Idiopathic Retroperitoneal Fibrosis

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.

Atypical Presentation of Retroperitoneal Fibrosis Causing Colonic Obstruction: A Case Report

Retroperitoneal fibrosis (RPF), also referred to as Ormond's disease, is a rare fibroinflammatory condition characterized by abnormal fibrous tissue deposition in the retroperitoneal space, which traditionally presents with ureteral obstruction. Nonetheless, our case report showcases an exceptional instance involving a 70-year-old female patient who presented with symptoms suggestive of colonic obstruction, an unusual presentation that is not commonly associated with RPF. Although RPF has established associations with autoimmune conditions such as immunoglobulin G4-related disease and systemic lupus erythematosus, its connection to colonic obstruction remains undocumented in the medical literature. Our patient is a 70-year-old female who presented with constipation, anemia, and fecal occult blood. Her past medical history included a hysterectomy due to fibroids, right breast lumpectomy, type 2 diabetes mellitus, subclinical hyperthyroidism, hypertension, and obesity. Upon physical examination, the patient's abdomen appeared protuberant but was non-tender to palpation. Bowel sounds were normal, and there was no distension. Notably, there was no tenderness in the right or left costovertebral angles, nor was there any guarding. Workup with colonoscopy could not be completed due to the inability to pass a colonoscope beyond the rectosigmoid junction. Further workup with barium enema confirmed an apple core lesion seen in the rectosigmoid concerning for a neoplastic or inflammatory process. Finally, a computed tomography scan of the abdomen and pelvis showed a 7.1 cm right pelvic mass attached to the bladder and cecum, moderate right hydroureteronephrosis, and a 5.2 cm left adnexal mass with soft tissue changes narrowing the sigmoid colon. The next step was to take the patient for an exploratory laparotomy. During exploratory laparotomy, extensive adhesions and desmoplastic reactions were observed in the pelvic region, involving the sigmoid colon, bladder, cecum, and appendix. Two firm masses were identified in the retroperitoneum, one located in the left lower quadrant (LLQ) adherent to the posterior wall of the sigmoid colon and one in the right lower quadrant (RLQ) adherent to the posterior wall of the cecum. Three specimens were sent to pathology for further examination: a portion of the sigmoid colon, a resection from the RLQ mass, and a resection from the LLQ mass. Pathology reported dense fibrotic masses with abscess-like formation, reactive in nature and of unclear etiology, and negative for malignancy. They were negative for fibromatosis (β-catenin negative), and IgG4+/IgG+ was approximately 5%. Interestingly, the LLQ mass also contained remnants of the fallopian tube and ovary and benign cystic changes. This case report presents a unique and atypical presentation of RPF, deviating from the conventional presentation of ureteral obstruction. The patient's initial symptoms suggested colonic obstruction, a clinical scenario rarely linked to RPF. This case underscores the significance of considering diverse clinical presentations when diagnosing RPF, thereby expanding our comprehension of the condition's clinical spectrum and ultimately refining patient care and management.

Role of transduodenal endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/FNB) for diagnosis of retroperitoneal fibrosis (Ormond's disease)

BACKGROUND

Retroperitoneal fibrosis (RPF), often referred to as Ormond's disease when it is of idiopathic origin, is a rare disease characterized by the presence of inflammatory infiltrates and periaortic masses in the retroperitoneum. For a definite diagnosis, a biopsy and subsequent pathological examination is required. Currently accepted methods for retroperitoneal biopsy include open, laparoscopic, or CT-guided approaches. However, transduodenal endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/FNB) for diagnosis of RPF has attracted only little attention in the literature.

CASE REPORTS

We report two male patient cases who presented with leukocytosis, elevated C-reactive protein, and a suspicious retroperitoneal mass of unknown origin on computed tomography. One patient also reported left lower quadrant pain, whereas the other patient suffered from back pain and weight loss. In both patients, idiopathic RPF was successfully diagnosed by using transduodenal EUS-FNA/FNB with 22- and 20-gauge aspiration needles. Histopathology revealed dense lymphocytic infiltrates and fibrosis. The procedures lasted approximately 25 and 20 minutes, respectively, and in both patients no serious adverse events occurred. Treatment included steroid therapy and administration of Azathioprine.

CONCLUSION

We demonstrate that using EUS-FNA/FNB to diagnose RPF is a feasible, fast, and safe method, which should always be considered as a first-line diagnostic modality. Hence, this case report emphasizes that gastrointestinal endoscopists are likely to play an important role in the setting of suspected RPF.

IgG4-related retroperitoneal fibrosis with acute kidney injury: a case report and literature review

IgG4-related retroperitoneal fibrosis is a rare cause of renal dysfunction that usually manifests as obstructive nephropathy (sometimes with extrarenal manifestations). Due to the non-specific symptoms at the onset of the disease and often latent course, special laboratory and instrumental examination methods are usually needed to establish a diagnosis. The article describes a clinical case of a relapse of IgG4-related retroperitoneal fibrosis in a 53-year-old patient, who developed bilateral ureterohydronephrosis with postrenal acute kidney injury after the withdrawal of glucocorticoid therapy. The patient underwent bilateral percutaneous nephrostomy and resumed glucocorticoids at a dose of 30 mg/day. Postobstructive diuresis was 22 L. Treatment resulted in a complete normalization of the creatinine level and transient hypokalemia, which was eliminated with potassium medications. At the final stage of the treatment, bilateral stenting of both ureters was performed with a tapering of glucocorticoids to 5 mg per day with CT control of the retroperitoneal space after 5 months. A clinical case demonstrates that an interruption of glucocorticoid treatment in patients with IgG4-related retroperitoneal fibrosis can lead to ureterohydronephrosis with the development of acute kidney injury. In such cases, stenting of the ureters could be considered an optimal therapeutic option.

A case of ureteral stenosis due to ureteritis probably associated with rheumatoid arthritis

Ureteritis associated with the immunological disorder is rarely reported, and most cases in this category are small vessel vasculitis and immunoglobulin G4-related disease. Rheumatoid arthritis (RA)-associated ureteritis is uncommon, and underlying aetiology is unclear. We present a patient with ureteritis who had a medical history of RA and was successfully treated with steroids and immunosuppressant. A 49-year-old woman who had been treated for RA and atopic dermatitis suffered from gross haematuria for 5 successive days. Contrast-enhanced computed tomography (CT) showed right-dominant upper urinary tract dilatation with enhanced thickened wall. The haematuria continued accompanied with intermittent right back and lower abdominal pain, and the following CT image taken after 3 months presented the progression to bilateral hydronephrosis. Ureteral stents were placed, and antibiotic therapy was introduced for obstructive pyelonephritis. Ureterocystoscopy and following biopsy from the upper ureteral tract showed a chronic inflammatory change in the histopathology, and we finally considered the stenosing ureteritis to be caused by immune-mediated mechanism related to RA. After starting steroid therapy with methotrexate, therapeutic response was obtained to remove the stents. In the cases of ureteritis or ureteral stenosis of unknown aetiology with a medical history of immunological disorders, we should consider the underlying immune-activated state and try to test contrast-enhanced CT and histological examination before performing a surgical procedure. After excluding the common causes of ureteritis or ureteral stenosis, these tests would support the appropriate diagnosis.

