Immunoglobulin G4-Related Disease, A Diagnosis to Take into Account: About a Case

Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated and multisystemic condition associated with developing fibroinflammatory lesions in any organ. The diagnosis is made based on the sum of clinical, serological, radiological, and histopathological criteria; however, this is often difficult due to its similarity to neoplasms, infections, or other immune-mediated diseases. Treatment is based on corticosteroids, in a possible combination with immunomodulators. The present case concerns a 59-year-old man with a history of jaundice syndrome and weight loss, admitted for suspected malignant neoplasia of the bile duct. Imaging revealed stricture with dilation of the intrahepatic bile ducts, prominent pancreas, pancreatic duct stricture, and nodular renal lesions. Due to the history of left submandibulectomy two years before the current disease and histology compatible with Küttner's tumor, plus the high IgG4 serum values, the diagnosis of IgG4-RD was established. He started treatment with corticosteroids and was asymptomatic during follow-up.

La enfermedad relacionada con inmunoglobulina G4 (ER-IgG4) es una condición inmunomediada y multisistémica asociada al desarrollo de lesiones fibroinflamatorias en cualquier órgano. El diagnóstico se realiza bajo la suma de criterios clínicos, serológicos, radiológicos e histopatológicos; sin embargo, este suele ser difícil debido a su similitud con neoplasias, infecciones u otras enfermedades inmunomediadas. El tratamiento se basa en corticosteroides, en una posible combinación con inmunomoduladores. El presente caso trata de un varón de 59 años con historia de síndrome ictérico y baja de peso, admitido por sospecha de neoplasia maligna de la vía biliar. Las imágenes revelaron estenosis con dilatación de las vías biliares intrahepáticas, páncreas prominente, estenosis del conducto pancreático y lesiones nodulares renales. Debido al antecedente de submandibulectomía izquierda 2 años antes de la enfermedad actual e histología compatible con tumor de Küttner, más los valores elevados de IgG4 sérico, se estableció el diagnóstico de ER-IgG4. Inició tratamiento con corticosteroides y cursó asintomático durante el seguimiento.

Hypophysitis an uncommon manifestation of IgG4-related disease: Case report

IgG4-related disease is a recently described disease that can involve various organs and systems. Single organ involvement is the exception to the rule, it is generally a multi-system entity. We present a 36-year-old woman, with no previous pathological history or autoimmune disease, with headache caused by cystic macroadenoma. A transsphenoidal resection was performed and pathology documented areas of fibrosis with a predominantly plasmolymphocytic infíltrate and positive IgG4 staining in more than 20 cells per high-power field, meeting diagnostic criteria for IgG4-related sclerosing disease. Involvement of other organs was ruled out, and the patient improved clinically after management.

La enfermedad relacionada con IgG4 es una entidad recientemente descrita, capaz de involucrar diversos órganos y sistemas. El compromiso de órganos aislados es la excepción a la regla, dado que generalmente se trata de una entidad multisistémica. Se presenta el caso de una mujer de 36 años, sin antecedentes patológicos previos, en quien como causa de cefalea se documenta un macroadenoma quístico llevado a resección transesfenoidal, cuyo resultado de patología documenta zonas de fibrosis con infiltrado de predominio plasmo-linfocitario y la tinción para IgG4 positiva en más de 20 células por campo de alto poder, lo que configura criterios diagnósticos para enfermedad esclerosante relacionada con IgG4; se descartó compromiso de otros órganos y hubo mejoría clínica posterior al manejo.

The evaluation of IgG4 and IgG expression in cutaneous Rosai-Dorfman disease

Abstract Objective The authors investigated the expression of IgG4 and IgG in cutaneous Rosai-Dorfman Disease (CRDD) to further improve the understanding of this disease. Methods The authors retrospectively reviewed the clinicopathological features of 23 CRDD patients. The authors diagnosed CRDD by the presence of emperipolesis and immunohistochemical (IHC) staining of histiocytes consisting of S-100(+)/CD68(+)/CD1a(-) cells. The expressions of IgG and IgG4 in cutaneous specimens were assessed by IHC (EnVision) and quantitatively calculated by a medical image analysis system. Results All 23 patients, including 14 males and 9 females, were confirmed to have CRDD. Their ages ranged from 17 to 68 years (mean 47.91 ± 14.16). The most frequently affected skin regions were the face, followed by the trunk, ears, neck, limbs, and genitals. In 16 of these cases, the disease presented as a single lesion. IHC staining of sections showed that IgG was positive (≥ 10 cells/High-Power Field [HPF]) in 22 cases, while IgG4 was positive (≥ 10 cells/HPF) in 18 cases. Moreover, the IgG4/IgG proportion ranged from 1.7% to 85.7% (mean 29.50 ± 24.67%, median 18.4%) in the 18 cases. Study limitations In the majority of studies, as well as in the current study, the design. RDD is a rare disease, so the sample size is small. In the next studies to come, the authors will expand the sample for multi-center verification and in-depth study. Conclusion The positive rates of IgG4 and IgG and the IgG4/IgG ratio assessed through IHC staining may be important in understanding the pathogenesis of CRDD.

