An aortoduodenal fistula as a complication of immunoglobulin G4-related disease

A case of aortoduodenal fistula caused by IgG4-related periaortitis

An 86-year-old man who underwent endovascular aortic repair for impending rupture of an abdominal aortic aneurysm a year ago presented to our hospital because of fatigue and black stools. Multiple bacterial specimens were detected in blood cultures, and computed tomography following oral administration of gastrografin demonstrated gastrografin in the abdominal aorta. The diagnosis of aortic duodenal fistula was confirmed and emergency abdominal aortic replacement was performed. The pathological findings of the aorta included a large number of immunoglobulin G4 (IgG4)-positive plasma cells infiltrating all layers of the aortic wall, with particularly marked thickening of the adventitia. The serum IgG4 level was 241 mg/dl and IgG4-related periaortitis was diagnosed. Aortoduodenal fistula is a rare but fatal complication of IgG4-related periaortitis. Patients should be followed carefully after endovascular aortic repair for inflammatory abdominal aortic aneurysms.

It Is Not Always Diverticular Bleeding: Fatal Subtle Primary Aorto-Duodenal Fistula Associated With Abdominal Aortic Aneurysm

Primary aorto-duodenal fistula (PADF) is a connection between the aorta and duodenum without prior aortic surgery. We present a case of an 80-year-old female who presented with hematochezia. She was vitally stable but later developed a large episode of hematemesis followed by cardiac arrest. A computed tomography angiogram (CTA) chest scan showed an abdominal aortic aneurysm (AAA) with no leakage or rupture. Esophagogastroduodenoscopy (EGD) demonstrated blood in the stomach and duodenum, but no source was identified. Tagged RBC scan showed massive hemorrhage in the stomach and proximal small bowel. Further review of the CT images identified a subtle PADF. The patient underwent endovascular aneurysm repair but died shortly after. Physicians should maintain a high awareness of PADF, particularly in elderly patients with obscure gastrointestinal bleeding with or without known AAA. Herald bleeding in the setting of an aortic aneurysm should raise suspicion for PADF even in the absence of extravasation on CTA.

Adventitial matrix metalloproteinase production and distribution of immunoglobulin G4-related abdominal aortic aneurysms

Objective

IgG4-related diseases are systemic inflammatory fibrous lesions characterized by elevated serum IgG4 and infiltration of IgG4-positive plasmacytes. They can manifest in vascular lesions as frequently formed aneurysms with prominent thickening of the adventitia (IgG4-related abdominal aortic aneurysm; IgG4-AAA). Matrix metalloproteinases (MMPs) degrade the extracellular matrix, mainly in the tunica media, resulting in destruction of aortic structures to cause enlargement of the aneurysm. However, the expression of adventitial MMPs in IgG4-AAAs is poorly understood.

Methods

MMPs and MMPs-presenting cells in the adventitia of IgG4-AAAs (n = 19) of human surgical specimens were evaluated by immunohistochemistry and dual messenger RNA in situ hybridization. The results were compared with those from control groups of non-IgG4-related inflammatory AAA (n = 18), atherosclerotic AAA (aAAA; n = 11), and autopsy cases (n = 11). Preoperative serum MMPs levels of these groups were compared with the histologic data.

Results

Expression of MMP-9, MMP-2, and MMP-14 at the protein and messenger RNA levels in the adventitia was significantly higher in IgG4-AAAs than in controls. Other MMPs were scarce. The total number of MMP-9-positive cells was positively correlated with the diameter of the aneurysm (R = 0.461; P = .031), the adventitial thickness (R = 0.688; P < .001), and the number of IgG4-positive cells (R = 0.764; P < .001). Within lymphoid follicles, MMP-9-presenting cells were predominantly detected in large follicular dendritic cells, followed by histiocytes, fibroblasts, and plasmacytic dendritic cells. Outside lymphoid follicles, fibroblasts, and histiocytes mainly expressed MMP-9, and tissue dendritic cells also produced MMP-9. The levels of MMP-9 derived from follicular dendritic cells and histiocytes and plasmacytic dendritic cells outside lymphoid follicles were significantly higher in IgG4-AAA group than in other groups. Expression of adventitial MMP-2 and MMP-14 by histiocytes and fibroblasts was predominantly detected outside lymphoid follicles. Serum MMP-9 levels were significantly higher in IgG4-AAAs (835 ng/mL) than in controls, and correlated with serum IgG4 levels and the total numbers of adventitial MMP-9-positive cells, whereas serum MMP-2 levels did not differ among the three aneurysmal groups.

Conclusions

MMP-9 production in adventitial immune cells concerning lymphoid follicles was characteristic of IgG4-AAAs and might work in its activity with aneurysmal dilatation and adventitial thickening. Expressions of adventitial MMP-2 and MMP-14 were detected in histiocytes and fibroblasts outside lymphoid follicles, and were less concerned with the activity of IgG4-AAAs.

