SUN-323 Somatostatin Analogue: An Effective Treatment for Pseudoglucagonoma Syndrome

Abstract

INTRODUCTION: Pseudoglucagonoma syndrome (PS) refers to the presence of necrolytic migratory erythema (NME), despite normal glucagon levels, and absence of a glucagon-secreting tumor. We present a case of PS successfully treated with octreotide. CASE PRESENTATION: A 42-year-old woman with history of Roux-en-Y bypass surgery, performed 14 years ago, presented to the ER with abdominal pain and rash. Two months before presentation, she took 3 days of furosemide for ankle edema. On the third day of treatment, she developed a painful rash with blisters on the feet that progressed to the arms. She stopped furosemide and consulted our ER. There, her exam showed normal vitals signs and a fatigued-appearing patient. Her skin exam was remarkable for a painful, erythematous, scaling rash with vesicles and bullae in the intergluteal cleft, upper and lower extremities. Initial labs showed decreased albumin levels (1.9 g/dl), and normocytic anemia. Skin biopsy was consistent with zinc deficiency causing acrodermatitis enteropathica vs. NME. An abdominal CT revealed a 2.6 cm mass in the pancreatic head, compatible with pancreatic neoplasm, as well as changes of pancreatitis. Lab results showed deficiency in fat-soluble vitamins, zinc and copper. Infectious and rheumatologic evaluations were negative. Two fasting glucagon levels were normal (185 ng/L and 141 ng/L). A biopsy of the pancreatic mass was unable to be performed because she refused. At this point PS was included as a differential diagnosis and the rash has not improved despite repletion of vitamins and minerals. As a result, empiric immediate-release octreotide trial was started. The starting dose was 50mcg IV twice a day and a rapid titration (1 week) to 200mcg TID over the course of 1 week. Improvement of the skin lesion were observed 24 hours after starting octreotide. DISCUSSION: PS has been associated with malignancies, liver disease, infections, malabsorption, pulmonary or renal glucagonoma and pancreatitis. The pathogenesis of NME is not clear, but is believed to be multifactorial, involving excess of glucagon, deficiency of amino acid, zinc and/or free fatty acids. One hypothesis of glucagon as a cause of NME is that glucagon induces glycogenolysis and gluconeogenesis that may lead to epidermal amino acid depletion, necrolysis, and activation of inflammatory mediators. However, octreotide has been reported to improve NME in patients without glucagonoma, demonstrating that response is independent of glucagon levels. The first step for treatment is to correct the underlying pathology. Octreotide should be considered as second line of treatment. We recommend starting with a low dose of immediate-release octreotide, and increase for a maximum dose of 200 mcg TID. This dose can be maintained until resolution of symptoms and then switched to long-acting release octreotide.