Immunoglobulin G4-related autoimmune pancreatitis and sialadenitis: A case report

Immunoglobulin G4(Ig G4)-related disease is a rare systemic diseases. A 67-year-old male presented at our institution with mild upper abdominal pain and jaundice for 20 d. Laboratory results revealed high levels of Ig G4(15.4 g/L,range: 0.08-1.4 g/L). Computed tomography(CT) showed significant enlargement of the entire pancreas and a capsule-like low-density rim surrounding the whole pancreas. Positron emission tomography/CT revealed increased uneven metabolism of the entire pancreas. Both magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography showed stenosis of the distal common bile duct and proximal main pancreatic duct,and dilation of the proximal common bile duct and extra- and intra-hepatic bile ducts. He was diagnosed with Ig G4-related autoimmune pancreatitis. The patient was treated with prednisone for 14 mo. The patient responded well to prednisone but upon cessation of the corticosteroid developed enlargement of the submandibular gland. The patient's serum Ig G4 was elevated at 23.9 g/L. It is important to maintain treatment,so the patient was again treated with prednisone and had a good response. Follow-up of Ig G4-related disease is thus necessary.

Clinical characteristics and outcome of autoimmune pancreatitis based on serum immunoglobulin G4 level:A single-center,retrospective cohort study

BACKGROUND Autoimmune pancreatitis(AIP)has been linked with elevated immunoglobulin(Ig)G4 levels.The characteristics and outcomes of AIP based on serum markers have not been fully evaluated.AIM To compare clinical features,treatment efficacy,and outcome of AIP based on serum IgG4 levels and analyze predictors of relapse.METHODS A total of 213 patients with AIP were consecutively reviewed in our hospital from 2006 to 2021.According to the serum IgG4 level,all patients were divided into two groups,the abnormal group(n=148)with a high level of IgG4[>2×upper limit of normal(ULN)]and the normal group(n=65).The t-test or Mann-Whitney U test was used to compare continuous variables.Categorical parameters were compared by theχ^(2) test or Fisher’s exact test.Kaplan-Meier curves Zhou GZ et al.Clinical characteristics and outcome of AIP WJG https://www.wjgnet.com 5126 September 21,2023 Volume 29 Issue 35 and log-rank tests were established to assess the cumulative relapse rates.Univariate and multivariate analyses were used to investigate potential risk factors of AIP relapse.RESULTS Compared with the normal group,the abnormal group had a higher average male age(60.3±10.4 vs 56.5±12.9 years,P=0.047);higher level of serum total protein(72.5±7.9 g/L vs 67.2±7.5 g/L,P<0.001),IgG4(1420.5±1110.9 mg/dL vs 252.7±106.6 mg/dL,P<0.001),and IgE(635.6±958.1 IU/mL vs 231.7±352.5 IU/mL,P=0.002);and a lower level of serum complement C3(100.6±36.2 mg/dL vs 119.0±45.7 mg/dL,P=0.050).In addition,a lower number of cases with abnormal pancreatic duct and pancreatic atrophy(23.6%vs 37.9%,P=0.045;1.6%vs 8.6%,P=0.020,respectively)and a higher rate of relapse(17.6%vs 6.2%,P=0.030)were seen in the abnormal group.Multivariate analyses revealed that serum IgG4[(>2×ULN),hazard ratio(HR):3.583;95%confidence interval(CI):1.218–10.545;P=0.020]and IgA(>1×ULN;HR:5.908;95%CI:1.199–29.120;P=0.029)and age>55 years(HR:2.383;95%CI:1.056–5.378;P=0.036)were independent risk factors of relapse.CONCLUSION AIP patients with high IgG4 levels have clinical features including a more active immune system and higher relapse rate.Several factors,such as IgG4 and IgA,are associated with relapse.

Understanding autoimmune pancreatitis: Clinical features, management challenges, and association with malignancies

In this editorial we comment on the article by Jaber et al.Autoimmune pancreatitis(AIP)represents a distinct form of pancreatitis,categorized into AIP-1 and AIP-2,characterized by obstructive jaundice,lymphoplasmacytic infiltrate,and fibrosis.AIP-1,associated with elevated immunoglobulin G4(IgG4)levels,exhibits higher relapse rates,affecting older males,while AIP-2 is less common and linked to inflammatory bowel disease.AIP is considered a manifestation of IgG4-related systemic disease,sharing characteristic histological findings.Steroids are the primary treatment,with emerging biomarkers like interferon alpha and inter-leukin-33.AIP poses an increased risk of various malignancies,and the assoc-iation with pancreatic cancer is debated.Surgery is reserved for severe cases,necessitating careful evaluation due to diagnostic challenges.AIP patients may have concurrent PanINs but display favorable long-term outcomes compared to pancreatic cancer patients.Thorough diagnostic assessment,including biopsy and steroid response,is crucial for informed surgical decisions in AIP.