Combined therapy of prednisone and mTOR inhibitor sirolimus for treating retroperitoneal fibrosis

OBJECTIVES

Retroperitoneal fibrosis (RPF) is a rare autoimmune disease with fibrous tissue growth and inflammation in retroperitoneum. Its current treatments involve long-term uptake of glucocorticoids (e.g., prednisone) for controlling inflammation; however, side effects are common. We strived for an improved therapy for fibrosis remission while reducing side effects.

METHODS

We surveyed gene-disease-drug databases and discovered that mammalian target of rapamycin (mTOR) was a key signalling protein in RPF and the mTOR inhibitor compound sirolimus affected many RPF pathways. We designed a therapy combining a gradual reduction of prednisone with a long-term, stable dosage of sirolimus. We then implemented a single-arm clinical trial and assessed the effects in eight RPF patients at 0, 12 and 48 weeks of treatment by measuring fibrous tissue mass by CT, markers of inflammation and kidney functions by lab tests, immune cell profiles by flow cytometry and plasma inflammatory proteins by Olink proteomics.

RESULTS

With the combined therapy, fibrous tissue shrunk about by half, markers of acute inflammation reduced by 70% and most patients with abnormal kidney functions had them restored to normal range. Molecularly, fibrosis-related T cell subsets, including TH2, TH17 and circulating TFH cells, were reduced and tumour necrosis factor and related cytokines restored to healthy levels. No severe long-term side effects were observed.

CONCLUSIONS

Our combined therapy resulted in significant fibrosis remission and an overall regression of the immune system towards healthy states, while achieving good tolerance. We concluded that this new therapy had the potential to replace the steroid monotherapy for treating RPF.

Generalized crystal-storing histiocytosis with noncirrhotic portal hypertension: an autopsy case report

Crystal-storing histiocytosis (CSH) is a rare disease associated with the accumulation of histiocytes containing crystalline matter within their cytoplasm. Herein, we present the case of a female patient who was diagnosed with Tolosa-Hunt syndrome at 45 years of age and idiopathic retroperitoneal fibrosis when she was 48 years. She developed portal hypertension (PH), but did not present with cirrhosis; as such, the cause of PH was not identified. Her PH gradually worsened when she was 54 years, and at the age of 60 years, she died from an acute subdural hematoma. Autopsy revealed retroperitoneal fibrosis with severe fibrosis extending around the hepatic veins and into the porta hepatis. Histologically, the retroperitoneal tissue showed a dense infiltrate of eosinophilic histiocytes with crystal structures in the cytoplasm, which was pathologically diagnosed as CSH. Nodular regenerative hyperplasia was observed in the liver parenchyma, whereas cirrhosis was not. In the present case, CSH caused fibrosis, which was believed to be the cause of PH. In addition, we considered that nodular regenerative hyperplasia caused by the altered hepatic blood flow due to treatment of gastric varices contributed to worsening PH. Hence, CSH should be considered as an underlying disease in noncirrhotic portal hypertension.

New-onset retroperitoneal fibrosis following COVID-19 mRNA vaccination: Coincidental or vaccine-induced phenomenon?

The Pfizer-BioNTech mRNA vaccine is a US Food and Drug Administration-approved coronavirus disease 2019 (COVID-19) vaccine. Although it is reported to be safe and effective, immune dysregulation leading to autoimmunity has become an area of concern. Retroperitoneal fibrosis (RPF) is an immune-mediated fibroinflammatory disease characterized by the deposition of fibrous tissues, primarily around the abdominal aorta and iliac arteries. Herein, we report a case of RPF following Pfizer BioNTech COVID-19 mRNA vaccination. To the best of our knowledge, there have been no published reports on RPF after COVID-19 mRNA vaccination. A 58-year-old woman with no history of autoimmune diseases presented with acute onset of epigastric pain 5 weeks after the second dose of the Pfizer-BioNTech vaccine. She had been diagnosed with stage I breast cancer 9 years ago and was in complete remission on admission. Abdominal computed tomography showed preaortic soft-tissue infiltration around the origin of the superior mesenteric artery but no evidence of breast cancer recurrence. Considering the temporal relationship between current symptoms and vaccination and the absence of other possible causes, she was diagnosed with RPF secondary to Pfizer-BioNTech vaccine-induced autoimmunity. This case may raise awareness of the possibility of RPF development following COVID-19 mRNA vaccination.

Chronic periaortitis: A clinical approach

Chronic periaortitis (CP) is a rare disease characterised by the presence of a fibro-inflammatory tissue typically enveloping the abdominal aorta, the iliac arteries and, in some cases, the nearby structures, such as the ureters and the inferior vena cava. Imaging plays a key role in the diagnosis and follow-up: computed tomography and magnetic resonance imaging scans are used to define the extension of the pathological tissue, whereas fluorodeoxyglucose positron emission tomography is the gold standard to establish the degree of its metabolic activity. CP must be distinguished from secondary forms of periaortic infiltration, which include malignant, infectious, and drug-related aetiologies. This review focuses on the clinical aspects of CP and the differential diagnosis with secondary cases, and aims to provide the clinician with a guide through this challenging clinical approach.

Effective therapy of pirfenidone in a patient with idiopathic retroperitoneal fibrosis: report of a case

Idiopathic retroperitoneal fibrosis (iRPF) is a chronic autoimmune disease characterized by fibroinflammatory tissue surrounding the abdominal aorta and iliac arteries and extending into the retroperitoneum to envelop neighboring structures. Hydronephrosis due to obstruction of ureters is the most common complication of iRPF. Glucocorticoid with or without immunosuppressants or tamoxifen, the mainstay of iRPF treatment, usually brings good response. Nevertheless, in some conditions, the obstruction of ureters remains unresolved with the treatment of all these medications. One of the reasons lies in the innate feature of the fibroinflammatory tissue. The proliferation of fibrosis tissue in addition to inflammation in the mass was associated with insufficient response to immunosuppressive therapies. Pirfenidone, an anti-fibrosis agent, has been successful in treating pulmonary fibrosis and renal fibrosis. Therefore, it is rationale to assume the effectiveness of pirfenidone in the treatment of iRPF. In the current article, we report a 61-year-old Chinese man with iRPF who responded well to pirfenidone.

