[IgG4-related systemic disease: emergence of a new systemic disease? Literature review]

IgG4-related uveitis. A French cohort and literature review

INTRODUCTION

IgG4-related disease (IgG4-RD) is a fibro-inflammatory disorder that can affect almost any organ. IgG4-related ophthalmic disease is a protean condition involving the orbit and ocular adnexa. Although a few cases of uveitis have been reported, the exact pattern of IgG4-related intraocular manifestations remains unclear. Here, we report on a nationwide French multicenter cohort of patients with IgG4-RD and uveitis and conducted a literature review.

METHODS

Patients with uveitis and a concomitant definite diagnosis of IgG4-RD (Revised Comprehensive Diagnostic criteria, American College of Rheumatology/European League Against Rheumatism classification criteria for IgG4-RD, International Consensus Diagnostic Criteria for auto-immune pancreatitis, or diagnostic criteria for IgG4-related hypophysitis), were screened from our national IgG4-RD and systemic fibrosis database. Concomitantly, we conducted a PubMed literature review and selected cases of definite IgG4-RD with uveitis.

RESULTS

We reported on 16 patients (8 from our database and 8 from the literature) and a total of 30 episodes of uveitis. Uveitis cases represented 3 % of total IgG4-RD patients in the national database on IgG4-RD and systemic fibrosis. Uveitis was inaugural in IgG4-RD in 4/16 cases (25 %) (appearing before any other IgG4-related symptom, at a median of 9 months), occurred concurrently to other IgG4-related symptoms in 9/16 cases (56 %) (at a median of 15 months before IgG4-RD diagnosis), and appeared during follow up in 3/16 patients (19 %) (at a median of 57 months after first IgG4-related symptoms). When uveitis occurred during follow up, it was associated with IgG4-RD manifestations in other organs in 6/9 patients (67 %). Uveitis was bilateral in 8/16 cases (50 %) and granulomatous in 5/10 cases (50 %). It was anterior in 8/13 (62 %), intermediate in 3/13 (23 %), and global (panuveitis) in 4/13 patients (31 %). Median serum IgG4 at diagnosis was 3.2 g/L. Median follow up time was of 6 years, during which 8/16 patients (50 %) experienced at least one relapse of uveitis. Treatment data was available for 29/30 uveitis flares. Steroids were used in 28/29 episodes of uveitis (97 %), leading to remission of uveitis in 16/28 cases (57 %). Methotrexate and rituximab (in combination with systemic steroids) were administered as second- or third-line therapy in 6/29 (21 %) and 5/29 (17 %) episodes of uveitis, respectively, and led to remission of uveitis in 4/6 cases (67 %) and 4/5 cases (80 %), respectively. One third of uveitides required at least two different lines of treatment for remission induction (mainly a combination of both systemic steroids and methotrexate or rituximab).

DISCUSSION AND CONCLUSIONS

Uveitis may be one of the initial symptoms of IgG4-RD, and IgG4-RD should be considered in the diagnostic workup of uveitis. Its early onset in IgG4-RD may help with early diagnosis and treatment of the disease. Steroid monotherapy may be sufficient to treat IgG4-related uveitis, yet relapses were frequent (50 %) and ultimately a third of patients required at least two lines of treatment. Hence, steroid-sparing agents can be considered at early stages of the disease, particularly for patients with a high risk of relapse or steroid-related complications.

[IgG4-related disease: Diagnostic criteria evolution toward the 2019 ACR/EULAR classification criteria]

The concept of IgG4-related disease (IgG4-RD) has recently been individualized in the early 2000s, but most of the organ involvements are known since more than 100 years. IgG4-RD is a non-malignant fibroinflammatory disorder, characterized by peculiar immunological and pathological abnormalities, which can affect virtually all organs or tissues. Diagnostic criteria have been proposed and have evolved rapidly, with general or organ specific criteria. An international and multidisciplinary group assembled by the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR) has recently developed and validated a set of classification criteria called 2019 ACR/EULAR classification criteria for IgG4-related disease. The objective of this review is to discuss the evolution from organ specific and general diagnostic criteria toward the 2019 ACR/EULAR classification criteria, as well as respective benefits and limits of these criteria. The use of the 2019 ACR/EULAR classification criteria will help to better define homogeneous group of IgG4-RD patients in future clinical, epidemiological and basic science research studies on the disease.

[Raynaud phenomenon with arterial thromboses and IgG4-related disease]

INTRODUCTION

This is a clinical case illustrating a diagnosis of an IgG4 related-disease (IgG4-RD) diagnosed in a vascular context.

CASE REPORT

A 47-year-old man with no past medical history consulted for a recent and disabling Raynaud phenomenon without trophic disorder. Vascular examinations revealed multiple arterial thromboses with no abnormal finger and toe pressures. Secondly, weight loss and submandibular glands enlargement appeared, leading to the diagnosis of IgG4-RD without a link being able to be established with vascular involvement. This is the second observation of this association. A French translation of the new classification criteria for IgG4-RD published in 2019 by the American College of Rheumatology and European Ligue Against Rhumatism (ACR/EULAR) is offered with direct application to the clinical case.

