Diabetes 1.5: Ketone-Prone Diabetes

Ketosis-prone diabetes mellitus: A phenotype that hospitalists need to understand

Diabetes has been classified mainly into types 1 and 2. Some type 2 diabetes patients, when developing ketosis, have been labeled as having atypical diabetes. Lately, syndromes of ketosis-prone diabetes, primarily in patients who we previously classified as type 2 diabetics, have emerged, and calls are being made to even reclassify diabetes. This mini-review will extensively deal with the historical, molecular, phenotypical, and clinical basis of why ketosis-prone diabetes is different than the traditional principles of type 1 and 2 diabetes and should be classified as such. Clinicians, especially those who are not diabetologists or endocrinologists, as well as hospitalists, intensivists, and primary care providers, will greatly benefit from this review.

Ketosis-Prone Type 2 Diabetes (Flatbush Diabetes) in Remission: A Report of Two Cases

Diabetic ketoacidosis (DKA) is a triad of uncontrolled hyperglycemia, metabolic acidosis, and increased total body ketone concentration. It is a well-known manifestation of type 1 diabetes mellitus (T1DM). However, it can also be the first presentation of type 2 diabetes mellitus (T2DM). This subtype of diabetes shares the characteristics of both T1DM and T2DM and is called 'Flatbush diabetes,' also known as 'ketosis-prone T2DM.' This article highlights the importance of early identification of ketosis-prone T2DM (KPD). We describe two cases of African American men with no past medical histories who presented with unproved DKA as the first presentation of T2DM requiring initial intensive insulin therapy, which was gradually withdrawn with the addition of metformin. Both patients are currently insulin independent for more than 15 months. It is an essential clinical entity to recognize as insulin independence positively impacts the quality of life and decreases the economic burden on the health care system. 

Prediabetes Directly Deteriorates into Diabetic Ketoacidosis and Hyperosmolar Hyperglycemic Syndrome Triggered by Acute Pancreatitis: A Case Report Illustrating a "Chicken and Egg" Paradigm in Ketosis-Prone Diabetes

INTRODUCTION

Diabetic crises occur most often in patients with type 1 diabetes and occasionally in type 2 diabetes, especially under stressful conditions. However, a diabetic crisis occurring directly from prediabetes is an unusual phenomenon.

CASE REPORT

A 45-year-old woman presented with postprandial left upper quadrant abdominal pain, nausea, and vomiting. She had a past medical history of prediabetes with impaired fasting glucose and HbA1c 6.4%. On admission, routine laboratory tests showed high anion gap metabolic acidosis (pH 6.92), anion gap 41 mmol/L, blood glucose 931 mg/dL, beta-hydroxybutyrate 28 mmol/L, and calculated effective osmolarity 322 mOsm/kg; she was diagnosed with diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic syndrome (HHS), and DKA-related abdominal pain. Later, the patient was found to have elevated lipase and amylase, and diagnosed with acute pancreatitis. Since DKA can induce abdominal pain and nonspecific lipase elevation, both of which are characteristics of acute pancreatitis, while acute pancreatitis can conversely trigger DKA, there exists a "chicken and egg" paradigm. Therefore, the differential diagnosis is discussed.

CONCLUSION

It is important to differentiate DKA from concomitant causes of abdominal pain to avoid missing the underlying etiology, which can be the trigger for DKA. During diabetic crises, treating the underlying trigger is just as important as managing metabolic derangements in order to achieve favorable outcomes; meanwhile, managing acute pancreatitis-associated hyperglycemia can promote recovery. Additionally, diabetic crisis that directly evolves from prediabetes illustrates an atypical form of diabetes called ketosis-prone diabetes; we briefly discuss its clinical characteristics, classification, and follow-up.