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Mizuno T, Endo Y, Suzuki A, Suzuki M. IgG4-Related Membranous Nephropathy After COVID-19 Vaccination: A Case Report. Cureus 2024; 16:e56028. [PMID: 38606210 PMCID: PMC11008612 DOI: 10.7759/cureus.56028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2024] [Indexed: 04/13/2024] Open
Abstract
Although immunoglobulin G4 (IgG4)-related kidney diseases are typically characterized by tubulointerstitial nephritis with abundant infiltration of IgG4-positive plasma cells and fibrosis, there have been relatively rare cases of IgG4-related glomerulonephritis. Several cases of IgG4-related disease (IgG4-RD) following coronavirus disease 2019 (COVID-19) mRNA vaccination have been reported. However, there are no reports of IgG4-related glomerulonephritis following COVID-19 vaccination. Herein, we present a case of IgG4-related membranous nephropathy (MN) occurring after COVID-19 vaccination. A 69-year-old Japanese male presented to our hospital with edema that started the day after his second COVID-19 vaccination. The patient exhibited nephrotic syndrome and was diagnosed with MN based on the results of a kidney biopsy. Although serum IgG4 levels were elevated to 946 mg/dL, no evidence of organ involvement suggestive of IgG4-RD was observed. Treatment with prednisolone and cyclosporine resulted in complete remission, and immunosuppressive agents were tapered. However, one month after discontinuing the immunosuppressive agents, the patient was readmitted with swelling around the submandibular glands and exertional dyspnea. Serum IgG4 level was markedly elevated at 2,320 mg/dL, and computed tomography revealed submandibular gland swelling and thickening of the interlobular septum and bronchovascular bundles in both lungs. The patient was diagnosed with IgG4-RD based on elevated serum IgG4 levels and infiltration of IgG4-positive plasma cells in the submandibular gland biopsy. Upon resuming treatment with prednisolone, the symptoms attributed to IgG4-RD improved within a few days. In cases of nephrotic syndrome following COVID-19 vaccination, it may be advisable to conduct detailed examinations to assess the possibility of the development of IgG4-RDs.
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Affiliation(s)
- Tomohito Mizuno
- Department of Internal Medicine, Division of Nephrology, Tokyo Yamate Medical Center, Tokyo, JPN
| | - Yoko Endo
- Department of Internal Medicine, Division of Nephrology, Tokyo Yamate Medical Center, Tokyo, JPN
- Department of Pathology, Tokyo Yamate Medical Center, Tokyo, JPN
| | - Atsushi Suzuki
- Department of Internal Medicine, Division of Nephrology, Tokyo Yamate Medical Center, Tokyo, JPN
| | - Masashi Suzuki
- Department of Internal Medicine, Division of Nephrology, Tokyo Yamate Medical Center, Tokyo, JPN
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Plens GCM, Bridi GDP, Nascimento ECTD, Chate RC, Baldi BG, Arimura FE, Kairalla RA. Nephrobronchial fistula: a diagnostic challenge in a patient with IgG4-related disease. J Bras Pneumol 2024; 49:e20230317. [PMID: 38198347 PMCID: PMC10760433 DOI: 10.36416/1806-3756/e20230317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024] Open
Affiliation(s)
- Glauco Cabral Marinho Plens
- . Divisão de Pneumologia, Instituto do Coração - InCor - Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | - Guilherme das Posses Bridi
- . Divisão de Pneumologia, Instituto do Coração - InCor - Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | | | - Rodrigo Caruso Chate
- . Divisão de Radiologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | - Bruno Guedes Baldi
- . Divisão de Pneumologia, Instituto do Coração - InCor - Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | - Fábio Eiji Arimura
- . Divisão de Pneumologia, Instituto do Coração - InCor - Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | - Ronaldo Adib Kairalla
- . Divisão de Pneumologia, Instituto do Coração - InCor - Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
- . Divisão de Radiologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
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Guo L, Yang Z, Cheng Y, Wang X, Ren X, Wang M, Yan P, Shen J, Sun K, Wang H, Wu J, Chen J, Wang R. Clinical phenotypes and prognosis of IgG4-related diseases accompanied by deteriorated kidney function: a retrospective study. Clin Rheumatol 2024; 43:315-324. [PMID: 37642763 DOI: 10.1007/s10067-023-06748-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 08/07/2023] [Accepted: 08/18/2023] [Indexed: 08/31/2023]
Abstract