Progress in the diagnosis and treatment of immunoglobulin G4-related ophthalmic diseases / 国际眼科杂志(Guoji Yanke Zazhi)

Immunoglobulin G4-related diseases(IgG4-RD)are chronic, systemic diseases that have received much attention in recent years. IgG4-RD can affect almost all tissues of the body, mainly manifested by swelling and space-occupying changes in the involved sites. It is called IgG4-related ophthalmic disease(IgG4-ROD)when the lesions invade the ocular area. The disease mainly invades the lacrimal glands, orbital fat, infraorbital nerve, extraocular muscles, and eyelids. At present, the main treatment modalities for IgG4-ROD include medication, surgery, and radiation therapy, etc. With the enhanced understanding of the disease and the increasing cure rate in recent years, this article reviews the latest progress in the epidemiological characteristics, clinical manifestations, imaging features, diagnosis and treatment of IgG4-ROD.

Value of serum IgG4 and IgG4/IgG ratio in differential diagnosis of autoimmune diseases / 中国基层医药

Objective:To investigate the value of immunoglobulin G4 (IgG4) and IgG4/ immunoglobulin G (IgG) ratio in the differential diagnosis of IgG4-related diseases (IgG4-RD) and other autoimmune diseases.Methods:A total of 35 patients with IgG4-RD and 937 patients with autoimmune diseases who received treatment in Beijing Hospital from January 2021 to July 2022, and 200 subjects who concurrently underwent health checkups in the same hospital were included in this study. The IMMAGE 800 and BN II automatic special protein analyzers were used to detect IgG and IgG4. The receiver operating characteristic (ROC) curve of IgG4 and IgG4/IgG ratio was plotted.Results:Serum IgG4 level and IgG4/IgG ratio in the IgG4-RD group were 2.83 (2.01, 5.07) g/L and 25% (18%, 43%) respectively, which were higher than 0.35 (0.16, 0.72) g/L, 3% (1%, 6%) in the autoimmune disease group and 0.27 (0.14, 0.49) g/L, 2% (1%, 4%) in the healthy control group ( U = 795.50, 82.50, 1 744.50, 205.50, all P < 0.001). Taking IgG4 ≥ 1.35 g/L as the standard, patients with IgG4 ≥ 1.35 g/L in the three groups were screened out. There was a statistically significant difference in IgG4/IgG ratio between the IgG4-RD group and the non-IgG4-RD group ( U = 453.50, P < 0.001). The ROC curve of IgG4 and IgG4/IgG ratio showed that when IgG4 was 1.47 g/L, the sensitivity was 91.7%, the specificity was 83.5%, and the area under the ROC curve was 0.96. When IgG4/IgG was 12.5%, the sensitivity was 91.4%, the specificity was 85%, and the area under the ROC curve was 0.96. Taking IgG4 ≥ 1.47 g/L and IgG4/IgG ≥ 12.5% as the diagnostic criteria of IgG4-RD, the sensitivity was 94.3%, the specificity was 85.9%, and the area under the ROC curve was 0.96, which were higher than the sensitivity (87.2%) and diagnostic specificity (82.6%) provided by IgG4 alone. Conclusion:Because non-IgG4-RD diseases can also have the phenomenon of increased IgG4, when IgG4 ≥ 1.47 g/L is taken as the diagnostic criteria, its diagnostic sensitivity and specificity are the highest. Combined detection of IgG4 and IgG4/IgG ratio can increase the diagnostic efficacy of IgG4-RD.

