top of the pelvis, and encased the body of the pancreas, central mesenteric vessels and the confluence of the portal, splenic, and superior mesenteric veins (SMV). The SMV was poorly visualized and may have been compressed or occluded by the mass. Diffuse abdominal and pelvic ascites also were seen.
Results of a needle biopsy of the mesenteric mass showed fibrous tissue and a mixed population of B cells and T cells consistent with sclerosing mesenteritis, a fibroinflammatory reactive process.
Sclerosing or retractile mesenteritis is an uncommon, idiopathic, nonneoplastic, tumor-like lesion that thickens and shortens the mesentery.1 The condition consists of a pathophysiological spectrum of disease, the classification of which is based on the predominant histological finding on tissue biopsy. Cases in which the predominant findings are fatty degeneration and necrosis are known as the mesenteric lipodystrophy variant; those in which chronic inflammation predominates are known as the mesenteric panniculitis variant; and finally, the predominantly fibrotic form is known as the retractile mesenteritis or mesenteric fibrosis variant.
The presence of some degree of fibrosis, chronic inflammation, and fat necrosis in all three lesions, as well as their common demographic and clinical characteristics, suggest that the three diagnostic groups represent a single clinical entity.2 Sclerosing mesenteritis is used as an umbrella term that encompasses all three histologic variants.
Numerous theories exist to explain the pathogenesis of the condition, most commonly relating to a non-specific reaction to mesenteric injuries such as antecedent surgery or abdominal trauma, or possibly autoimmunity, ischemia/infection, and or paraneoplastic phenomena.
A study of 68 cases of mesenteric panniculitis undertaken by Durst, et al., showed that the age range is diverse, affecting patients from seven to 82 years.3 In another study, Emory, et al., reported an average age of 60.1 years at presentation.2 In both studies there was a slight male preponderance, with a male: female ratio of 1.9:1, and 1.8:1.2,3
In the largest reported experience with patients with sclerosing mesenteritis from a single institution, the majority were male (72%) with an age range of 34-87 years.10,11 Of these patients, the most common presenting complaints are abdominal pain (36%-67%), vomiting (18%-32%), palpable abdominal mass (16%), anorexia (7%-17%), weight loss (14%-45%), constipation (8%-15%), diarrhea (7%-26%), and rectal bleeding (5%). The duration of symptoms varies from 24 hours to two years.3-10 In most cases, the blood chemistry and urinalysis were reported to be normal, although an elevated sedimentation rate has been reported in a minority.3,11
Diagnosis usually depends on imaging studies (most often CT scan) and pathological review of biopsy specimens. Concurrent pathology is found in 18%-25% of cases, including lymphoma (7%), cholelithiasis (4%), cirrhosis of the liver (3%), and abdominal aortic aneurysm (3%).3,10 Other conditions associated with idiopathic fibrosis, such as retroperitoneal fibrosis and sclerosing pancreatitis, have been reported to occur together with SM.4,10
To date, treatment options are guided by anecdotal experience and reports of open label clinical results.10,11 Clinical and experimental studies have suggested a possible hormonal influence on fibrous proliferation in retroperitoneal fibrosis, which led to the discovery of the beneficial effect of anti-estrogenic treatment with tamoxifen.5,6 Clark, et al., had noticed that tamoxifen was successfully used in the treatment of desmoid tumors and then reported its use in two cases of retroperitoneal fibrosis.5 Others have since used tamoxifen in sclerosing mesenteritis, including a relatively large experience from our institution that suggests the combination of tamoxifen with a prednisone taper may be the most beneficial treatment for this condition.7,10,11
Other treatments that have been reported to be of some benefit include combination of corticosteroids and colchicine or azathioprine, although these reports include very small numbers of patients.8,10 Ginsburg, et al., reported their experience with thalidomide in a short term, open-label study in five symptomatic subjects.12 Four patients (80%) experienced an improvement in symptoms, and one achieved complete remission by week four, which was sustained. There was also a decrease in inflammatory markers, although no changes were noted on follow-up CT scans.
