Differential Diagnosis for 39 YOF with Episode of Fainting

• Single most likely diagnosis
  • Hypoglycemia: Although the POC glucose is 5.4 mmol/L, which is within the normal range, the patient's history of bariatric surgery and significant weight loss could lead to hypoglycemic episodes due to changes in glucose metabolism and insulin sensitivity. The symptoms of shakiness and weakness after fainting could be indicative of a hypoglycemic episode that may have occurred prior to the glucose measurement.
• Other Likely diagnoses
  • Dehydration: Given the patient's recent weight loss and history of bariatric surgery, dehydration could be a contributing factor to the fainting episode, especially if the patient is not adequately replenishing fluids.
  • Orthostatic hypotension: The patient's significant weight loss and potential for dehydration could lead to orthostatic hypotension, causing fainting when standing up.
  • Anxiety or panic attack: The symptoms of shakiness and weakness could also be indicative of an anxiety or panic attack, which may have triggered the fainting episode.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Cardiac arrhythmia: Although the patient's BP is within a relatively normal range, it's crucial to consider cardiac causes of syncope, including arrhythmias, which could be life-threatening if not promptly diagnosed and treated.
  • Pulmonary embolism: Given the patient's history of recent significant weight loss and potential for increased risk of thromboembolic events, pulmonary embolism should be considered as a potential cause of fainting.
  • Stroke or transient ischemic attack (TIA): Although less likely in a young patient, stroke or TIA should always be considered in the differential diagnosis of fainting, especially if there are any focal neurological deficits.
• Rare diagnoses
  • Pheochromocytoma: A rare tumor of the adrenal gland that could cause episodes of fainting, hypertension, and other symptoms due to excessive catecholamine release.
  • Autonomic dysfunction: Certain conditions affecting the autonomic nervous system, such as dysautonomia, could lead to fainting episodes due to abnormal blood pressure regulation.
  • Endocrine disorders: Other endocrine disorders, such as adrenal insufficiency or thyroid storm, could potentially cause fainting episodes, although these would be less likely given the patient's presentation and history.