Retroperitoneal Fibrosis: Still a Diagnostic Challenge

Retroperitoneal fibrosis (RPF) is a rare fibroinflammatory disorder usually involving the abdominal aorta and surrounding structures. It is divided into primary (idiopathic) and secondary RPF. Primary RPF can be immunoglobulin (Ig) G4-related disease or non-IgG4-related disease. Recently, there has been a rise in case reports regarding the topic, but awareness about the disease is still far from ideal. Hence, we present the case of a 49-year-old female who had repeated admissions for chronic abdominal pain attributed to chronic alcoholic pancreatitis. She had a medical history significant for psoriasis and surgical history significant for cholecystectomy. Her computed tomography (CT) scans on each admission for the last year showed some signs of RPF, but it was never considered the primary etiology of her chronic symptoms. We also obtained magnetic resonance imaging (MRI) which did not show any underlying malignancy but showed the progression of her RPF. She was started on a steroid regimen, which significantly improved her symptoms. She was diagnosed with idiopathic RPF due to unclear etiology, although her underlying risk factors, including psoriasis, past surgeries, and pancreatitis-associated inflammation, were considered predisposing factors. Idiopathic RPF accounts for more than two-thirds of total cases of RPF. Patients with autoimmune diseases can overlap with other autoimmune disorders. For non-malignant RPF, medical management with 1mg/kg/day steroids is deemed effective. Still, there is a lack of prospective trials and consensus for guidelines on treating RPF. The follow-up involves laboratory tests, including erythrocyte sedimentation rate, C-reactive protein, and CT or MRI in an outpatient setting to identify treatment response and relapse. There is a need for more streamlined guidelines to diagnose and manage this disease.

Successful therapy of retroperitoneal fibrosis due to IgG4-related disease with rituximab, cyclophosphamide and glucocorticoids followed by maintenance therapy wit ritutixmab

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, which can lead to acute renal failure and, in the long term, to varying degrees of chronic kidney disease. Common symptoms at onset include lower back, abdominal or flank pain, and constitutional symptoms such as malaise, fever, and anorexia and weight loss. Pain is frequently referred to the hip, to the groin and to the lateral regions of the leg, with nocturnal exacerbations, and typically does not modify with position. We report a case of 56 year-old male with recurrent lower back pain and lower abdominal pain. Contrast-enhanced computed tomography and was suggestive of retroperitoneal fibrosis and unilateral ureteral occlusion. Histologic examination with immunohistochemical staining for IgG4 demonstrate IgG4-related retroperitoneal fibrosis. Therapy was started with prednison 1 mg/kg, but the tolerance of this dose was poor. Therefore the therapy was switched to combination of rituximab 375 mg/ m2 on day 1, cyclophosphamide 300 mg/m2 mg infusion and dexamethasone 20 mg total dose infusion on day 1 and 15 in 28 days cycle. FDG-PET/CT control in fourth month showed residual accumulation of FDG in retroperitoneal fibrotic mass, and therefore the therapy was prolonged to 8 month. The subjective symptoms of this diseases disappeared in the 8th month. Then the maintenance therapy, administration of rituximab in 6 month interval, was started. The activity of this disease be further evaluated by FDG-PET/CT imagination. Glucocorticoids are considered the cornerstone of therapy. The use of other immunosuppressive agents, including cyclophosphamide, azathioprine, methotrexate, mycophenolate mofetil and biological agents such as rituximab, tocilizumab and infliximab and sirolimus have been reported as a valuable option mostly in case reports, cases series and small studies. This agents allowed to reduce cumulative dose of glucocorticoids and its adverse effects. Therefore in our patients we preferred combination of rituximab cyclophosphamide s dexamethasone with lover dose of prednisonem. This combination is preferable for patients who cannot tolerate glucocorticoids or who are likely to suffer from significant glucocorticoids -related toxicity.

Intense 68 Ga-Pentixafor Activity in Idiopathic Retroperitoneal Fibrosis

ABSTRACT

A 52-year-old man was admitted to our hospital with lower abdominal and low back pain, and abdomen CT at an outside hospital presented a retroperitoneal mass with left urinary tract obstruction and hydronephrosis. In 68 Ga-pentixafor PET/CT, the retroperitoneal mass showed intense radioactivity. Subsequently, the patient underwent biopsy of the retroperitoneal mass. The pathological examination showed only fibrous tissue without tumor cells. The patient was finally diagnosed with idiopathic retroperitoneal fibrosis. Our case demonstrated that idiopathic retroperitoneal fibrosis had intense uptake of 68 Ga-pentixafor.

Decreased absolute number of peripheral regulatory T cells in patients with idiopathic retroperitoneal fibrosis

Objective

In order to determine whether the immune balance of T helper 17(Th17)/regulatory T(Treg) is related to the pathogenesis of idiopathic retroperitoneal fibrosis (IRPF), we analyzed the differences in peripheral blood lymphocytes, CD4+T cell subsets and cytokines between patients with IRPF and healthy people to clarify the CD4+T cell subsets, especially Treg cell subsets, and the role of cytokines in the pathogenesis of IRPF.

Methods

This study included 22 patients with IRPF, 36 patients with IgG4-related diseases (IgG4-RD) without retroperitoneal fibrosis (RPF), and 28 healthy controls. The absolute numbers and percentage of peripheral blood lymphocyte subsets and CD4+T cell subsets in each group were detected by flow cytometry, and the serum cytokine level was detected by flow cytometric bead array (CBA).

Results

Compared with the healthy group, the absolute value of B cells in peripheral blood of IRPF patients was significantly decreased, and T, natural killer (NK), CD4+ and CD8+ were not significantly abnormal. The absolute numbers of Th2 cells were lower than healthy group(p=0.043). In particular, the absolute numbers of Treg cells were significantly lower than healthy group(p<0.001), while the absolute numbers of Th17 cells increased(p=0.682). Th17/Treg was significantly higher than healthy group (p< 0.001). Cytokine analysis showed that the level of interleukin (IL)-4 in IRPF patients was higher than healthy group(p=0.011), IL-6, IL-10, IL-17, TNF-α and IFN-γ were significantly higher than healthy group (all p<0.001). Receiver operating characteristic (ROC) curves showed that IL-10 and TNF-α could distinguish bilateral ureteral dilatation in IRPF patients, with areas under the ROC curve (AUCs) of 0.813 (95% CI:0.607-1.000, p=0.026) and 0.950 (95% CI:0.856-1.000, p=0.001), respectively. IL-6 could distinguish bilateral ureteral obstruction, with an AUC of 0.861 (95% CI: 0.682-1.000, p=0.015).

Conclusions

Our study showed that IRPF patients had reduced Treg cells and indeed had Th17/Treg imbalance, which may be related to the pathogenesis of the disease. The levels of IL-6, IL-10 and TNF-α appear to be associated with the progression of IRPF.

Idiopathic retroperitoneal fibrosis with endometrial cancer: a case report and literature review

Background

Retroperitoneal fibrosis is a rare disease characterized by chronic nonspecific inflammation, which leads to clinical compression manifestations of retroperitoneal organs especially ureter. Approximately 70 percent of retroperitoneal fibrosis cases are idiopathic which has no clear etiology. This study reported a rare case of a 48-year-old woman presented with idiopathic retroperitoneal fibrosis and endometrial cancer.