Clinical characteristics and outcomes of autoimmune pancreatitis based on serum immunoglobulin G4 levels:A single-center,retrospective cohort study

Autoimmune pancreatitis(AIP)is a complex,poorly understood disease gaining increasing attention."Clinical Characteristics and Outcome of AIP Based on Serum IgG4 levels,"investigated AIP with a focus on serum immunoglobulin(Ig)G4 levels.The 213 patients with AIP were classified according to serum IgG4 levels:Abnormal(elevated)and normal.Patients with higher IgG4 levels exhibited a more active immune system and increased relapse rates.Beyond IgG4,the IgA levels and age independently contributed to relapse risk,guiding risk assessment and tailored treatments for better outcomes.However,limitations persist,such as no IgA correlation with IgG4 levels,absent data on autoantibodypositive AIP cases critical for Asian diagnostic criteria,and unexplored relapse rates in high serum IgG AIP by subtype.Genetic factors and family histories were not addressed.As the understanding and referral of seronegative AIPs increase,there's a growing need for commercially available,highly sensitive,and specific autoantibodies to aid in diagnosing individuals with low or absent serum IgG4 levels.

Unmet needs in biomarkers for autoimmune pancreatitis diagnosis

Autoimmune pancreatitis(AIP)is a rare chronic autoimmune disorder.The diagnosis of AIP mainly depends on histopathology,imaging and response to treatment.Serum immunoglobulin 4(IgG4)is used only as collateral evidence in diagnostic criteria for AIP because of its moderate sensitivity.Serum IgG4 levels are normal in 15%-37%of type 1 AIP and most of type 2 AIP patients.In these patients,the indeterminate imaging and histopathology may lead to the difficulty in definitive diagnosis of AIP.Therefore,discovery of new biomarkers is impor-tant for AIP diagnosis.Here,we provide some views on the progression and challenges in identifying novel serological biomarkers in AIP diagnosis.

Type one autoimmune pancreatitis based on clinical diagnosis: A case report

BACKGROUND Autoimmune pancreatitis(AIP)is a rare form of autoimmune-mediated pancrea-titis,which is easily misdiagnosed as pancreatic cancer and thus treated surgi-cally.We studied the diagnosis and treatment of a patient with type 1 AIP recent-ly admitted to our hospital,and reviewed the literature to provide a reference for clinical diagnosis of AIP.CASE SUMMARY The chief complaint was yellowing of the body,eyes and urine for 21 d.The pa-tient's clinical presentation was obstructive jaundice and imaging suggested pan-creatic swelling.It was difficult to distinguish between inflammation and tumor.Serum immunoglobulin G4(IgG4)was markedly elevated.IgG4 is an important serological marker for type 1 AIP.The patient was diagnosed with AIP,IgG4-related cholangitis,acute cholecystitis and hepatic impairment.After applying hormonal therapy,the patient's symptoms improved significantly.At the same time,imaging suggested that pancreatic swelling subsided,and liver function and other biochemical indicators decreased.The treatment was effective.CONCLUSION In patients with pancreatic swelling,the possibility of AIP should be considered.

