Retroperitoneal fibrosis: a retrospective clinical data analysis of 30 patients in a 10-year period

A review of the current treatment methods for retroperitoneal fibrosis with obstructive uropathy

Introduction and aims

Retroperitoneal fibrosis (RPF) is a fibroinflammatory disease in which patients may suffer obstructive uropathy (OU). The optimum treatment strategy for RPF with secondary OU is currently unclear, and the aim of this literature review is to assess the methods used to treat this patient cohort.

Methods

Medline, Embase, Cinahl, the Cochrane Library and PubMed were systematically searched to find studies assessing treatment outcomes in this patient cohort. After reviewing the studies' titles, abstracts and full texts, 12 were found that matched our search aims. Data from these publications were analysed and reported.

Results

The demographic and symptomatic features of patients across the 12 studies were representative of the general RPF population. No randomised control trials (RCTs) were found, and just one study formally compared outcomes between patients who underwent different treatment strategies. Many of the studies concluded that using medical and surgical methods in combination led to positive outcomes; whereas, others found positive outcomes following a variety of regimens. Many studies also highlighted, however, that significant minorities required further treatment after initial therapy. Conclusions regarding optimum treatment methods were limited as most publications did not formally compare outcomes following different strategies and had an observational study design.

Conclusion

Although positive outcomes were commonly seen following medical, surgical and a combination of treatments, the literature currently lacks research formally comparing outcomes after assigning specific treatment protocols to groups of RPF patients. More research is therefore required to determine how to best manage RPF leading to secondary OU.

Extravertebral low back pain: a scoping review

BACKGROUND

Low back pain (LBP) is one of the most common reasons for consultation in general practice. Currently, LBP is categorised into specific and non-specific causes. However, extravertebral causes, such as abdominal aortic aneurysm or pancreatitis, are not being considered.

METHODS

A systematic literature search was performed across MEDLINE, Embase, and the Cochrane library, complemented by a handsearch. Studies conducted between 1 January 2001 and 31 December 2020, where LBP was the main symptom, were included.

RESULTS

The literature search identified 6040 studies, from which duplicates were removed, leaving 4105 studies for title and abstract screening. Subsequently, 265 publications were selected for inclusion, with an additional 197 publications identified through the handsearch. The majority of the studies were case reports and case series, predominantly originating from specialised care settings. A clear distinction between vertebral or rare causes of LBP was not always possible. A range of diseases were identified as potential extravertebral causes of LBP, encompassing gynaecological, urological, vascular, systemic, and gastrointestinal diseases. Notably, guidelines exhibited inconsistencies in addressing extravertebral causes.

DISCUSSION

Prior to this review, there has been no systematic investigation into extravertebral causes of LBP. Although these causes are rare, the absence of robust and reliable epidemiological data hinders a comprehensive understanding, as well as the lack of standardised protocols, which contributes to a lack of accurate description of indicative symptoms. While there are certain disease-specific characteristics, such as non-mechanical or cyclical LBP, and atypical accompanying symptoms like fever, abdominal pain, or leg swelling, that may suggest extravertebral causes, it is important to recognise that these features are not universally present in every patient.

CONCLUSION

The differential diagnosis of extravertebral LBP is extensive with relatively low prevalence rates dependent on the clinical setting. Clinicians should maintain a high index of suspicion for extravertebral aetiologies, especially in patients presenting with atypical accompanying symptoms.

