SUN-611 Diabetic Ketoacidosis As The Initial Presentation Of Type 3c Diabetes In Chronic Pancreatitis: A Rare Clinical Scenario

Abstract Disclosure: K. Conway: None. R. Reguram: None. T. Vora: None. W. Taha: None. Introduction: Chronic pancreatitis is a progressive inflammatory condition resulting in irreversible fibrosis and parenchymal loss. A known complication is secondary diabetes mellitus, termed type 3c diabetes, that typically develops gradually with mild hyperglycemia. It is uncommon for patients with chronic pancreatitis to initially present with severe hyperglycemia and diabetic ketoacidosis (DKA), a hallmark of type 1 diabetes. We present a rare case of a patient with chronic pancreatitis whose first manifestation of diabetes was DKA. Case Presentation: A 42-year-old male with alcohol use disorder, chronic pancreatitis and uncontrolled hypertension presented to the emergency department with glucose levels of 929 mg/dL. He reported two months of polydipsia, polyuria, and polyphagia but had no prior diabetes diagnosis despite multiple admissions for pancreatitis. Labs showed an anion gap of 13, bicarbonate of 20 mmol/L, beta-hydroxybutyrate of 2.93 mmol/L, serum osmolality of 317 mOsm/kg, urinalysis with >1000 glucose and 1+ ketones, and HbA1c of 16.4%. Blood gas showed pH 7.25 and bicarbonate 19.5 mmol/L. These findings confirmed DKA. C-peptide was low at 0.3 ng/mL, and autoimmune markers (GAD, islet cell, and zinc transporter antibodies) were negative. Ethanol level was undetectable. He was treated with insulin drip and fluids, and later transitioned to a basal-bolus regimen after anion gap closure. Discussion: While diabetes in chronic pancreatitis arises from progressive islet cell loss, it rarely presents with DKA, as residual beta-cell function generally persists until late disease. Furthermore, exocrine dysfunction usually predominates early, often preceding significant endocrine insufficiency. Our patient’s abrupt onset of symptomatic, insulin-deficient hyperglycemia leading to DKA is unusual in chronic pancreatitis. Negative autoimmune testing ruled out type 1 diabetes, and the low C-peptide confirmed insulin deficiency. This case emphasizes that in chronic pancreatitis, especially with risk factors like alcohol abuse and smoking, beta-cell loss may progress silently and culminate in acute decompensation. Clinicians should be aware of the potential for sudden, severe endocrine failure in such patients. Proactive glucose monitoring in chronic pancreatitis may help prevent life-threatening presentations like DKA. This case adds to the limited literature describing type 3c diabetes presenting initially as DKA. Presentation: Sunday, July 13, 2025