IgG4-related disease associated with immune thrombocytopenia: A clinical case report

Autoimmune pancreatitis is a characteristic manifestation of the spectrum of the disease related to IgG4, a rare autoimmune disorder that presents clinically with obstructive jaundice due to the infiltration of plasma cells and fibrosis in the pancreas. There may be other symptoms in case of involvement of other organs, and in very rare cases there is hematological involvement. We present the case of an adult man with signs of cholestasis secondary to type I autoimmune pancreatitis, with involvement of other organs and associated with thrombocytopenia that improved with systemic corticosteroid-based immunosuppressive treatment, after which the patient showed favorable clinical and analytical evolution over time.

La pancreatitis autoimmune es una manifestación característica del espectro de la enfermedad relacionada con IgG4, trastorno raro de tipo autoinmune que se presenta clínicamente con ictericia obstructiva debido a la infiltración de células plasmáticas y fibrosis en el páncreas; puede presentarse con otra sintomatología en caso de afectación de otros órganos y en muy raras ocasiones hay compromiso hematológico. Se presenta el caso de un hombre adulto con signos de colestasis secundaria a una pancreatitis autoinmune tipo i, con compromiso de otros órganos y asociada con trombocitopenia que mejoró con el tratamiento inmunosupresor a base de corticoide sistémico, luego del cual se observó una evolución favorable en cuanto a la clínica y analítica en el transcurso del tiempo.

Cervical lymph nodes in rheumatology: A diagnostic dilemma

The case is presented on a 52-year-old male patient, who was seen in the Rheumatology department. He had painless lymph nodes in the cervical, axillary, supraclavicular, and neck region. He also had a fever, and parotid and submaxillary gland enlargement. Complementary studies were performed, showing normocytic-normochromic anemia, thrombocytopenia and eosinophilia, impaired renal function with hypoalbuminaemia and hematuria, ANA 1/5120, Sm+, ACL+. Biopsies were also performed on the compromised tissues, reaching the diagnosis of Rosai-Dorfman Disease and IgG4-related Disease. Differential diagnoses of cervical, axillary and inguinal lymph nodes, with fever, renal and hematological compromise are discussed.

Se describe el caso de un paciente varón de 52 años que consulta al servicio de reumatología por presentar adenopatías indoloras en las regiones cervical, axilar, supraclaviculares y en la nuca, así como fiebre, aumento de tamaño de parótidas y submaxilares. Se realizan estudios complementarios que arrojan como resultado anemia normocítica-normocrómica, trombocitopenia y eosinofilia, alteración de la función renal con hipoalbuminemia y hematuria, FAN 1/5.120, Sm+, ACL+ y biopsia de los tejidos comprometidos, por lo que se arriba al diagnóstico de enfermedad de Rosai-Dorfman y enfermedad relacionada con IgG4. Se discuten diagnósticos diferenciales de adenopatías cervicales, axilares e inguinales, fiebre, compromiso renal y hematológico.

Enfermedad relacionada a IgG4. Serie clínica de pacientes chilenos / IGG4-related disease. Report of 52 patients

BACKGROUND: IgG4-related disease (IgG4 RD) is an immune-mediated fibro-inflammatory disorder, with tissue infiltration of IgG4+ plasma cells. It causes pseudotumors, tumors, and a wide spectrum of clinical manifestations. AIM: To report the clinical, laboratory, histopathological and treatment characteristics of a group of Chilean patients with IgG4 RD. MATERIAL AND METHODS: Review of medical records of 52 patients aged 18 to 76 years with IgG4 RD seen at six medical centers. RESULTS: Elevated IgG4 serum levels (> 135 mg/dl) were found in 18 of 44 (41%) patients. There was histological confirmation of the disease in 46 patients. The most common sites of involvement were lungs, eyes and kidneys. Eighteen (35%) patients had only one organ involved, 34 (65%) patients had two organs and 13 (25%) patients had three or more organs. The involvement of two organs was significantly more common in men (p < 0.05). In patients with only one organ involvement, the most frequent location was orbital and meningeal. All patients with kidney or lung disease had multiorgan involvement. All patients received corticosteroid therapy, 67% synthetic immunosuppressants, and 16% rituximab. CONCLUSIONS: ER-IgG4 can affect any tissue. Multiorgan involvement was more common in this series, with preference for lungs, eyes and kidneys. An excellent response to steroids is characteristic of the disease, but with a high relapse rate that requires additional immunosuppression.

