Differential Diagnosis

The patient's presentation with diarrhea, vomiting, and elevated blood sugar after eating pizza, along with tongue swelling treated with epinephrine and decadron, suggests several potential diagnoses. Here is a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Diabetic ketoacidosis (DKA) with a possible allergic reaction to a component of the pizza: The patient's elevated blood sugar (399), beta-hydroxybutyrate (5.5), and lactic acid (3.1) levels, along with a pH of 7.31, are indicative of DKA. The tongue swelling treated with epinephrine and decadron suggests an allergic reaction, possibly to a food component in the pizza.

• Other Likely Diagnoses

  • Food poisoning: The onset of symptoms after eating pizza could suggest food poisoning, which might also explain the gastrointestinal symptoms.
  • Allergic reaction: The tongue swelling and the need for epinephrine and decadron indicate a significant allergic reaction, which could be related to a food allergy or another component of the meal.
  • Hyperglycemic hyperosmolar nonketotic syndrome (HHNS): Although the beta-hydroxybutyrate level is elevated, suggesting DKA, the presence of significant hyperglycemia and symptoms like vomiting could also point towards HHNS, especially if the ketone levels were not as high as expected.

• Do Not Miss Diagnoses

  • Anaphylaxis: Given the patient's response to epinephrine and decadron for tongue swelling, anaphylaxis should be considered, especially if there are other signs of severe allergic reaction.
  • Infection: An underlying infection could precipitate DKA or HHNS in a diabetic patient and would require prompt identification and treatment.
  • Acute pancreatitis: Abdominal pain, vomiting, and elevated pancreatic enzymes could suggest pancreatitis, which is a serious condition requiring immediate attention.

• Rare Diagnoses

  • Latent autoimmune diabetes in adults (LADA) with an acute presentation: Although less common, LADA could present with DKA, especially if the patient has not been previously diagnosed with diabetes.
  • Other endocrinopathies: Rarely, other endocrine disorders could present with similar symptoms, such as adrenal insufficiency or pheochromocytoma, though these would be less likely given the information provided.