CONCLUSION

A Raynaud phenomenon with distal arterial thrombosis is rarely observed in the IgG4-RD.

[IgG4-related disease treatment in 2014: Update and literature review]

IgG4-related disease is an inflammatory disorder characterized by a polyclonal lymphoplasmacytic tissue infiltrate, with numerous IgG4+ plasmocytes, evolving toward fibrosis. The disease is heterogeneous and affects several tissues and organs synchroneously or metachroneously. Both the fibrosis and the tumor forming characteristics of the disease can be responsible of irreversible tissue damage. For these reasons treatment is usually necessary. A dramatic response is usually observed with steroid treatment but relapses are frequent. Immunosuppressive agents and rituximab are used as second line treatments. We review here previous studies on treatment and suggest general recommendations for the treatment and follow up of patients with IgG4-related disease.

Fibrosis of the thyroid gland caused by an IgG4-related sclerosing disease: three years of follow-up

Immunoglobulin G4-related sclerosing disease (IgG4-RSD) represents a recently identified inflammatory disorder in which infiltration of IgG4 plasma cells causes fibrosis in organs. While IgG4-RSD is well documented in the pancreas and other organs, it is poorly characterized in the thyroid gland. We report a case of a 48-year-old female with a fibrotic thyroid mass associated with a retroperitoneal fibrosis. Diagnosed early as Riedel disease, the high serum IgG4, immunohistopathology and decreased fibrosis with corticosteroid therapy, finally confirm for the first time, the origin of IgG4-RSD fibrosis of the thyroid.

[Acute pancreatitis: an overview of the management]

Over the past decades, the incidence and the number of hospital admissions for acute pancreatitis have increased in the Western countries. The two most common etiological factors of acute pancreatitis are gallstones (including small gallstones or microlithiasis) and alcohol abuse. Acute pancreatitis is associated with a significant mortality (4-10%) and 25% in case of pancreatic necrosis, especially. Edematous pancreatitis is benign and oral feeding can be restarted once abdominal pain is decreasing and inflammatory markers are improving. Enteral tube feeding should be the primary therapy in patients with predicted severe acute pancreatitis who require nutritional support. Enteral nutrition in acute pancreatitis can be administered via either the nasojejunal or nasogastric route. In case of necrosis, preventive antibiotics are not recommended. The single indication is infected necrosis confirmed by fine needle aspiration. The incidence trends of acute pancreatitis possibly reflect a change in the prevalence of main etiological factors (e.g. gallstones and alcohol consumption) and cofactors such as tobacco, obesity and genetic susceptibility. Priority is to search for associated causes, especially in cases with atypical symptoms. In case of first acute pancreatitis in patients older than 50 years, the presence of a tumor (benign or malignant) has to be specifically ruled out, using CT-scan, MRI and endoscopic ultrasound.

[Idiopathic retroperitoneal fibrosis: a multicentric retrospective study of 30 French cases and follow-up of the renal function]

PURPOSE

Idiopathic retroperitoneal fibrosis (IRF) is an inflammatory disorder, affecting the aorta and the surrounding vessels and tissues. The prognosis is mainly driven by the risks of chronic kidney disease and relapse. Our aim was to assess the prevalence of chronic kidney disease at follow-up.

METHODS

We retrospectively reviewed the medical records of patients diagnosed for IRF in Seine-Saint-Denis (France) between 1987 and 2011. We collected informations about presentation, radiologic findings and follow-up. Diagnosis of IRF was confirmed when all the following criteria were met: infiltration of the infrarenal aorta or iliac vessels, absence of aneurysmal dilation, lack of clinical suspicion of malignancy.

RESULTS

Thirty patients were identified, with a male/female ratio of 4.9. Mean age was 55±13 years old. The mean creatinine clearance was 66 mL/min/1.73 m(2) and the mean CRP was 45±36 mg/L. In 24 (80%) patients, the location of IRF was periaortic and periiliac. Eleven patients (37%) underwent a diagnostic biopsy, and 14 (47%) required an ureteral procedure. A mean follow-up of 63 months was available for 29 patients: 69% relapsed, 7 developed chronic renal disease (24%), and one died of urinary sepsis. Older age (P=0.023), diabetes (P=0.007), and initial renal insufficiency (P=0.05) were associated with a risk of chronic renal insufficiency.

CONCLUSION

The high frequency of relapses and chronic renal disease emphasizes the need of close follow-up in patients diagnosed with IRF.

PRSS1_p.Leu81Met mutation results in autoimmune pancreatitis

AIM: To describe protease serine 1 (PRSS1) gene mutations in patients with autoimmune pancreatitis (AIP) and the clinical features of AIP.

METHODS: Fourteen patients with AIP, 56 with other chronic pancreatitis, 254 with pancreatic cancer and 120 normal controls were studied. The mutations and polymorphisms of four genes involved with pancreatitis or pancreatic cancer, PRSS1, SPINK1, CFTR and MEN1, were sequenced. The pathogenic mechanism of AIP was investigated by comparing the wild-type expression system with the p.81Leu→Met mutant expression system.

