Painful Panniculitis and Polyarthritis in Pancreatic Adenocarcinoma

Abstract

A 72-year-old man with type 2 diabetes mellitus, hypertension, osteoarthritis, and pancreatic insufficiency on enzyme replacement presented to primary care with a painful subcutaneous elbow nodule. Oral antibiotics were prescribed for presumed cellulitis and then indomethacin. However, new nodules developed, and he was admitted. Punch biopsy showed necrotizing panniculitis; 10 days after admission, he was transferred to a tertiary care center for dermatology/rheumatology consultation.Examination showed multiple exquisitely tender, erythematous, subcutaneous nodules on the extremities with several overlying joints and some draining serous fluid (Fig. 1). There were significant swelling, erythema, and warmth of bilateral ankles, right second proximal interphalangeal (PIP) joint, and right elbow with suspected synovitis. Patient also endorsed unintentional 20lb weight loss over 6 months.Notable abnormal laboratory findings included erythrocyte sedimentation rate, 56 mm/h (reference range, 0-20 mm/h); C-reactive protein, 25.1 mg/L (reference, <3.0 m/L); uric acid, 10.7 mg/dL (reference range, 3.4-7.0 mg/dL); α1 antitrypsin, 278 μmol/L (reference range, 20-50 μmol/L); creatinine, 1.2 mg/dL (reference range, 0.8-1.2 mg/dL); and angiotensin-converting enzyme, <5 U/L (reference range, 23-57 U/L). Bac terial cultures, fungal cultures, and serological testing for HIV, tuberculosis, Coxiella burnetii, syphilis, and hepatitis B/C viruses were negative. Furthermore, autoantibodies, chest radiograph, and echocardiogram were normal.Repeat biopsy was consistent with pancreatic panniculitis (Fig. 2). Ultrasound evaluation of PIPs showed flexor tendon hypoechogenicity, fibrillary pattern loss, marked peritendinous hyperemia, and effusions (Fig. 3). There were no corresponding joint effusions or synovial changes. Ankle ultrasound findings were similar.Despite no abdominal pain or any pancreatitis history, lipase was 600 U/L (reference range, 0-160 U/L), and amylase was 1166 U/L (reference range, 23-85 U/L). Computed tomography showed pancreatic fatty atrophy with no focal lesions and multiple portal vein nonocclusive thrombi. Esophagogastroduodenoscopy revealed a 1.7 Â 2.8-cm ill-defined, hypoechoic region in the pancreatic head. Fine-needle aspiration showed adenocarcinoma in association with a mucinous neoplasm. CA19-9 antigen was 936,000 U/L (reference, <35,000 U/L). Positron emission tomography/computed tomography showed mild FDG uptake in pancreatic head and in extremities with panniculitis. Oncology/ general surgery recommended neoadjuvant chemotherapy followed by Whipple procedure. The patient elected to pursue outpatient chemotherapy near home and was discharged to a nursing facility.