Biomarkers in autoimmune pancreatitis and immunoglobulin G4-related disease

Solitary organ autoimmune disorders,formerly known as autoimmune pancreatitis(AIP),autoimmune sialadenitis,and autoimmune sclerosing cholangitis,are now considered organ-specific manifestations of systemic immunoglobulin G4-related disease(IgG4-RD).AIP and IgG4-RD are characterized by elevated serum concentration of IgG4 antibody(Ab),accumulation of IgG4-expressing plasmacytes in the affected organs,and involvement of multiple organs.It is well established that enhanced IgG4 Ab responses are a hallmark of AIP and IgG4-RD for diagnosis and monitoring disease activity.However,a significant fraction of patients with AIP and IgG4-RD who develop chronic fibroinflammatory responses have normal serum concentrations of this IgG subtype.In addition,disease flare-up is sometimes seen even in the presence of normalized serum concentrations of IgG4 Ab after successful induction of remission by prednisolone.Therefore,it is necessary to identify new biomarkers based on the understanding of the pathophysiology of AIP and IgG4-RD.Recently,we found that activation of plasmacytoid dendritic cells producing both interferon-α(IFN-α)and interleukin-33(IL-33)mediate murine AIP and human IgG4-RD.More importantly,we provided evidence that serum concentrations of IFN-αand IL-33 could be useful biomarkers for the diagnosis and monitoring of AIP and IgG4-RD activity after induction of remission in these autoimmune disorders.In this Frontier article,we have summarized and discussed biomarkers of AIP and IgG4-RD,including Igs,autoAbs,and cytokines to provide useful information not only for clinicians but also for researchers.

Autoimmune pancreatitis in the context of IgG4-related disease:Review of imaging findings

Current understanding of autoimmune pancreatitis (AIP) recognizes a histopathological subtype of the disease to fall within the spectrum of IgG4-related disease. Along with clinical, laboratory, and histopathological data, imaging plays an important role in the diagnosis and management of AIP, and more broadly, within the spectrum of IgG4-related disease. In addition to the defined role of imaging in consensus diagnostic protocols, an array of imaging modalities can provide complementary data to address specific clinical concerns. These include contrast-enhanced computed tomography (CT) and magnetic resonance (MR) imaging for pancreatic parenchymal lesion localization and characterization, endoscopic retrograde and magnetic resonance cholangiopancreatography (ERCP and MRCP) to assess for duct involvement, and more recently, positron emission tomography (PET) imaging to assess for extra-pancreatic sites of involvement. While the imaging appearance of AIP varies widely, certain imaging features are more likely to represent AIP than alternate diagnoses, such as pancreatic cancer. While nonspecific, imaging findings which favor a diagnosis of AIP rather than pancreatic cancer include: delayed enhancement of affected pancreas, mild dilatation of the main pancreatic duct over a long segment, the &#x0201c;capsule&#x0201d; and &#x0201c;penetrating duct&#x0201d; signs, and responsiveness to corticosteroid therapy. Systemic, extra-pancreatic sites of involvement are also often seen in AIP and IgG4-related disease, and typically respond to corticosteroid therapy. Imaging by CT, MR, and PET also play a role in the diagnosis and monitoring after treatment of involved sites.

Autoimmune pancreatitis:Cornerstones and future perspectives

Autoimmune pancreatitis(AIP)is an autoimmune subtype of chronic pancreatitis resulting from the aberrant immune response against the pancreas,leading to inflammation and fibrosis.Although AIP is rare,its incidence is increasing and is often misdiagnosed as other pancreatic diseases.AIP is commonly classified into two types.Type 1 AIP(AIP-1)is typically associated with elevated serum immunoglobulin G4(IgG4)levels and systemic manifestations,while type 2 AIP is typically a more localized form of the disease,and may coexist with other autoimmune disorders,especially inflammatory bowel diseases.Additionally,there is emerging recognition of a third type(type 3 AIP),which refers to immunotherapy-triggered AIP,although this classification is still gaining acceptance in medical literature.The clinical manifestations of AIP mainly include painless jaundice and weight loss.Elevated serum IgG4 levels are particularly characteristic of AIP-1.Diagnosis relies on a combination of clinical,laboratory,radiological,and histological findings,given the similarity of AIP symptoms to other pancreatic disorders.The mainstay of treatment for AIP is steroid therapy,which is effective in most cases.Severe cases might require additional imm-unosuppressive agents.This review aims to summarize the current knowledge of AIP,encompassing its epidemiology,etiology,clinical presentation,diagnosis,and treatment options.We also address the challenges and controversies in diagnosing and treating AIP,such as distinguishing it from pancreatic cancer and managing long-term treatment,highlighting the need for increased awareness and knowledge of this complex disease.