Clinical characteristics of retroperitoneal fibrosis:an analysis of 28 cases / 中华全科医师杂志

Clinical data of 28 patients diagnosed with retroperitoneal fibrosis (RPF) in Shanxi Bethune Hospital from September 2014 to September 2020 were retrospectively analyzed. There were 16 males and 12 female with a mean onset age of (56±11) years. The clinical manifestations were lumbago (16/28, 57.14%), abdominal pain (9/28, 32.14%) and back pain (8/28, 28.57%). Inflammatory indexes were elevated in 25 cases (89.29%), and 3 cases had renal insufficiency. Serum IgG4 was elevated in 3 cases (10.71%). Scheel imaging evaluation showed that proportion of type Ⅰ combined with type Ⅲ (abdominal aorta and/or iliac vascular involvement combined with unilateral or bilateral ureteral involvement) was the highest(50.00%, 14/28). followed by. Twenty-seven patients (96.43%) were treated with glucocorticoids and immunosuppressants; 14 patients (50.00%) underwent surgical intervention for ureteral obstruction or hydronephrosis; 6 patients (21.43%) relapsed during hormone withdrawal; 6 patients (21.43%) recovered from the disease and terminated medication; and 13 patients (46.43%) successfully removed the double J tube after lifting ureteral obstruction and hydronephrosis. It is suggested that RPF is more likely to occur in middle-aged and elderly men, with low back pain as the main clinical feature, and ureteral involvement as the main imaging feature. Glucocorticoid combined with immunosuppressive therapy is the conventional treatment. Surgical intervention can relieve acute obstruction and effectively improve the prognosis of patients.

Enfermedad relacionada con IgG4: reporte de un caso y revisión de la literatura / IgG4-related disease: a case report and literature review

Immunoglobulin G4 (IgG4-RD) -related disease is a regional or systemic fibroinflammatory disease of unknown etiology. It has a characteristic histopathological appearance of dense lymphoplasmacytic infiltrates with abundant IgG4 positive plasma cells, storiform fibrosis and obliterative phlebitis with the appearance of inflammatory swelling or swollen lesions. This entity frequently affects the pancreas, salivary glands, and lymph nodes, but it can compromise almost any structure in the human anatomy. This new disease entity includes a wide variety of diseases such as Mikulicz disease, autoimmune pancreatitis, Riedel's thyroiditis, interstitial nephritis, and retroperitoneal fibrosis. Glucocorticoid therapy can resolve clinical and pathologic abnormalities and impaired organ function. IgG4-RD was internationally recognized in 2011, and new evidence has accumulated on its pathogenesis, clinical characteristics, and treatment. However, much is still unknown about the behavior of IgG4 in vivo, the participation of this molecule in disease, and whether its role in IgG4-related disease is primary or secondary. The text below is based on a brief review of the most recent literature on this entity in relation to a clinical case.

Enfermedad relacionada con IgG4, según criterios ACR/EULAR 2019 sin evidencia de IgG4 en sangre / IgG4-related disease according to ACR/EULAR 2019 criteria without evidence of IgG4 in blood

INTRODUCCIÓN. La enfermedad relacionada con IgG4 es una patología fibroinflamatoria multiorgánica, de origen desconocido, que simula trastornos malignos, infecciosos e inflamatorios. Los criterios del American College of Rheumatology y la European League against Rheumatism 2019, son útiles para el diagnóstico diferencial de ésta enfermedad cuando se no se cuenta con evidencia de inmunoglobulina G4 en sangre. CASO CLÍNICO. Paciente hombre de 45 años de edad, nacido en Ambato-Ecuador, con ingreso en noviembre del 2017, en emergencias del Hospital de Especialidades Carlos Andrade Marín, con presencia de tos con hemoptisis leve, febrícula, astenia, pérdida de peso e hiporexia de dos semanas de evolución. Se realizó múltiples exámenes, tras observar infiltrados pulmonares intersticiales, con elevación de inmunoglobulina G en suero, negativas para malignidad; se sospechó de enfermedad relacionada a inmunoglobulina G4. Se ampliaron los estudios para descartar otras patologías más prevalentes y cuyo diferencial es primordial. Se inició tratamiento con prednisona y micofenolato con buena respuesta clínica; durante dos años. DISCUSIÓN. La evidencia científica registró que el hallazgo más importante en la enfermedad relacionada con inmunoglobulina G4 fue un aumento de sus niveles séricos. La recurrencia de la enfermedad en un órgano afectado o la aparición de un nuevo órgano involucrado pudo conducir al diagnóstico en el caso presentado. CONCLUSIÓN. La enfermedad relacionada con inmunoglobulina G4 al ser una patología heterogénea, inmunomediada, al simular otras afecciones puede retrasar el diagnóstico; se debe tener una alta sospecha clínica, si al excluir otros procesos infecciosos, autoinmunes y/o eoplásicos, hay evidencia de patología fibroesclerosante multiorgánica sin causa establecida.

