Differential Diagnosis for a 46-year-old Male with Left Arm Pain and Other Symptoms

The patient presents with left arm pain, a sensation of something moving inside the arm, nausea, dizziness, and a history of diabetes, hypertension, and gastroparesis. The differential diagnosis can be categorized as follows:

• Single Most Likely Diagnosis

  • Peripheral Neuropathy: Given the patient's history of diabetes, the sensation of something moving inside the arm could be indicative of peripheral neuropathy, a common complication of diabetes that affects nerve function. The pain and unusual sensations in the arm could be related to nerve damage.

• Other Likely Diagnoses

  • Musculoskeletal Injury: The left arm pain could be due to a musculoskeletal injury, such as a strain or sprain, which might not be directly related to his chronic conditions but could be exacerbated by them.
  • Gastroparesis-related Symptoms: Although the patient does not have vomiting, his nausea could be related to gastroparesis, especially if he has been experiencing delayed gastric emptying, which might also contribute to dizziness due to electrolyte imbalances or dehydration.
  • Hypertension-related Complications: Uncontrolled hypertension can lead to various complications, including vascular diseases that might cause arm pain, though this would be less common and might be accompanied by other symptoms.

• Do Not Miss Diagnoses

  • Acute Coronary Syndrome (ACS): Although the patient denies chest pain, ACS can sometimes present atypically, especially in diabetic patients, with arm pain being a possible symptom. It is crucial to consider this diagnosis due to its high mortality if missed.
  • Stroke or Transient Ischemic Attack (TIA): The dizziness and arm symptoms could potentially indicate a stroke or TIA, particularly if there are accompanying neurological deficits, which would need immediate attention.
  • Deep Vein Thrombosis (DVT): DVT can cause arm pain and swelling, and while less common than in the legs, it is a critical diagnosis not to miss due to the risk of pulmonary embolism.

• Rare Diagnoses

  • Complex Regional Pain Syndrome (CRPS): This condition can cause severe, burning pain in the arms or legs, usually after an injury or trauma. The sensation of something moving inside the arm might be consistent with CRPS, though it is less common.
  • Thoracic Outlet Syndrome: This involves compression, injury, or irritation of the nerves and/or blood vessels (arteries and veins) in the thoracic outlet area, which can cause pain in the shoulders and neck and sometimes down the arm.

Workup in the Emergency Department

• Vital Signs: Monitor blood pressure, heart rate, respiratory rate, oxygen saturation, and blood glucose levels.
• Electrocardiogram (ECG): To evaluate for cardiac causes of the symptoms, including ACS.
• Imaging: Consider a chest X-ray, and depending on the suspicion of vascular or neurological causes, a CT angiogram of the chest or an MRI of the brain and neck might be necessary.
• Laboratory Tests: Complete blood count (CBC), basic metabolic panel (BMP), troponin levels to rule out cardiac injury, and coagulation studies if DVT or pulmonary embolism is suspected.
• Neurological Examination: A thorough neurological exam to assess for any deficits that might suggest a stroke or other neurological conditions.
• Vascular Examination: Assess the arms for signs of DVT or other vascular issues, such as swelling, warmth, or discoloration.