IgG4-related Autoimmune Pancreatitis Mimicking Acute Pancreatitis:A Case Report

IGG4-RELATED autoimmune pancreatitis (AIP) is themost common type of IgG4-related diseases. Theobservation of a diffused and localized enlargementof the pancreas and strictures in the main pancreaticduct on radiological imaging is essential fordiagnosing AIP. The clinical features of AIP which presentas a localized pancreatic mass greatly mimic pancreaticcancer. Cases with AIP mimicking pancreatic cancer arereported numerously. However, cases of IgG4-related AIPmanifesting acute pancreatitis symptoms and extensiveperipancreatic effusion are rarely observed. Meanwhile,acute pancreatitis is a common disease. If misdiagnosed asacute pancreatitis, IgG4-related AIP may progressseriously. Here, we report a rare case of IgG4-related AIPsuspected of acute pancreatitis because of epigastric painand extensive peripancreatic effusion on computed tomography(CT) images.

IgG4-related autoimmune pancreatitis overlapping with Mikulicz's disease and lymphadenitis:A case report

Autoimmune pancreatitis(AIP)is a form of chronic pancreatitis that is categorized as type 1 or type 2according to the clinical profile.Type 1 AIP,which predominantly presents in a few Asian countries,is a hyper-IgG4-related disease.We report a case of IgG4-related AIP overlapping with Mikulicz’s disease and lymphadenitis,which is rare and seldom reported in literature.A 63-year male from Northeast China was admitted for abdominal distension lasting for one year.He presented symmetric swelling of the parotid and submandibular glands with slight dysfunction of salivary secretion for 6 mo.He had a 2-year history of bilateral submandibular lymphadenopathy without pain.He underwent surgical excision of the right submandibular lymph node one year prior to admission.He denied any history of alcohol,tobacco,or illicit drug use.Serological examination revealed high fasting blood sugar level(8.8 mmol/L)and high level of IgG4(15.2 g/L).Anti-SSA or anti-SSB were negative.Computed tomography of the abdomen showed a diffusely enlarged pancreas with loss of lobulation.Immunohistochemical stain for IgG4 demonstrated diffuse infiltration of IgG4-positive plasma cells in labial salivary gland and lymph node biopsy specimens.The patient received a dose of 30 mg/d of prednisone for three weeks.At this three-week follow-up,the patient reported no discomfort and his swollen salivary glands,neck lymph node and pancreas had returned to normal size.The patient received a maintenance dose of 10mg/d of prednisone for 6 mo,after which his illness had not recurred.

IgG4-related sclerosing cholangitis associated with essential thrombocythemia:A case report

BACKGROUND The complexity of immunoglobulin G4(IgG4)-related diseases and their potential connection to hematologic malignancies remains unclear.This article provided a review of the diagnosis and treatment of a patient with IgG4-related sclerosing cholangitis(SC)and essential thrombocythemia(ET),along with an analysis of relevant literature to enhance comprehension of this disease.CASE SUMMARY A 56-year-old male was admitted to two hospitals with deteriorating jaundice and pruritus prior to hospitalization.Beyond our expectations,the patient was first diagnosed with IgG4-SC and ET with the Janus kinase 2 V617F mutation.Interestingly,the administration of acetate prednisone significantly resulted in improvements in both IgG4-SC and ET.Clinicians need to pay attention to immune disorders and inflammation as they contribute to the development of various disease phenotypes.CONCLUSION When IgG4-SC is suspected without histopathological evidence,diagnostic therapy and long-term regular follow-up can lead to positive treatment outcomes.Clinicians should be mindful of the potential presence of concurrent hematologic diseases in patients with immune disorders.

Journey to diagnosis:An unfinished exploration of IgG4-related sclerosing cholangitis

IgG4-related sclerosing cholangitis(IgG4-SC)is an inflammatory disease that leads to bile duct stricture,characterized by the infiltration of IgG4-positive plasma cells into the bile duct wall,thickening of the bile duct wall,and narrowing of the lumen.The differential diagnosis of IgG4-SC mainly includes primary sclerosing cholangitis,cholangiocarcinoma,and pancreatic cancer.IgG4-SC is often associated with autoimmune pancreatitis and can be accurately diagnosed based on clinical diagnostic criteria.However,isolated IgG4-SC is difficult to distinguish from biliary tumors.Given the significant differences in biological behavior,treatment,and prognosis between these diseases,accurately identifying isolated IgG4-SC has very important clinical significance.

