An Overlapping Case of IgG4-Related Disease and Systemic Lupus Erythematosus

IgG4-Related Disease (IgG4-RD) Autoimmune Pancreatitis (AIP) as an Initial Presentation of Systemic Lupus Erythematosus (SLE)

Acute pancreatitis stemming from IgG4-Related Disease (IgG4-RD) seldom coincides with Systemic Lupus Erythematosus (SLE), highlighting the importance of investigating autoimmune conditions in patients with IgG4-RD. We present the case of a 57-year-old male with a medical history notable for hypertension, photosensitivity, arthritis, and malar rash, who presented with 6 weeks of persistent epigastric pain. Computed Tomography (CT) of the abdomen revealed hallmark features such as fat stranding around the pancreatic tail and gallbladder wall thickening, confirming the diagnosis of acute pancreatitis and cholecystitis. Post-cholecystectomy, histopathological examination of the gallbladder displayed IgG4-positive staining in multiple vessels, accompanied by perivascular inflammation and fibrinoid necrosis infiltrated by lymphocytes and neutrophils, confirming the diagnosis of IgG4-RD. Subsequent evaluation prompted by systemic manifestations revealed an ANA titer of 1:5120 and a dsDNA titer of 1:80, leading to the diagnosis of SLE. The patient later developed mononeuropathy, which improved upon initiation of immunosuppressive therapy. This case underscores the intricate interplay between IgG4-RD and SLE, an association documented to a limited extent in literature, thereby emphasizing the imperative of considering alternative autoimmune diseases with manifestations akin to IgG4-RD.

Discriminative features of immunoglobulin G4-related disease (IgG4-RD) and associated autoimmune rheumatic diseases (ARDs) in a nationwide observational cohort: study from the Egyptian College of Rheumatology

OBJECTIVE

The objective of this study is to present the clinical characteristics of immunoglobulin G4-related diseases (IgG4-RD) patients and describe associated overlap with autoimmune rheumatic diseases (ARDs).

PATIENTS AND METHODS

This cross-sectional study included 81 patients with IgG4-RD who were recruited from 13 specialized rheumatology departments and centers across the country in collaboration with the Egyptian College of Rheumatology (ECR). Patients underwent a thorough history-taking and clinical examination. We reviewed patients' medical records and recorded the medications they used. The presence of comorbidities or cumulative manifestations was determined. Laboratory investigations, imaging, and biopsy histopathology were assessed.

RESULTS

The mean (SD) age was 41.4 (14.6) years with 60 females and 21 males (F/M 2.9:1). The diagnosis was definite in 50 (61.7%), probable in 19 (23.5%), and possible in 12 (14.8%). The most common cumulative clinical features are IgG4-related respiratory disease in 19 (23.5%), autoimmune pancreatitis (AIP) in 18 (22.2%), and Riedel's thyroiditis in 17 (21.0%). Approximately 80% were administered corticosteroids, whereas 40% received azathioprine as adjunct therapy. Approximately 16% developed a relapse with this combination and transitioned to an alternative steroid-sparing treatment. Twelve individuals (14.7%) required rituximab. Fifty percent of patients receiving rituximab (six patients) exhibited complete improvement, while the remaining had partial improvement. Ten (12.3%) patients had associated ARDs: five (6.2%) with systemic lupus erythematosus (SLE), four (4.9%) with rheumatoid arthritis (RA), and one with vasculitis. Of the four patients with associated RA, three were rheumatoid factor (RF) negative. IgG4 was in all cases, RF was positive in 18.5%, and antinuclear antibody was in 14.7%.

CONCLUSION

IgG4-RDs exhibit a wide range of presentations, closely associated with ARDs. Awareness among clinicians about this condition will increase their consideration and rate of prompt diagnosis, which is essential to prevent damage to critical organs. Key Points • IgG4-RDs have a myriad spectrum of presentation with a close link to rheumatic diseases. • Awareness among clinicians about this condition will increase their consideration and rate of prompt diagnosis. • The lack of reliable biomarkers for this condition has been an important hurdle for diagnosis.

An Unusual Case of Overlapping Immunoglobulin G4-Related Disease and Systemic Lupus Erythematosus

Immunoglobulin G4-related disease (IgG4-RD) and systemic lupus erythematosus (SLE) are multisystemic autoimmune disorders that can present with renal manifestations. Overlapping cases of these diseases are extremely rare and present both diagnostic and therapeutic challenges. We report the case of a 70-year-old male with a history of autoimmune pancreatitis, who was admitted with fatigue, weight loss, and worsening kidney function. Laboratory tests revealed anemia with a positive Coombs test, leucopenia, elevated IgG4, hypocomplementemia, and positive results for ANA, anti-double-stranded DNA (dsDNA), anti-nucleosome, anti-RP11 antibodies, and rheumatoid factor. A spot urine sample showed subnephrotic proteinuria without hematuria. The patient met the criteria for both SLE and possible IgG4-RD, but the cause of the worsening renal function remained unclear, prompting a kidney biopsy. The biopsy revealed a lymphoplasmacytic infiltrate, storiform fibrosis, and IgG4-positive staining, consistent with IgG4-related tubulointerstitial nephritis, but without evidence of lupus nephritis. The patient was treated with prednisolone, resulting in improvement of both his symptoms and kidney function. However, significant leukopenia, anemia, and elevated anti-dsDNA titers persisted, which were presumed to be secondary to the overlapping SLE. Hydroxychloroquine and azathioprine were added to the treatment regimen, leading to improvement in cytopenias at the three-month follow-up. This case underscores the importance of kidney biopsy in suspected overlapping autoimmune diseases for identifying kidney involvement and guiding treatment, although evidence regarding optimal therapy remains limited.