The natural history of sclerosing mesenteritis is quite variable, with a few patients undergoing spontaneous remission, many experiencing an indolent course, and others progressing to bowel obstruction or other complications, including chylous ascites, mesenteric venous or arterial occlusion, and malnutrition (often resulting in the need for parenteral nutrition).10,11 There have been fatal cases of this condition reported in the literature; however, Durst, et al., found that of 40 patients undergoing exploratory laparotomy and biopsy, only one patient died as a direct result of the disease after 12 years and several explorations.9-11 In the remaining 39 patients, their symptoms resolved without any further treatment, although in some the abdominal mass was persistently palpable.3. Similarly Emory, et al., found that after following 42 patients for an average of 9.5 years, only three patients had complications that resulted in death, all of which occurred in the postoperative period.2
In our experience, three of 92 patients (3%) died from causes that were thought to be attributable to sclerosing mesenteritis or its treatment.10,11
In summary, sclerosing mesenteritis is a rare disease entity that thickens and shortens the mesentery due to a non-specific fibroinflammatory reaction in the mesentery. Diagnosis relies on CT scanning and tissue biopsy, which shows variable degrees of fibrosis, chronic inflammation, and fat necrosis. Treatment options are based on anecdotal experience only. Tamoxifen, with or without combination therapy with prednisone, colchicine, azathioprine, and thalidomide, appears to be of some benefit. Prognosis is variable, with some patients achieving remission while others die from complications related to disease progression such as bowel obstruction, mesenteric vascular occlusion, and malnutrition; however, many have persistent symptoms that may improve but not resolve with medical therapy. TH
- Kelly JK, Hwang WS. Idiopathic retractile (sclerosing) mesenteritis and its differential diagnosis. Am J Surg Pathol. 1989;13(6):513-521.
- Emory TS, Monihan JM, Carr NJ, et al. Sclerosing mesenteritis, mesenteric panniculitis and mesenteric lipodystrophy: a single entity? Am J Surg Pathol. 1997 Apr;21(4):392.
- Durst AL, Freund H, Rosenmann E, et al. Mesenteric panniculitis: review of the literature and presentation of cases. Surgery. 1977;81:203.
- Chew CK, Jarzylo SV, Valberg LS. Idiopathic retroperitoneal fibrosis with protein-losing enteropathy and duodenal obstruction successfully treated with corticosteroids. Can Med Assoc J. 1966;95(23):1183-1188.
- Clark CP, Vanderpool D, Preskitt JT. The response of retroperitoneal fibrosis to tamoxifen. Surgery. 1991 Apr;109(4):502-506.
- Owens LV, Cance WG, Huth JF. Retroperitoneal fibrosis treated with tamoxifen. Am Surg. 1995;61:842-844.
- Venkataramani A, Behling CA, Lynche KD. Sclerosing mesenteritis: an unusual cause of abdominal pain in an HIV-positive patient. Am J Gastroenterol. 1997 Jun;92(6):1059-1060.
- Genereau T, Bellin MF, Wechsler B. Demonstration of efficacy of combining corticosteroids and colchicine in two patients with idiopathic sclerosing mesenteritis. Dig Dis Sci. 1996;41(4):684-688.
- Andersen JA, Rasmussen NR, Pedersen JK. Mesenteric panniculitis: a fatal case. Am J Gastroenterol. 1982 Jul;77(7):523-525.
- Akram S, Pardi DS, Smyrk TC. Sclerosing mesenteritis: The Mayo Clinic Experience. (Clinical features and tx response) Gastroenterology. 2003;A-190.
- Akram S, Pardi DS, Smyrk TC. Effect of tamoxifen on clinical course of sclerosing mesenteritis. Gastroenterology. 2006;130:A-322.
- Ginsburg PM, Ehrenpreis ED. A pilot study of thalidomide for patients with symptomatic mesenteric panniculitis. Aliment Pharmacol Ther. 2002 Dec;16(12):2115-2122.