Clinical and pathological differences between serum immunoglobulin G4-positive and -negative type 1 autoimmune pancreatitis

AIM: To identify clinical and pathological differences between serum immunoglobulin G4 (IgG4)-positive (SIP) and IgG4-negative (SIN) type 1 autoimmune pancreatitis (AIP) in South Korea. METHODS: AIP was diagnosed by the international consensus diagnostic criteria. The medical records and pathology were retrospectively reviewed and IgG4-positive cells were counted in a high power field (HPF). Type I AIP was defined as a high serum level of IgG4or histological finding. SIN type 1 AIP was defined as a histological evidence of type 1 AIP and a normal serum IgG4 level. The clinical and pathological findings were compared between the two groups. The analysis was performed using Student's t test, Fischer's exact test and Mann-Whitney's U test. A P value of < 0.05 was considered statistically significant. As repeated com- parison was made, P values of less than 5% (P < 0.05) were considered significant. RESULTS: Twenty five patients with definite type 1 AIP (19 histologically and six serologically diagnosed cases) were enrolled. The mean tissue IgG4 concentrations were significantly higher in SIP than SIN group (40 cells per HPF vs 18 cells per HPF, P = 0.02). Among eight SIN patients, the tissue IgG4 concentrations were less than 15 cells per HPF in most of cases, except one. The sensitivity of serum IgG4 was 68% (17 SIP and eight SIN AIP). Other organ involvement was more frequent- ly associated with SIP than SIN AIP (59% vs 26%, P = 0.016). However, the relapse rate and diffuse swelling of the pancreas were not associated with serum IgG4 level. The concentrations of IgG4-positive cells per HPF were higher in SIP than SIN AIP (40 vs 18, P = 0.02). CONCLUSION: The sensitivity of serum IgG4 was 68% in type 1 AIP. High serum IgG4 level was associated with other organ involvement and tissue IgG4 concentration but did not affect the relapse rate in type 1 AIP.

Immunoglobulin G4 associated autoimmune cholangitis and pancreatitis following the administration of nivolumab:A case report

BACKGROUND Immune checkpoint inhibitors have significantly improved survivals for an increasing range of malignancies but at the cost of several immune-related adverse events,the management of which can be challenging due to its mimicry of other autoimmune related disorders such as immunoglobulin G4(IgG4)related disease when the pancreaticobiliary system is affected.Nivolumab,an IgG4 monoclonal antibody,has been associated with cholangitis and pancreatitis,however its association with IgG4 related disease has not been reported to date.CASE SUMMARY We present a case of immune-related pancreatitis and cholangiopathy in a patient who completed treatment with nivolumab for anal squamous cell carcinoma.Patients IgG4 levels was normal on presentation.She responded to steroids but due to concerns for malignant biliary stricture,she opted for surgery,the pathology of which suggested IgG4 related disease.CONCLUSION We hypothesize this case of IgG4 related cholangitis and pancreatitis was likely triggered by nivolumab.

Infrequent organ involvement in immunoglobulin G4-related prostate disease: A case report

BACKGROUND Immunoglobulin G4-related prostate disease(IgG4-RPD)characterized by a high count of IgG4-positive plasma cells has distinctive serological and radiological findings.Here we report a case of a patient who was successfully treated for IgG4-RPD,which manifested as frequent micturition,dysuric,and systemic lymphadenopathy.CASE SUMMARY The patient was a 33-year-old man who was referred to our hospital because of urinary tract symptoms that had persisted for 4 years.A physical examination revealed systemic lymphadenopathy and blood tests showed hyperglobulinemia with an IgG level of 18.90 g/L and an IgG4 level of 18.40 g/L.Computed tomography(CT)revealed bilateral lacrimal gland,right parotid gland and prostatic enlargement.Based on these findings,IgG4-RD was suspected,and further pathological examination and follow-up results showed expected results.Finally,the patient was diagnosed with IgG4-RPD based on clinical symptoms,pathological examination,therapeutic effects,and follow-up results.He received 50 mg oral prednisolone(the dose was gradually reduced and a low dose was used for long-term maintenance)in combination with cyclophosphamide 1.0 g via an intravenous drip for 6 mo.One year after the treatment was initiated,he was free of urinary or other complaints and his serum IgG4 level normalized.CONCLUSION In IgG4-RPD with severe urinary tract symptoms,radiological findings should be carefully examined.IgG4-RPD prognosis is good because the disease responds well to glucocorticoids.Furthermore,it is urgent for clinicians and pathologists to improve their understanding of IgG4-RPD.