INTRODUCTION IgG4-related disease (IgG4-RD) is a multiorgan autoimmune disorder that causes irreversible injury. Deteriorated kidney functions are common but easily ignored complications associated with IgG4-RD. Yet the clinical manifestations and prognosis of this specific entity have not been fully illustrated. METHOD Three hundred fifty patients with IgG4-RD were retrospectively enrolled and divided into 119 IgG4-RD with chronic kidney disease (IgG4-RD CKD+) and 231 IgG4-RD without CKD (IgG4-RD CKD-). Demographic clinical and laboratory characteristics and survival of two cohorts were compared using restricted cubic splines, logistic and Cox regression, and Kaplan-Meier analysis. A nomogram was generated for calculating the probability of CKD in IgG4-RD. RESULTS The spectrum of organ involvement was different between IgG4-RD CKD+ and CKD- cohorts (p<0.001). Lung (26.89%) and retroperitoneum (18.49%) involvement were more common in the IgG4-RD CKD+ cohort. Increased serum potassium and phosphorus, reduced calcium levels, and hypocomplementemia (all p<0.05) were observed in IgG4-RD CKD+. Restricted cubic splines revealed a U-shaped plot regarding associations between serum potassium and CKD. Kaplan-Meier analysis demonstrated significantly lower long-term survival rates in IgG4-RD patients with kidney function at CKD stages 4-5. Cox regression revealed declined kidney functions (G4 HR 6.537 (95% CI: 1.134-37.675)) associated with increased all-cause mortality in IgG4-RD patients. A nomogram was constructed to predict CKD in IgG4-RD promptly with a discrimination (C-index) of 0.846. CONCLUSIONS CKD in IgG4-RD was associated with poor outcomes and electrolyte disturbances. Patients with IgG4-RD should be aware of possible deterioration in kidney function. The nomogram proposed would help to identify the subtle possibility of CKD in IgG4-RD. Key points • IgG4-related diseases with deteriorated kidney function have specific clinical and laboratory characteristics. • It is crucial to recognize and address the negative impact of deteriorating kidney function in IgG4-related diseases to prevent further harm. • The nomogram proposed would help to identify subtle kidney involvement by evaluating the possibility of CKD in IgG4-related diseases.
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Affiliation(s)
- Luying Guo
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China
- National Key Clinical Department of Kidney Diseases, Hangzhou, China
- Institute of Nephrology, Zhejiang University, Hangzhou, China
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China
| | - Zhenzhen Yang
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Department of Nephrology, Huzhou Central Hospital, Huzhou, Zhejiang Province, China
| | - Yamei Cheng
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China
- National Key Clinical Department of Kidney Diseases, Hangzhou, China
- Institute of Nephrology, Zhejiang University, Hangzhou, China
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China
| | - Xingxia Wang
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Department of Nephrology, 903rd Hospital of PLA, Hangzhou, China
| | - Xue Ren
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Department of Nephrology, Huzhou Central Hospital, Huzhou, Zhejiang Province, China
| | - Meifang Wang
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China
- National Key Clinical Department of Kidney Diseases, Hangzhou, China
- Institute of Nephrology, Zhejiang University, Hangzhou, China
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China
| | - Pengpeng Yan
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China
- National Key Clinical Department of Kidney Diseases, Hangzhou, China
- Institute of Nephrology, Zhejiang University, Hangzhou, China
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China
| | - Jia Shen
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China
- National Key Clinical Department of Kidney Diseases, Hangzhou, China
- Institute of Nephrology, Zhejiang University, Hangzhou, China
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China
| | - Ke Sun
- Department of Pathology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Huiping Wang
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China
- National Key Clinical Department of Kidney Diseases, Hangzhou, China
- Institute of Nephrology, Zhejiang University, Hangzhou, China
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China
| | - Jianyong Wu
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China
- National Key Clinical Department of Kidney Diseases, Hangzhou, China
- Institute of Nephrology, Zhejiang University, Hangzhou, China
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China
| | - Jianghua Chen
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China.
