Sclerosing Mesenteritis

Fibrotic phenotype of IgG4-related disease

A prompt response to glucocorticoids is a clinical hallmark of IgG4-related disease. However, manifestations characterised by prominent tissue fibrosis on histological examination can be less responsive to glucocorticoid therapy than other types of IgG4-related disease. These manifestations include retroperitoneal fibrosis, fibrosing mediastinitis, Riedel thyroiditis, orbital pseudotumor, and hypertrophic pachymeningitis, among others. To explain this discrepancy, a preliminary distinction into proliferative and fibrotic phenotypes of IgG4-related disease has been proposed on the basis of clinical presentation, pathological features, and response to immunosuppressive therapy. Implications of this classification for patient management remain an important area of investigation. In this Series paper, we aim to dissect the pathophysiology of tissue fibrosis in IgG4-related disease and discuss how clinicians should approach the management of fibrotic manifestations of IgG4-related disease based on the most recent diagnostic and therapeutic developments.

Sclerosing Mesenteritis: A Concise Clinical Review for Clinicians

Sclerosing mesenteritis (SM), an idiopathic nonneoplastic condition affecting 0.18% to 3.14% of the population, is characterized by chronic fat necrosis, inflammation, and fibrosis most commonly of the mesentery of the small intestine. Sclerosing mesenteritis typically presents in the fifth or sixth decade of life, where patients with a history of abdominal surgery and/or autoimmune disease may be at higher risk. While many patients are asymptomatic, clinical features and complications are related to the mass effect resulting from the inflammation and fibrosis involved in the pathogenesis of SM. When present, common signs, symptoms, and complications include abdominal pain, weight loss, diarrhea, palpable abdominal mass on examination, bowel obstruction, chylous ascites, and mesenteric vessel thrombosis. Although SM was historically diagnosed predominantly by biopsy, current practice has shifted away from this to computed tomography imaging of the abdomen, given the invasive nature of biopsy. However, certain conditions, including mesenteric neoplasia (lymphoma, metastatic carcinoid tumor, desmoid tumor, mesenteric carcinomatosis), can mimic SM on imaging, and if clinical suspicion is equivocal, a biopsy may be warranted for definitive diagnosis. Asymptomatic patients do not require treatment. For patients with pronounced symptoms or complicated SM, the combination of tamoxifen 10 mg twice daily and prednisone 40 mg daily is the first-line pharmacotherapy; no randomized controlled trial of this regimen has been performed. Rarely, surgery may be necessary in cases of persistent bowel obstruction refractory to medical management. Sclerosing mesenteritis has an overall benign course in most cases, but disease progression and fatal outcomes have been reported.

A review of 17 cases of mesenteric panniculitis in Zhengzhou Ninth People's Hospital in China

PURPOSE

Mesenteric panniculitis (MP) represents the uncommon, benign and chronic inflammatory disorder affecting the mesenteric adipose tissues. Its etiology, diagnosis and treatment remain unnoticed. Our report focused on shedding more lights on this condition.

PATIENTS AND METHODS

Seventeen MP patients were identified by searching the electronic medical record system in the Zhengzhou Ninth People's Hospital using the search terms "Mesenteric panniculitis" from October 2015 to March 2023. All cases were diagnosed with MP through computed tomography (CT). Their clinical features and treatments were analyzed.

RESULTS

There were altogether 17 cases enrolled for this analysis. The male to female ratio was 8:9, and the median age at diagnosis was 64 (range: 37-96) years. There were 15 patients (88.2%) showing abdominal pain to varying degrees. The proportions of symptoms of nausea, vomiting and fever were 23.5%, 23.5% and 41.2%, respectively. Neoplastic disease was present in 3 patients (17.6%). Meanwhile, 9 patients (52.9%) had gallstones, 3 (17.6%) had cholecystitis and 1 (5.9%) had gallbladder polyps. Six patients (35.3%) received antibiotics treatment only and 1 (5.9%) received oral antibiotics and prednisone. One patient (5.9%) received antibiotics followed by prednisone treatment, because the symptoms were significantly relieved after antibiotic treatment, while the disease recurred soon after, and the symptoms improved again after prednisone treatment. The abdominal pain in 9 patients (52.9%) was relieved spontaneously. Two patients (11.8%) died, including one due to respiratory failure caused by pneumonia and the other one because of pancreatic cancer with lung and liver metastases.

