Differential Diagnosis for HHS (Hyperosmolar Hyperglycemic State)
- Single most likely diagnosis:
- Diabetes Mellitus Type 2: This is the most common underlying condition leading to HHS, especially in older adults. The presence of hyperglycemia, dehydration, and altered mental status in a patient with a history of type 2 diabetes makes this the most likely diagnosis.
- Other Likely diagnoses:
- Diabetes Mellitus Type 1: Although less common than type 2, type 1 diabetes can also lead to HHS, particularly if insulin therapy is inadequate or if the patient has an infection or other stressor.
- Infections (e.g., pneumonia, urinary tract infections): Infections can precipitate HHS in patients with diabetes by increasing insulin resistance and glucose production.
- Medication-induced hyperglycemia (e.g., steroids, certain antipsychotics): Certain medications can cause hyperglycemia as a side effect, potentially leading to HHS in susceptible individuals.
- Do Not Miss diagnoses:
- Septic shock: The clinical presentation of HHS can overlap with septic shock, including hypotension, altered mental status, and signs of organ dysfunction. Missing septic shock could be fatal.
- Stroke or intracranial hemorrhage: Altered mental status in HHS could also be due to a stroke or intracranial hemorrhage, which requires immediate intervention.
- Acute coronary syndrome: Chest pain or electrocardiogram changes in a patient with HHS could indicate an acute coronary syndrome, which is a medical emergency.
- Rare diagnoses:
- Pancreatic cancer: Although rare, pancreatic cancer can cause diabetes and potentially lead to HHS, especially if it involves the islet cells.
- Endocrine disorders (e.g., Cushing's syndrome, pheochromocytoma): Certain endocrine disorders can cause hyperglycemia and potentially lead to HHS.
- Genetic disorders affecting insulin secretion or action: Rare genetic disorders, such as maturity-onset diabetes of the young (MODY), can affect insulin secretion and increase the risk of HHS.