- National Key Clinical Department of Kidney Diseases, Hangzhou, China.
- Institute of Nephrology, Zhejiang University, Hangzhou, China.
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China.
| | - Rending Wang
- Kidney Disease Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
- Key Laboratory of Kidney Disease Prevention and Control Technology, Hangzhou, Zhejiang Province, China.
- National Key Clinical Department of Kidney Diseases, Hangzhou, China.
- Institute of Nephrology, Zhejiang University, Hangzhou, China.
- Zhejiang Clinical Research Center of Kidney and Urinary System Disease, Hangzhou, China.
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Mete F, Mengeneci T, Albayrak E, Ayar Y, Nalbant M, Ozudeniz Mutlucan I, Fusun Baba Z. A rare case: IgG4-related chronic inflammatory disease with kidney involvement. Clin Case Rep 2024; 12:e8164. [PMID: 38161639 PMCID: PMC10753643 DOI: 10.1002/ccr3.8164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/05/2023] [Accepted: 10/10/2023] [Indexed: 01/03/2024] Open
Abstract
IgG4-related disease is an inflammatory, multisystemic disease that affects the immune system. The disease progresses to fibrosis due to inflammation. Retroperitoneal fibrosis is a serious complication. Pancreas, biliary tract, glands, thyroid, lymph nodes, etc. may be involved. Prognosis is usually subacute, and seen in middle age and advanced men. It is characterized histopathologically by IgG4 positive plasma cells, lymphoplasmocytic cell infiltration, and storiform fibrosis. In our case, we evaluated a patient who referred to our clinic from an external center with the complaints of generalized pain, itching, tearing and redness in eyes, involvement of bilateral large joints, and impaired renal function. Diagnosis, treatment and management of the disease are important. Response to glucocorticoid therapy is good.
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Affiliation(s)
- Fatos Mete
- Department of Internal MedicineBursa City HospitalBursaTurkey
| | - Tuba Mengeneci
- Department of Internal MedicineBursa City HospitalBursaTurkey
| | - Emre Albayrak
- Department of Internal MedicineBursa City HospitalBursaTurkey
| | - Yavuz Ayar
- Division of Nephrology, Department of Internal MedicineBursa City HospitalBursaTurkey
| | - Melike Nalbant
- Department of Medical PathologyBursa City HospitalBursaTurkey
| | | | - Zeliha Fusun Baba
- Department of Medical PathologyAcıbadem International HospitalIstanbulTurkey
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He PH, Liu LC, Zhou XF, Xu JJ, Hong WH, Wang LC, Liu SJ, Zeng JH. IgG4-related kidney disease complicated with retroperitoneal fibrosis: A case report. World J Clin Cases 2023; 11:1656-1665. [PMID: 36926395 PMCID: PMC10011980 DOI: 10.12998/wjcc.v11.i7.1656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/11/2023] [Accepted: 02/15/2023] [Indexed: 03/02/2023] Open
Abstract
BACKGROUND IgG4-related disease (IgG4-RD) is a chronic fibrotic disease mediated by immunity recognized by clinicians in recent years. When the kidney is involved, it is called IgG4-related kidney disease (IgG4-RKD). IgG4-related tubulointerstitial nephritis (IgG4-TIN) is a representative manifestation of IgG4-RKD. IgG4-TIN can cause obstructive nephropathy complicated by retroperitoneal fibrosis (RPF). Cases of IgG4-TIN complicated with RPF are rare. Glucocorticoids are the first-line therapeutic medication for IgG4-RD and can significantly improve renal function.