CONCLUSION

MP is a poorly understood chronic inflammatory disease. Patients often have abdominal pain as the main symptom, accompanied by comorbidities in the gallbladder, and the prognosis is usually good after correct diagnosis and treatment, Therefore, the present report aims to promote the awareness among clinicians of patients with non-classic abdominal symptoms, so as to avoid misdiagnosis or missed diagnosis.

An Uncommon Expression of Immunoglobulin G4 (IgG4)-Related Disease: Sclerosing Mesenteritis Concomitant With IgG4-Related Autoimmune Pancreatitis

A 63-year-old male presented to our oncological hospital with a one-year evolving abdominal pain, with an abdominal mass feeling. Contrast-enhanced computed tomography displayed two soft tissue masses, one at the mesentery root and the second around the pancreatic tail; at the same time the patient presented with hyperlipasemia. Endoscopic biopsy for the pancreatic mass and surgical biopsy of the mesenteric one were performed in order to narrow diagnosis. No neoplastic cells but only dense fibro-inflammatory changes with immunoglobulin G4 (IgG4)-positive plasma cell inclusions were observed for both biopsies. A diagnostic and therapeutic strategy based on high suspicion of IgG4-related disease was adopted, with good clinical and imaging response to corticotherapy.

Sclerosing mesenteritis following immune checkpoint inhibitor therapy

PURPOSE

Sclerosing mesenteritis (SM), a fibroinflammatory process of the mesentery, can rarely occur after immune checkpoint inhibitor (ICI) therapy; however, its clinical significance and optimal management are unclear. We aimed to assess the characteristics and disease course of patients who developed SM following ICI therapy at a single tertiary cancer center.

METHODS

We retrospectively identified 12 eligible adult cancer patients between 05/2011 and 05/2022. Patients' clinical data were evaluated and summarized.

RESULTS

The median patient age was 71.5 years. The most common cancer types were gastrointestinal, hematologic, and skin. Eight patients (67%) received anti-PD-1/L1 monotherapy, 2 (17%) received anti-CTLA-4 monotherapy, and 2 (17%) received combination therapy. SM occurred after a median duration of 8.6 months from the first ICI dose. Most patients (75%) were asymptomatic on diagnosis. Three patients (25%) reported abdominal pain, nausea, and fever and received inpatient care and corticosteroid treatment with symptom resolution. No patients experienced SM recurrence after the completion of corticosteroids. Seven patients (58%) experienced resolution of SM on imaging. Seven patients (58%) resumed ICI therapy after the diagnosis of SM.

CONCLUSIONS

SM represents an immune-related adverse event that may occur after initiation of ICI therapy. The clinical significance and optimal management of SM following ICI therapy remains uncertain. While most cases were asymptomatic and did not require active management or ICI termination, medical intervention was needed in select symptomatic cases. Further large-scale studies are needed to clarify the association of SM with ICI therapy.

Fatal sclerosing mesenteritis: a 7-year-old male autopsy case report

Sclerosing Mesenteritis (SM) is a rare diagnosis, particularly in pediatric patients, and is typically non-fatal when appropriately treated. Although molecular and immunohistochemical alterations have been described, no pathognomonic signature has been identified for this entity. This report presents a case of a seven-year-old boy who suffered sudden cardiorespiratory arrest. Upon autopsy, he was found to have multicentric SM on the upper mesentery, which led to bowel wall thinning and abdominal bleeding with bacterial translocation. We performed comprehensive morphological, immunohistochemical, and molecular analyses. SM is an atypical disorder with diverse clinical manifestations, including a rare but potentially fatal course. Early diagnosis is critical, given its potential severity. To our knowledge, this is the first case report of pediatric mortality linked to SM. Our findings emphasize the importance of increased awareness and early detection of SM in pediatric patients.