Serum IgG4 Concentration Is a Potential Predictive Biomarker in Glucocorticoid Treatment for Idiopathic Retroperitoneal Fibrosis

Objectives: To evaluate the management and outcome of idiopathic retroperitoneal fibrosis (iRPF) in Japan, and to identify its clinical biomarker. Methods: We retrospectively analyzed 129 patients with iRPF treated between January 2008 and May 2018 at 12 university and related hospitals. Patients treated with glucocorticoid were analyzed to identify a predictive biomarker. These patients were classified into three groups according to overall effectiveness (no change: NC, complete response: CR, and partial response groups: PR), and each parameter was compared statistically. Results: Male–female ratio was 5:1, and median age at diagnosis was 69 (33–86) years. Smoking history was reported in 59.6% of the patients. As treatment, 95 patients received glucocorticoid therapy with an overall response rate of 84%. As a result, serum concentration of IgG4 was significantly decreased in NC group compared with the other two groups (56.6 mg/dL vs. 255 mg/dL, 206 mg/dL, p = 0.0059 and 0.0078). ROC analysis was performed between the nonresponder (NC) and responder groups (CR + PR) to identify the cut-off value of serum IgG4 as a predictive marker. As a result, AUC of 0.793 was confirmed. Conclusions: Pre-treatment serum IgG4 concentration may have potential as a predictive biomarker of steroid treatment.

Comparison of laparoscopic and open ureterolysis for retroperitoneal fibrosis: Results from a tertiary referral center

OBJECTIVES

To compare the surgical outcomes of open and laparoscopic ureterolysis procedures in patients requiring surgical treatment for ureteral obstruction caused by retroperitoneal fibrosis.

MATERIALS

This study was designed retrospectively. The clinical records of patients who underwent ureterolysis between January 2005 and April 2019 due to ureteral obstruction caused by retroperitoneal fibrosis were examined. According to the type of surgery, the patients were divided into two groups as Group 1 (open ureterolysis) and Group 2 (laparoscopic ureterolysis). Demographic features, preoperative-postoperative renal functions, duration of follow-up with ureteral stents, and perioperative-postoperative complications were examined. The requirement of ureteral stent placement during the follow-up period was accepted as unsuccessful ureterolysis.

RESULTS

Ureterolysis was performed in 13 patients and 23 renal units. Eleven of these patients were male and two were female. The median age of the patients was 54 (44-68) years. There were six patients and 12 renal units in Group 1 and seven patients and 11 renal units in Group 2. Postoperatively, a total of four patients (30%) had minor complications (Clavien-Dindo 1-2) and one patient had a major complication (Clavien-Dindo 3a). Ureterolysis was determined to be successful in 21 of the renal units (91%) [11/12 (92%) in Group 1 vs 10/11 (91%) in Group 2]. No statistically significant difference was found between the groups in terms of the success and complication rates (p=1 and p=0.529, respectively). Postoperative hospitalization length and recovery time to return to normal preoperative activities were significantly shorter in Group 2 than Group 1 (p=0.011 and p=0.041, respectively).

CONCLUSIONS

The success and complication rates were similar between the open and laparoscopic methods for ureterolysis. Laparoscopic approach was advantageous over open approach in terms of postoperative hospitalization length and recovery time to return to normal preoperative activities.

Retroperitoneal fibrosis as a postoperative complication following renal transplantation in cats

OBJECTIVES

The aim of this report was to describe the clinical signs, diagnostic imaging findings, surgical management, histopathological findings, outcome and possible risk factors for cats that developed retroperitoneal fibrosis (RPF) following renal transplantation.

METHODS

Medical records of cats that underwent renal transplantation and developed clinically significant RPF between 1995 and 2019 were reviewed.

RESULTS

Eighty-one cats underwent 83 renal transplantations. Of these 81 cats, six developed clinically significant RPF. For all six cats, renal transplantation was performed using cold organ preservation solution and ureteral papilla implantation. Immunosuppression protocol included ciclosporin and prednisolone. All cats had at least one subtherapeutic trough ciclosporin level (<250 ng/ml) in the postoperative period. Cats presented with moderate-to-severe azotemia 39-210 days following renal transplantation. Abdominal ultrasonography and contrast pyelography revealed various degrees of hydroureter and hydronephrosis of the transplanted kidney. Surgical examination revealed a layer of dense fibrous tissue surrounding the transplanted kidney, ureter and bladder resulting in ureteral obstruction. Ureteral obstruction was managed by reimplantation of the proximal ureter or renal pelvis to the bladder. Histopathologic examination of the fibrous tissue and affected portion of the distal ureter revealed fibrous connective tissue with lymphoplasmacytic infiltration and perivascular inflammation suggestive of an autoimmune type reaction. Of the six cats, two died within 5 days after revision surgery, two developed signs consistent with recurrent partial ureteral obstruction (40 and 41 days after revision), one was euthanized 6 years later for an unrelated disease and one was lost to follow-up.

