IgG4-related retroperitoneal fibrosis induced by nivolumab and ipilimumab in a patient with non-small cell lung cancer: A case report.

IgG4-related diseases are adverse events that occur after receiving treatment with immune checkpoint inhibitors (ICI). This study reports the first case of IgG4-related retroperitoneal fibrosis after the administration of chemotherapy with nivolumab and ipilimumab (NI therapy). An 80-year-old man developed lower abdominal pain eight months after NI therapy was initiated. Although the primary lesion maintained its reduced size on computed tomography, there was an increase in the soft tissue shadows intensity around the abdominal aorta, bladder, and seminal vesicles, suggesting retroperitoneal fibrosis. Blood tests showed elevated IgG4 levels. Computed tomography-guided biopsy of the retroperitoneum showed B cell-dominant lymphocyte infiltration consistent with IgG4-related retroperitoneal fibrosis and characteristic CD8-positive lymphocyte infiltration, suggestive of the involvement of cytotoxic T cells. Based on the clinical, imaging, and pathological findings, the patient was diagnosed with IgG4-related retroperitoneal fibrosis due to ICI. Immunotherapy discontinuation alone did not result in improvement; therefore, steroid therapy was initiated. In clinical practice, IgG4-related retroperitoneal fibrosis can occur as an immune-related adverse event when administering anti-PD-1 and anti-CTLA-4 antibodies for cancer immunotherapy. Early steroid therapy could be effective in controlling this immune-related adverse event.

Clinical Characteristics of Retroperitoneal Fibrosis Patients at a Tertiary Hospital in Japan.

Retroperitoneal fibrosis (RPF) is a rare cause of hydronephrosis and progressive renal dysfunction with unidentified origin. RPF is categorized into idiopathic RPF with/without immunoglobulin G4 (IgG4)-related disease (IgG4-RD), and secondary RPF. Identifying the underlying cause is challenging and often associated with delayed diagnosis or therapeutic interventions. We investigated RPF's clinical characteristics based on different etiologies and factors that may help distinguish the underlying causes. We analyzed the cases of 49 patients with RPF that was radiographically diagnosed at our institution (2008-2022). The cohort was 77.6% males; 75.5% had idiopathic RPF and 24.5% had secondary RPF. Among the idiopathic patients, 54.1% had IgG4-RD. The patients were likely to have abdominal pain, lower back pain/lumbago, and constitutional symptoms including generalized fatigue and fever. The idiopathic patients were likely to have higher serum IgG4 and IgG levels and lower serum C3 levels compared to secondary RPF. The IgG4-RPF patients were likely to have higher serum IgG4 levels and lower serum C-reactive protein, ferritin, and C3 levels compared to the idiopathic RPF patients without IgG4-RD. These findings might reflect underlying systemic inflammatory responses. Comprehensive laboratory testing, including serum inflammatory markers and immunological panels, is recommended for radiologically diagnosed RPF patients.

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 immunoglobulin G4-related retroperitoneal fibrosis and hypophysitis with antecedent respiratory disease followed by spontaneous remission and recurrence.

A 65-year-old man presented with apparent bronchopneumonia. After treatment with antibiotics, he showed eosinophilia. Computed tomography (CT) imaging revealed bilateral consolidation, ground-glass opacities with nodular consolidations, and pleural effusion. Lung biopsy showed organising pneumonia with lymphoplasmacytic infiltration in the alveolar septa and in the thickened pleura and interlobular septa. All pulmonary abnormalities spontaneously went into remission within 12 months. At 73 years old, a follow-up CT scan revealed small nodules in both lungs and the review of the head CT scan showed thickening of the pituitary stalk in studying prolonged headache. Two years later, he visited the hospital complaining of severe oedema on the lower extremities with high serum immunoglobulin (Ig)G4 186 mg/dl. A whole-body CT scan showed retroperitoneal mass surrounding aortic bifurcation and compressing inferior vena cava, pituitary stalk thickening and gland swelling, and enlarged pulmonary nodules. Anterior pituitary stimulation tests showed central hypothyroidism, central hypogonadism, and adult growth hormone deficiency with partial primary hypoadrenocorticism. Retroperitoneal mass biopsy showed storiform fibrosis and obliterative phlebitis with marked lymphoplasmacytic infiltration with moderate IgG4-positivity. Immunostaining of the former lung specimen revealed dense interstitial infiltration of IgG4-positive cells. These findings indicated metachronous development of IgG4-related disease in lung, hypophysis, and retroperitoneum, according to the recent comprehensive diagnostic criteria of IgG4-related disease. Glucocorticoid therapy ameliorated oedema, on the other hand, unmasked partial diabetes insipidus at the initial dose of the treatment. Hypothyroidism and retroperitoneal mass regressed at 6 months of the treatment. This case warns us that long-term follow-up from prodromal to remission is necessary for the treatment of IgG4-related disease.

