Pediatric IgG4-related disease: a descriptive review

INTRODUCTION

IgG4-related disease (IgG4-RD) is an immune-mediated systemic fibroinflammatory condition characterized by serum IgG4 elevation and IgG4-positive plasma cell infiltration into various organs. It generally occurs in elderly males. Pediatric cases have been reported, albeit rarely, accordingly lack of recognition of such cases could delay therapeutic intervention leading to poorer outcomes.

AREAS COVERED

The present review is a descriptive review of all published case reports, cohort studies, and reviews of pediatric IgG4-RD listed in PubMed. Characteristics of pediatric IgG4-RD were clarified, including sex, organ involvement, serological and histological findings, and treatment. We assessed how many published cases met current classification and comprehensive diagnostic criteria.

EXPERT OPINION

The characteristics of pediatricIgG4-RD differed from adult IgG4-RD in terms of sex and involved organs. There was no clear male dominance in numbers of cases, and surface organ involvement such as ophthalmic diseases were more common in the pediatric IgG4-RD. Organ involvement tended to be indolent and unilateral, causing difficulty in definitively diagnosing pediatric IgG4-RD. Only about 20% of published cases met IgG4-RD classification or comprehensive diagnostic criteria. Physicians should be careful in diagnosing pediatric IgG4-RD after excluding mimickers. International collaboration toward high-quality evidence to support diagnosis and treatment of pediatric IgG4-RD is advised.

IgG4 related pericardium and lung disease in pediatric patient complicated with fatal massive hemoptysis: a case report and review of literature

BACKGROUND

IgG4-related disease (IgG4-RD) is a progressive and sometimes fatal disease that rarely affects pediatric age group. It may affect the orbits, lacrimal and salivary glands, pancreas, kidneys, peritoneum and other organs. Lung and pleura are not commonly reported in IgG4-RD. We here present a rare case of pediatric IgG4-RD with rare involvement of pericardium, pleura and lungs.

CASE PRESENTATION

A 13-year-old girl presented with intrathoracic IgG4-RD with pleuropericardial involvement. She showed initial improvement on prednisolone. Azathioprine and then mycophenolate failed to control relapses during steroid tapering. Her last relapse was treated by rituximab however, the patient developed acute fatal massive hemoptysis.

CONCLUSIONS

Pediatric IgG4-RD is a rare entity with pericardio-pulmonary affection as the rare of the rare. Usual treatment of prednisolone and steroid sparing agents should be used, with rituximab used as a rescue therapy, but fatal complications may occur.

Clinicopathologic Characterization of IgG4-Rich Pediatric Head and Neck Lesions

CONTEXT.—

Immunoglobulin G4 (IgG4)-related disease is rare but well characterized in adults; however, the clinical and histologic manifestations in children may differ.

OBJECTIVE.—

To review the clinical and histologic features of IgG4-rich head and neck lesions in a pediatric population.

DESIGN.—

Retrospective search for cases with IgG4 immunohistochemical staining performed at our institution from 2011 to 2019. Review of clinical courses, serology profiles, histologic patterns, and immunohistochemical staining patterns.

RESULTS.—

Four pediatric IgG4-rich lesions were identified and showed distinct histologic patterns from adult IgG4-related disease, including absence of pathognomonic findings associated with the latter. One case showed intralesional immunoglobulin light-chain restriction. Clinical review showed serum IgG4 elevation in 2 of 4 cases, presence of additional autoantibody positivity, and a generally benign/treatment-responsive clinical course.

CONCLUSIONS.—

Pediatric IgG4-related disease shows distinct clinical, serologic, and histologic features from its adult counterpart. Pediatric IgG4-related disease involving the orbit has unique clinical characteristics, including frequently normal serum IgG4 levels and female predominance. Awareness and evaluation for these features may improve diagnosis and treatment.

A Case of Tracheal Stenosis as an Isolated Form of Immunoproliferative Hyper-IgG4 Disease in a 17-Year-Old Girl

Immunoglobulin G4-related disease (IgG4-RD) is a lymphoproliferative disease which is described almost exclusively in adults. There are only a few pediatric patients who have been observed with this disorder. Here, we describe a rare case of IgG4-RD in a 17-year-old girl with a single manifestation—tracheal stenosis without previous intubation or other inciting event. She had mixed dyspnea and noisy and weakened breathing. Immunoproliferative hyper-IgG4 disease was diagnosed, based on elevated serum IgG4 and histological findings. Until now we have chosen to treat the girl only with corticosteroids with a good response so far. The general condition as well as the respiratory function are regularly monitored. The tracheal involvement of IgG4-RD is uncommon. Nonetheless, it is a manifestation that should be included in the differential diagnosis of tracheal stenosis.