RESULTS: Two novel mutations (p.81Leu→Met and p.91Ala→Ala) were found in PRSS1 gene from four patients with AIP. PRSS1_p.81Leu→Met mutation led to a trypsin display reduction (76.2%) combined with phenyl agarose (Ca²⁺ induced failure). Moreover, the ratio of trypsin/amylase in patients with AIP was higher than in the patients with pancreatic cancer and other pancreatitis. A large number of lymphocytes and plasma cells were found in the bile ducts accompanied by hyperplasia of myofibroblasts.

CONCLUSION: Autoimmune pancreatitis may be related to PRSS1 gene mutations.

IgG4-related multiorgan disease: report of the first autopsy case

IgG4-related disease (IgG4RD) is a chronic recurring fibro-inflammatory pathology that is considered to be of autoimmune origin. Histopathology is considered to be the gold standard method for diagnosis. IgG4RD affects multiple organs. IgG4RD was first identified in the pancreas and was called autoimmune pancreatitis (AIP). During the following years, the disease spectrum was expanded and it was realised that the extrapancreatic lesions can precede, coexist or appear after the diagnosis of AIP. At present, several illnesses such as Mikulicz disease, Küttner tumour, multifocal fibrosclerosis, etc, are considered to be part of the IgG4RD spectrum. The symptoms of the disease tend to appear over months and years and diagnosis is achieved on average 13.5 months (4-60 months) after the onset. The purpose of this report was to provide information about a case that was sadly fatal but that permitted a complete histopathological study of the damaged tissues.

[Diagnosis of IgG4-related systemic disease in a patient with an ocular tumor associated with lung nodules]

The IgG4-related systemic disease is a recently described entity of fibro-inflammatory systemic damage. Although initially described in some forms of pancreatitis, the disease can affect all organs. The common histological features include a lymphoplasmacytic infiltration (especially to IgG4), fibrosis and phlebitis. Elevated serum level of IgG4 is also often present. This rare but certainly underdiagnosed disease must be kept in mind of all clinician faced to a non-specific inflammatory lesion. We report a case of ocular inflammation and lung tumors in a patient of 84 years for which the diagnosis was made through immunolabelling with IgG4 in lesions biopsied.

[Mesenteric panniculitis]

Mesenteric panniculitis is a nonspecific inflammatory process affecting the fatty tissue at the root of the mesentery. This term is also used to describe the clinical and imaging findings in this disorder. Mesenteric panniculitis can be a misleading term: it is commonly misused to design an increased density of the mesentery without prejudice regarding the etiology. Pain is the main clinical symptom. Half of the patients are asymptomatic. There is a palpable mass in half of cases. Laboratory tests sometimes reveal an acute phase reaction of varying intensity. Mesenteric panniculitis is suspected when CT scan shows increased density of the mesenteric fat. Nevertheless, only histological examination could establish the diagnosis. Histologic examination may reveal various stages: lipodystrophy (the first stage when fat necrosis is predominant), mesenteric panniculitis (a majority of infiltrating lymphocytes), sclerosing mesenteritis (the end stage when fibrosis is predominant). Histopathologic differential diagnoses are lymphomas, lipomas, liposarcomas that can mimic mesenteric panniculitis on CT scan. Mesenteric panniculitis is associated with various diseases, especially with intra-abdominal inflammatory process. It also can be idiopathic. Rare complications can occur with vascular or digestive tract compressions. Empirical treatment is only useful in symptomatic patients. Colchicine, corticosteroids or immunosuppressive agents can be used. The only interest of surgery is the histological confirmation of the diagnosis. A better understanding of the pathophysiology of the immunoregulatory functions of adipose tissue will improve mesenteric panniculitis management.

[IgG4-related disease and renal and urological involvement]

Hyper-IgG4 syndrome, or IgG4-related disease, is an emerging disorder, involving one or more organ(s), and characterized by "storiform" fibrosis and inflammatory lesions with a predominance of IgG4+ plasma cells and increased IgG4 serum levels. Since the first report of auto-immune pancreatitis, numerous organ lesions have been reported and have been found to occur in a same patient including: sialadenitis, dacryoadenitis, lymphadenopathy, liver and biliary tract involvement, and renal and retroperitoneal lesions. Renal involvement was first described in 2004 and usually presents as functional and/or morphological abnormalities. In most cases, renal pathological analysis reveals tubulointerstitial nephritis that is rarely associated with glomerular lesions. Retroperitoneal fibrosis is also a typical feature that may be associated with periaortitis or inflammatory abdominal aortic aneurysm. First line treatment is based on corticosteroid therapy. Short-term outcome is usually favorable. However, patients should be carefully monitored for relapses and long-term complications. Although the multiple organ lesions share common clinical, biological, radiological and pathological features, no consensus diagnostic criteria have yet been validated for IgG4-related disease. Ruling out differential diagnoses is thus mandatory. Our literature review provides nephrologists, urologists and pathologists with key elements that will help in the early diagnosis and proper management of this new and emerging disorder.