INTRODUCTION. IgG4-related disease is a multiorgan fibroinflammatory pathology of unknown origin that mimics malignant, infectious, and inflammatory disorders. The criteria of the American College of Rheumatology and the European League against Rheumatism 2019 are useful for the differential diagnosis of this disease when there is no evidence of immunoglobulin G4 in blood. CLINICAL CASE. 45-year-old male patient, born in Ambato-Ecuador, with admission in November 2017, in the emergency room of the Hospital de Especialidades Carlos Andrade Marín, with the presence of cough with mild hemoptysis, fever, asthenia, weight loss and hyporexia of two weeks of evolution. Multiple tests were performed, after observing interstitial pulmonary infiltrates, with elevated serum immunoglobulin G, negative for malignancy; immunoglobulin G4-related disease was suspected. Studies were extended to rule out other more prevalent pathologies whose differential is paramount. Treatment with prednisone and mycophenolate was started with good clinical response; for two years. DISCUSSION. The scientific evidence recorded that the most important finding in immunoglobulin G4-related disease was an increase in its serum levels. Recurrence of the disease in an affected organ or the appearance of a new involved organ could have led to the diagnosis in the presented case. CONCLUSION. Immunoglobulin G4-related disease, being a heterogeneous, immune-mediated pathology, by simulating other conditions may delay diagnosis; a high clinical suspicion should be maintained if, when other infectious, autoimmune and/or neoplastic processes are excluded, there is evidence of multiorgan fibrosclerosing pathology without established cause.

Hypertrophic pachymeningitis, IgG4-related disease: case report / Paquimeningite hipertrófica, doença relacionada com a IgG4: relato de caso

ABSTRACT The IgG4-related disease (IgG4-RD) is a systemic disease recently characterized as an inflammatory condition generally related to the increase in serum IgG4 levels, a subclass of immunoglobulins (IgG) which corresponds to less than 6% of the total serum IgG, with singular histopathological features. The involvement of the central nervous system is rare and may be isolated or associated with other organs, mimicking tumors. Commonly, it involves the hypophysis, presenting hypophysitis as the main manifestation, but it can also affect the dura mater, presenting as IgG4-related hypertrophic pachymeningitis (IgG4-RHP). Neurological manifestations occur as a result of mass effect, typically due to vascular or nervous structures compression, resulting in functional deficits according to the anatomical site of the lesion. The main histopathological features are dense lymphoplasmacytic infiltrate, fibrosis arranged, at least focally, in a storiform pattern, and obliterative phlebitis, associated with increased numbers of IgG4+ plasma cells or an increased IgG4/IgG ratio in tissue. In this disease, the serum IgG4 levels are usually increased. The objective of this article is to report the case of a 37-year-old male patient who presented a pulsatile headache associated with diplopia and blurred vision. After radiological, histopathological and immunohistochemical studies, the diagnosis of IgG4-RHP was confirmed, besides presenting a literature review about IgG4-RD and IgG4-RHP.

RESUMEN La enfermedad relacionada con inmunoglobulina G4 (ER-IgG4) es una enfermedad sistémica recientemente caracterizada como condición inflamatoria que se relaciona con el aumento sérico de IgG4, una subclase de inmunoglobulinas (IgG) que incluye menos de 6% del total de IgG séricas, con características histopatológicas propias. El acometimiento del sistema nervioso central (SNC) es raro y puede ser aislado o asociado a otros órganos; es muy confundido con tumores. Es más común en la hipófisis, siendo la hipofisitis su principal manifestación, pero puede acometer también la duramadre, manifestándose como paquimeningitis hipertrófica relacionada con IgG4 (PHR-IgG4). Las presentaciones neurológicas se atribuyen al efecto de masa, tipicamente por compresión de estructuras vasculares o nerviosas, produciendo déficits funcionales según la ubicación anatómica de la lesión. Los hallazgos histológicos más comunes son infiltrado linfoplasmocítico denso, fibrosis (disposta, por lo menos focalmente, en un patrón estoriforme) y flebitis obliterante, además de elevación del número de células plasmáticas IgG4+ o de la proporción IgG4/IgG en el tejido. En esa enfermedad, los niveles séricos de IgG suelen estar elevados. El objetivo de este trabajo es reportar el caso de un paciente masculino con cuadro de cefalea pulsátil asociada a diplopía y visión borrosa. Luego de estudio radiológico, histopatológico y inmunohistoquímico, se obtuvo el diagnóstico de PHR-IgG4. Aún presentamos una revisión de literatura sobre la ER-IgG4 y la PHR-IgG4.