IgG4-related disease and isolated retroperitoneal fibrosis: A narrative review.

Retroperitoneal fibrosis (RPF) can occur due to many etiologies and is categorized into idiopathic and secondary. Etiologies of secondary RPF include medications, autoimmune disease, malignancy, and IgG4-related disease (IgG4-RD). Although IgG4-RD usually involves multiple systems synchronically including the pancreas, aorta, and kidneys, it can present with isolated RPF without involvement of other organ systems. Caution must be exercised in these instances as the diagnosis should be confirmed based on specific clinical, radiographic, and histopathologic criteria. Such confirmation can affect the work-up and therapeutic approach as treatment with corticosteroids can lead to remission, both clinically and radiographically.

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.

Usefulness of methotrexate in relapsing idiopathic retroperitoneal fibrosis.

OBJECTIVES: Glucocorticoids are the mainstay for treatment of retroperitoneal fibrosis (RPF), a disease characterised by a periaortic proliferation of fibroinflammatory tissue frequently causing urinary obstruction. The therapeutic approach to patients unsuitable for steroid therapy and to relapsing cases is still undefined. METHODS: In this retrospective single-centre study we evaluated 15 patients with RPF who received second-line therapy with methotrexate (MTX) between January 2011 to December 2019. RESULTS: Fourteen out of 15 patients (93%) showed response to MTX. Two patients experienced relapse: one patient when on MTX therapy (28 months), the other, 58 months after MTX was interrupted. Liver toxicity grade 2 was documented in 2 patients and resolved with temporary dosage reduction. One patient stopped MTX autonomously because of nausea. No severe infections were recorded. CONCLUSIONS: In selected patients with RPF who are intolerant or refractory to steroid single therapy, MTX may be considered as useful and safe second-line treatment.

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.

The Onset of IgG4-related Retroperitoneal Fibrosis under Administration of a TNF Inhibitor in a Rheumatoid Arthritis Patient.

An 80-year-old woman with rheumatoid arthritis during treatment with etanercept, a tumor necrosis factor (TNF) inhibitor, showed swelling of the salivary glands and retroperitoneal fibrosis, which was diagnosed as IgG4-related disease. Although some reports have shown the efficacy of TNF inhibitors for IgG4-related disease or retroperitoneal fibrosis, TNF inhibitors sometimes cause paradoxical reactions like psoriasis, and the mechanisms are considered to involve the upregulation of plasmacytoid dendritic cells and IFN-α, which is also common in patients with IgG4-related disease. This is a case report of IgG4-related retroperitoneal fibrosis with the possibility of a rare paradoxical reaction by a TNF inhibitor.

Importance of Awareness and Careful Follow-Up of Suspected IgG4-Related Periaortitis.

IgG4-related disease may cause large vessel vasculitis, which often affects males in their 60s. Here, we report a case of suspected IgG4-related periaortitis in a 76-year-old man with lower left-side chest pain and hypertension based on computed tomography findings of thickened lesions surrounding the abdominal aorta and mesenteric arteries after ruling out acute cardiovascular diseases. His serum IgG4 levels were high, but the C-reactive protein and D-dimer levels were within normal limits. Because IgG4-related periaortitis was suspected, the patient was carefully monitored for blood pressure control, inflammatory markers, and renal function. Steroid therapy was not initiated, however, due to the difficulties performing a biopsy targeting periaortitis to obtain a definitive diagnosis and possible severe complications. During follow-up observation, IgG4-related kidney disease was suspected based on a slight increase in the serum creatinine levels and a renal biopsy was considered. Just before performing the renal biopsy, we observed left renal hydronephrosis caused by spreading retroperitoneal fibrosis. Immediate ureteral stent implantation and initiation of steroid therapy successfully improved the renal function and decreased the serum IgG4 level, respectively. Although relatively rare, IgG4-related periaortitis/periarteritis and retroperitoneal fibrosis should be considered in the differential diagnosis of aortic diseases, even after ruling out serious major acute cardiovascular diseases. Cardiologists should also be aware of the possible progression and systemic spread of this disease.

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.

Multidisciplinary diagnosis and management of inflammatory aortic aneurysms.