An overlapping case of IgG4-related disease and systemic lupus erythematosus treated with belimumab: a case-based review

IgG4-related disease (IgG4-RD) is a systemic condition in which IgG4+ plasma cell infiltration and fibrosis cause organ swelling and lead to diverse clinical manifestations. Although IgG4-RD typically responds to glucocorticoids (GCs), relapse during tapering occurs and an early GC-sparing approach might therefore be beneficial. Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with multiple symptoms that is also treated with GCs as a first-line therapy. Recently, belimumab, a recombinant human IgG-1λ monoclonal antibody that inhibits B-cell activating factor, was approved, but reports of use for IgG4-RD are scarce. Here, we present a rare case of IgG4-RD complicated with SLE which was successfully treated with belimumab. A 67-year-old man was diagnosed with IgG4-RD based on a high serum IgG4 level and histopathological findings. Furthermore, he had pericardial effusion on echocardiography, and laboratory tests revealed thrombocytopenia, autoimmune hemolysis, positive anti-nuclear antibodies, positive anti-DNA antibodies, and hypocomplementemia. These data led to an SLE diagnosis. Treatment was started with prednisolone at 40 mg/day, plus hydroxychloroquine, which initially improved both the SLE and IgG4-RD symptoms. During the GC tapering, belimumab was added and clinical symptoms resolved completely. Our case and the literature review summarize reported rare overlapping cases of IgG4-RD and SLE and suggest that belimumab is a promising candidate for the treatment of IgG4-RD.

Overlapping Tubulointerstitial Lupus Nephritis and Immunoglobulin G4-Related Disease: A Case Report

Immunoglobulin G4-related disease (IgG4-RD) in conjunction with systemic lupus erythematosus (SLE) is a rare occurrence. In this case report, we present the case of a 50-year-old female who was diagnosed with SLE based on clinical and laboratory criteria. The patient exhibited pericardial effusion necessitating pericardiocentesis, pleural effusion requiring thoracentesis, and impaired renal function necessitating dialysis. Renal biopsy revealed findings consistent with tubulointerstitial lupus nephritis and IgG4-related disease. Additionally, elevated levels of serum IgG4 were detected. The patient received intravenous pulse dose steroids and oral steroids, which were tapered gradually, followed by daily hydroxychloroquine treatment and two doses of rituximab every two weeks. Consequently, the patient experienced an improvement in renal function and no longer needed dialysis. To our knowledge, only a few reports of this overlap exist. This late diagnosis of SLE could be explained by the fact that IgG4 is associated with milder renal disease in lupus patients, due to its inability to activate the classical complement pathway. IgG4-RD/SLE overlap patients usually respond well to a combination of steroids and other immunosuppressants used to treat SLE. However, our experience with treating this disease overlap remains limited due to its extreme rarity.

Case Report: Predominant Tubulointerstitial Lupus Nephritis or the Combination With IgG4-Related Disease?

Isolated or dominant tubulointerstitial lupus nephritis is rare. Here, we reported a 67-year-old man diagnosed with systemic lupus erythematosus (SLE) based on clinical and laboratory criteria, who was showing impaired renal function and non-nephrotic range proteinuria in the past 2 years. Renal biopsy showed almost normal glomeruli, but the tubulointerstitium showed “storiform” pattern with interstitial infiltration of IgG3 predominant plasma cells. Immunofluorescence showed linear and granular staining of IgG and C1q along TBM and interstitium. He started on medium dose of oral steroids and mycophenolate mofetil, which were gradually tapered. As a result, his renal function improved over a few days. Now, he continued on low dose steroids and mycophenolate mofetil with no evidence of relapse.

An Overlapping Case of IgG4-related Disease and Klinefelter Syndrome with Lupus-like Serological and Neurological Features: A Case Report and Literature Review

A 46-year-old man with Klinefelter syndrome (KS) presented with obliterative phlebitis of the lower legs with a deteriorated renal function, and elevated serum alkaline phosphatase and ataxia levels. Examinations demonstrated tubulointerstitial nephritis, obliterative phlebitis and lymphadenopathy with IgG4+ plasma cell infiltrate and sclerosing cholangitis. Although the serological profile and central nerve system involvement were compatible for systemic lupus erythematosus (SLE), a definite diagnosis of SLE was difficult to make. IgG4-related disease (IgG4-RD) with KS was finally diagnosed, and high dose prednisolone with intravenous cyclophosphamide was initiated and thereafter the patient demonstrated a prompt improvement. This is the first known case demonstrating overlapping IgG4-RD with lupus-like serological and neurological features in a patient with KS, thus highlighting the pathogenic role with the genomic background for IgG4-RD and SLE.