RESUMO A doença relacionada com a imunoglobulina G4 (DRIgG4) é uma enfermidade sistêmica recentemente caracterizada como condição inflamatória que se relaciona com o aumento sérico de IgG4, uma subclasse de imunoglobulinas (IgG) que compreende menos de 6% do total de IgG séricas, com características histopatológicas singulares. O acometimento do sistema nervoso central (SNC) é raro e pode ser isolado ou associado a outros órgãos; é muito confundido com tumores. É mais comum na hipófise, sendo a hipofisite sua principal manifestação, mas pode acometer também a dura-máter, manifestando-se como paquimeningite hipertrófica associada à IgG4 (PH-DRIgG4). As apresentações neurológicas são creditadas ao efeito de massa, tipicamente por compressão de estruturas vasculares ou nervosas, propiciando déficits funcionais de acordo com o sítio anatômico da lesão. Os achados histológicos mais comuns são infiltrado linfoplasmocitário denso, fibrose (em arranjo, pelo menos focalmente, de padrão estoriforme), e flebite obliterativa, além de elevação do número de plasmócitos IgG4+ ou da razão IgG4/IgG no tecido. Nessa doença, os níveis séricos de IgG4 geralmente estão elevados. O objetivo deste artigo é relatar o caso de um paciente do sexo masculino com quadro de cefaleia pulsátil associada à diplopia e turvação visual. Após estudo radiológico, histopatológico e imuno-histoquímico, foi obtido o diagnóstico de PH-DRIgG4. Apresentamos, ainda, uma revisão de literatura sobre DRIgG4 e PH-DRIgG4

IgG4-related Disease: a diagnostic challenge

Immunoglobulin IgG4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition with a characteristic histopathological appearance that can affect almost any organ. The clinical features result from a focal or diffuse appearance of a tumor-like swelling of the affected organs, identified by physical and/or imaging examination. Herein, we report the case of a 38-year-old male complaining of a worsening chronic right lumbar pain associated with legs and scrotum edema. He also had itchy and erythematous cutaneous lesions on the abdominal wall over the last 8 months, and complained of a diffuse and mild to moderate abdominal discomfort. On examination, the liver was firmly enlarged and tender. His legs had 2+ symmetrical pitting edema extending from his feet to just above the knees. An abdominal computed tomography scan showed a large mass (10 x 8 x 4cm) involving the abdominal infrarenal aorta and the iliac arteries, and compressing the inferior vena cava, with dilated iliac veins, raising the possibility of lymphoproliferative disease. During the initial investigation, the laboratory workup revealed anemia, without other marked changes. A laparoscopic-guided biopsy of the peri-aortic mass was undertaken. The histological report associated with IgG4 immunoglobulin measurement rendered the diagnosis of IgG4-RD. The patient had a favorable outcome after the use of glucocorticoids with the abdominal mass remission.

Clinical characteristics of central nervous system involvement in IgG4 related diseases / 北京大学学报(医学版)

