Retroperitoneal Fibrosis: Still a Diagnostic Challenge

Retroperitoneal fibrosis (RPF) is a rare fibroinflammatory disorder usually involving the abdominal aorta and surrounding structures. It is divided into primary (idiopathic) and secondary RPF. Primary RPF can be immunoglobulin (Ig) G4-related disease or non-IgG4-related disease. Recently, there has been a rise in case reports regarding the topic, but awareness about the disease is still far from ideal. Hence, we present the case of a 49-year-old female who had repeated admissions for chronic abdominal pain attributed to chronic alcoholic pancreatitis. She had a medical history significant for psoriasis and surgical history significant for cholecystectomy. Her computed tomography (CT) scans on each admission for the last year showed some signs of RPF, but it was never considered the primary etiology of her chronic symptoms. We also obtained magnetic resonance imaging (MRI) which did not show any underlying malignancy but showed the progression of her RPF. She was started on a steroid regimen, which significantly improved her symptoms. She was diagnosed with idiopathic RPF due to unclear etiology, although her underlying risk factors, including psoriasis, past surgeries, and pancreatitis-associated inflammation, were considered predisposing factors. Idiopathic RPF accounts for more than two-thirds of total cases of RPF. Patients with autoimmune diseases can overlap with other autoimmune disorders. For non-malignant RPF, medical management with 1mg/kg/day steroids is deemed effective. Still, there is a lack of prospective trials and consensus for guidelines on treating RPF. The follow-up involves laboratory tests, including erythrocyte sedimentation rate, C-reactive protein, and CT or MRI in an outpatient setting to identify treatment response and relapse. There is a need for more streamlined guidelines to diagnose and manage this disease.