Idiopathic sclerosing mesenteritis presenting with small bowel volvulus in a patient with antiphospholipid syndrome: A case report

BACKGROUND

Sclerosing mesenteritis is a rare disorder involving inflammation of the mesentery. Its etiology remains unclear, but it is believed to be associated with previous abdominal surgery, trauma, autoimmune disorders, infection, or malignancy. Clinical manifestations of sclerosing mesenteritis are varied and include chronic abdominal pain, bloating, diarrhea, weight loss, formation of an intra-abdominal mass, bowel obstruction, and chylous ascites. Here, we present a case of idiopathic sclerosing mesenteritis with small bowel volvulus in a patient with antiphospholipid syndrome.

CASE SUMMARY

A 68-year-old female presented with recurrent small bowel obstruction. Imaging and pathological findings were consistent with sclerosing mesenteritis causing mesenteric and small bowel volvulus. Computed tomography scans also revealed pulmonary embolism, and the patient was started on a high dose of corticosteroid and a therapeutic dose of anticoagulants. The patient subsequently improved clinically and was discharged. The patient was also diagnosed with antiphospholipid syndrome after a hematological workup.

CONCLUSION

Sclerosing mesenteritis is a rare condition, and patients with no clear etiology should be considered for treatment with immunosuppressive therapy.

Goiter and Abdominal Mass: A Rare Presentation of Riedel's Thyroiditis

Riedel's thyroiditis (RT) is a rare inflammatory autoimmune disease, often associated with various forms of systemic fibrosis such as sclerosing mesenteritis (SM). A woman in her late 30s presented with a diffusely enlarged firm goiter and a mesenteric mass complicated by biliary obstruction and hydronephrosis. Labs and thyroid ultrasound were consistent with autoimmune thyroiditis. Abdominal imaging demonstrated a mesenteric mass that encased mesenteric vessels and ureter. Flow cytometry and infectious workup were negative. Both thyroid and mesenteric biopsies revealed dense fibrosis with patchy lymphoplasmacytic aggregates, no evidence of carcinoma, lymphoma, or IgG4-related disease, which confirmed diagnoses of RT and SM. She improved clinically with steroids. The coincidental timing of thyroid enlargement and the mesenteric mass, and the similarity in histology suggest an association between RT and SM. Overall, the case highlights the challenges in diagnosing RT given its rarity and emphasises the importance of early treatment to prevent systemic involvement.

Measurement of the stiffness of the normal terminal ileum mesentery using shear-wave elastography

OBJECTIVE

To investigate the feasibility of using shear-wave elastography (SWE) to measure the stiffness of the normal terminal ileum mesentery, and to establish its normal reference range.

METHODS

Ninety-five normal subjects and 22 patients with mesentery-related disease were included. The average Young's modulus of the normal terminal ileal mesentery was measured by SWE ultrasound. The thickness and the extent to which mesenteric fat extended around the intestinal circumference of the normal terminal ileum were also recorded. The normal reference range was established and the SWE values of normal and diseased subjects were compared.

RESULTS

Transabdominal SWE examination of the terminal ileum mesentery was successfully performed on 91 subjects (95.8 %). The mean extent range, thickness, and SWE value of the normal terminal ileum mesentery were 1/4 (1/5-1/3), 6.8 ± 2.4 mm, and 4.3 ± 2.1 kPa, respectively. These parameters did not differ significantly between genders, and across age and body mass index groups (all P > 0.05). The intra- and inter-operator consistencies were excellent for the replicated SWE measurements (0.801 [95 % confidence interval: 0.560-0.916] and 0.751 (95 % confidence interval: 0.388-0.900], respectively). The mean mesenteric elasticity in diseased subjects was 21.9 ± 10.7 kPa, which was significantly higher than that in normal subjects (P < 0.001). The cut-off value for mesenteric elasticity was 9.3 kPa, with a sensitivity of 90 % and a specificity of 100 % (P < 0.001).