OBJECTIVE@#To improve the understanding of the clinical characteristics of immunoglobulin G4-related disease (IgG4-RD) with central nervous system (CNS) involvement, so as to contribute to the early diagnosis and treatment.@*METHODS@#In this study, 10 patients with IgG4-RD with CNS involvement were selected. Clinical data including demographic features, clinical manifestations, organ involvement, laboratory findings, radiological results, pathology, treatments and outcomes were collected retrospectively.@*RESULTS@#Among the 10 IgG4-RD patients complicated with CNS involvement, 6 cases manifested as pituitary involvement and 4 cases manifested as dural involvement. Only 2 patients had nervous system involvement alone, while the left patients were complicated with other organ involvement besides nervous system. Half of the patients presented nervous system involvement as the initial manifestation, and the main symptoms of nervous system included polydipsia, polyuria, headache, decreased vision and so on. In the laboratory examination, the serum IgG4 level was increased in 9 cases (90.0%), and the total serum IgE was increased in 7 cases (87.5%). At the same time, their IgG, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were increased, while complement (C) 3 and C4 were decreased in some patients. Eight patients underwent tissue biopsies in different parts, the pathological examination showed a large number of lymphocyte and plasma cell infiltration, accompanied by fibrous tissue proliferation in part. All the patients were treated with glucocorticoids, and 8 cases (80%) were given immunosuppressants at the same time, and 3 cases were treated with rituximab when they expe-rienced disease relapse. As a result, 2 cases (20%) achieved complete remission (CR), and 8 cases (80%) achieved partial remission (PR). The median follow-up time was 13.5 months, and 4 cases relapsed.@*CONCLUSION@#Pituitary and dura are common affected organs of IgG4-RD with CNS involvement. Most IgG4-RD patients with CNS involvement are combined with other organ involvement, but half of them presented nervous system involvement as the initial manifestation, and the symptoms are not typical. In order to make an early diagnosis, laboratory, imaging examination and tissue biopsy should be taken into consideration in combination if necessary.

A clinical approach to hypertrophic pachymeningitis / Abordagem diagnóstica para paquimeningite hipertrófica

ABSTRACT Importance: Hypertrophic pachymeningitis (HP) is a non-usual manifestation of rheumatologic, infectious, and neoplastic diseases. Etiological diagnosis is a challenge, but when made promptly it creates a window of opportunity for treatment, with the possibility of a total reversal of symptoms. Observations: HP is an inflammatory process of the dura mater that can occur as a manifestation of sarcoidosis, granulomatosis with polyangiitis, and IgG4-related disease. The HP case evaluation is extensive and includes central nervous system imaging, cerebrospinal fluid analysis, serology, rheumatologic tests, and systemic survey for other manifestations sites. After systemic investigation, meningeal biopsy might be necessary. Etiology guides HP treatment, and autoimmune disorders are treated with corticosteroids alone or associated with an immunosuppressor. Conclusion: HP is a manifestation of several diseases, and a precise etiological diagnosis is crucial because of the difference among treatments. An extensive investigation of patients with HP helps early diagnosis and correct treatment.

RESUMO Importância: Paquimeningite hipertrófica (PH) é uma manifestação não usual de doenças reumatológicas, infecciosas e neoplásicas. O diagnóstico etiológico por vezes é um desafio, entretanto quando realizado em tempo cria uma janela de tratamento com a possibilidade de reversão total dos sintomas. Observações: A PH é um processo inflamatório da dura-máter que pode ocorrer como manifestação da sarcoidose, granulomatose com poliangeíte e doença relacionada à IgG4. A avaliação dos casos de PH é extensa e inclui imagem do sistema nervoso central, análise de líquor, sorologias, provas reumatológicas e rastreio sistêmico para doença em outros sítios. Por vezes, após toda a investigação sistêmica, a biópsia de meninge é necessária. A etiologia orienta o tratamento da HP, sendo que em doenças autoimunes adota-se o uso de corticosteroides isolados ou associados a um imunossupressor. Conclusão e Relevância: A PH é uma manifestação de várias doenças, e seu diagnóstico etiológico preciso é fundamental, visto a diferença entre os possíveis tratamentos. Uma investigação ampla nos casos de PH ajuda no diagnóstico precoce e tratamento adequado.

Renal pseudotumor: A new challenge in the diagnosis of immunoglobulin G4-related disease

Background: Immunoglobulin G4-related disease (IgG4-RD) is an immune mediated fibro inflammatory condition characterized by abundant IgG4-positive (IgG4+) plasma cell infiltrated lesions and elevated serum IgG4 concentrations. Tubulointerstitial nephritis and glomerular lesions are the most common renal IgG4-RDs. However, solitary mass lesion is rarely observed in renal IgG4-RD. Materials and Methods: We reported a 55-year-old male patient with a space-occupying lesion in the right kidney detected during a routine ultrasound medical examination. Computed tomography indicated a 20 mm × 15 mm × 18 mm mass located at the lower pole of the right kidney. Both T1-weighted imaging and T2-weighted imaging magnetic resonance imaging scans showed a hypointense mass. Diffusion-weighted imaging (b value = 800) showed slightly hyperintensity. Results: The lesion was diagnosed as renal cell carcinoma clinically based on the laboratory and radiological findings and treated with laparoscopic resection. However, the postoperative histological examination results indicated the lesion IgG4-RD of the kidney. Conclusion: We should consider pseudotumor-like IgG4-RD as a differential diagnosis for solitary renal lesion although the incidence is low