FDG-Avid Pulmonary Nodules and Tracheobronchial Mural Inflammation in IgG4-Related Disease

ABSTRACT

We report the case of a 9-year-old girl who presented with acute fevers, cough, and epistaxis with nasal swelling, and found to have a nasal mass. On 18F-FDG PET/CT, she was found to have marked nodal and pulmonary parenchymal disease with diffuse and symmetrical mural FDG uptake within the trachea and bronchial tree. The differential diagnosis was broad, and she was diagnosed with IgG4-RD (IgG4-related disease) and improved on appropriate treatment. To our knowledge, there are only 2 other pediatric cases of IgG4-related pulmonary disease in the literature, and our case serves as a unique constellation of intrapulmonary IgG4-RD imaging findings.

Plasma cell-rich bronchoalveolar lavage fluid: Could be a first clue to IgG4 plasma cell-related lung disease

Plasma cells are usually absent in normal bronchoalveolar lavage (BAL) fluids. Frequent plasma cells in BAL are always pathologically significant. They raise a rather narrow differential diagnosis, predominantly extrinsic allergic alveolitis and few other interstitial lung diseases. BAL is a key diagnostic procedure for certain lung diseases. Because plasma cells are uncommon in BAL fluids and usually associated with limited conditions compared to other more common interstitial lung diseases, the focus of cell count differentials in BAL fluids was on other mononuclear and granulocytic inflammatory cells. Recently, cases of IgG4 positive plasma cell-related lung diseases have been reported in tissue specimens. This may raise the importance of cytologically recognizing plasma cells in BAL fluids. We report a case of a 16-year-old boy with clinical and radiologic features of diffuse interstitial lung disease. His BAL cytology showed frequent plasma cells. Endobronchial biopsy showed substantial infiltration by plasma cells confirmed by immunohistochemistry. After excluding other lung diseases, the possibility of IgG4 plasma cell-related disease was raised. Blood tests showed elevated serum levels of IgG4. This case emphasizes the importance of including of IgG4 plasma cell-related lung disease as a possible differential diagnosis. This should prompt proper serologic tests for confirmation and appropriate management. With increasing reports of IgG4-related lung disease, cytopathologists should be aware of this possibility when examining BAL fluids. Measurement of IgG levels in BAL fluids and plasma cell immunophenotyping might be promising tools.

Autoimmune Pancreatitis and Ulcerative Rectocolitis in an Adolescent

Autoimmune pancreatitis (AIP) is rare in teenagers and difficult to diagnose. There are no clear and established diagnostic criteria in the pediatric population to distinguish subtype 1 and subtype 2. Here, we report the case of a 16-year-old white French teenager admitted to the pediatric emergency service with more than 1 year's history of pain originating from the epigastric and the right hypochondriac regions, with bloody diarrhea. After exclusion of pancreatic cancer and other common causes of acute pancreatitis, the diagnosis of AIP was suspected. Biological analyses revealed acute pancreatitis with severe cholestasis and an elevated level of serum immunoglobulin G4. Magnetic resonance cholangiography revealed a voluminous pancreas presenting a typical "sausage-like" aspect. Anatomopathological analyses of the liver biopsy specimen revealed a biliary obstruction due to pancreatic involvement without the typical aspect of chronic destructive cholangitis. Corticotherapy and immunosuppressive treatment proved effective after 1 week of treatment. Without a pancreatic biopsy specimen, the distinction between AIP type 1 and 2 could not be made clearly in this case. The succession of clinical observations could allow clinicians to recognize, treat, and manage AIP in children.

An initial exploration for comprehensive assessment of IgG4-related lung disease: analyses on the cases enrolled from a systematic review

Background

The existence of two diagnostic systems, the Boston and Japan criteria, for immunoglobulin G4-related disease (IgG4-RD) confuse the medical practice. We aimed to develop a comprehensive assessment based on the weight of each diagnostic item in the existing criteria to improve the diagnostic efficiency of Boston criteria.

Methods

We assessed the patients enrolled by a systematic review of the literatures using the Boston criteria, Japan criteria and a tentative comprehensive assessment respectively, and evaluated the efficiency of each system and their consistency.

