A Case Report of Mesenteric Panniculitis and Fibrous Dysplasia with Primary Metabolic Syndrome.

Introduction: Mesenteric panniculitis (MP) is a rare clinically diagnosed disease resulting from fibro-inflammation in the intestinal adipose tissue. Precedent intra-abdominal inflammation or trauma is often evident. Fibrous dysplasia (FD) is a benign uncommon childhood disease of the bones, with fibrous connective tissue replacing bone tissue. FD can cause pain, disfigurement, and entrapment of critical neighbouring structures. Adult-onset craniofacial involvement is rare. Metabolic syndrome is characterized by obesity and chronic subclinical inflammation, promoting abnormal cellular fibrosis and proliferation. The concomitant incidence of MP and FD in an older female adult with metabolic syndrome is unprecedented. An aberrant metabolic contributory pathophysiology for both MP and FD could be postulated. Case Report: A 60-year-old Caucasian woman with primary long-standing well-treated metabolic syndrome with obesity presented for revision bariatric surgery. She had previous intra-abdominal surgeries and occasional intermittent abdominal pain. The surgery was abandoned due to extensively inflamed intestinal mesentery. Radiological studies and intra-abdominal biopsy confirmed MP. She subsequently developed pronounced unilateral facial swelling and radiological studies confirmed FD. Treatment has been suboptimal for both MP and FD. She developed venous thromboembolism on tamoxifen treatment for MP. The patient currently reports abdominal pain and swelling from MP, and facial disfigurement, pain, and tinnitus from FD. Blood markers for inflammation have remained consistently high, and there is statin intolerance. Most recently liver steatosis and diabetes have developed. Conclusion: A case of MP and FD with primary metabolic syndrome is unique. An increased awareness of such rare cases could lead to further research, and critically needed treatments to optimize outcomes. LEARNING POINTS: Mesenteric panniculitis (MP) is a rare disease as is craniofacial fibrous dysplasia (FD) in adults. The incidence of these two rare diseases in an older adult with primary metabolic syndrome is previously unknown, making this case the first of its kind.Metabolic syndrome is common condition of the industrialized population, and an aberrant common "systemic" metabolic pathophysiology could contribute significantly to the inflammatory and fibrotic cellular changes inherent to both these two localized diseases of MP and FD.Knowledge about rare diseases, particularly if clustered with a primary systemic disease, could lead to better treatment outcomes in the future and promote novel therapeutic targets.