CONCLUSION

SWE can be used to reliably evaluate the stiffness of the terminal ileum mesentery in normal subjects.

Sclerosing Mesenteritis Managed Conservatively With Prednisone

The authors present the case of a middle-aged lady with two weeks of abdominal pain. Computed tomography imaging revealed sclerosing mesenteritis. Sclerosing mesenteritis is also known as mesenteric panniculitis and is a chronic fibrosing inflammatory disease that primarily affects the adipose tissue of the mesentery in the small intestine and colon. The clinical presentation, imaging findings, differential diagnosis, and therapeutic management are presented in this report. In our patient's case, she was able to be managed conservatively, without the need for surgery. This reflects the most benign and self-limiting natural history of the disease.

Successful treatment of sclerosing mesenteritis with tamoxifen monotherapy

Sclerosing mesenteritis is a rare disorder characterized by fat necrosis, chronic inflammation, and fibrosis of the small bowel mesentery. With a paucity of published clinical trials on sclerosing mesenteritis, treatment is based on case reports and trials of other fibrosing diseases, such as idiopathic retroperitoneal fibrosis. We present a case of a 68-year-old woman with sclerosing mesenteritis who exhibited complete symptomatic and radiographic resolution with the use of tamoxifen monotherapy.

Mesenteric panniculitis is associated with cardiovascular risk-factors: A case-control study

BACKGROUND

This study evaluated the prevalence of cardiovascular risk-factors in patients with mesenteric panniculitis.

AIMS

To determine whether cardiovascular risk-factors and mesenteric panniculitis are associated.

METHODS

Retrospective, matched case-control study of patients referred to Meir Medical Center, Israel, 2014-2019, who underwent computerized tomography scan, were diagnosed mesenteric panniculitis by radiologic criteria. They were compared to two, matched case-control groups: hospitalized patients without mesenteric panniculitis and the general population based on Israeli Ministry of Health surveys. Patients with active malignancy, IBD or significant intra-abdominal morbidity were excluded.

RESULTS

Of 376 patients with mesenteric panniculitis diagnosed by computerized tomography, 187 were included. Compared to hospital patients, they had higher incidence of dyslipidemia (77.5%/56.7%), hypertension (52.4%/40.6%), obesity (body mass index>30) (60.4%/30.5%) and nonalcoholic fatty liver disease (42.2%/16.6%). Similar differences were observed compared to the general population. In multivariable logistic regression, dyslipidemia, obesity, and nonalcoholic fatty liver disease were independent predictors for mesenteric panniculitis.

CONCLUSIONS

Patients with mesenteric panniculitis have more cardiovascular risk-factors compared to a case-control group and to the general population. This suggests that mesenteric panniculitis is clinically significant and may be part of the metabolic morbidity burden. This association should be further explored.

Sclerosing mesenteritis due to Mycobacterium genavense infection: A case report

RATIONALE

Since its first identification in the early 1990s, Mycobacterium genavense has been considered and opportunistic pathogen. It mainly causes gastrointestinal symptoms, but also disseminated infections in severely immunosuppressed patients. Sclerosing mesenteritis is a long-term complication with high morbidity and mortality. As it is a rare condition, there are no specific guidelines for its management. We report a challenging case of persistent M. genavense infection, and propose surgery as an alternative treatment strategy.

PATIENT CONCERNS

A 38-year-old Caucasian man presented to the emergency room with fever, abdominal pain, and night sweats for 3 months. HIV screening revealed a previously unknown HIV-1 infection, with a CD4 cell count of 216 cell/µL and viral load of 361.000 copies/mL at diagnosis. A body CT-scan showed mild splenomegaly as well as mesenteric and retroperitoneal enlarged lymph nodes. Fine needle aspiration revealed the presence of acid-fast bacilli, but mycobacterial cultures were negative. In the second sample, 16S RNA sequencing yielded a diagnosis of M. genavense infection. Despite 2 years of corticosteroids and antimycobacterial treatment excluding rifampicin due to a severe cutaneous reaction, there was no clinical improvement and an increase in the mesenteric lymph node size was observed, with a sclerosing transformation of the mesentery. A surgical approach was proposed to release small bowel loops and to remove fibrin. A second surgery was required due to an acute peritonitis ought to yeyunal segmental isquemia and perforation. Finally, the patient evolved favorably, and antimycobacterial drugs were suspended without relapse.