CONCLUSIONS AND RELEVANCE

The incidence of RPF in this population of cats was relatively low (7%), but still represents a significant cause of morbidity and mortality. The cause of RPF remains unknown, although investigation into suboptimal immunosuppression as a potential cause for local rejection reaction is warranted.

Idiopathic Retroperitoneal Fibrosis: An East African Diagnostic Challenge

Retroperitoneal fibrosis (RPF) is a rare disease with variable etiology characterized by chronic inflammation and fibrosis of tissue surrounding the abdominal aorta and iliac arteries. The majority of cases of RPF remain idiopathic and mostly reported in men. Glucocorticoids remain key in the treatment of RPF. Little has been reported on RPF in sub-Saharan Africa.

Outcomes of ureterolysis for primary retroperitoneal fibrosis: A single-center experience

OBJECTIVE

To report our experience with ureterolysis for the management of retroperitoneal fibrosis.

METHODS

The data of 25 patients who underwent ureterolysis due to primary retroperitoneal fibrosis between 2002 and 2017 were reviewed retrospectively. Initial symptoms, laterality, renal function status (initial/final), operation complications and serum creatinine levels (diagnosis/preoperative/6 months, 12 months postoperatively) were recorded. After surgery, patients were followed up by ultrasonography and serum creatinine levels. Patients with impaired results underwent furosemide renogram and/or late phase of computed tomography. Factors affecting final serum creatinine levels were evaluated. The χ² -test was used for nominal data among groups. The level of statistical significance was set as P < 0.05.

RESULTS

A total of 19 patients (76%) were operated bilaterally. The mean follow-up period was 46.2 ± 9.2 months. Among 44 operated renal units, non-functioning kidney developed in seven (15.9%). A total of 34 renal units (77.3%) did not require any additional surgical intervention, and two underwent balloon dilatation (4.5%), one (2.25%) followed with double J stent changes. Two patients developed end-stage renal disease secondary to bilateral unresolved obstruction. High final serum creatinine levels developed in eight (32%) patients without dialysis. Eight patients (32%) were treated with immunosuppressive therapy for systemic recurrence. There was a significant relationship between preoperative serum creatinine levels with final serum creatinine levels (P = 0.005). There was no statistically significant relationship between diagnosis serum creatinine levels with final serum creatinine levels and postoperative dialysis requirement (P = 0.79 and P = 0.817, respectively).

CONCLUSIONS

Ureterolysis provides acceptable success with low complication rates in patients with retroperitoneal fibrosis. Preoperative high-serum creatinine levels can be considered as a risk factor for long-term renal impairment and these patients should be followed closely.

Aortoenteric fistula secondary to an Inflammatory Abdominal Aortic Aneurysm

Primary aortoenteric fistulas are rare, with the annual incidence of such fistulas estimated to be 0.007 per million. The most common predisposing conditions for primary aortoenteric fistulas are atherosclerotic abdominal aortic aneurysms or penetrating atherosclerotic ulcers. We illustrate a rare case of an inflammatory aortic aneurysm causing a primary aortic fistula, with a direct fistulous jet from the aorta to the bowel with resultant catastrophic bleeding. In contrast to atherosclerotic aneurysms, most inflammatory aneurysms are symptomatic and show dense perianeurysmal fibrosis and periaortic wall thickening. A direct jet of contrast extravasation from the aorta into a bowel loop, while rarely seen, remains the most specific sign of a primary aorta-enteric fistula. A comprehensive literature review of the clinical presentation, imaging features, and differential diagnosis of a primary aortoenteric fistula are also discussed.