BACKGROUND: Inflammatory abdominal aortic aneurysms (IAAAs) are a variant involving a distinct immunoinflammatory process, with nearly one half believed to be associated with IgG4-related disease (IgG4-RD). METHODS: MEDLINE and Google Scholar searches were conducted for English-language publications relevant to inflammatory aortic aneurysms from January 1970 onward. The search terms included inflammatory aortic aneurysms, aortitis, periaortitis, IgG4-related disease, and retroperitoneal fibrosis. Relevant studies were selected for review based on their relevance. RESULTS: Morphologically, IAAAs are characterized by a thickened aneurysm wall often displaying contrast enhancement and elevated metabolic activity on fluorine-18 fluorodeoxyglucose-positron emission tomography imaging. A strong association exists with perianeurysmal and retroperitoneal fibrosis. Although the rupture risk appears lower with IAAAs than with noninflammatory abdominal aortic aneurysms (AAAs), the currently recommended diameter threshold for operative management is the same. Open repair has been associated with increased morbidity compared with noninflammatory AAAs, and a retroperitoneal approach or minimal dissection transperitoneal approach has been recommended to avoid duodenal and retroperitoneal structural injuries. Endovascular aneurysm repair has been increasingly used, especially for patients unfit for open surgery. It is important to exclude an infectious etiology before the initiation of immunosuppressive therapy or operative repair. Multimodality imaging follow-up is critical to monitor disease activity and secondary involvement of retroperitoneal structures by the associated fibrotic process. Maintenance of immunosuppressive therapy will be needed postoperatively for most patients with active systemic disease, especially those with IgG4-RD and those with persistent symptoms. Additional interventions aimed at ureteral decompression could also be required, and lifelong follow-up is mandatory. CONCLUSIONS: Preoperative multimodality imaging is a diagnostic cornerstone for assessment of the disease extent and activity. IgG4-RD is an increasingly recognized category of IAAAs, with implications for tailoring adjunctive medical therapy. Open surgical repair remains the procedure of choice, although endovascular aneurysm repair is increasingly being offered. Maintenance immunosuppressive therapy can be offered according to the disease activity as assessed by follow-up imaging studies.

A unified serum IgG4 cut-off level for the diagnosis of IgG4-related disease using a wide array of kits.

OBJECTIVES: An immunoglobulin G4 (IgG4) level above 1350 mg/L is one of the comprehensive criteria for the diagnosis of IgG4-related disease (IgG4-RD). The purpose of this study was to evaluate the differences in IgG4 levels determined using reagents from two main manufacturers and their concordance with clinical diagnosis. METHODS: IgG4 levels were measured in 309 patients, including 146, 40, 42, 41, and 40 patients with untreated IgG4-RD, pancreatic cancer, primary Sjogren syndrome, systemic lupus erythematosus, and idiopathic retroperitoneal fibrosis, respectively, and 141 healthy controls. The results obtained using the Binding Site and Siemens reagents were compared in patients with IgG4-RD. RESULTS: The serum IgG4 level measured using the Siemens reagent was almost two times that measured using the Binding Site reagent. The rate of IgG4-negative patients, which was 19.9% based on measurement using the Binding Site reagent, was only 4.8% based on measurement using the Siemens reagent (p < .001). CONCLUSIONS: There were significant differences in serum IgG4 levels based on commonly used reagents from different manufacturers. The IgG4 cut-off level of 1350 mg/L was not suitable for all detection reagents. Clinicians and patients should be cognizant of these differences associated with the specific detection reagents when evaluating the test results.

IgG4-related disease diagnosed in a paratesticular pseudotumor simulating malignancy, in a patient with retroperitoneal fibrosis.

IgG4 related disease is a term used to describe a fibroinflammatory condition characterized by storiform fibrosis, inflammation with a dense lymphoplasmocytic infiltrate rich in plasma cells expressing IgG4, and often, if not always, raised serum levels of IgG4. We report a case of a patient with a past history of retroperitoneal fibrosis presenting with a swollen left testicle, who underwent an orchidectomy due to suspicion of malignancy. The surgical specimen revealed a paratesticular pseudotumor with histopathological and immunohistochemical characteristics of IgG4 related disease. To the best of our knowledge, just nine such cases have previously been reported, of which only three were manifestations of systemic disease, as in the present case. Whilst it is important to recognize the clinical and radiological features of this entity, histopathology is often essential in order to confirm the diagnosis.

Retroperitoneal fibrosis - diagnosis and treatment.

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. Pain is frequently referred to the hip, to the groin and to the lateral regions of the leg, often with nocturnal exacerbations and not responding to position changes. The disease is commonly associated with signs of systemic inflammatory response (malaise, fever, and anorexia and weight loss). Glucocorticoids are considered the cornerstone of the therapy. The use of other immunosuppressive agents, including cyclophosphamide, azathioprine, methotrexate, mycophenolate mofetil and biological agents such as rituximab, tocilizumab and infliximab have been reported as a valuable option mostly in case reports, cases series and small studies. These agents allowed to reduce cumulative dose of glucocorticoids and their adverse effects. Combined therapy is preferable for all patients who suffer from significant glucocorticoid- related toxicity or in cases where glucocorticoids alone are insufficient to treat the condition.