LESSONS

Despite a prolonged multidrug strategy, some patients develop persistent M. genavense infection. Once sclerosing mesenteritis is established, clinicians have few treatment options. Surgery should be considered in patients with sclerosing mesenteritis or bowel obstruction. The combination of medical and surgical treatment could be a potential cure for these patients.

Colchicine as an Alternative First-Line Treatment of Sclerosing Mesenteritis: A Retrospective Study

BACKGROUND

Sclerosing mesenteritis is a rare condition characterized by chronic inflammation and fibrotic changes of the mesentery.

AIMS

To determine the long-term management and outcomes of patients with sclerosing mesenteritis.

METHODS

Patients with biopsy-proven sclerosing mesenteritis at the Mayo Clinic between January 2006 and December 2016 were identified. Clinical data were collected retrospectively.

RESULTS

One hundred and three patients were identified, median age 68.0 years (range 35.0-85.3). Most patients were symptomatic (87.4%) at presentation. Patients received no treatment (52.4%), medical therapy (42.7%) or surgery (4.9%) on initial diagnosis. The most common initial regimens were prednisone plus tamoxifen (41.9%), prednisone alone (23.3%), and prednisone plus colchicine (11.6%) with 55.6%, 57.2%, and 60% of patients improving, respectively, p = 0.85 for a difference in response rates. At least half of the patients responded to prednisone plus tamoxifen, prednisone plus colchicine, or prednisone alone at 6.0, 7.2, and 8.4 months, respectively. At a median follow-up of 45.6 months (95% CI 24.1-69.7), 65.4% of patients were receiving medical therapy. Of those receiving tamoxifen-based, steroid-based, or steroid-sparing regimens, 100%, 87.5%, and 77.8% had improved by their last follow-up appointment respectively, p = 0.15.

CONCLUSION

Prednisone plus colchicine has a similar efficacy to prednisone plus tamoxifen for the initial and long-term treatment of sclerosing mesenteritis. The majority of patients were initiated on medical therapy over the long term with most reporting symptomatic improvement within a year. Death from SM was rare.

Sclerosing Mesenteritis Complicated With Mesenteric Lymphoma Responsive to Ustekinumab

A 45-year-old man with a 10-year history of biopsy-proven, steroid-dependent sclerosing mesenteritis failed/was intolerant to tamoxifen, azathioprine, colchicine, cyclophosphamide, and methotrexate. He developed osteoporosis, diabetes, and bilateral cataracts. He responded to infliximab but was diagnosed with mesenteric large B-cell lymphoma 6 months after treatment initiation. He achieved remission from lymphoma after chemotherapy, but the sclerosing mesenteritis remained poorly controlled. He was treated with ustekinumab (520 mg intravenously followed by 90 mg subcutaneously every 8 weeks), leading to complete steroid-free remission. He remains symptom and cancer-free 24 months after starting ustekinumab.

Mesenteric panniculitis does not confer an increased risk for cancers: A systematic review and meta-analysis

BACKGROUND

Mesenteric panniculitis (MP) is a non-specific, localized inflammation at the mesentery of small intestines which often gets detected on computed tomography. An association with malignant neoplasms remains unclear. We performed a systematic review and meta-analysis to examine the association of malignancy with MP.

METHODS

MEDLINE, EMBASE, Web of Science, and Cochrane databases were searched for articles published from inception to 2020 that evaluated the association of malignant neoplasms with MP in comparison with control groups. Using random-effects method, a summary odds ratio (OR) estimate with 95% confidence intervals for malignant neoplasms in MP was estimated.

RESULTS

Four case-control studies reporting data on 415 MP patients against 1132 matched-controls met inclusion criteria and were analyzed. The pooled OR for finding a malignant neoplasm in patients with MP was 0.907 (95% CI: 0.688-1.196; P = .489). The heterogeneity was mild and non-significant. Also, there was no heightened risk of any specific type of malignancy with MP. Three more case-series with unmatched-control groups (MP: 282, unmatched-controls: 17,691) were included in a separate analysis where the pooled OR of finding a malignant neoplasm was 2.963 (95% CI: 1.434-6.121; P = .003). There was substantial heterogeneity in this group.

CONCLUSION

This meta-analysis of matched controlled studies proves absence of any significant association of malignant neoplasms with MP. Our study also demonstrates that the putative association of malignancy with MP is mainly driven by uncontrolled studies or case-series.

IgG4-related diseases of the digestive tract

IgG4-related conditions affecting the digestive tract are part of a multi-organ fibro-inflammatory disorder termed IgG4-related disease (IgG4-RD), with autoimmune pancreatitis and IgG4-related cholangitis being the most prominent manifestations. Gastrointestinal symptoms include jaundice, weight loss, abdominal pain, biliary strictures, and pancreatic and hepatic masses that mimic malignant diseases. IgG4-RD manifestations occur less frequently elsewhere in the digestive tract, namely in the oesophagus, retroperitoneum or intestine. Evidence-based European guidelines frame the current state-of-the-art in the diagnosis and management of IgG4-related digestive tract disease. Diagnosis is based on histology (if available), imaging, serology, other organ involvement and response to therapy (HISORt criteria). Few biomarkers beyond serum IgG4 concentrations are reliable. The first-line therapy (glucocorticoids) is swiftly effective but disease flares are common at low doses or after tapering. Second-line therapy might consist of other immunosuppressive drugs such as thiopurines or rituximab. Further trials, for example, of anti-CD19 drugs, are ongoing. Although an association between IgG4-RD and the development of malignancies has been postulated, the true nature of this relationship remains uncertain at this time.

Diagnostic Performance of Point Shear Wave Elastography (pSWE) Using Acoustic Radiation Force Impulse (ARFI) Technology in Mesenteric Masses: A Feasibility Study

Purpose: To evaluate the diagnostic performance of ultrasound point shear wave elastography (pSWE) using acoustic radiation force impulse (ARFI) technology in different benign and malignant mesenteric masses (MMs). Methods: A total of 69 patients with MMs diagnosed from September 2018 to November 2021 were included retrospectively in the study. The inclusion criteria were (1) an MM over 1 cm; (2) valid ARFI measurements; and (3) confirmation of the diagnosis of an MM by histological examination and/or clinical and radiological follow-up. To examine the mean ARFI velocities (MAVs) for potential cut-off values between benign and malignant MMs, a receiver operating characteristics analysis was implemented. Results: In total, 37/69 of the MMs were benign (53.6%) and 32/69 malignant (46.4%). Benign MMs demonstrated significantly lower MAVs than mMMs (1.59 ± 0.93 vs. 2.76 ± 1.01 m/s; p < 0.001). Selecting 2.05 m/s as a cut-off value yielded a sensitivity and specificity of 75.0% and 70.3%, respectively, in diagnosing malignant MMs (area under the curve = 0.802, 95% confidence interval 0.699–0.904). Conclusion: ARFI elastography may represent an additional non-invasive tool for differentiating benign from malignant MMs. However, to validate the results of this study, further prospective randomized studies are required.

