Adipokines from local fat cells shape the macrophage compartment of the creeping fat in Crohn's disease.

OBJECTIVE: The creeping fat in Crohn's disease (CD) is infiltrated by macrophages; local adipokine levels are increased. This study aimed to link these observations to define a role for macrophages in the pathology of human CD. METHODS: Human peripheral blood CD14 cells were polarised in vitro into M1 and M2 macrophages. The effects on adipokine receptors, phenotypic surface markers, cytokines and chemokines were assessed after treatment with leptin and adiponectin. Immunohistochemistry visualised macrophage subtypes in samples of mesenteric fat tissue from patients with CD. The chemotactic potential of secreted macrophage products was determined by T cell migration and chemokine production in vitro. RESULTS: Although both adipokines altered the phenotype and function of M1 and M2 macrophages, M2 macrophages were more susceptible. M1 responded to leptin by increased cytokine production, but the stronger effect was seen in M2 macrophages with high expression of interleukin (IL)-10, IL-6 and tumour necrosis factor α. Adiponectin exerted similar effects and led to upregulated mannose receptor expression by M2 macrophages. Large macrophage numbers within the mesenteric fat tissue of patients with CD comprise a unique infiltration predominantly of M2 macrophages, leading to an IL-10-rich environment. While leptin increased the potency of both subtypes to attract CD3 T cells, adiponectin only affected M2 macrophages. CONCLUSION: The adipocyte-dependent microenvironment within the creeping fat of patients with CD modulates the local macrophage compartment to a preference for the M2 subtype. The findings in this study with human cells suggest a protective role for the mesenteric fat in CD in terms of an enveloping barrier with the potential to limit intestinal inflammation.

Autoimmune Pancreatitis in Patients with Inflammatory Bowel Disease: A Real-World Multicentre Collaborative ECCO CONFER Study.

BACKGROUND: Autoimmune pancreatitis [AIP] is rarely associated with inflammatory bowel disease [IBD]. The long-term outcomes of AIP and IBD in patients with coexisting AIP-IBD and predictors of complicated AIP course have rarely been reported. METHODS: An ECCO COllaborative Network For Exceptionally Rare case reports project [ECCO-CONFER] collected cases of AIP diagnosed in patients with IBD. Complicated AIP was defined as a composite of endocrine and/or exocrine pancreatic insufficiency, and/or pancreatic cancer. We explored factors associated with complicated AIP in IBD. RESULTS: We included 96 patients [53% males, 79% ulcerative colitis, 72% type 2 AIP, age at AIP diagnosis 35 ±â€…16 years]. The majority of Crohn's disease [CD] cases [78%] had colonic/ileocolonic involvement. In 59%, IBD preceded AIP diagnosis, whereas 18% were diagnosed simultaneously. Advanced therapy to control IBD was used in 61% and 17% underwent IBD-related surgery. In total, 82% of patients were treated with steroids for AIP, the majority of whom [91%] responded to a single course of treatment. During a mean follow-up of 7 years, AIP complications occurred in 25/96 [26%] individuals. In a multivariate model, older age at AIP diagnosis was associated with a complicated AIP course (odds ratio [OR] = 1.05, p = 0.008), whereas family history of IBD [OR = 0.1, p = 0.03], and CD diagnosis [OR = 0.2, p = 0.04] decreased the risk of AIP complications. No IBD- or AIP-related deaths occurred. CONCLUSIONS: In this large international cohort of patients with concomitant AIP-IBD, most patients have type 2 AIP and colonic IBD. AIP course is relatively benign and long-term outcomes are favourable, but one-quarter develop pancreatic complications. Age, familial history of IBD, and CD may predict uncomplicated AIP course.

Herpes Simplex Virus Sepsis in a Young Woman with Crohn's Disease.

We present the case of a herpes simplex virus-1 [HSV-1] sepsis with severe herpes hepatitis in a young female treated with triple immunosuppressive therapy [adalimumab, azathioprine, prednisolone] for refractory Crohn's disease [CD]. The patient presented with high fever, generalised abdominal tenderness, strongly elevated transaminases, coagulopathy, and pancytopenia. Comprehensive diagnostics including blood HSV-1 polymerase chain reaction [PCR], liver biopsy, and immunohistochemistry revealed the diagnosis of fulminant herpes hepatitis. HSV-1 positivity of cutaneous lesions proved the disseminated nature of the infection. Early treatment with intravenous acyclovir led to a rapid improvement of the patient's condition and resulted in a full recovery of her liver function. This is the first reported case of HSV-sepsis in a patient with CD. Physicians treating inflammatory bowel disease [IBD] patients with combined immunosuppressive therapy should be aware of the possibility of herpes hepatitis, and early empirical antiviral therapy should be considered in immunosuppressed patients presenting with fever and severe anicteric hepatitis.