Idiopathic Retroperitoneal Fibrosis

IgG4-related disease and other fibro-inflammatory conditions

IgG4-related disease (IgG4-RD) is a fibro-inflammatory disorder usually characterized by multi-organ involvement. Its pathogenesis is complex and involves genetic and environmental factors, while immune responses usually mediate organ damage and promote fibrosis, which is a key feature of the disease. IgG4 responses, however, are not exclusive to IgG4-RD and can be encountered in other diseases with phenotypes that partially overlap that of IgG4-RD. Although IgG4-RD has clinical and histological hallmarks, the lack of validated diagnostic criteria often makes the diagnosis challenging, requiring a multi-dimensional approach that integrates clinical, radiological and serological data. The present Review covers recent advances in the understanding of disease drivers and its clinical phenotypes, mainly focusing on the differential diagnosis with potential IgG4-RD mimickers, namely histiocytoses, lymphoproliferative disorders, systemic vasculitides and other immune-mediated conditions. The Review also provides a schematic approach to IgG4-RD treatment, including a brief overview of glucocorticoid-sparing agents and emerging therapies, from B cell-depleting monoclonal antibodies to cytokine-targeting drugs, the majority of which are currently under investigation in randomized clinical trials.

Predictors of irreversible renal dysfunction in patients with idiopathic retroperitoneal fibrosis

OBJECTIVES

Idiopathic retroperitoneal fibrosis (iRPF) can lead to irreversible kidney damage. This study aimed to investigate predictors of irreversible renal dysfunction in patients with iRPF.

METHODS

Eighty-three patients with newly diagnosed iRPF were enrolled between January 2010 and September 2022 at Zhongshan Hospital of Fudan University, including 60 in the training set and 23 in the validation set. They were regularly contacted or followed up via outpatient examinations by specialist doctors, who documented their condition and treatment progress. Predictors of irreversible renal dysfunction were identified using univariate and multivariate regression, logistic model, and receiver operating curve analyses.

RESULTS

In the training set, over a median follow-up of 29 months, 16.7% of patients had an estimated glomerular filtration rate (eGFR) of <60 ml/min/1.73 m2 at the last follow-up, and 25% had hydronephrosis or required prolonged double-J stents. A prognostic score was developed by assigning 1, 1, and 2 points for peripheral CD19+ B cells <9.3%, serum creatinine (sCr) ≥120 µmol/L, and no response at 6 months, respectively. A score of ≥2 for predicting irreversible renal dysfunction had sensitivity and specificity of 100% and 92%, respectively. In the validation set, 21.7% of patients suffered from irreversible renal dysfunction. The sensitivity and specificity for predicting irreversible renal dysfunction were 100% and 94.4%, respectively.

CONCLUSIONS

A prognostic score based on factors including CD19+ B cells <9.3% and sCr ≥120 µmol/L at baseline, and no response at 6 months, is suitable for predicting irreversible renal dysfunction in iRPF.

Multimodality imaging review of retroperitoneal fibrosis

Retroperitoneal fibrosis (RPF) is a rare fibroinflammatory disease with idiopathic and secondary causes. Idiopathic disease is more common and is believed to be immune mediated; associations with autoimmune diseases and/or inflammatory disorders such as IgG4 related disease are often present. Common complications include hydronephrosis and venous stenosis and/or thrombosis. Due to its nonspecific clinical presentation, imaging is vital for diagnosis; in addition, imaging may help distinguish idiopathic from secondary causes and can aid in distinguishing early/active disease from chronic/inactive disease. Magnetic resonance imaging is the preferred imaging modality to stage and monitor the disease, though CT and PET/CT imaging may also be of value. While the imaging findings can overlap with other diseases, there are some characteristic findings which can favor RPF. However, a biopsy is needed for a definitive diagnosis.The following article discusses the clinical features, imaging appearances across modalities, associated complications, potential diagnostic pitfalls, and treatment approaches for RPF. The role of advanced imaging techniques, such as diffuse weighted imaging and 18F-FDG PET/MRI, in the evaluation of RPF will also be included.

Treatment approaches for idiopathic retroperitoneal fibrosis: a systematic review with meta-analysis

BACKGROUND

Currently, there is no standard therapy for idiopathic retroperitoneal fibrosis, so a systematic review was undertaken to assess the effectiveness of different treatment approaches.