Sclerosing Mesenteritis, a Rare Cause of Mesenteric Mass in a Young Adult: A Case Report

Sclerosing mesenteritis (SM) is a rare fibroinflammatory disorder that involves mesenteric adipose tissue, more frequently localized in the small intestine, with an insidious clinical presentation having symptoms related to mass effect, usually resulting in bowel obstruction, mesenteric ischemia, as well as rapid weight loss. We report a case of a 23-year-old male presenting with palpable abdominal mass, mesogastric pain, and a history of rapid weight loss, who underwent exploratory laparoscopy. A hemorrhagic and gelatinous nodular tumor mass of the mesentery was identified and the surgical procedure was converted to a laparotomic approach. Histologically, the mass was composed of a proliferation of bland-looking spindle cells with slightly eosinophilic cytoplasm and elongated normochromatic nuclei with mild nuclear atypia, haphazardly set in a collagenized stroma; fat necrosis and inflammatory cells (lymphocytes, plasma-cells, and histiocytes) were also evident. The diagnosis of sclerosing mesenteritis was made. Our case emphasizes that histology remains pre-eminent for a correct diagnosis of SM, as pre-operative radiological-based diagnosis is non-specific.

[Motility disorder and weight loss in a 71-year-old male patient]

A 71-year-old man presented to this clinic for evaluation of an unclear abdominal tumor. He complained of abdominal pain, weight loss and motility disorders, which began some weeks previously. Ultrasound and computed tomography (CT) scans showed a large mesenterial space-occupying lesion with accompanying lymphadenopathy, slight accumulation of ascites and venous congestion. For confirmation of the suspected diagnosis of a sclerosing mesenteritis and exclusion of a lymphoma a laparoscopy was carried out with excision of tissue. The material was not adequately representative so that a laparotomy was carried out for removal of a new tissue specimen. The tissue specimen confirmed the rare diagnosis of sclerosing mesenteritis and due to the complaints a pharmaceutical treatment with prednisone and tamoxifen was initiated.

Ileal Neuroendocrine Tumor in a Patient with Sclerosing Mesenteritis: Which Came First?

BACKGROUND Jejunoileal neuroendocrine tumors (JI-NETs) are rare tumors that can be associated with mesenteric fibrosis. This case report is of an incidental finding of a JI-NET in a patient who was previously misdiagnosed with sclerosing mesenteritis. CASE REPORT A 42-year-old man was admitted to our institution with diffuse abdominal pain and clinical and radiographic signs of bowel obstruction. He had a previous diagnosis of sclerosing mesenteritis, which had been histologically diagnosed after an exploratory laparoscopy performed in 2009 for recurrent acute abdominal pain. He was also annually monitored through computed tomography scans for an incidentally discovered, gradually enlarging mesenteric mass for which a "wait and watch" management approach was adopted. After a period of fasting and observation, the patient underwent an urgent exploratory laparotomy because of his worsening condition. Intraoperatively, an ileocecal resection was performed, along with excision of the known mesenteric mass. The pathology report revealed an ileal NET with nodal metastases within the mesentery and mesenteric tumor deposits (pT3N1). CONCLUSIONS JI-NETs are rare entities, which are usually encountered as incidental findings or in patients with unspecific abdominal pain. Our case represents a probable delayed diagnosis of JI-NET in the context of sclerosing mesenteritis; therefore, a possible association between these 2 conditions should be investigated.

Peritoneal or mesenteric tumours revealing histiocytosis

Objective

Peritoneal or mesenteric tumours may correspond to several tumour types or tumour-like conditions, some of them being represented by histiocytosis. This rare condition often poses diagnostic difficulties that can lead to important time delay in targeted therapies. Our aim was to describe main features of histiocytoses with mesenteric localisation that can improve the diagnostic process.

Design

We performed a retrospective study on 22 patients, whose peritoneal/mesenteric biopsies were infiltrated by histiocytes.

Results

Abdominal pain was the revealing symptom in 10 cases, and 19 patients underwent surgical biopsies. The diagnosis of histiocytosis was proposed by initial pathologists in 41% of patients. The other initial diagnoses were inflammation (n=7), sclerosing mesenteritis (n=4) and liposarcoma (n=1). The CD163/CD68+CD1a- histiocytes infiltrated subserosa and/or deeper adipose tissues in 16 and 14 cases, respectively. A BRAF^V600E mutation was detected within the biopsies in 11 cases, and two others were MAP2K1 mutated. The final diagnosis was histiocytosis in 18 patients, 15 of whom had Erdheim-Chester disease. The median diagnostic delay of histiocytosis was 9 months. Patients treated with BRAF or MEK inhibitors showed a partial response or a stable disease. One patient died soon after surgery, and five died by the progression of the disease.

