Differential Diagnosis for 18 yo with POTS, Refractory Presyncope, and Full Body Aches

• Single Most Likely Diagnosis

  • Postural Orthostatic Tachycardia Syndrome (POTS) with associated symptoms: This diagnosis is the most likely because the patient's primary complaint of POTS is already stated, and refractory presyncope and full body aches can be associated symptoms of POTS. POTS is characterized by a rapid increase in heart rate and other symptoms that occur upon standing, which can include presyncope and widespread pain due to autonomic nervous system dysfunction.

• Other Likely Diagnoses

  • Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): This condition often presents with persistent and profound fatigue, muscle pain, and other symptoms that could align with the patient's complaints. The full body aches and presyncope could be part of the symptom complex of ME/CFS.
  • Ehlers-Danlos Syndrome (EDS): EDS, particularly the hypermobile type, can present with joint pain, fatigue, and autonomic dysfunction, which might include POTS and presyncope. Full body aches could be related to the musculoskeletal manifestations of EDS.
  • Mast Cell Activation Syndrome (MCAS): MCAS can cause a wide range of symptoms including orthostatic intolerance (similar to POTS), musculoskeletal pain, and systemic symptoms that could fit the patient's presentation.

• Do Not Miss Diagnoses

  • Cardiac Arrhythmias or Structural Heart Disease: Conditions such as long QT syndrome, hypertrophic cardiomyopathy, or other arrhythmias could cause presyncope and potentially full body aches due to decreased cardiac output. These conditions are critical to diagnose due to their potential for sudden cardiac death.
  • Neurological Disorders (e.g., Multiple Sclerosis, Neuromyelitis Optica): Although less likely, certain neurological conditions could present with a combination of symptoms including presyncope (due to autonomic dysfunction) and widespread pain.
  • Autoimmune Disorders (e.g., Lupus, Rheumatoid Arthritis): Systemic autoimmune diseases can cause a wide range of symptoms including joint pain, fatigue, and potentially autonomic dysfunction leading to presyncope.

• Rare Diagnoses

  • Mitochondrial Myopathies: These are a group of disorders caused by mitochondrial dysfunction and can lead to muscle weakness, fatigue, and potentially autonomic dysfunction.
  • Dysautonomia due to Rare Neurological Conditions (e.g., Familial Dysautonomia): These conditions are characterized by widespread autonomic dysfunction and could potentially present with the symptoms described.
  • Porphyrias: A group of rare disorders that can cause acute intermittent porphyria, leading to abdominal pain, neurological symptoms, and potentially autonomic dysfunction resulting in presyncope and widespread pain.