METHODS

A comprehensive search of English and German literature from 1980 to 2021 was conducted using PubMed, Embase, and PreMedline. To be included, studies must have had a minimum of two patients employing the same treatment approach and reporting relevant treatment outcomes. A meta-analysis with a subgroup analysis was conducted for the primary outcomes "regression of fibrosis," "freedom from ureteric stents" and "relapse rate," and the secondary outcome "clinical improvement." The lack of homogeneous data prevented a subgroup analysis for the primary outcome "improvement in renal function."

RESULTS

The search resulted in a total of 3818 articles, of which 108 were selected for qualitative analysis involving a total of 1408 patients. For the meta-analysis 83 studies were included involving 1044 patients. The summary effect size of the outcomes "regression of fibrosis," "freedom from ureteric stent" and "clinical improvement" was high with values between 80-97.9%. The summary relapse rate across studies was 18.1%. Subgroup analysis revealed no statistically significant differences in the effectiveness of treatment approaches for the outcomes "regression of fibrosis" (QM = 2.72, p = 0.74), "freedom from ureteric stent" (QM = 7.21, p = 0.13), "relapse rate" (QM = 11.34, p = 0.08) and "clinical improvement" (QM = 9.54, p = 0.15).

CONCLUSIONS

Considering the lack of clear evidence indicating that one drug is more effective than the other, the treatment choice should depend on factors such as the potential side effects of different drug therapies, patient comorbidities, and clinician expertise. The review protocol is registered on PROSPERO under the identification number CRD42019115744.

Systemic lupus erythematosus complicated by retroperitoneal fibrosis: A case report and literature review

RATIONALE

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that affects multiple organ systems. Retroperitoneal fibrosis (RPF) is a rare condition characterized by the development of fibrous tissue in the retroperitoneal space. The coexistence of SLE and RPF is extremely uncommon, and this report aims to enhance understanding of this complex relationship.

PATIENT CONCERNS

A 32-year-old woman presented with sudden-onset syncope. Her medical history revealed a 5-year history of SLE, and imaging studies identified a retroperitoneal mass.

DIAGNOSES

A comprehensive diagnostic workup, including magnetic resonance imaging (MRI) and biopsy, confirmed retroperitoneal fibrosis secondary to SLE.

INTERVENTIONS

The patient was treated with high-dose corticosteroids, immunosuppressive therapy, and the biologic agent rituximab.

OUTCOMES

The patient's symptoms markedly improved, and follow-up MRI demonstrated significant regression of the retroperitoneal lesion.

LESSONS

RPF associated with SLE is exceptionally rare. This case underscores the importance of early diagnosis and a coordinated multidisciplinary approach in managing such complex conditions. Glucocorticoid therapy remains the cornerstone of treatment, augmented by immunosuppressants and biologic agents when necessary.

Ormond's Disease - 26 Years of Experience at One Centre

Ormond's disease is a systemic autoimmune disease with serious complications. We present our retrospective analysis of 83 patients diagnosed with and treated for idiopathic retroperitoneal fibrosis (Ormond's disease) in our department from 1997 to 2023. In this retrospective study, we analysed the diagnostic approaches, the clinical history and surgical and immunosuppressive therapies, and their subsequent effects on our patients. Patients with established disease activity were given immunosuppressive treatment, using corticosteroids alone or in combination with azathioprine, in patients with exacerbation of the disease mycophenolate mofetil. Three patients with Ormond's disease and systemic complications (IgG4-related disease) were treated with rituximab. In the entire cohort, 83 patients received immunosuppressive therapy; the next 5 patients did not receive this treatment because they did not present inflammatory activity from the disease. In these 83 patients, computed tomography showed that immunosuppressive treatment resulted in partial or complete regression of the inflammatory infiltrate. Out of the 83 patients, 10 patients experienced disease exacerbation 7 and 24 months after the immunosuppressive treatment was discontinued. The follow-up ranged from 24 months to 26 years.

Outcomes of retroperitoneal fibrosis-related hydronephrosis and its risk factors for poor prognosis: a multi-center retrospective cohort study in Chinese patients

Objective

Retroperitoneal fibrosis (RPF) is a rare disease characterized by the presence of fibroinflammatory tissue that surrounds the abdominal aorta and the iliac arteries and often entraps the ureters. Hydronephrosis is a common complication of RPF, however, its clinical features and outcomes have not been well elucidated.

