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Differential Diagnosis for 15 yo f with Fatigue

  • Single most likely diagnosis
    • Viral infection (e.g., upper respiratory tract infection): This is a common cause of fatigue in adolescents, especially given the non-specific nature of the symptoms and the short duration.
  • Other Likely diagnoses
    • Anemia: Could be due to various reasons such as iron deficiency, which is common in adolescent females, especially if they have started menstruating.
    • Hypothyroidism: Although less common, it's a possible cause of fatigue and should be considered, especially if there are other symptoms like weight gain or cold intolerance.
    • Depression: Fatigue can be a presenting symptom of depression, which is a significant concern in adolescents.
    • Sleep disorders (e.g., insomnia, sleep apnea): Poor sleep quality or quantity can lead to fatigue.
  • Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
    • Diabetes mellitus: Both type 1 and type 2 diabetes can present with fatigue among other symptoms like polyuria and polydipsia.
    • Infectious mononucleosis (mono): Caused by Epstein-Barr virus, it can lead to significant fatigue and has a risk of splenic rupture.
    • Lyme disease: If the patient has been exposed to ticks, Lyme disease could be a consideration, as it can cause fatigue along with other symptoms like a distinctive rash and joint pain.
    • Leukemia or lymphoma: Although rare, these cancers can present with non-specific symptoms like fatigue and would be critical to diagnose early.
  • Rare diagnoses
    • Chronic fatigue syndrome (myalgic encephalomyelitis): A condition characterized by extreme fatigue that cannot be explained by any underlying medical condition.
    • Mitochondrial diseases: A group of disorders caused by dysfunctional mitochondria, which can lead to fatigue among a wide range of other symptoms.
    • Adrenal insufficiency: A condition where the adrenal glands do not produce adequate amounts of hormones, leading to fatigue and potentially life-threatening complications if not treated.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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