Conclusion

Diagnosis of masses arising in the mesentery should be carefully explored as one of the possibilities in histiocytosis. This diagnosis is frequently missed on mesenteric biopsies. Molecular biology for detecting the mutations in BRAF or in genes of the MAP kinase pathway is a critical diagnostic tool.

Magnetic Resonance Imaging, the Virtual Biopsy of Mesenteric Masses

ABSTRACT

The mesentery may be affected by multiple disease processes. Magnetic resonance imaging aids as a virtual pathological biopsy tool in the assessment of mesenteric masses because of superior soft tissue contrast and characterization. In this comprehensive review, we describe in detail the magnetic resonance imaging features of some solid and cystic mesenteric masses, with an emphasis on lesion-specific signal characteristics on T1- and T2-weighted images, diffusion-weighted imaging, and enhancement features on the dynamic postcontrast phase that aid in narrowing the differential diagnosis.

Ultrasonography-Based Management of Sclerosing Mesenteritis: From Diagnosis to Follow-Up

Sclerosing mesenteritis (SM) is an idiopathic disorder affecting mesentery, characterized by fat necrosis, chronic inflammation and fibrosis. The clinical presentation varies from asymptomatic cases to acute abdomen. The diagnosis is suggested by imaging but can be definitely established only by biopsies. In this paper, we discuss ultrasonography-based management of SM.

Debilitating Manifestation of a Disease with Multiple Names: A Severe Case of Sclerosing Mesenteritis

Sclerosing mesenteritis (SM) is a rare inflammatory condition with unknown etiology that affects the mesenteric adipose tissue. We present a case of a 49-year-old male with severe abdominal pain who underwent abdominal biopsy confirming the presence of adipose inflammation and necrosis. The diagnosis of SM was made, and the patient was treated with prednisone and tamoxifen. As this condition is rare, there are no standard guidelines for management. This case aims to outline a possible treatment plan.

Surgical Excision of Sclerosing Mesenteritis, Exploration of an Unknown Mesenteric Mass

Sclerosing mesenteritis is a rare and often benign condition characterized as a fibrotic disease consisting of non-suppurative inflammation of adipose tissue. Through mass effect, sclerosing mesenteritis can compromise the gastrointestinal lumen as well as mesenteric vessel integrity. There is a poor understanding of this disorder and its pathogenesis, which presents with various symptomatology and often without identification of inciting factors. Patients with sclerosing mesenteritis exhibit gastrointestinal and systemic manifestations including weight loss, fever, nausea, vomiting, diarrhea, and abdominal pain. This case presents a patient with a seven-month history of chronic, epigastric abdominal pain following laparoscopic surgery for acute uncomplicated appendicitis. The patient underwent work-up with computed tomography and magnetic resonance enterography that confirmed the presence of a mesenteric mass of unknown etiology located in the mid-epigastrium. Due to the inability to safely sample the mass, the patient underwent diagnostic laparoscopy, which was subsequently converted to an open procedure where excision of the mesenteric lesion was performed. Surgical pathology revealed fat necrosis with fibrosis, granulomatous inflammation, and dystrophic calcifications consistent with sclerosing mesenteritis. The patient was seen in follow-up with the resolution of her epigastric abdominal pain. This case report demonstrates a unique presentation of a symptomatic patient with a mesenteric mass not amenable to non-invasive biopsy. Complete excision of this lesser sac mass revealed sclerosis mesenteritis as the pathological cause.

Sclerosing Mesenteritis in a Patient Heterozygous for Factor V Leiden

Patient: Male, 33-year-old

Final Diagnosis: Sclerosing mesenteritis

Symptoms: Abdominal pain • diaphoresis • nausea • tachycardia

Medication:—

Clinical Procedure: Exploratory laparotomy

Specialty: Surgery