Advanced Medical Life Support (AMLS)

What is the most probable working diagnosis for an obese patient with extreme thirst and lethargy?

1. Thyroid storm

2. Cushing's syndrome

3. Diabetic ketoacidosis

4. Hyperosmolar hyperglycemic nonketotic coma

The correct answer is: Hyperosmolar hyperglycemic nonketotic coma

The most probable working diagnosis in this scenario is hyperosmolar hyperglycemic nonketotic coma. This condition is characterized by severe hyperglycemia and significant dehydration, both of which can result from poor diabetes management, especially in obese individuals. Extreme thirst, or polydipsia, and lethargy are common symptoms due to the body's attempt to compensate for hyperglycemia by drawing water out of cells, leading to dehydration. In hyperosmolar hyperglycemic nonketotic coma, the patient typically presents with significantly elevated blood glucose levels without the presence of significant ketosis, which distinguishes it from diabetic ketoacidosis. The lethargy can result from both dehydration and the effects of hyperglycemia on the central nervous system, reflecting the state of severe metabolic disturbance. Other conditions listed, like thyroid storm and Cushing's syndrome, do present with some overlapping symptoms such as lethargy, but they do not explain the extreme thirst and dehydration in the context of obesity as well as hyperosmolar hyperglycemic nonketotic coma does. Diabetic ketoacidosis also features extreme thirst and lethargy but is typically associated with acidosis and ketosis, which are less likely in this scenario based on the presentation described. Therefore, given the