Differential Diagnosis

The patient's symptoms of body pain, dizziness, arthralgia, missed periods, nausea, vertigo, and fatigue can be approached by categorizing potential diagnoses into the following groups:

• Single Most Likely Diagnosis

  • Pregnancy: This is the most likely diagnosis given the combination of missed periods, nausea, and the other symptoms which can be associated with early pregnancy, including dizziness, fatigue, and body pain due to hormonal changes.

• Other Likely Diagnoses

  • Viral Infections (e.g., Flu): Could explain body pain, fatigue, dizziness, and nausea. The recent onset of symptoms could suggest an acute viral infection.
  • Anxiety or Panic Disorder: Might cause dizziness, nausea, fatigue, and body pain due to heightened stress and anxiety responses.
  • Hypothyroidism: Can lead to fatigue, body pain, and menstrual irregularities, including missed periods.

• Do Not Miss Diagnoses

  • Ectopic Pregnancy: Although less likely, it's crucial to rule out ectopic pregnancy, especially with missed periods and abdominal pain, as it is life-threatening.
  • Multiple Sclerosis: An episode of vertigo, along with other neurological symptoms, could be a presentation of MS, which requires prompt diagnosis and treatment.
  • Lupus or Other Autoimmune Disorders: These conditions can cause arthralgia, body pain, and systemic symptoms, including fatigue and dizziness, and are important not to miss due to their potential for serious complications.

• Rare Diagnoses

  • Chronic Fatigue Syndrome: Characterized by profound fatigue that is not improved by rest, it could be considered if other diagnoses are ruled out and fatigue persists.
  • Fibromyalgia: A condition causing widespread musculoskeletal pain accompanied by fatigue, sleep, memory, and mood issues, which might be a consideration in the absence of other clear diagnoses.
  • Wilson's Disease: A rare genetic disorder that leads to copper accumulation in the body, potentially causing fatigue, dizziness, and other systemic symptoms, though it would be an uncommon presentation.

Each of these diagnoses should be considered and evaluated based on the patient's full medical history, physical examination, and appropriate diagnostic tests to determine the underlying cause of their symptoms.