Differential Diagnosis for Confusion and Awkward Speech in a 76-year-old Woman
- Single most likely diagnosis:
- Receptive aphasia: The patient's speech is voluminous and fluent but meaningless, and she is unable to name objects appropriately, giving them nonsensical names. This pattern is characteristic of receptive aphasia, also known as Wernicke's aphasia, where patients have difficulty understanding spoken language and their own speech is often long, rambling, and neologistic.
- Other Likely diagnoses:
- Global aphasia: Although less likely given the fluent nature of her speech, global aphasia could be considered if the patient's comprehension and expression are both significantly impaired. However, the description leans more towards receptive aphasia due to the fluent but nonsensical speech.
- Conductive aphasia: This type of aphasia involves difficulty with repetition and finding the right words, but the patient's speech is often described as fluent. However, the primary issue in conductive aphasia is the struggle to repeat words and phrases, which is not the primary complaint here.
- Do Not Miss diagnoses:
- Stroke or Transient Ischemic Attack (TIA): Given the patient's history of paroxysmal atrial fibrillation and recent cessation of warfarin, there is a high risk for thromboembolic events. The sudden onset of confusion and speech difficulties could be indicative of a stroke or TIA, even with a normal CT scan, as early changes might not be visible.
- Seizure: Post-ictal confusion and aphasia could occur after a seizure, which might not have been witnessed. The recent dental procedure and cessation of anticoagulation could potentially contribute to a seizure through various mechanisms, including stress or embolic events.
- Rare diagnoses:
- Delirium due to other causes: While the patient's presentation is primarily suggestive of a focal neurological deficit (aphasia), delirium from other causes (infection, metabolic disturbances, medication side effects) should be considered, especially given her recent dental procedure and change in anticoagulation status.
- Psychogenic causes: Although less likely, psychogenic causes of aphasia or pseudo-aphasic symptoms can occur, especially in the context of significant psychological stress. However, the acute onset and specific nature of the language difficulties make this a less probable diagnosis.