Methods

A total of 115 RPF-related hydronephrosis patients have been recruited from 9 clinical centers in China since March 2010. They were followed up until death or September 2021, whichever came first.

Results

The mean age at diagnosis was 58.83 ± 12.13 years, and 80 patients (69.57%) were men. The median disease duration was 3.00 (1.00, 9.00) months. Renal impairment was observed in 88.35% of the patients, and 49.57% showed bilateral ureteral involvement. Elevated ESR and CRP were presented in 80.28 and 62.02% of the patients, respectively. Overall, 28.21% (11/39) of the patients had increased IgG4 levels, and 41.38% (12/29) showed positive pathological IgG4 staining (IgG4+/IgG+ ≥ 40% or IgG4+ ≥ 10/HPF). Among them, three patients were diagnosed as IgG4RD. After 60.43 ± 34.53 months of follow-up, 36 patients had poor prognosis, which was associated with severe kidney impairment, bilateral hydronephrosis and inflammation status (elevated ESR and IgG) at diagnosis by case-control study. eGFR and creatinine were independent risk factors after adjusting for all other significant associations (p = 0.002 and p = 0.067, respectively). Glucocorticoid-based therapy could reduce the time of stenting, decrease the need for long-term ureteral stenting/percutaneous nephrostomy (PNS)/ureterolysis, increase the rate of mass shrinkage, and reduce the new requirement of hemodialysis compared to surgery-only strategy for RPF-related hydronephrosis patients in need of renal drainage, but did not reduce new-onset renal atrophy.

Conclusion

Severity of kidney dysfunction and inflammation status were related to the poor prognosis of hydronephrosis induced by RPF. More efficient interventions and strategies are needed to further improve outcomes.

The Enigma of Retroperitoneal Fibrosis: Clinical Implications and Diagnostic and Therapeutic Challenges

Retroperitoneal fibrosis (RPF) is a rare disease with a nonspecific presentation. RPF can be classified into Idiopathic, the most common, or secondary due to malignancy and various medications resulting in chronic inflammation and fibrosis in the retroperitoneum. The complications arise due to the compression of structures in the retroperitoneum. The most common presentations are constitutional symptoms, abdominal pain, and renal insufficiency due to ureteral obstruction. Venous thrombosis or claudication on presentation is rare. Diagnosis and treatment remain challenging due to the lack of standard diagnostic or treatment protocols. Our patient presented with symptoms of acute deep vein thrombosis (DVT) with varices on the abdomen and mild bilateral hydronephrosis. A CT scan revealed a retroperitoneal mass, which was confirmed to be RPF by biopsy. Relevant laboratory tests, including IgG4, were negative. High-dose corticosteroid therapy reduced the inflammatory markers and the size of the retroperitoneal mass.

[Etiological analysis of hydronephrosis in adults: A single-center cross-sectional study]

OBJECTIVE

To investigate the etiological distribution of hydronephrosis caused by upper urinary tract obstruction in adult patients and to improve the diagnostic accuracy for this condition.

METHODS

The clinical information of adult patients with newly diagnosed hydronephrosis in Upper Urinary Tract Repair Outpatient Clinic of Peking University First Hospital from May 2020 to May 2021 were prospectively and continuously collected. Patients with ureteral calculi or upper urinary tract tumor were excluded. A total of 767 patients were involved. The underlying causes of upper urinary tract obstruction were identified by senior urological surgeons according to symptoms, medical history, physical examination, and a range of diagnostic imaging techniques including ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), retrograde pyelography, antegrade pyelography, radionuclide renogram and ureteroscopy.

