Differential Diagnosis

The patient's symptoms of severe fatigue, generalized body pain, lightheadedness, headaches, nausea, subjective fever, skin sensitivity, light sensitivity, dry eyes, and dry mouth can be approached by considering the following categories:

• Single most likely diagnosis

  • Fibromyalgia: This condition is characterized by widespread musculoskeletal pain, fatigue, sleep, memory, and mood issues, which align with many of the patient's symptoms. The presence of generalized body pain, fatigue, and sensitivity to light and skin could suggest fibromyalgia as a primary consideration.

• Other Likely diagnoses

  • Chronic Fatigue Syndrome (Myalgic Encephalomyelitis): Characterized by extreme fatigue that doesn't improve with rest and worsens with physical or mental activity, this condition could explain the patient's severe fatigue, headaches, and possibly the subjective fever.
  • Hypothyroidism: Although less directly linked to all symptoms, hypothyroidism can cause fatigue, body aches, dry skin, dry eyes, and dry mouth, making it a plausible diagnosis.
  • Depression: Can manifest with fatigue, body aches, headaches, and nausea, among other symptoms, and should be considered given the psychological impact of chronic symptoms.
  • Anxiety Disorders: Similar to depression, anxiety can cause a wide range of physical symptoms including fatigue, body pain, lightheadedness, and nausea.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

  • Lyme Disease: Although less common, Lyme disease can cause a wide range of symptoms including fatigue, headaches, fever, and joint pain, especially if the patient has been exposed to ticks.
  • Multiple Sclerosis: An autoimmune disease that can cause fatigue, vision problems (including sensitivity to light), and a wide range of other neurological symptoms.
  • Systemic Lupus Erythematosus (SLE): An autoimmune disease that can cause a variety of symptoms including fatigue, joint pain, fever, and sensitivity to light.
  • Sjögren's Syndrome: An autoimmune disorder that primarily affects the glands that produce tears and saliva, leading to dry eyes and dry mouth, and can also cause fatigue and joint pain.

• Rare diagnoses

  • Ehlers-Danlos Syndrome: A group of disorders that affect connective tissues supporting the skin, bones, blood vessels, and many other organs and tissues, which could explain some of the patient's symptoms like joint pain and fatigue.
  • Mitochondrial Myopathies: A group of disorders caused by mitochondrial dysfunction, leading to muscle weakness and other symptoms like fatigue.
  • Porphyrias: A group of rare disorders that can cause a variety of symptoms including abdominal pain, neurological symptoms, and sensitivity to sunlight.