Differential Diagnosis for Altered Mental Status in a 70-year-old Female
Single Most Likely Diagnosis
- Medication Side Effects or Overmedication: Given the age of the patient, polypharmacy is common, and many medications can cause altered mental status as a side effect. Elderly patients are more susceptible to the effects of medications due to decreased metabolism and excretion.
Other Likely Diagnoses
- Urinary Tract Infection (UTI): UTIs are common in elderly women and can cause altered mental status, especially if the infection has progressed to sepsis.
- Dehydration: Dehydration can lead to altered mental status, and elderly individuals may have decreased thirst sensation, making them more prone to dehydration.
- Electrolyte Imbalance: Electrolyte disturbances such as hyponatremia, hypernatremia, hypokalemia, or hyperkalemia can cause altered mental status.
- Stroke or Transient Ischemic Attack (TIA): Although not as common as other causes, stroke or TIA should be considered, especially if there are focal neurological deficits.
Do Not Miss Diagnoses
- Sepsis: Sepsis can present with altered mental status, and it is crucial to identify and treat promptly to prevent high mortality.
- Hypoglycemia: Hypoglycemia can cause altered mental status, and it is essential to check blood glucose levels, especially if the patient has diabetes.
- Hyperglycemia: Severe hyperglycemia, such as in diabetic ketoacidosis or hyperglycemic hyperosmolar nonketotic syndrome, can also cause altered mental status.
- Subdural Hematoma: A subdural hematoma can occur after a fall, which is common in elderly individuals, and can cause altered mental status.
- Carbon Monoxide Poisoning: Carbon monoxide poisoning can cause altered mental status, and it is essential to consider this diagnosis, especially if there are multiple people affected in the same household.
Rare Diagnoses
- Vitamin B12 Deficiency: Vitamin B12 deficiency can cause altered mental status, but it is less common and usually presents with other symptoms such as weakness, fatigue, and neurological deficits.
- Hashimoto's Encephalopathy: A rare condition that can cause altered mental status, seizures, and stroke-like symptoms in patients with Hashimoto's thyroiditis.
- Wernicke's Encephalopathy: A rare condition caused by thiamine deficiency, usually seen in patients with alcohol use disorder, but can also occur in other conditions such as gastrointestinal disorders or malignancies.
- Creutzfeldt-Jakob Disease: A rare, degenerative, and fatal brain disorder that can cause altered mental status, dementia, and neurological deficits.