Results

Our analysis showed that the distinction in pathological diagnostic items was similar for the Boston criteria (IgG4+/IgG+ ratio, P<0.01; the number of pathological features and IgG4+ count, P<0.001) and comprehensive assessment (IgG4+/IgG+ ratio and the number of pathological features, P<0.001; IgG4+ count, P<0.05). For the Japan criteria, a good distinction in the number of pathological features was demonstrated (P<0.05) but the difference in the IgG4+/IgG+ ratio and IgG4+ count was not significant. There was relatively poor consistency between the Boston and Japan criteria (Kappa =0.482, P<0.001), while there was good agreement (Kappa =0.811, P<0.001), but a significant difference (P=0.011, McNemar matching test), between the Boston criteria and comprehensive assessment.

Conclusions

The current two diagnostic systems have poor consistency. Comprehensive assessment has good agreement with the Boston criteria, but can identify those cases in Boston Category 3 who could still be diagnosed as IgG4-related lung disease. Considering the weight of diagnostic items, the scoring system is a tentative exploration that should be improved with further experience in diagnosing IgG4-related lung disease.

Association of immunoglobulin G4 and free light chain with idiopathic pleural effusion

The cause of pleural effusion remains uncertain in approximately 15% of patients despite exhaustive evaluation. As recently described immunoglobulin (Ig)G4-related disease is a fibroinflammatory disorder that can affect various organs, including the lungs, we investigate whether idiopathic pleural effusion includes IgG4-associated etiology. Between 2000 and 2012, we collected 830 pleural fluid samples and reviewed 35 patients with pleural effusions undiagnosed after pleural biopsy at Yamaguchi-Ube Medical Center. Importantly, IgG4 immunostaining revealed infiltration of IgG4-positive plasma cells in the pleura of 12 patients (34%, IgG4⁺ group). The median effusion IgG4 level was 41 mg/dl in the IgG4⁺ group and 27 mg/dl in the IgG4^- group (P < 0·01). The light and heavy chains of effusion IgG4 antibodies of patients in the IgG4⁺ group were heterogeneous by two-dimensional electrophoresis, indicating the absence of clonality of the IgG4 antibodies. Interestingly, the κ light chains were more heterogeneous than the λ light chains. The measurement of the κ and λ free light chain (FLC) levels in the pleural fluids showed significantly different κ FLC levels (median: 28·0 versus 9·1 mg/dl, P < 0·01) and κ/λ ratios (median: 2·0 versus 1·2, P < 0·001) between the IgG4⁺ and IgG4^- groups. Furthermore, the κ/λ ratios were correlated with the IgG4⁺ /IgG⁺ plasma cell ratios in the pleura of the IgG4⁺ group. Taken together, these results demonstrate the involvement of IgG4 in certain idiopathic pleural effusions and provide insights into the diagnosis, pathogenesis and therapeutic opportunities of IgG4-associated pleural effusion.

Pulmonary manifestation of immunoglobulin G4-related disease in a 7-year-old immunodeficient boy with Epstein-Barr virus infection: a case report

BACKGROUND

Immunoglobulin G4-related disease (IgG4-RD) is a multiorgan fibroinflammatory condition with lymphoplasmacytic infiltrates containing abundant IgG4-positive plasma cells. The immunopathogenesis of the disease and the potential role of triggering autoantigens or infectious factors have not been clearly defined. Immunoglobulin G4-related lung disease is a new and emerging condition in pediatric patients and to date, there have been only two reports regarding pulmonary manifestation of IgG4-RD in children recently published. This is the first report of IgG4-related lung disease in an immunodeficient child with Epstein-Barr virus infection.

CASE PRESENTATION

We report on the case of a 7-year old atopic boy who was hospitalized with an initial clinical and radiological diagnosis of pneumonia, positive Epstein-Barr virus (EBV)-DNA in the blood and defective adaptive immunity. The lung CT showed a consolidated mass lesion adjacent to the posterior wall of the chest and the diaphragm. The child underwent surgical resection of the tumor, and the histologic examination of the lung specimens revealed lymphoplasmacytic infiltrates with fibrosis and vasculitis correlating with IgG4-related lung disease. Subsequent monitoring of the patient with lung CT, pulmonary function tests and IgG4 levels did not show signs of active disease.

CONCLUSIONS

The diagnosis of IgG4-related lung disease in children is challenging because of its rarity, nonspecific symptomatology and heterogeneous morphological manifestations. Further studies are required in children with pulmonary presentation of IgG4-RD to better understand pathogenesis of this condition, possible immunological or infectious triggering factors, and finally, to determine pediatric patient-targeted therapeutic interventions.