Case presentation

A 48-year-old woman presented with irregular vaginal bleeding without abdominal pain, bloating or discomfort. The patient was diagnosed iRPF after splenectomy 13 years ago. Then she took prednisone for 2 years and took tamoxifen for about 11 years. She stopped taking the medication from October 2019 to May 2020 and then started taking tamoxifen again until November 2020. Two weeks after she stopped taking tamoxifen, she presented with irregular vaginal bleeding. Gynecological ultrasound revealed a thick endometrium with uneven echo enhancement and blood flow signals. Then diagnostic curettage was performed with pathological examination showed endometroid carcinoma. Later, the patient was admitted to Peking University Third Hospital for surgery. Preoperative imaging examinations, including CT, MRI, and PET/CT, all showed pelvic enlarged lymph nodes and they were highly suspected to have lymph node metastasis. The patient underwent laparoscopic surgical staging and enlarged lymph nodes in the pelvic and aortic regions were removed. Finally, the pathology confirmed that endometrioid adenocarcinoma and fibrosis, but there was no tumor infiltration in these enlarged lymph nodes. The patient is now in good condition.

Conclusion

This case report stressed the difficulty to distinguish between lymph node metastasis and inflammatory hyperplasia by common imaging methods. Due to increased surgical difficulty among retroperitoneal patients, lymphadenectomy should be carefully evaluated to avoid additional surgical complications and over-treatment.

Circumferential Fibrosis of the Ascending Aorta After COVID Infection

After recovering from severe COVID-19 infection, 2 women presented with chest pain. Computed tomographic angiography suggested acute ascending aortic dissection. At operation in both patients, the ascending aorta was encased in dense fibrous tissue, within which were focal collections of mononuclear cells, including many plasma cells. There was no entry tear or dissection. Such findings we have not encountered previously, and PubMed search of “periaortic fibrosis and COVID-19” yielded no similar cases or possible relation.

Management of retroperitoneal fibrosis with endovascular aneurysm repair in patients refractory to medical management

Background

Early diagnosis and treatment of under-recognized retroperitoneal fibrosis (RPF) are essential before reaching the poorly responsive fibrotic stage. Although most patients respond to medical therapy, relapses and unresponsiveness are common. However, open surgery in medically resistant patients is associated with major adverse clinical events.

Methods

This is a single-centre longitudinal study of optimal medical therapy (OMT) vs. endovascular aneurysm repair (EVAR) in patients presenting with RPF to our tertiary referral vascular centre. Out of 22,349 aortic referrals, we performed 1,555 aortic interventions over twenty years. Amongst them, 1,006 were EVAR, TEVAR and BEVAR. Seventeen patients (1.09%) had documented peri-aortic RPF.

Results

Out of the 17 RPF patients, 11 received OMT only, while 6 underwent EVAR after the failure of OMT. 82% (n = 14) were male, and the median follow-up was 62.7 months (IQR: 28.2–106). Nine (52%) had immunoglobulin G4-related disease (4 OMT vs. 5 EVAR). EVAR patients had 100% technical success without perioperative mortality. Furthermore, all the EVAR patients were symptom-free following the intervention. Pre-operative aortic RPF index (maximum peri-aortic soft tissue diameter/maximum aortic diameter) was higher in the EVAR than in OMT. However, there was a significant decrement in the aortic RPF index following EVAR (P = 0.04).

Conclusion

We believe that when optimal medical therapy fails in RPF, EVAR provides a promising outcome. Further studies are recommended to establish the role of endovascular repair.

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.

Mixed connective tissue disease and idiopathic retroperitoneal fibrosis: A rare but important association

Idiopathic Retroperitoneal fibrosis (RPF) is a fibro-inflammatory disease. In patients with known mixed connective tissue disease (MCTD) it has rarely been described. Our case illustrates a unique presentation of RPF in a patient with MCTD. We emphasise possible links between the two disease processes and the high level of clinical suspicion required to make a diagnosis.

The contribution of the immune system to genitourinary fibrosis

Fibrotic diseases of the genitourinary tract are devastating and incompletely understood pathologies. These diseases include urethral and ureteral strictures, retroperitoneal fibrosis, and Peyronie's disease. They can contribute to obstructive uropathy and sexual dysfunction. Poor understanding of the pathophysiology of these diseases severely limits our ability to prevent and treat them. Genitourinary fibrotic diseases likely represent related pathologies that share common underlying mechanisms involving wound healing in response to injury. These diseases share the common feature of extracellular matrix abnormalities-such as collagen deposition, transforming growth factor-β accumulation, and dysregulation of collagen maturation-leading to abnormal tissue stiffness. Given the association of many of these diseases with autoimmunity, a systemic pro-inflammatory state likely contributes to their associated fibrogenesis. Herein, we explore the immunologic contribution to fibrogenesis in several fibrotic diseases of the genitourinary system. Better understanding how the immune system contributes to fibrosis in these diseases may improve prevention and therapeutic strategies and elucidate the functions of immunologic contributors to fibrosis in general.

Retroperitoneal fibrosis, a rare entity with urorenal and vascular subtypes - preliminary data

Introduction

Retroperitoneal fibrosis (RPF) is a rare disease associated with the formation of hard inflammatory and fibrous tissue in the retroperitoneum. Taking into consideration the fact that RPF is a rare disease with different subtypes, we compared the basal clinical and biochemical characteristics of the vascular and urorenal subtypes.

Patients and methods

From January 2005 until December 2021, 27 patients were identified as vascular subtype (18 males) and 11 as urorenal subtype (9 males).

Results

Patients with a primary urorenal origin had significantly worse kidney function as reflected by serum creatinine and eGFR (both p < 0.001); they also had higher serum cholesterol (p < 0.01). Hypertension, diabetes, hyperlipidemia and nicotinism were significantly more prevalent in vascular subtype (all p < 0.001).

Conclusion

Vascular subtype is more prevalent in our study with more cardiovascular risk factor present. Due to the diversity of symptoms, diagnosis of RPF becomes a challenge for specialists as well as therapy.

An international patient-centred study of retroperitoneal fibrosis

BACKGROUND

The impact that rare chronic disorders, such as retroperitoneal fibrosis (RPF), can have on the physical and psychological aspects of a patient's health is poorly understood. Patient-related outcome measures and experiences provide a unique opportunity to understand the impact rare chronic disorders have on a patient's life as well as allowing healthcare providers to compare and improve performance.

AIM

To understand the physical and psychosocial impact that RPF has upon peoples' lives.

DESIGN

An international online questionnaire was therefore created to gain insights into how patients with RPF, a rare fibro-inflammatory condition, viewed their health and experiences.

METHODS

An international online questionnaire comprising 62 questions/free text options, was designed in collaboration with two patient advocates and the multi-disciplinary Renal Association Rare Disease Registry (RaDaR) RPF Group the questionnaire was anonymous and freely accessible on a GOOGLE Form online platform for 6 months.

