Pediatric idiopathic retroperitoneal fibrosis

Retroperitoneal fibrosis (RPF) is a very rare disease that is even more rare in the pediatric population. Even less common are idiopathic pediatric cases of retroperitoneal fibrosis, with a majority of reported pediatric retroperitoneal fibrosis cases being associated with secondary etiologies. We present an 11-year-old Caucasian female that was diagnosed with idiopathic retroperitoneal fibrosis using magnetic resonance imaging (MRI) to work-up severe bilateral hydronephrosis that was identified with retroperitoneal ultrasound. Given the uncommon nature of this serious condition, we present this case to illustrate the importance for physicians to include retroperitoneal fibrosis in the differential diagnosis of a pediatric patient presenting with obstructive urinary findings and understand the utility of using MRI to diagnosis and monitor this disease. Keywords: Idiopathic retroperitoneal fibrosis, Pediatric, MR

IgG4-related disease in an adolescent with radiologic-pathologic correlation

Immunoglobulin G4–related disease (IgG4RD) is an immune-mediated condition characterized by lymphoplasmacytic infiltrates and fibrosis of affected organs. IgG4RD may affect many different organs either individually or together in a multiorgan condition and, thus, incorporates a wide range of fibroinflammatory phenotypes with shared pathologic features. Although IgG4RD most commonly occurs in late adulthood, it may affect children and adolescents. Only one case of IgG4RD presenting as isolated submandibular gland involvement has been reported in the pediatric population. Radiographic features of IgG4RD are often nonspecific making diagnosis challenging, but it is important for radiologists to be familiar with this diseased as its inclusion the differential for diffuse salivary enlargement may be the first step in making an accurate diagnosis. Here, we report a case of a child presenting with bilateral submandibular gland swelling to increase awareness of this condition in the pediatric population. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors