Retroperitoneal fibrosis: single-centre experience from 1992 to 2010, current status of knowledge and review of the international literature

Renal Involvement in Retroperitoneal Fibrosis: Prevalence, Impact and Management Challenges

Retroperitoneal fibrosis (RPF) is a rare disorder consisting of idiopathic and various secondary forms and characterized by chronic inflammatory infiltrates and marked fibrosis in the retroperitoneal space. In idiopathic RPF (IRPF), 35–60% of cases have been reported to be IgG4-related RPF, the retroperitoneal lesions of IgG4-related disease (IgG4-RD). IRPF can frequently lead to renal insufficiency mediated by urinary tract obstruction and hydronephrosis irrespective of being IgG4-related or not. Clinical pictures, laboratory and imaging findings, and location of the urinary tract obstruction are generally similar in IgG4-related and non-IgG4-related IRPF although multiple organ involvement and serum IgG4 elevation may be characteristic of the IgG4-related forms. Periaortic/periarterial lesions are the most frequent cause of renal insufficiency. Although the response to glucocorticoids is generally good, relapse does occur in a considerable proportion of patients, and may require an additional immunosuppressive agent and/or urological intervention in cases with multiple relapses or refractory obstructive uropathy. In general, the prognosis of patients with IRPF is good, but careful attention needs to be paid to chronic kidney disease as a major complication and rupture of the affected aorta/artery as a life-threatening one. Further studies are necessary to better understand the pathogenesis of the disease and to establish the optimal diagnostic and therapeutic strategies for it.

Clinical characteristics of IgG4-related retroperitoneal fibrosis versus idiopathic retroperitoneal fibrosis

Retroperitoneal fibrosis (RPF) is an uncommon condition characterized by inflammation and fibrosis in the retroperitoneal space. More than two-thirds of RPF are idiopathic, with the remaining stemed from a variety of secondary causes. It was suggested that IgG4-related RPF is a secondary form of RPF. We undertook this study to compare detailed demographic, clinical and laboratory characteristics of IgG4-related RPF and IRPF in a large Chinese cohort. We retrospectively reviewed the medical records of 132 RPF patients diagnosed at Peking University People’s Hospital between March 2010 and March 2018. Among the 132 patients, the mean age at disease onset was 54.8 years. IgG4-related RPF group showed greater male predominance compared to IRPF group. IgG4-related RPF patients showed a longer interval between symptom onset and diagnosis, and allergic diseases were more common in this group. Sixty-four patients (48.4%) had lower back pain, which was more common in IRPF group than that in IgG4-related RPF patients. In terms of organ involvement, although 42 of 47 patients (89.3%) with IgG4-related RPF had other organ involvement, there were no patients in the IRPF group with other organ involvement. In addition, the serum IgG4 level, elevated eosinophils counts and IgE level were significantly higher in IgG4-related RPF patients. We described the demographic, clinical and laboratory differences between IgG4-related RPF and IRPF patients, indicating their potential differences in pathogenesis, which was of great importance to diagnose and manage the two phenotypes.

Idiopathic retroperitoneal fibrosis: an update for nephrologists

Idiopathic retroperitoneal fibrosis (IRF) is a rare condition characterized by the development of a peri-aortic and peri-iliac tissue showing chronic inflammatory infiltrates and pronounced fibrosis. Ureteral entrapment with consequent obstructive uropathy is one of the most common complications of IRF, which can lead to acute renal failure and, in the long term, to varying degrees of chronic kidney disease. IRF may be isolated or develop in association with autoimmune diseases (e.g. Hashimoto's thyroiditis and psoriasis) and other fibro-inflammatory disorders (often within the spectrum of immunoglobulin G4-related disease), which suggests that it should be considered as a potentially systemic condition. IRF is an immune-mediated disease: genetic variants (e.g. human leukocyte antigen (HLA)-DRB1*03) and environmental agents (mainly exposure to asbestos and smoking) are strongly associated with an increased risk of developing the disease, while a complex network of chemokines (e.g. CXCL12 and C-C moti chemokine 11 (CCL11)) and cytokines [e.g. interleukin (IL)-6, IL-12 and IL-13] is likely to orchestrate the inflammatory response and simultaneously promote fibrosis. Glucocorticoids, alone or in combination with traditional immunosuppressants such as methotrexate and mycophenolate mofetil, are usually efficacious and promptly induce disease remission; however, up to 50% of patients relapse, thus requiring repeat immunosuppressive courses. Biologic drugs, namely rituximab, are being explored for the treatment of IRF. In addition to medical therapies, interventional procedures (mainly ureteral stenting) are required to relieve ureteral obstruction, whereas surgical ureterolysis is generally reserved to refractory cases. If appropriately treated, then the overall and renal prognosis of IRF are good, with <5% patients developing end-stage renal disease.

Idiopathic retroperitoneal fibrosis: clinicopathologic features and outcome analysis

To describe clinical features and outcomes of 26 patients with idiopathic retroperitoneal fibrosis from a single center, we reviewed medical records of consecutive patients with idiopathic retroperitoneal fibrosis evaluated at our facility from January 1, 1998 to December 31, 2013 for clinical features, laboratory and radiographic findings, management, and outcomes. Twenty-six patients met criteria for idiopathic retroperitoneal fibrosis and were included in the study. Median age at diagnosis was 58 years; male-female ratio was 3.3:1.0. Median duration of symptoms was 7 weeks. Abdominal, flank, and/or low back pain were the most common presenting symptoms. Four patients (15 %) had associated autoimmune or fibrosing disorders. Baseline erythrocyte sedimentation rate was elevated in 17 (77 %) of 22 patients tested and C-reactive protein was elevated in 10 (56 %) of 18 patients tested. Hydronephrosis was present in 17 (68 %) patients; 8 (47 %) of 17 had bilateral hydronephrosis. Retroperitoneal mass biopsy was performed in 18 (69 %) patients. Two patients had idiopathic retroperitoneal fibrosis classifiable as IgG4-related disease. Therapy consisted of medications alone in 7 cases, surgical interventions alone in 7 cases, and a combination in 11 cases. One patient achieved remission with no treatment. Most patients treated medically received initial corticosteroids. Methotrexate (1 case), azathioprine (1 case), mycophenolate mofetil (1 case), and tamoxifen (5 cases) were used. No relapses occurred after a median 5-year follow-up. Two (8 %) patients died; five (19 %) developed cancer after diagnosis. In this series, we emphasize the importance of early diagnosis and therapy for overall favorable prognosis of idiopathic retroperitoneal fibrosis.

Retroperitoneal fibrosis

Retroperitoneal fibrosis (RPF) is a condition characterized by the presence of inflammation and fibrosis in the retroperitoneal space, for which no standard diagnostic criteria exist. Historically, treatment has focused on relieving the obstruction with percutaneous or cystoscopic assisted placement of ureteral stents followed by more definitive resolution of ureteric obstruction with open or laparoscopic ureterolysis. However, over the past several years management has shifted from primarily a surgical approach to an immunosuppressive-based therapy aimed at modulation of the immune system. This review focuses on the recent advances in the classification, epidemiology, pathophysiology, pathology, imaging, and treatment of RPF.