RESULTS

A total of 229 patients from 30 countries across 5 continents responded. Four key issues were identified; (i) pain; (ii) therapy-related side effects; (iii) lack of informed doctors/information about their condition and its management; and (iv) psychological burden. Variations in diagnosis and management are highlighted with 55% undergoing a biopsy to reach a diagnosis of RPF; 75% of patients underwent a further interventional procedure with 60% concurrently treated medically.

CONCLUSION

This study will guide further development of clinical and academic multi-disciplinary activity and shows the importance of trying to understand the impact of rare chronic disorders on the physical and psychological aspects of a patient's health.

The Role of IgG4 in Autoimmunity and Rheumatic Diseases

The distinguishing of the IgG4-related disease (IgG4-RD) from among other rheumatic diseases has brought attention to the IgG4 subclass of immunoglobulins. It is the least numerous subclass among immunoglobulins G. In general, IgG4 is considered to be non-inflammatory and tolerance inducing, due to its unique structure. However, in IgG4-RD this antibody plays a pathogenic role in activation of the fibrinogenesis and of the inflammatory process; there are also suggestions that it may be a marker of an abnormal inflammatory response. The importance of IgG4 for the pathogenesis of allergic diseases, with a vital role of its ratio to immunoglobulin E (IgE/IgG4 ratio), has been known for years. The role of IgG4 in the course and pathogenesis of rheumatic diseases is still being researched and is not yet fully understood. Increased IgG4 levels have been revealed in rheumatoid arthritis, although no clear link between this phenomenon and disease activity has been demonstrated. There are articles on the potential importance of IgG4 concentration (of both elevated and decreased serum levels) in Sjogren’s syndrome. Additionally, anti-nuclear IgG4 antibody significant titers have been detected in SLE patients, and it has been suggested that the effect of these antibodies on complement consumption and the production of proinflammatory cytokines may play a role in inhibiting the progression of SLE. IgG4 plays a role in autoimmune diseases other than rheumatic diseases, such as pemphigus, bullous pemphigoid, idiopathic membranous glomerulonephritis, or myasthenia gravis, but also in helmints infections. Research shows the importance of IgG4 in malignancy of neoplasms. Melanoma cells are known to stimulate IgG4 production through a modified Th2-based inflammatory response. The role of this immunoglobulin in cholangiocarcinoma is also considered as possible. The aim of this review article is to discuss the current knowledge of IgG4 not only from the perspective of the IgG4-RD but also from a point of view of other autoimmune diseases with particular emphasis on rheumatic diseases.

The contribution of oncovascular surgery in a young patient with idiopathic retroperitoneal fibrosis

Surgical resection remains the cornerstone for the treatment of oncological disease. When a critical arterial or venous structure is involved in a tumor mass, successful relief of symptoms and long-term oncological control are achieved through careful preoperative planning by an interdisciplinary team that necessarily includes a vascular surgeon. We describe the involvement of a vascular surgeon in the oncology of a 22-year-old woman, who is diagnosed with idiopathic retroperitoneal fibrosis.

Imatinib-induced retroperitoneal fibrosis in a child with chronic myeloid leukemia: a case report

A 12 year old boy with chronic myeloid leukemia (CML) presenting with bilateral pitting pedal edema and abdominal distension after about 41 months of imatinib therapy and was diagnosed to have retroperitoneal fibrosis (RPF) based on imaging and biopsy findings. He was found to have bilateral hydroureteronephrosis needing double-J stenting to the more severely affected right ureter. Imatinib was briefly interrupted and restarted later due to rising transcript levels and unavailability of other alternatives at that time which was later substituted by dasatinib once generic versions became available. Child remains asymptomatic after 18 months of DJ stenting. RPF is a rare complication of imatinib this being the second case reported in the literature.

Retroperitoneal fibrosis is still underdiagnosed entity with poor prognosis

BACKGROUND

Retroperitoneal fibrosis (RPF) is a rare disease characterized by the presence of inflammatory and fibrous retroperitoneal tissue that often encircles abdominal organs including aorta and ureters. Data on the incidence of this disease are limited.

SUMMARY

The disease may be idiopathic or secondary to infections, malignancies, drugs or radiotherapy. Idiopathic form is an immune-mediated entity and a part of the broader spectrum of idiopathic diseases termed chronic periaortitis, characterized by a morphologically similar fibroinflammatory changes in aorta and surrounding tissues. Taking into account the dominant symptoms and clinical charac-teristics of patients with periaortitis, two subtypes of disease could be distinguished. Vascular subtype include patients with non-dilated aorta or with inflammatory abdominal aortic aneu-rysm, both with and without involvement of adjacent structures and with numerous risk factors for atherosclerosis. In renoureteral subtype obstructive uropathy manifesting with hydronephro-sis and acute kidney injury is predominant finding. Due to the variety of symptoms, diagnosis of RPF remains challenging, difficult and often delayed. A series of diagnostic tests should be performed, in order to confirm the diagnosis idiopathic RPF. Laboratory work-up include eval-uation of inflammatory indices and immunological studies. A biopsy and histopathological evaluation may be necessary to confirm diagnosis and differentiate the disease. Computed to-mography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) are the modalities of choice for the diagnosis and follow-up of this disease. Management of ureteral obstruction, hydronephrosis, and aortic aneurysms often requires surgical evaluation and treatment. The pharmacological treatment of RPF has been evaluated in a few randomized trials and is mainly based on observational studies. Steroid therapy remains the gold standard of treatment. Key messages: Nowadays multidisciplinary team approach with clinical and diagnos-tic experience in both primary and secondary RPF as well as two major subtypes should be offered. Centers specialized in rare diseases with collaboration with other units and referral sys-tem yield the best possible outcomes.

The association of smoking with immunoglobulin G4-related disease: a case-control study

OBJECTIVE

To evaluate the association between cigarette smoking and the odds of IgG4-related disease (IgG4-RD).

METHODS

We performed a case-control study of patients with IgG4-RD compared in a 1:5 ratio with age-, race- and sex-matched controls. We included cases evaluated at the Massachusetts General Hospital, a hospital within the Mass General Brigham (MGB) System. Controls were identified from the MGB Biobank. Smoking status at the date of IgG4-RD diagnosis or corresponding index date was determined. Conditional logistic regression was used to estimate the association between cigarette smoking and the odds of having IgG4-RD.

RESULTS

There were 234 IgG4-RD cases and 1170 controls. The mean age (59 years), sex (62% male) and race (75% white) were well balanced. IgG4-RD cases were more likely to be current smokers compared with controls [25 (11%) vs 70 (6%); odds ratio (OR) 1.79 (95% CI 1.08, 2.95)]. This association was strongest among female cases [13 (14%) vs 19 (4%);, OR 3.79 (95% CI 1.71, 8.39)] and those with retroperitoneal fibrosis [RPF; 13 (28%) vs 13 (6%);, OR 6.93 (95% CI 2.78, 17.26)] or normal IgG4 concentrations [21 (21%) vs 21 (4%); OR 6.22 (95% CI 3.09, 12.49)]. When RPF cases were excluded, there was no longer an association between current smoking and the odds of having IgG4-RD [12 (6%) vs 57 (6%); OR 0.95 (95% CI 0.49, 1.86)].

CONCLUSION

Being a current smoker is associated with greater odds of having IgG4-RD, especially among women and those with RPF or normal IgG4 concentrations. Current smoking is the first recognized modifiable risk factor for IgG4-RD.

Unique Presentation of Idiopathic Retroperitoneal Fibrosis in a Primary Care Setting

Patients with retroperitoneal fibrosis (RPF), a rare condition, present with nonspecific abdominal pain or flank pain that can be complicated by urologic obstruction and/or vascular compromise. Reporting rare entities that often elude prompt diagnosis will aid clinicians to consider the entity in their differential diagnosis and potentially lead to earlier recognition and appropriate management. Our case emphasizes the importance of not just the diagnosis and treatment of RPF but how to best monitor RPF patients to minimize complications from disease progression or treatment-related adverse events.

Role of Eosinophils in Intestinal Inflammation and Fibrosis in Inflammatory Bowel Disease: An Overlooked Villain?

Eosinophils are leukocytes which reside in the gastrointestinal tract under homeostatic conditions, except for the esophagus which is normally devoid of eosinophils. Research on eosinophils has primarily focused on anti-helminth responses and type 2 immune disorders. In contrast, the search for a role of eosinophils in chronic intestinal inflammation and fibrosis has been limited. With a shift in research focus from adaptive to innate immunity and the fact that the eosinophilic granules are filled with inflammatory mediators, eosinophils are becoming a point of interest in inflammatory bowel diseases. In the current review we summarize eosinophil characteristics and recruitment as well as the current knowledge on presence, inflammatory and pro-fibrotic functions of eosinophils in inflammatory bowel disease and other chronic inflammatory conditions, and we identify research gaps which should be covered in the future.

The Potential Use of Cannabis in Tissue Fibrosis

Fibrosis is a condition characterized by thickening or/and scarring of various tissues. Fibrosis may develop in almost all tissues and organs, and it may be one of the leading causes of morbidity and mortality. It provokes excessive scarring that excels the usual wound healing response to trauma in numerous organs. Currently, very little can be done to prevent tissue fibrosis, and it is almost impossible to reverse it. Anti-inflammatory and immunosuppressive drugs are among the few treatments that may be efficient in preventing fibrosis. Numerous publications suggest that cannabinoids and extracts of Cannabis sativa have potent anti-inflammatory and anti-fibrogenic properties. In this review, we describe the types and mechanisms of fibrosis in various tissues and discuss various strategies for prevention and dealing with tissue fibrosis. We further introduce cannabinoids and their potential for the prevention and treatment of fibrosis, and therefore for extending healthy lifespan.

Association of retroperitoneal fibrosis with malignancy and its outcomes

INTRODUCTION

Retroperitoneal fibrosis (RPF) is characterized by a highly fibrotic retroperitoneal mass and encompasses the idiopathic form and secondary to malignancies. Because we have limited knowledge whether RPF is associated with malignancy, we aimed to investigate the relationship between RPF and malignancy and to compare the characteristics and prognosis of cancers among patients with RPF.

METHODS

Medical records of 111 patients diagnosed as having RPF were reviewed and 38 cases of cancer, confirmed by biopsy, were identified. Standardized incidence ratios (SIRs) were calculated for cancers and stratified according to cancer type and RPF-cancer diagnosis interval. Cancer characteristics and outcomes were compared between RPF-cancer diagnosis intervals.

RESULTS

The average age at RPF diagnosis was 59.2 ± 15.0 years, and 69.4% of the patients were male. The cancer SIRs in patients with RPF relative to age- and sex-matched individuals in the general population was 2.2 (1.6-3.1). SIRs of renal pelvis cancer and multiple myeloma were significantly higher than in the general population. When stratified by RPF-cancer intervals, the SIR for cancer was 9.9 within 1 year of RPF diagnosis, while no significant increase in the SIR was found after 1 year from RPF diagnosis. Cancer stage was more advanced at the time of diagnosis in patients within a 1-year interval for RPF than those with cancer within a >5-year interval, with a correspondingly increased mortality in the former patients.

CONCLUSIONS

RPF was significantly associated with malignancy, particularly those diagnosed within 1 year of RPF diagnosis. Cancer stages at diagnosis were more advanced and the mortality rate was higher in patients within a 1-year interval between RPF and cancer diagnosis than in those with a >5-year interval between diagnoses.

Genetic and Epidemiological Similarities, and Differences Between Postoperative Intraperitoneal Adhesion Development and Other Benign Fibro-proliferative Disorders

Intraperitoneal adhesions complicate over half of abdominal-pelvic surgeries with immediate, short, and long-term sequelae of major healthcare concern. The pathogenesis of adhesion development is similar to the pathogenesis of wound healing in all tissues, which if unchecked result in production of fibrotic conditions. Given the similarities, we explore the published literature to highlight the similarities in the pathogenesis of intra-abdominal adhesion development (IPAD) and other fibrotic diseases such as keloids, endometriosis, uterine fibroids, bronchopulmonary dysplasia, and pulmonary, intraperitoneal, and retroperitoneal fibrosis. Following a literature search using PubMed database for all relevant English language articles up to November 2020, we reviewed relevant articles addressing the genetic and epidemiological similarities and differences in the pathogenesis and pathobiology of fibrotic diseases. We found genetic and epidemiological similarities and differences between the pathobiology of postoperative IPAD and other diseases that involve altered fibroblast-derived cells. We also found several genes and single nucleotide polymorphisms that are up- or downregulated and whose products directly or indirectly increase the propensity for postoperative adhesion development and other fibrotic diseases. An understanding of the similarities in pathophysiology of adhesion development and other fibrotic diseases contributes to a greater understanding of IPAD and these disease processes. At a very fundamental level, blocking changes in the expression or function of genes necessary for the transformation of normal to altered fibroblasts may curtail adhesion formation and other fibrotic disease since this is a prerequisite for their development. Similarly, applying measures to induce apoptosis of altered fibroblast may do the same; however, apoptosis should be at a desired level to simultaneously ameliorate development of fibrotic diseases while allowing for normal healing. Scientists may use such information to develop pharmacologic interventions for those most at risk for developing these fibrotic conditions.

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.

