How to manage a 40-year-old female with Down syndrome, history of hypothyroidism, and type 2 diabetes mellitus (DM 2) who presents to urgent care after a loss of consciousness episode followed by jerky movements, with a history of similar episodes and current asymmetry, but a normal neurological examination?

Differential Diagnosis for 40-year-old Female with Down Syndrome

Single Most Likely Diagnosis

• Seizure Disorder: Given the history of loss of consciousness followed by jerky movements, which is suggestive of seizure activity, and the fact that this is a recurrent episode, a seizure disorder is the most likely diagnosis. Individuals with Down syndrome are at an increased risk of developing seizure disorders.

Other Likely Diagnoses

• Hypoglycemia: As a patient with diabetes mellitus type 2, hypoglycemia could lead to loss of consciousness and jerky movements, especially if the patient has been taking diabetes medications.
• Thyroid Storm: Although less common, given her history of hypothyroidism, if she has been non-compliant with her medication or has developed hyperthyroidism, thyroid storm could present with altered mental status and seizures.
• Stroke or Transient Ischemic Attack (TIA): The asymmetry noted could suggest a vascular event, although the normal neurological exam makes this less likely. However, in patients with Down syndrome, the risk of early onset vascular diseases might be higher.

Do Not Miss Diagnoses

• Meningitis or Encephalitis: Infections of the central nervous system can present with altered mental status and seizures. Although less likely, missing these diagnoses could be fatal.
• Status Epilepticus: If the patient had a prolonged seizure or recurrent seizures without full recovery in between, this is a medical emergency requiring immediate intervention.
• Cardiac Arrhythmias: Sudden loss of consciousness could be due to a cardiac cause, especially in a patient with potential metabolic derangements.

Rare Diagnoses

• Hashimoto's Encephalopathy: A rare condition associated with autoimmune thyroiditis, which can cause seizures, altered mental status, and stroke-like symptoms.
• Metabolic Disorders: Other metabolic disorders, such as those affecting electrolyte balance (e.g., hyponatremia), could lead to seizures and loss of consciousness, although these would be less common in this context.