Brittle Diabetes Following Partial Pancreatectomy: A Case of Type 3c Diabetes Mellitus Complicated by Type 4 Renal Tubular Acidosis

TL;DR

A patient with a history of partial pancreatectomy developed brittle diabetes and type 4 RTA, highlighting the need for accurate diagnosis and tailored treatment.

Contribution

This case report highlights the rare co-occurrence of brittle T3cDM and type 4 RTA, emphasizing diagnostic and management challenges.

Findings

Brittle diabetes is rare in T3cDM and requires individualized therapy.

Type 4 RTA complicates diabetes management by linking hyperkalemia and hypoglycemia risks.

Multidisciplinary care is essential for managing overlapping glucose and potassium regulation issues.

Abstract

Type 3c diabetes mellitus (T3cDM), or pancreatogenic diabetes, is an under-recognized subtype of diabetes resulting from exocrine pancreatic disease or surgery. It is frequently misclassified as type 1 or type 2 diabetes, leading to inappropriate management. Brittle diabetes, characterized by severe glycemic variability and insulin sensitivity, is rare in T3cDM. Type 4 renal tubular acidosis (RTA), or hyperkalemic distal RTA, is another underdiagnosed complication of diabetic kidney disease. We report a unique case of transition to T3cDM presenting as brittle diabetes in a patient with a history of partial pancreatectomy, complicated by type 4 RTA.

This case highlights the clinical challenge of managing brittle diabetes in the context of T3cDM, a condition that often goes unrecognized in patients with a history of pancreatic surgery. The concurrent diagnosis of type 4 RTA complicated glucose and electrolyte management, as insulin is both therapeutic for hyperkalemia and a risk for hypoglycemia in brittle diabetes. Awareness of this overlap is essential, as both conditions require individualized therapy that departs from traditional inpatient diabetes management.

Clinicians should maintain a high index of suspicion for T3cDM in patients with pancreatic pathology and unstable glycemic profiles. Accurate diagnosis is key to appropriate treatment and prevention of complications. Additionally, type 4 RTA should be considered in diabetics with unexplained hyperkalemia despite preserved renal function. A multidisciplinary approach is essential for managing the complex interplay between glucose and potassium regulation in such patients.