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

18 F-FDG PET/CT in Pediatric Immunoglobulin G4-Related Disease

ABSTRACT

A 14-year-old boy presented with severe, nonintentional weight loss, fatigue, and cough. Investigations were notable for raised inflammatory markers and significantly elevated serum immunoglobulin G4 (IgG4). 18 F-FDG PET/CT was obtained for assessment of disease involvement and extent, to exclude differential diagnoses and to guide biopsy. The study demonstrated extensive FDG-avid nodal disease and multisystem organ involvement. Excisional biopsy of a right inguinal lymph node demonstrated reactive changes with numerous IgG4-positive plasma cells consistent with IgG4-related disease. He was commenced on immunosuppressive therapy with consequent weight restoration and symptom resolution.

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.

Pulmonary Nodules in Juvenile Systemic Sclerosis: A Case-Series from the National Registry for Childhood Onset Scleroderma (NRCOS)

BACKGROUND

Juvenile systemic sclerosis (jSSc) is a systemic inflammatory and fibrotic autoimmune disease. Adult guidelines recommend obtaining a screening high-resolution computed tomography scan (CT) at diagnosis. As these recommendations are adopted as standard of care for jSSc, increased screening with CT may lead to increased detection of nodules. The implications of nodules identified in jSSc are unclear and unreported.

METHODS

A retrospective chart review was performed on the prospectively enrolled National Registry for Childhood-Onset Scleroderma (NRCOS) cohort over an enrollment period of 20 years. Clinical associations with presence of nodules and nodule characteristics were investigated.

RESULTS

In this jSSc cohort, the prevalence of pulmonary nodules was 31% (n = 17 of 54). Nodule characteristics were heterogeneous, and most displayed stability over time. More participants with nodules had structural esophageal abnormalities, restriction, and reduced diffusing capacity on lung function tests, and follow-up imaging. Most participants had multiple nodules, and although most nodules were <5 mm, most participants had at least one nodule >5 mm.

CONCLUSIONS

Pulmonary nodules are seen in children with jSSc and may be related to more severe disease and/or esophageal dysfunction. More work is needed to provide guidance on radiologic follow-up and clinical management of pulmonary nodules in jSSc.

Increased 68 Ga-FAPI Activity in Benign Pulmonary Nodules

ABSTRACT

A 68-year-old man who had recently been diagnosed with pulmonary nodules underwent both 18 F-FDG and 68 Ga-FAPI PET/CT. Both studies showed increased uptake in pulmonary nodules, which are suspected to be malignant. However, based on the histopathological findings after surgery, this is ultimately diagnosed as a benign pulmonary nodule. Our case suggests that pulmonary nodules with intense 68 Ga-FAPI uptake may be benign as well.

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.