Successful treatment of pediatric IgG4 related systemic disease with mycophenolate mofetil: case report and a review of the pediatric autoimmune pancreatitis literature

Abstract

Autoimmune pancreatitis is frequently associated with elevated serum and tissue IgG4 levels in the adult population, but there are few reports of pediatric autoimmune pancreatitis, and even fewer reports of IgG4 related systemic disease in a pediatric population. The standard of care treatment in adults is systemic corticosteroids with resolution of symptoms in most cases; however, multiple courses of corticosteroids are occasionally required and some patients require long term corticosteroids. In these instances, steroid sparing disease modify treatments are in demand. We describe a 13-year-old girl with IgG4 related systemic disease who presented with chronic recurrent autoimmune pancreatitis resulting in surgical intervention for obstructive hyperbilirubinemia and chronic corticosteroid treatment. In addition, she developed fibrosing medianstinitis as part of her IgG4 related systemic disease. She was eventually successfully treated with mycophenolate mofetil allowing for discontinuation of corticosteroids. This is the first reported use of mycophenolate mofetil for IgG4 related pancreatitis. Although autoimmune pancreatitis as part of IgG4 related systemic disease is rarely reported in pediatrics, autoimmune pancreatitis is also characterized as idiopathic fibrosing pancreatitis. All pediatric autoimmune pancreatitis cases reported in the world medical literature were identified via a PUBMED search and are reviewed herein. Twelve reports of pediatric autoimmune pancreatitis were identified, most of which were treated with corticosteroids or surgical approaches. Most case reports failed to report IgG4 levels, so it remains unclear how commonly IgG4 related autoimmune pancreatitis occurs during childhood. Increased evaluation of IgG4 levels in patients with autoimmune pancreatitis may shed further light on the association of IgG4 with pancreatitis and the underlying pathophysiology.

Mycophenolate therapy in Autoimmune Pancreatitis

“…Small case series suggest steroid-sparing effects of several agents in AIP [2,6,7]. Though AZA and RTX remain commonly used, our data add to previous case reports that MMF also may be effective as a steroid-sparing agent in AIP [9][10][11][12]. MMF may be an alternative option for patients who cannot receive or are intolerant of RTX or AZA.…”

“…However data regarding efficacy and safety of MMF in AIP are lacking. As of 4-2016, less than 15 such cases have been reported in Englishlanguage literature [9][10][11][12]. AIP patients were identified by Rheumatology and Gastroenterology providers at the University of Minnesota (UMN), a tertiary referral center for patients with pancreatic diseases.…”

Management of orbital IgG4-related disease

“…Although there are myriad excellent studies published by the Asian medical community, it is unclear whether this publishing trend represents an increased prevalence of IgG4-RD in Asia, or simply an increased interest in publishing the data given an early recognition of the disease [1]. IgG4-RD appears to have a predilection for the middle-aged or older [4], though pediatric systemic and orbital IgG4-RD have been reported [5][6][7][8]. Sex may influence IgG4-RD organ involvement.…”

Evidence-based decision support for pediatric rheumatology reduces diagnostic errors

“…In 2007, a total of 81 trainees were enrolled in United States Pediatric Rheumatology three-year sub-specialty training programs; in 2015 there were 85 [1]. These numbers include foreign medical graduates who plan to return to their native countries to practice, yet even the total average number of fellows is barely keeping pace with the rate at which pediatric rheumatologists leave the work force due to retirement and decreasing clinical responsibilities [14]. Alternative approaches for increasing the availability of rheumatologist care for children, such as hiring nurse practitioners and other physician extenders [15] or use of virtual consultations using telemedicine [16] either have had minimal impact or are of unproven quality.…”