This retrospective multicenter study analyzed adventitial matrix metalloproteinases (MMPs) production in 19 patients with IgG4-related abdominal aortic aneurysms (AAAs) and 40 control cases. Adventitial MMP-9 production by various kinds of immune cells was increased in patients with IgG4-related AAAs and concerned with IgG4-AAA activity to cause aneurysmal progression and adventitial fibrosis, compared with aAAA. Serum MMP-9 levels reflected histologic MMP-9. Adventitial MMP-2 and MMP-14 were less concerned with IgG4-AAA activity. Thus, for IgG4-AAA patients, monitoring serum MMP-9 level might be the exacerbating factors related to adverse events during the treatment course.

Multimodalities Imaging of Immunoglobulin 4-related Cardiovascular Disorders

Immunoglobulin 4 (IgG4)-related systemic disease (IgG4-RSD) is a systemic inflammatory disease characterized by elevation of serum IgG4. IgG4-RSD can affect any organ in the body, and the list of organs associated with this condition is growing steadily. IgG4-related cardiovascular disease affects the coronary arteries, heart valves, myocardium, pericardium, aorta, pulmonary and peripheral vessels. Echocardiography is the most commonly used non-invasive imaging method. Computed tomography angiography (CTA) can assess aortitis, periarteritis and coronary aneurysms. Coronary CTA is fast, offers high spatial resolution and a wide coverage field of view. Cardiac magnetic resonance imaging (CMR) offers a comprehensive evaluation of the cardiovascular system including cardiac function, extent of myocardial fibrosis, characterise cardiac masses with different pulse sequences and guide to further treatment. Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) can provide important information about the extent of disease, the presence of active inflammation and the optimum biopsy site. In general, the role of diagnostic imaging includes establishing the diagnosis, detecting complications, guiding biopsy and documenting response to therapy.

Primary aortoduodenal fistula associated with abdominal aortic aneurysm with presentation of gastrointestinal bleeding: a case report

Background

Primary aortoduodenal fistula (ADF) is a rare cause of gastrointestinal (GI) bleeding and is difficult to diagnose as the clinical presentation is subtle. Clinicians should keep a high level of suspicion for an unknown etiology of GI bleeding, especially in older patients with or without abdominal aortic aneurysm (AAA). Computed tomographic angiography (CTA) can be used to detect primary ADF. Open surgery or endovascular aortic repair (EVAR) for ADF with bleeding will improve the survival rate.

Case presentation

We report a rare case of AAA complicating ADF with massive GI bleeding in a 73-year-old Taiwanese man. He presented with abdominal pain and tarry stool for 5 days and an initial upper GI endoscopy at a rural hospital showed gastric ulcer only, but hypotension with tachycardia and a drop in hemoglobin of 9 g/dl from 12 g/dl occurred the next day. He was referred to our hospital for EVAR and primary closure of fistula defect due to massive GI bleeding with shock from ADF caused by AAA. Diagnosis was made by CTA of aorta.

Conclusions

A timely and accurate diagnosis of primary ADF may be challenging due to insidious episodes of GI bleeding, which are frequently under-diagnosed until the occurrence of massive hemorrhage. Clinical physicians should keep a high index of awareness for primary ADF, especially in elderly patients with unknown etiology of upper GI bleeding with or without a known AAA.

A case of immunoglobulin G4-related aortic diseases

A 65‐year‐old man had histories of retroperitoneal fibrosis, membranous nephropathy, and acute coronary syndrome. Chest computed tomography showed an enlarged ascending aorta and type B aortic dissection, and he underwent ascending aorta and arch replacement. A pathological examination of the resected aorta showed immunoglobulin G4‐positive plasma cell infiltration.

Colovesical fistula caused by glucocorticoid therapy for IgG4-related intrapelvic mass

IgG4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory disorder that can occur in almost all systemic organs and generally responds to corticosteroid treatment. We report a rare case of an IgG4-related intrapelvic mass lesion that responded to steroid therapy but caused a fistula between the sigmoid colon and bladder. A 71-year-old man was followed after treatment for hepatocellular carcinoma. Follow-up computed tomography (CT) incidentally depicted left hydronephrosis with an ill-demarcated intrapelvic mass lesion. This lesion was histologically diagnosed as IgG4-RD by open biopsy, and peroral steroid therapy was initiated. One month after starting steroids, a colovesical fistula was detected by follow-up CT. A colostomy and urethral catheterization were emergently performed. The patient recovered and the mass lesion was drastically minimized by the initiation of glucocorticoids; however, he still needs urethral catheterization. IgG4-RD develops in various systemic organs and generally responds well to steroids. Clinicians must be watchful for the complications of responses to corticosteroids, such as fistulization, when the mass lesion of IgG4-RD is adjacent to multiple luminal organs.