Policondritis recidivante asociada a enfermedad por IgG4 / Relapsing polychondritis associated with IgG4-related disease

La policondritis recidivante (RP) es un trastorno autoinmune sistémico poco frecuente que se caracteriza por episodio y deterioro progresivo de la inflamación del cartílago. Aproximadamente el 30% de los pacientes con RP tienen enfermedad concurrente. Sin embargo, hay tres casos previos reportados de RP relacionado con enfermedad relacionada con la inmunoglobulina G4 (IgG4-RD). Nosotros presentamos otro caso de una mujer de 37 años que desarrolló RP aproximadamente 1 año antes del diagnóstico de IgG4-RD. La asociación entre ER-IgG4 y RP sigue sin estar clara.

Relapsing polychondritis (RP) is a rare systemic autoimmune disorder characterized by the episodic and progressive deterioration of cartilage inflammation. Approximately 30% patients with RP have concurrent disease. However, there are three cases reports of RP complicated by immunoglobulin G4-related disease (IgG4-RD). Here we report another case of a 37-year-old female who developed RP approximately 1 years before IgG4-RD diagnosis. The association between IgG4-RD and RP remains unclear.

Review of a novel disease entity, immunoglobulin G4-related disease

Immunoglobulin G4 (IgG4)-related dacryoadenitis and sialoadenitis (IgG4-DS) are part of a multiorgan fibroinflammatory condition of unknown etiology termed IgG4-related disease (IgG4-RD), which has been recognized as a single diagnostic entity for less than 15 years. Histopathologic examination is critical for diagnosis of IgG4-RD. CD4+ T and B cells, including IgG4-expressing plasma cells, constitute the major inflammatory cell populations in IgG4-RD and are thought to cause organ damage and tissue fibrosis. Patients with IgG4-RD who have active, untreated disease exhibit significant increase of IgG4-secreting plasmablasts in the blood. Considerable insight into the immunologic mechanisms of IgG4-RD has been achieved in the last decade using novel molecular biology approaches, including next-generation and single-cell RNA sequencing. Exploring the interactions between CD4+ T cells and B lineage cells is critical for understanding the pathophysiology of IgG4-RD. Establishment of pathogenic T cell clones and identification of antigens specific to these clones constitutes the first steps in determining the pathogenesis of the disease. Herein, the clinical features and mechanistic insights regarding pathogenesis of IgG4-RD were reviewed.

Clinical Significance of Elevated Serum Immunoglobulin G4 Levels in Patients With Rheumatoid Arthritis

OBJECTIVE: This study aimed to evaluate the relationship between serum immunoglobulin G4 (IgG4) levels and the presence and disease activity of rheumatoid arthritis (RA).METHODS: The study enrolled 128 participants (RA, 96; healthy controls, 17; osteoarthritis, 11; and IgG4-related disease, 4) between March 2014 and July 2017. Blood samples were collected prior to the commencement of treatment, and serum IgG4 levels were determined using a nephelometric assay (levels ≥135 mg/dL were considered elevated). The levels of serum IgG4 and the ratio of IgG4/total IgG in patients with RA were compared with those in healthy controls, patients with osteoarthritis, and patients with IgG4-related disease. Furthermore, the relationship between serum IgG4 levels and RA disease activity was evaluated.RESULTS: Among the 96 patients with RA, the mean (±standard deviation) serum IgG4 level was 48.0±45.4 mg/dL; 6 (6.3%) patients had elevated serum IgG4 levels. However, none of the healthy controls or patients with osteoarthritis had elevated serum IgG4 levels. The mean serum IgG4/IgG ratio in patients with RA was 3.5%±2.8% (range, 0.2%~16.9%). Using Spearman's correlation coefficient analysis, a significant correlation was found between serum IgG4 levels and the Disease Activity Score-28 with erythrocyte sedimentation rate (r, 0.245; p=0.016).CONCLUSION: There was an increased frequency of elevated serum IgG4 levels in patients with RA, and the levels were correlated with RA disease activity.