Ergotamine Induced Retroperitoneal Fibrosis

Retroperitoneal fibrosis (RPF) is an uncommon disease characterised by the presence of fibroinflammatory reaction which starts around the infrarenal portion of the abdominal aorta in the retroperitoneum and frequently entrap the ureter causing obstructive uropathy. Approximately, two thirds of the cases are idiopathic, where aetiopathogenesis is not known. Ergotamine-induced RPF, although rare, is considered under secondary group. The fibrogenic process here is thought to be due to serotonergic activity. We report a case of RPF in a young female with obstructive uropathy who had history of long-term ergotamine intake for migraine. Histopathological evaluation revealed different evolving stages of necrotising vasculitis. In addition, the patient has responded to withdrawal of offending drug along with immunosuppressive therapy. We believe, apart from serotonergic activity, ergotamine can lead to RPF through a vasculitic process which has not been reported earlier.

Clinical features of IgG4-related retroperitoneal fibrosis among 407 patients with IgG4-related disease: a retrospective study

OBJECTIVES

IgG4-related disease (IgG4-RD) is recently recognized as a fibro-inflammatory condition featured by tumefactive lesions in multiple organs, and the retroperitoneum is one of the common involved sites. We undertook this study to compare detailed demographic, clinical and laboratory characteristics of IgG4-RD patients with retroperitoneum lesion (IgG4-RD RPF+) and retroperitoneum free IgG4-RD (IgG4-RD RPF-) in a large cohort.

METHODS

We carried out a retrospective review of the medical records of 407 cases of IgG4-RD diagnosed at Peking University People's Hospital between March 2009 and May 2019.

RESULTS

Among 407 patients, 58 had retroperitoneum affected. As compared with IgG4-RD RPF- patients, IgG4-RD RPF+ patients showed older age at disease onset and diagnosis. IgG4-RD RPF+ group involved more male patients. In terms of organ involvement, IgG4-RD RPF+ group was more frequently presented with kidney involvement, while salivary gland, lacrimal gland and pancreas were more prominent in the IgG4-RD RPF- group. In addition, the CRP, ESR level and creatinine level were significantly higher in IgG4-RD RPF+ patients, and hypocomplementemia were more common in this group.

CONCLUSION

We have revealed demographic, clinical and laboratory differences between IgG4-RD RPF+ and RPF- patients, which indicated potential differences in pathogenesis and important implications for the diagnosis and management of these two phenotypes.

The Resonance and the Allium ureteral stents in the treatment of non-malignant refractory ureterostenosis

Background

Refractory non-malignant ureterostenosis is challenging to treat. The experience to treat the stenosis primarily cause by retroperitoneal fibrosis with the Resonance and Allium metallic stent is still limited. We aim to evaluate the efficacy and safety of these two stents and provide alternative treatment options.

Methods

A retrospective study was conducted for patients with non-malignant ureterostenosis and treated with the Resonance and Allium stents from March 2011 to September 2020 in our department. The efficacy was evaluated by the change of serum creatinine, glomerular filtration rate (GFR), the proportion of GFR of the affected side and hydronephrosis grade. The safety was evaluated by postoperative presence of moderate or severe overactive bladder (OAB), recurrent urinary infection, pain, stent displacement, encrustation and re-obstruction.

Results

33 patients were eligible for the study, including 18 cases treated by the Resonance stents and 15 patients treated by the Allium stents. The patients of two groups had similar age and gender proportion. The cause of ureterostenosis was mainly retroperitoneal fibrosis in both groups but the Resonance group had more idiopathic cases. Follow-up time was significantly longer in the Resonance group than the Allium group (36.2 ± 24.0 vs 9.4 ± 5.0 months, p < 0.001). Both groups showed improvement or maintenance of serum creatinine level, GFR, the GFR proportion of the affected side and hydronephrosis grade after treatment. The Resonance group presented significant higher incidence of moderate or severe OAB, recurrent urinary infection and pain, while the Allium group showed significant more cases of re-obstruction.

Conclusion

Both the Resonance and Allium stent can relieve the non-malignant refractory ureterostenosis effectively. The Resonance stent may cause more irritable symptoms while the Allium stent may have a higher rate of re-obstruction. The long term efficacy and safety of the Allium stent in treating non-malignant refractory ureterostenosis requires further study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-021-00815-6.

IgG4-Related Disease Retroperitoneal Fibrosis: An Unusual Cause of Low Back Pain

IgG4-related disease (IgG4-RD) is a cluster of rare fibroinflammatory diseases that more commonly affect organs such as major salivary glands, biliary tree, periorbital tissues, kidneys, lungs, lymph nodes, retroperitoneum, and less frequently, meninges, aorta, prostate, thyroid gland, pericardium, and the skin. The clinical picture mainly depends on the affected organ and the effects on the surrounding organs, however, the histopathologic findings are very similar regardless of the organ affected. Most patients have a subclinical presentation of the disease and the only clinical manifestation is related to the anatomic location of the disease, whereas some patients may have constitutional symptoms such as weight loss and are often misdiagnosed as having other pathologies (i.e., malignancies, other inflammatory conditions, etc.). Up to 40 percent of patients can have symptoms of allergy or asthma. Patients often have diseases confined to one organ but multiorgan involvement is not uncommon. Patients with multiple organs involvement can have an elevation of up to 30-40 upper limit of normal serum IgG4 concentration; patients with fewer organ involvement can have normal serum IgG4 concentration despite histopathologic findings of the disease. 

Idiopathic retroperitoneal fibrosis (RPF) is a commonly encountered subtype of IgG4-RD. Idiopathic retroperitoneal fibrosis accounts for approximately 70 percent of cases and can be divided into IgG4-RD and non-IgG4-RD. Most cases of RPF are incidental findings on radiology studies but should be suspected in any patients complaining of back pain and flank pain, with new-onset kidney dysfunction.

Splenic abscess diagnosed following relapsing sterile peritonitis in a peritoneal dialysis patient: A case report with literature review

Peritoneal dialysis (PD)-related peritonitis is sometimes complicated with other infections; however, few cases of splenic abscess have been reported. We present the case of a 64-year-old PD patient with complicated splenic abscesses diagnosed following relapsing sterile peritonitis. After PD induction, he presented with turbid peritoneal fluid and was diagnosed with PD-related peritonitis. A plain abdominal computed tomography (CT) did not reveal any intra-abdominal focus of infection. After empiric intravenous antibiotics, the peritoneal dialysate was initially cleared, with a decrease in dialysate white blood cells (WBC) to 20/µL. However, WBC and C-reactive protein (CRP) levels remained elevated. A contrast-enhanced abdominal CT showed two areas of low-density fluid with no enhancement in a mildly enlarged spleen, making it difficult to distinguish abscesses from cysts. Due to relapsing sterile peritonitis, we performed an abdominal ultrasonography, and suspected splenic abscesses due to rapid increase in size. Repeated imaging tests were useful in establishing a diagnosis of splenic abscesses. Considering the persistent elevation of WBC and CRP levels, imaging findings, and episodes of relapsing peritonitis, we comprehensively formed the diagnosis, and performed a splenectomy as a rescue therapy. We should consider the possibility of other infectious foci with persistent inflammation after resolving PD-related peritonitis.

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.

