Differential Diagnosis for 64-year-old Female with Diabetes

The patient presents with dizziness, nausea, vomiting, low blood pressure (96/70), tachycardia (pulse rate 108), and an arterial pH of 7.12, indicating acidosis. Given her diabetes and the medications listed (Farxiga, Byetta, glipizide, linagliptin, nateglinide), we can categorize the differential diagnosis as follows:

• Single Most Likely Diagnosis

  • SGLT2 inhibitor (Farxiga) induced euglycemic diabetic ketoacidosis (DKA): The patient's presentation of acidosis (pH 7.12), nausea, vomiting, and hypotension, along with tachycardia, is highly suggestive of diabetic ketoacidosis. SGLT2 inhibitors like Farxiga are known to increase the risk of euglycemic DKA, a condition where the blood glucose levels may not be as high as typically seen in DKA but still presents with significant metabolic acidosis.

• Other Likely Diagnoses

  • Hypoglycemia due to sulfonylurea (glipizide): Although less likely given the context of acidosis, sulfonylureas can cause hypoglycemia, which might present with dizziness, nausea, and vomiting. However, hypoglycemia typically does not cause acidosis.
  • Gastrointestinal side effects from GLP-1 receptor agonists (Byetta): These medications can cause nausea, vomiting, and diarrhea, potentially leading to dehydration and hypotension. However, they are less commonly associated with severe acidosis.

• Do Not Miss Diagnoses

  • Lactic acidosis due to metformin (not listed but commonly used in diabetes management): Although metformin is not among the options provided, it's crucial to consider lactic acidosis in any diabetic patient presenting with acidosis, as it can be fatal if not promptly addressed.
  • Septic shock: The patient's hypotension and tachycardia could also be indicative of septic shock, especially if there's an underlying infection. This condition requires immediate recognition and treatment.

• Rare Diagnoses

  • Pancreatitis: Certain diabetes medications, including GLP-1 receptor agonists, have been associated with an increased risk of pancreatitis, which could present with nausea, vomiting, and abdominal pain. However, pancreatitis would not typically cause the degree of acidosis seen in this patient without other significant symptoms.
  • Other medication-induced acidosis: While less common, other medications or their combinations could potentially induce a state of acidosis, though this would be rare and more specific to the individual's medication regimen and health status.