[18F]-Fluorodeoxyglucose Positron Emission Tomography in the Diagnosis, Treatment Stratification, and Monitoring of Patients with Retroperitoneal Fibrosis: A Prospective Clinical Study

BACKGROUND

The ability to distinguish malignant from benign retroperitoneal fibrosis (RPF) and to select patients who are likely to respond to steroid treatment using a noninvasive test would be a major step forward in the management of patients with RPF.

OBJECTIVE

To prospectively evaluate the potential of [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) to improve clinical decision-making and management of RPF.

DESIGN, SETTING, AND PARTICIPANTS

A total of 122 RPF patients were assessed and managed by a multidisciplinary RPF service between January 2012 and December 2015. Of these, 78 patients underwent 101 FDG-PET scans, as well as computed tomography and blood tests. Management was based on the findings from these investigations. Median follow-up was 16 mo.

RESULTS AND LIMITATIONS

Of the 24 patients with negative [18F]-FDG-PET, none (0%) had malignancy on biopsy (negative predictive value 100%). [18F]-FDG-PET identified malignancy in 4/4 patients (100%) before biopsy. All four patients had highly avid PET (maximum standardised uptake value ≥4) with atypical avidity distribution. [18F]-FDG-PET revealed avidity in 19/38 patients (50%) with normal inflammatory markers and no avidity in 10/63 patients (16%) with raised marker levels. Patients with highly avid PET were significantly more likely to respond to steroids compared to those with low avidity (9/11 [82%] vs 3/24 [12%]; p<0.01) or negative PET (9/11 [82%] vs 0/14 [0%]; p<0.01). Limitations include the small number of patients and the predominance of tertiary referrals, which may represent patients with particularly problematic RPF.

CONCLUSIONS

This study has established a promising role for [18F]-FDG-PET in optimising and individualising the treatment of RPF.

PATIENT SUMMARY

This study shows that [18F]-fluorodeoxyglucose positron emission tomography scans could reduce the need for biopsy in patients with retroperitoneal fibrosis (RPF). This technique can distinguish cancer from noncancerous RPF, and may be better than blood tests in assessing and monitoring RPF. It also appears to predict a patient's response to steroids, which should allow more individualised treatment.

Differentiation of Lymphoma Presenting as Retroperitoneal Mass and Retroperitoneal Fibrosis: Evaluation with Multidetector-row Computed Tomography

Background:

Retroperitoneal fibrosis (RPF) and lymphoma presenting as retroperitoneal mass may closely resemble each other and misdiagnosis may occur. This study investigated the differential imaging features of RPF and lymphoma which presented as a retroperitoneal soft tissue using multidetector-row computed tomography (MDCT).

Methods:

The 42 consecutive patients were included in this retrospective review, including 19 RPF patients (45.2%; including 13 males and 6 females; mean age: 56.7 ± 6.2 years) and 23 patients with lymphoma (54.8%; including 14 males and 9 females; mean age: 57.4 ± 12.3 years). An array of qualitative computed tomography (CT) features of lesions in 42 consecutive patients with newly diagnosed untreated RPF and lymphoma were retrospectively analyzed. The quantitative size of the lesion at the para-aortic region and attenuation in the precontrast, arterial, and portal phases were calculated in regions of interest and compared between the patients with newly diagnosed untreated RPF and with lymphoma. Receiver operating characteristic curve analysis was used to assess the potential diagnostic value of each quantitative parameter. Inter-reader concordance was also calculated.

Results:

Mean ages between patients with RPF and lymphoma were not significantly different (56.7 ± 6.2 years vs. 57.4 ± 12.3 years P = 0.595). Compared to those in patients with lymphoma, homogeneous enhancement (65.2% vs. 94.7%, P = 0.027) and pelvic extension (52.2% vs. 89.5%, P = 0.017) were significantly more common while the involvement of additional nodes (78.3% vs. 5.3%, P < 0.001), suprarenal extension (60.9% vs. 15.8%, P = 0.004), and aortic displacement (43.5% vs. 5.3%, P = 0.006) were significantly less common in patients with RPF. Lesion size at the para-aorta was significantly greater in patients with lymphoma, compared with RPF patients (3.9 ± 1.2 cm vs. 1.8 ± 0.6 cm; P < 0.001). The attenuation values in three phases were not significantly different between patients with RPF and lymphoma. Inter-reader concordance for subjective features ranged from very good to excellent (range: 85.7–100.0%).