RESULTS

Among the 767 patients, 359(46.8%) were male and 408(53.2%) were female. The median age of these patients was 37 years (range, 14-84 years). Hydronephrosis was observed at left-sided in 357 cases(46.6%), right-sided in 251 cases(32.7%), and bilateral in 159 cases(20.7%). The causes of hydronephrosis were classified as follows: (1) Non-iatrogenic factors were found in 464 cases (60.5%). These included urinary malformations in 355 cases(76.5%), infection in 29 cases(6.3%), pelvic lipomatosis and/or cystitis glandularis in 23 cases(5.0%), ureteral endometriosis in 18 cases(3.9%), retroperitoneal fibrosis in 15 cases(3.2%), trauma in 7 cases(1.5%) and other non-iatrogenic factors in 12 cases(2.6%). Some of these patients had multiple non-iatrogenic causes. Among the 355 cases with urinary system malformations, 252 cases (71.0%) had ureteropelvic junction obstruction. (2) Iatrogenic ureteral injuries accounted for 210 cases (27.4%), including 112 cases(53.3%) of urological surgical injuries, 51 cases(24.3%) of radiotherapy for malignant tumor related injuries, 34 cases(16.2%) of gynecological and obstetrical surgical injuries, and 13 cases(6.2%) of general surgical injuries. (3) The cause of hydronephrosis remained unknown in 93 cases(12.1%).

CONCLUSION

Hydronephrosis in adults due to upper urinary tract obstruction has a diverse range of causes, with urinary malformations and iatrogenic ureteral injuries being significant contributors. Urological surgeon involved in upper urinary tract reconstruction should be familiar with these potential causes to facilitate accurate diagnosis and effective treatment.

Benign Tumors and Tumor-Like Conditions of Ampulla and Small Intestine: The PathologyOutlines.com Review

Small intestine and ampulla can be involved in a heterogeneous group of benign tumors and tumor-like diseases, potentially mimicking malignant neoplasms. In-depth knowledge of them is critical for practicing pathologists since they represent potential pitfalls in routine diagnostic activity. Such conditions include the following: (1) Brunner gland lesions, including Brunner gland hyperplasia and hamartoma; (2) polyps, such as adenoma, hyperplastic, hamartomatous, and inflammatory; (3) mesenchymal proliferations encompassing inflammatory fibroid polyp, inflammatory myofibroblastic tumor, leiomyomas, lipomas, and lipomatosis of the ileocecal valve; (4) fibrosis-associated diseases, such as idiopathic retroperitoneal fibrosis, reactive nodular fibrous pseudotumor, and sclerosing peritonitis; (5) disorders of lymphatic vessels, including lymphangiectasia and lymphangiomas; and (6) other rare conditions/miscellanea, such as enteritis cystica profunda, intussusception, ischemia, and pneumatosis cystoides intestinalis. This review, inspired by the content of the PathologyOutlines website (https://www.pathologyoutlines.com), aims to provide a reference point in this complex scenario, summarizing the essential histopathological features of all these entities for better addressing routine practice and differential diagnoses.

Multiple Myeloma and Retroperitoneal Fibrosis: A Rare Association Report and Literature Review

Multiple myeloma (MM) is a common hematological malignancy. Autologous hematopoietic stem cell transplantation (auto-HSCT) can significantly improve the prognosis of patients with MM, but a variety of complications may occur after transplantation. Retroperitoneal fibrosis (RPF) is a rare cause of obstructive nephropathy. Because there are no specific symptoms at the time of onset and the course of the disease is often insidious, special laboratory and instrumental examination methods are usually needed to confirm the diagnosis. This article describes the clinical case of a 50-year-old female patient diagnosed with multiple myeloma. She developed postoperative acute kidney injury (AKI) more than 20 days after transplantation and was subsequently diagnosed with retroperitoneal fibrosis. After multidisciplinary collaboration, early transurethral vesicoureteral stent placement was performed, the obstruction was relieved, and her renal function returned to normal. Reports of retroperitoneal fibrosis after multiple myeloma transplantation are relatively rare. This case report advances our understanding of these 2 diseases, and the correlation between MM and RPF warrants further exploration.

Testicular fibrosis pathology, diagnosis, pathogenesis, and treatment: A perspective on related diseases

Testicular fibrosis is a chronic and progressive condition characterized by the excessive deposition of extracellular matrix proteins. This process leads to fibrotic remodeling, damage to testicular tissue, and the irreversible loss of male reproductive function. However, there is currently a lack of comprehensive reviews systematically elucidating the pathology, diagnosis, pathogenesis, and treatment of testicular fibrosis from the perspectives of different related diseases. This review addresses these aspects of testicular fibrosis, with a particular emphasis on elucidating the underlying mechanisms of testicular cells. It provides insights that can be relevant for future research and clinical interventions.

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.