CASE SUMMARY Herein, we report the case of a 56-year-old man with IgG4-RKD complicated with RPF. The patient presented to the hospital with complaints of elevated serum creatinine (Cr), nausea, and vomiting. During hospitalization, Cr was 1448.6 µmol/L, and serum IgG4 was increased. A total abdominal computed tomography (CT) scan and enhanced CT scan obviously indicated RPF. Although this patient had a long course and renal insufficiency, we performed a kidney biopsy. Renal biopsy showed that the renal tubulointerstitium had focal plasma cell infiltration and increased lymphocyte infiltration accompanied by fibrosis. After combining the biopsy results with immunohistochemistry, it was found that the absolute number of positive IgG4+ cells per high power field exceeded 10, and the ratio of IgG4/IgG was over 40%. Finally, the patient was diagnosed with IgG4-TIN complicated with RPF and given glucocorticoids as long-term maintenance therapy, helping him keep out of dialysis. After a follow-up of 19 mo, the patient had recovered well. Previous literature on IgG4-RKD and RPF was retrieved from PubMed to characterize the clinical and pathological features and to identify the diagnosis and treatment of IgG4-RKD.
CONCLUSION Our case report demonstrates the clinical characteristics of IgG4-RKD complicated with RPF. Serum IgG4 is a favorable indicator for screening. Performing renal biopsy actively plays a vital role in diagnosis and treatment, even if the patient has a long course and manifests with renal insufficiency. It is remarkable to treat IgG4-RKD with glucocorticoids. Hence, early diagnosis and targeted therapy are essential for reversing renal function and improving extrarenal manifestations in patients with IgG4-RKD.
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Affiliation(s)
- Pei-Hua He
- The Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, Guangdong Province, China
| | - Li-Chang Liu
- Department of Nephrology, Zhuhai Hospital of Guangdong Provincial Hospital of Chinese Medicine, Zhuhai 519015, Guangdong Province, China
| | - Xing-Fu Zhou
- The Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, Guangdong Province, China
| | - Jun-Jie Xu
- The Second Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, Guangdong Province, China
| | - Wei-Hong Hong
- Department of Nephrology, Zhuhai Hospital of Guangdong Provincial Hospital of Chinese Medicine, Zhuhai 519015, Guangdong Province, China
| | - Li-Chun Wang
- Department of Nephrology, Zhuhai Hospital of Guangdong Provincial Hospital of Chinese Medicine, Zhuhai 519015, Guangdong Province, China
| | - Su-Jun Liu
- Department of Nephrology, Zhuhai Hospital of Guangdong Provincial Hospital of Chinese Medicine, Zhuhai 519015, Guangdong Province, China
| | - Jia-Hao Zeng
- Department of Nephrology, Zhuhai Hospital of Guangdong Provincial Hospital of Chinese Medicine, Zhuhai 519015, Guangdong Province, China
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Hum RM, Elyoussfi S, Parker BJ, Reid G, Kanigicherla DA. A Case of IgG4-Related Disease and Membranous Nephropathy Associated with Thrombospondin Type-1 Domain-Containing 7A. GLOMERULAR DISEASES 2022; 2:139-144. [PMID: 36751668 PMCID: PMC9710322 DOI: 10.1159/000524014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 02/14/2022] [Indexed: 11/19/2022]
Abstract
Background IgG4-related disease (IgG4-RD) is a systemic multi-organ inflammatory disorder which affects the kidney 20% of the time. Patients with intrinsic IgG4-related kidney disease (IgG4-RKD) often have tubulointerstitial nephritis (TIN) whereas glomerular lesions like membranous nephropathy (MN) are less common. Antibodies to thrombospondin type-1 domain-containing 7A (THSD7A) have been described in primary MN, but never in association with IgG4-RKD. Case Report We report the first case of IgG4-MN associated with THSD7A antibodies in serum and positivity on glomerular staining, in a 57-year-old Caucasian male with IgG4-RD affecting the