IgG4-related disease: a systematic review of this unrecognized disease in pediatrics

BACKGROUND

Immunoglobulin G4-related disease (IgG4-RD) is a systemic fibro-inflammatory condition with an unclear pathophysiological mechanism affecting different parts of the body. If untreated, the disease can lead to fibrosis and irreversible organ damage. IgG4-RD mostly has been described in adults, hence it is generally unknown among pediatricians. This systematic search of the literature provides an overview of all reports published on IgG4-RD in children in order to create awareness of IgG4-RD in pediatrics and to emphasize the broad clinical presentation of this disease.

METHODS

A systematic literature search of Embase, Medline, Web-of-Science, PubMed publisher, Cochrane and Google Scholar was performed for case reports on IgG4-RD in children.

RESULTS

Of total 740 articles identified by the search, 22 case reports including 25 cases of IgG4-RD in children were found. The median age of the children was 13 years, of which 64 % were girls. IgG4-related orbital disease (44 %) and autoimmune pancreatitis type 1/IgG4-related pancreatitis (12 %) predominantly occurred. Less frequently, other manifestations as pulmonary manifestation, cholangitis and lymphadenopathy were also found. Almost all cases were histologically proven. Prednisone was the first choice of treatment leading to favorable clinical response in 83 % of the cases. Maintenance therapy with steroid sparing agents was required in 43 % of the cases needing therapy. Rituximab was successful in all 4 cases, whereas, the disease modifying rheumatic drugs (DMARDs) mycophenolate mofetil, azathioprine and methotrexate were effective in almost 50 % of the cases.

CONCLUSION

IgG4-RD in children is a generally unknown disease among pediatricians, but several pediatric cases have been described. Prednisone is the first choice of treatment leading to disease remission in the majority of the cases. DMARDs and rituximab are alternative effective steroid sparing agents with more positive evidence for the latter.

Severe IgG4-Related Disease in a Young Child: A Diagnosis Challenge

Immunoglobulin G4-related disease (IgG4-RD) is an increasingly recognized syndrome that can appear with multiple organ involvement, typically with tumor-like swelling, lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells, and elevated serum IgG4 concentrations. We report the case of a 22-month-old female child with failure to thrive and recurrent respiratory tract infections since 8 months of age. Physical examination was normal except for pulmonary auscultation with bilateral crackles and wheezes. Laboratory tests revealed elevated erythrocyte sedimentation rate, and elevated serum IgG and IgG4 with polyclonal hypergammaglobulinemia. Thoracic CT and MRI showed multiple mediastinal lymphadenopathies and a nodular posterior mediastinal mass in right paratracheal location with bronchial compression. Initial fine needle aspiration biopsy was compatible with reactive lymphadenopathy but after clinical worsening a thoracoscopic partial resection of the mass was performed and tissue biopsy revealed lymphoplasmacytic infiltrate and increased number of IgG4-positive plasma cells and a ratio of IgG4/IgG positive cells above 40%. Glucocorticoids therapy was started with symptomatic improvement, reduction in the size of the mass, and decrease of serum IgG4 levels after 6 weeks. There are very few reports of IgG4-RD in children. Long-term follow-up is necessary to monitor relapses and additional organ involvement.

Structural properties of adenovirus DNA's

The current study presents the case of a 9-year-old Chinese boy who presented with eosinophilia and elevated serum levels of immunoglobulin G4 (IgG4). A bone marrow puncture identified an elevated eosinophil rate of 23% (normal range, <5%), which indicated eosinophilia. However, gene analysis, fluorescent in situ hybridization and other examinations, including bone marrow aspiration, blood routine, auto-antibody tests and parasitic and allergens screening, contradicted a diagnosis of secondary or clonal eosinophilia. Furthermore, the patient exhibited multiple lymph node swelling and a lymph biopsy strongly indicted a pathological diagnosis of IgG4-related disease (IgG4-RD). His peripheral blood flow cytometry confirmed an elevated count of plasmablasts, which is specific to IgG4-RD. The patient responded well to therapy with prednisone and remained healthy in all follow-ups. By taking all these factors into consideration, the boy was diagnosed with IgG4-RD. It is difficult to distinguish IgG4-RD from hypereosinophilic syndrome and the potential association between the two remains unclear. However, the present case study serves as a reminder that IgG4-RD may occur in children and medical professionals should not neglect this possibility.