What are the differential diagnoses for fatigue?

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Differential Diagnosis for Fatigue

The differential diagnosis for fatigue is extensive and can be categorized into several groups.

  • Single most likely diagnosis:
    • Anemia: This is often considered due to its high prevalence and the fact that fatigue is a common presenting symptom. Anemia can result from various causes, including iron deficiency, vitamin B12 deficiency, or chronic diseases.
  • Other Likely diagnoses:
    • Hypothyroidism: A condition where the thyroid gland doesn't produce enough thyroid hormones, leading to fatigue among other symptoms.
    • Diabetes: Both type 1 and type 2 diabetes can cause fatigue due to high blood sugar levels, which can lead to feelings of tiredness.
    • Chronic Fatigue Syndrome: Also known as myalgic encephalomyelitis, this condition is characterized by extreme fatigue that cannot be explained by any underlying medical condition.
    • Depression: Fatigue is a common symptom of depression, which can also include feelings of sadness, hopelessness, and a lack of interest in activities.
    • Sleep Apnea: A condition where breathing stops and starts during sleep, leading to poor sleep quality and daytime fatigue.
  • Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
    • Addison's Disease: A rare disorder of the adrenal glands where not enough cortisol and aldosterone are produced, leading to fatigue among other severe symptoms.
    • Heart Failure: Fatigue can be an early symptom of heart failure, where the heart is unable to pump enough blood to meet the body's needs.
    • Lymphoma: A type of cancer that affects the immune system and can cause fatigue, among other symptoms like weight loss and night sweats.
    • Chronic Obstructive Pulmonary Disease (COPD): A group of lung diseases that block airflow and make it difficult to breathe, leading to fatigue.
  • Rare diagnoses:
    • Mitochondrial Myopathies: A group of disorders that affect the mitochondria, leading to muscle weakness and fatigue.
    • Pernicious Anemia: A rare condition where the body is unable to absorb vitamin B12, leading to anemia and fatigue.
    • Wilson's Disease: A rare genetic disorder that causes copper to accumulate in the body, leading to liver, neurological, and psychiatric symptoms, including fatigue.

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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