pancreas, liver, lacrimal glands, extraocular muscles, and kidneys. This patient presented initially with glomerular disease including significant proteinuria consistent with MN. Glomerular staining for THSD7A antigen and serum THSD7A antibody titres was positive. Treatment with corticosteroids and cyclophosphamide successfully induced remission with resolution of proteinuria, and improvement in renal function. However, despite maintenance azathioprine, the patient relapsed 39 months later. On relapse, there was minimal proteinuria but a significant rise in creatinine. Subsequent renal biopsy showed less glomerular disease and instead a TIN pattern. Subsequent treatment with Rituximab and corticosteroids successfully induced remission. Conclusion The role of THSD7A autoantibodies in MN is emerging, and as both IgG4-MN and presence of THSD7A antibody are rare occurrences in themselves, we speculate that there may be an undiscovered association between THSD7A and IgG4-MN. Routine testing for THSD7A in IgG4-MN may help to identify the link.
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Affiliation(s)
- Ryan Malcolm Hum
- Division of Musculoskeletal & Dermatological Sciences, School of Biological Sciences, The University of Manchester, Manchester, UK,The Kellgren Centre for Rheumatology, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester, UK,Manchester Institute of Nephrology & Transplantation, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester, UK,*Ryan Malcolm Hum,
| | - Sarah Elyoussfi
- Division of Musculoskeletal & Dermatological Sciences, School of Biological Sciences, The University of Manchester, Manchester, UK,Manchester Institute of Nephrology & Transplantation, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester, UK
| | - Benjamin J. Parker
- Division of Musculoskeletal & Dermatological Sciences, School of Biological Sciences, The University of Manchester, Manchester, UK,The Kellgren Centre for Rheumatology, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester, UK
| | - Graeme Reid
- Manchester Institute of Nephrology & Transplantation, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester, UK,Department of Adult Histopathology, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester, UK
| | - Durga A.K. Kanigicherla
- Manchester Institute of Nephrology & Transplantation, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester, UK
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Adam Z, Zeman D, Čermák A, Dastych M, Doubková M, Horváth T, Skorkovská Š, Adamová Z, Řehák Z, Koukalová R, Pour L, Štork M, Krejčí M, Sandecká V, Ševčíková S, Král Z. IgG4-related disease. Clinical manifestation differential diagnosis and recent International Diagnostic Criteria for IgG4-related disease. VNITRNI LEKARSTVI 2022; 68:4-19. [PMID: 36283812 DOI: 10.36290/vnl.2022.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Immunoglobulin G4- related disease (IgG4-RD) is a rare systemic fibro-inflammatory disorder. Autoimmune pancreatitis is the most frequent manifestation of IgG4-RD. However, IgG4-RD can affect any organ such as salivary glands, orbits, retroperitoneum, prostate and many others. Recent research enabled a clear clinical and histopathological description of IgG4-RD and in 2019 four Clinical phenotypes of IgG4-related disease were described. Diagnosis is based on morphological examination with typical findings of lymphoplasmocellular inflammation, storiform fibrosis and obliterative phlebitis in IgG4-RD biopsies and the tissue invading plasma cells largely produce IgG4. Elevated serum IgG4 levels are found in many but not all patients. New diagnostic criteria for IgG4-RD have been published recently in 2019 and 2021. This review summarizes current knowledge on pathophysiology, clinical manifestations, diagnosis and differential diagnosis of IgG4-RD from the point of view 2022 and in next article brings overview of the IgG4-RD therapy.
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