Usefulness of ultrasonography to assess the response to steroidal therapy for the rare case of type 2b immunoglobulin G4-related sclerosing cholangitis without pancreatitis:A case report

BACKGROUND A type 2b immunoglobulin G4(IgG4)-related sclerosing cholangitis(SC)without autoimmune pancreatitis is a rare condition with IgG4-SC.While the variety of the imaging modalities have tested its usefulness in diagnosing the IgG4-SC,however,the usage of ultrasonography for the assessment of the response to steroidal therapy on the changes of bile duct wall thickness have not been reported in the condition.Therefore,the information of our recent case and reported cases have been summarized.CASE SUMMARY We report the case of an 82-year-old Japanese man diagnosed with isolated IgG4-related SC based on the increase of serum IgG4,narrowing of the bile duct,its wall thickness,no complication of autoimmune pancreatitis,and IgG4 positive inflammatory cell infiltration to the wall with the fibrotic changes.The cholangiogram revealed type 2b according to the classification.Corticosteroid treatment showed a favorable effect,with the smooth decrease in serum IgG4 and the improvement of the bile duct wall thickness.CONCLUSION As isolated type 2b,IgG4-SC is rare,the images,histological findings,and clinical course of our case will be helpful for physicians to diagnose and treat the new cases appropriately.

Immunoglobulin G4 associated autoimmune cholangitis and pancreatitis and nivolumab

This letter to editor discussing on the publication on immunoglobulin G4 associated autoimmune cholangitis and pancreatitis following the administration of nivolumab.Concerns on confounding factors are raised and discussed.

First case of IgG4-related sclerosing cholangitis associated with autoimmune hemolytic anemia

To our knowledge,patients with immunoglobulin G4-related sclerosing cholangitis(IgG4-SC)associated with autoimmune hemolytic anemia(AIHA)have not been reported previously.Many patients with IgG4-SC have autoimmune pancreatitis(AIP)and respond to steroid treatment.However,isolated cases of IgG4-SC are difficult to diagnose.We describe our experience with a patient who had IgG4-SC without AIP in whom the presence of AIHA led to diagnosis.The patient was a73-year-old man who was being treated for dementia.Liver dysfunction was diagnosed on blood tests at another hospital.Imaging studies suggested the presence of carcinoma of the hepatic hilus and primary sclerosing cholangitis,but a rapidly progressing anemia developed simultaneously.After the diagnosis of AIHA,steroid treatment was begun,and the biliary stricture improved.IgG4-SC without AIP was thus diagnosed.

Retroperitoneal fibrosis associated with immunoglobulin G4-related disease

Retroperitoneal fibrosis is a rare disease characterized by the development of inflammation and fibrosis in the soft tissues of the retroperitoneum and other abdominal organs.Retroperitoneal fibrosis can be of 2 types:idiopathic and secondary.The recently advocated concept and diagnostic criteria of immunoglobulin G4(IgG4)-related disease,derived from research on autoimmune pancreatitis(AIP),has led to widespread recognition of retroperitoneal fibrosis as a condition caused by IgG4-related disease.We now know that previously diagnosed idiopathic retroperitoneal fibrosis includes IgG4-related disease;however,the actual prevalence is unclear.Conversely,some reports on AIP suggest that retroperitoneal fibrosis is concurrently found in about 10% of IgG4-related disease.Because retroperitoneal fibrosis has no specific symptoms,diagnosis is primarily based on diagnostic imaging(computed tomography and magnetic resonance imaging),which is also useful in evaluating the effect of therapy.Idiopathic retroperitoneal fibrosis can occur at different times with other lesions of IgG4-related disease including AIP.Thus,the IgG4 assay is recommended to diagnose idiopathic retroperitoneal fibrosis.High serum IgG4 levels should be treated and monitored as a symptom of IgG4-related disease.The first line of treatment for retroperitoneal fibrosis is steroid therapy regardless of its cause.For patients with concurrent AIP,i.e.,IgG4-related retroperitoneal fibrosis,the starting dose of steroid is usually 30-40 mg/d.The response to steroid therapy is generally favorable.In most cases,the pancreatic lesion and retroperitoneal fibrosis improve after the initial treatment.However,the epidemiology,treatment for recurring retroperitoneal fibrosis,and long-term prognosis are still largely unknown.Further analysis of such cases and research are necessary.