Into Clinical Practice: Diagnosis and Therapy of Retroperitoneal Fibrosis

PURPOSE OF THE REVIEW

We aim to review the most relevant diagnostic features and treatment options of retroperitoneal fibrosis, in order to provide a useful guide for clinical practice.

RECENT FINDINGS

The recent literature highlights the role of imaging studies such as computed tomography, magnetic resonance imaging and positron emission tomography as useful tools for the diagnosis of retroperitoneal fibrosis, with retroperitoneal biopsy being reserved to atypical cases. The treatment approach is mainly conservative and is based on the use of medical therapies plus urological interventions. Medical therapies essentially comprise glucocorticoids and immunosuppressants-either traditional or biological agents such as rituximab. Surgical ureterolysis is only left for refractory cases. Recent findings in retroperitoneal fibrosis highlight the possibility of a non-invasive diagnostic approach and a conservative treatment strategy.

[SIGNIFICANCE OF IgG4 IN IDIOPATHIC RETROPERITONEAL FIBROSIS]

(Objective)Retroperitoneal fibrosis is largely divided into the idiopathic and secondary types. Some idiopathic cases include IgG4-related diseases, which are often similar to malignant diseases, such as lymphoma and sarcoma. The diagnostic criteria for IgG4-related disease are used and pathologic examination is necessary for a definitive diagnosis of IgG4-related retroperitoneal fibrosis. The first choice of treatment for IgG4-related retroperitoneal fibrosis is steroid administration, but no consensus has been established regarding its dose and tapering schedule. We investigated the significance of IgG4 in diagnosis and treatment of idiopathic retroperitoneal fibrosis. (Patients and methods)We examined 14 cases diagnosed as idiopathic retroperitoneal fibrosis between April 2013 and March 2019. Serum IgG4 was measured at the time of diagnosis in 13 cases, and changes over time in serum IgG4 before and after the induction of steroid therapy were measured in 6 cases. Computed tomography-guided biopsy was performed on 4 cases. (Results)Of all cases, 1 patient was diagnosed as IgG4-related retroperitoneal fibrosis and 5 patients were classified as possible group. Ten patients were administered steroid therapy. Percutaneous nephrostomy tube was placed in 3 patients and was removed in 2 of these patients after steroid therapy. The serum high levels of IgG4 were confirmed in all 4 patients who were classified into the possible group and who were treated with steroids. (Conclusion)Although histologic examination is necessary for the diagnosis of retroperitoneal fibrosis, tissue collection by open or laparoscopic surgery is highly invasive. CT-guided biopsy may be useful in high-risk cases, such as elderly patients on anticoagulation. After excluding other diseases in high-risk cases, response to empiric steroid therapy may be diagnostic. In the possible group, changes in serum IgG4 levels may reflect the disease condition and might be useful in determining the maintenance dose of steroids.

Immunoglobulin G-4-Related Retroperitoneal Fibrosis

Retroperitoneal fibrosis is caused by the replacement of normal retroperitoneal tissue with fibrosis. The majority of the cases are idiopathic, but some secondary causes include malignancy, infection, drugs, and radiotherapy. Immunoglobulin G-4 (IgG-4) related disease is a relatively newer disease and one of the rarer causes of retroperitoneal fibrosis. It usually involves the pancreas, lungs, kidneys, aorta lacrimal and salivary glands, or extrapancreatic bile duct. Elevated serum IgG-4 is the biomarker of the disease and its levels correlate with disease activity. High-dose glucocorticoid is the treatment of choice.

Treatment Response to Idiopathic Retroperitoneal Fibrosis-associated Hydronephrosis With a Focus on IgG4/IgG3 Serum Concentration Ratio

OBJECTIVE

Hydronephrosis, a common complication of idiopathic retroperitoneal fibrosis (iRPF), may lead to poor renal outcomes unless resolved in a timely manner IgG4-related diseases characterized by elevated serum IgG4 levels are responsible for a few iRPF cases However, the underlying immunologic features of most iRPF cases have not been clearly defined, and these cases exhibit varied responses to medical treatment Thus, we investigated the predictive factors for hydronephrosis-associated outcomes among iRPF patients.

METHODS

We retrospectively included 18 iRPF patients with hydronephrosis in a tertiary referral hospital from 2012 to 2019 Hydronephrosis improvement was assessed on images taken 6 months after diagnosis Categorical variables were compared using chi-square or Fisher's exact test Continuous variables were compared using Mann-Whitney U-test.

RESULTS

On follow-up images, 8 patients (444%) showed an improvement in hydronephrosis Patients with improvement more frequently had reverse serum IgG4/IgG3 ratio (875% vs 30%, p=0025), abdominal aorta involvement (875% vs 30%, p=0025) and glucocorticoid treatment administration (875% vs 30%, p=0025) than those without improvement The proportion of elevated serum IgG4 level did not differ between the two groups Even in the 14 cases with normal serum IgG4 levels, reverse serum IgG4/IgG3 ratio was more frequently observed in patients with improvement than in those without improvement (833% vs 125%, p=0026).

CONCLUSION

The reverse serum IgG4/IgG3 ratio was associated with hydronephrosis improvement in iRPF patients, suggesting it to be a suitable serologic marker for predicting favourable responses to glucocorticoid treatment.

Bilateral Hydronephrosis From Retroperitoneal Fibrosis

Retroperitoneal fibrosis (RPF) is a rare condition characterized by fibroinflammatory tissue infiltrating and compressing retroperitoneal structures. While mostly idiopathic (idiopathic retroperitoneal fibrosis or IRF), RPF is frequently associated with certain drugs, infections, and malignancies. It is thought to be immune-mediated because of response to steroids and RPF is commonly seen with other autoimmune diseases, especially IgG4-related disease (IgG4-RD). IRF is also a part of the chronic aortitis syndromes and the presence of aortic aneurysms is another characteristic of this disease. A 63-year old woman presented with left-sided flank pain. Computed tomography (CT) scan showed left hydronephrosis from compression of the ureter by a retroperitoneal mass. A thoracoabdominal aneurysm was also noted. A [¹⁸F]- fluorodeoxyglucose positron emission tomography (FDG-PET) scan showed hypermetabolism in the mass, with no abnormally increased activity noted elsewhere. Within four months, the mass enlarged to involve the right ureter as well, leading to right hydronephrosis. She required bilateral ureteral stents and aneurysm repair. Biopsy of the mass showed dense fibrosis with a mononuclear cell infiltrate. The histology of the aneurysm specimen showed chronic periaortic inflammation. Laboratory investigations were significant for elevated C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), with no evidence of monoclonal gammopathy. She was referred to the rheumatology clinic to receive steroid treatment for IRF. IRF commonly involves the ureters and is diagnosed on CT scans during a workup for obstructive uropathy. The treatment is high dose steroids, while in resistant cases, other immunosuppressants have been used. The presentation of a patient with IRF can commonly mimic that of urinary calculi and malignancy. While rare, IRF should not be forgotten when evaluating a patient for obstructive uropathy.