Autoimmune pancreatitis and primary sclerosing cholangitis in a 16-year-old boy with inflammatory bowel disease

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.

Can IgG4 Levels Identify the Ulcerative Colitis Subtype of Inflammatory Bowel Disease?

Background

Pancreatitis and exocrine pancreatic insufficiency may occur as extraintestinal manifestations of inflammatory bowel disease. Recently, autoimmune pancreatitis and colitis have been described as presentations of IgG4-related disease. IgG4+ plasma cells have been identified in colon tissue from patients with refractory forms of inflammatory bowel disease. The presence of elevated serum/tissue levels of IgG4 and the frequency of exocrine pancreatic insufficiency in inflammatory bowel disease are still a source of controversy. Our aim was to investigate the meaning of elevated IgG4 levels in patients with inflammatory bowel disease.

Methods

A cross-sectional study analyzed 56 patients with a diagnosis of inflammatory bowel disease recruited by convenience sampling from two tertiary centers in Midwestern Brazil. All patients underwent fecal pancreatic elastase testing for detection of exocrine pancreatic insufficiency and serum IgG4 measurement. Findings were correlated with clinical and epidemiological data and disease activity.

Results

Elevated serum IgG4 levels were found in 10 patients, and were most frequent in ulcerative colitis (nine cases), with a prevalence ratio of 16.42 (95% CI: 3.32 - 79.58). Ten patients (10 of 56, 17.8%) were diagnosed with exocrine pancreatic insufficiency, which did not correlate with disease activity, and serum IgG4 levels.

Conclusion

Exocrine pancreatic insufficiency is prevalent in patients with inflammatory bowel disease, but it is not associated with elevated serum IgG4 levels. The high prevalence of elevated serum IgG4 in ulcerative colitis suggests that this parameter has potential for use as a diagnostic biomarker.