PSUN264 Insulin Edema: A rare side effect of Intensive Insulin Therapy

Insulin therapy associated generalized edema is a rare entity. The true incidence is unknown. It has been reported mostly in patients with poorly controlled diabetes mellitus started on intensive insulin regimens. The severity ranges from mild lower extremity swelling to anasarca. Management is primarily supportive with salt restrictions, diuretics and if possible, reduction of insulin doses. We present a case of a 39-year-old African American woman who developed generalized edema after initiation of insulin. She had history of gestational diabetes and presented to the endocrinology clinic to establish care after being hospitalized with Diabetic Ketoacidosis (DKA). She was diagnosed with diabetes mellitus initially during her pregnancy two years prior and was treated with insulin. After pregnancy, she was lost to follow up. She was then admitted to the hospital with severe DKA and was discharged on multiple daily injections of insulin. On the initial encounter in clinic, the patient endorsed developing abdominal distension and lower extremity swelling with insulin use previously so she was not using insulin consistently. Her physical examination was unremarkable. Lab work was significant for hemoglobin A1C of >15%, C-peptide 0.9 ng/mL (1.1-4.4 ng/mL), islet cell antibody 0.09 nmol/L (<0.02 nmol/L), glutamic acid decarboxylase antibody 0.40 nmol/L (<0.02 nmol/L). Her kidney and liver function were normal. She had normal thyroid function and cortisol levels. Her echocardiogram revealed normal cardiac function and she had non proliferative diabetic retinopathy on retinal exam. The patient was started on insulin and a continuous glucose monitor was placed to assess her glycemic patterns. Three days after starting insulin, she developed generalized body swelling involving face, abdomen, and lower extremities. The patient was advised to cut back on salt and started on low dose furosemide. On follow up one month later, her abdominal swelling had improved however she still had pitting lower extremity edema. On follow up two months later the edema completely resolved. Clinicians should be aware of the presentation and management of insulin induced edema. In most of the cases in literature, insulin induced edema started after starting insulin in newly diagnosed Type 1 diabetes or uncontrolled Type 2 diabetes. The pathophysiology is unclear. There is some evidence that insulin deficiency causes a catabolic state and hyperglycemia increases tissue capillary permeability. Re-introduction of insulin causes free water retention and renal excretion of sodium. This along with increased capillary permeability can lead to insulin edema. Water retention caused by the effect of counter regulatory hormones can also play a role. Insulin edema needs to be differentiated from other causes of diffuse edema. Management is generally supportive including temporarily decreasing insulin doses, salt restriction and diuretics as needed. Patient reassurance is important as well to aid in adherence to the prescribed insulin regimen. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.