Conclusions:

This study showed that MDCT can help differentiate between untreated RPF and lymphoma on the basis of qualitative CT features and lesion sizes. Differentiating RPF from lymphoma on the basis of attenuation values in the precontrast, arterial, and portal phases was difficult to accomplish.

Idiopathic retroperitoneal fibrosis causing unilateral ureteral and sigmoid colon obstruction: A case report

OBJECTIVE

The present report aimed to present a unique case of idiopathic retroperitoneal fibrosis (RPF) presenting features of unilateral ureteral and sigmoid colon obstruction. RPF is a rare disorder with unclear etiology.

CASE REPORT

A 43-year-old female had a 10-day history of lower right abdominal and lumbar pain. Gynecological examination, ultrasound, and computed tomography (CT) were all suggestive of right ovarian tumor. An enhanced CT showed right-sided hydronephrosis. The patient was diagnosed as having ovarian cancer. Ten days after hospitalization, a right intraureteral stent with a double-J catheter was inserted. Upon exploring the abdomen, unyielding RPF was encountered. A partial sigmoidectomy and colostomy were performed. Postoperative pathological results suggested idiopathic RPF. She received steroid treatments.

CONCLUSION

RPF is a rare disease that can be misdiagnosed. Our understanding about its presentation has to be improved and it should be considered as a differential diagnosis for patients presenting with abdominal diseases.

Diagnosis and follow-up of idiopathic retroperitoneal fibrosis: role of (18)F-FDG-PET/CT and biochemical parameters in patients with renal involvement

Idiopathic retroperitoneal fibrosis (IRF) is a rare disease characterized by fibro-inflammatory reaction surrounding ureters and other inner organs with possible secondary renal involvement. Symptoms are aspecific and recurrent phases of activity are generally associated with elevation of inflammatory indices. 18F-FDG-PET is nowadays an important tool for the detection of this disease, allowing differentiation between metabolically active tissue and fibrotic one. The purpose of this study was to investigate the role of 18F-FDG-PET in the management of IRF and to evaluate possible correlations between biochemical parameters and PET/CT findings of disease activity. We enrolled seven consecutive patients with IRF (in five histology proved the disease) observed from 2003 to 2012 (5 M:2 F, mean age 53.8 years, range 44-86 years). All patients presented with fever as first symptom; two had obstructive renal failure requiring hemodialysis; one underwent monolateral nephrectomy for parenchyma infiltration; six presented ureteral involvement; three underwent ureteral stent placement. For each patient, during a mean total follow-up of 26.5 months we evaluated serum creatinine, BUN, Hb, RBCs, WBCs, PLT, CRP, ESR. Periodic 18F-FDG-PET/CT scans (every 5.9 months-mean) were performed in all patients. Statistical evaluation was performed using "stepwise regression" analysis. Steroids and immunosuppressive agents induced a progressive normalization of PET/CT scans in all patients at the end of follow-up. Stepwise regression analysis showed that BUN, serum creatinine and CRP only if considered together, significantly correlated with SUV max (p value = 0.000003057). 18F-FDG-PET is a useful tool for clinical decision making in patient with IRF, allowing to evaluate the efficacy of the pharmacological treatment and to detect early recurrences, to modify the therapeutic approach. Acute phase reactants are not reliable alone for the management and the follow-up as they are often not concordant with metabolic assessment of the disease. In patients with ureteral involvement, CRP together with BUN and serum creatinine has a significant correlation with PET/CT results, and can help physicians in therapeutic approach, better than a single parameter.