Differential Diagnosis
- Single most likely diagnosis
- Cubital Tunnel Syndrome or Ulnar Neuropathy: The patient's symptoms of feeling tiny vibrations in her forearm and mild pain in the arm, especially when typing, could be indicative of nerve compression or irritation. The history of wearing an Apple Watch tightly on the same wrist for 5 years, resulting in a permanent dent, suggests chronic pressure on the area, which could lead to nerve damage or compression, particularly of the ulnar nerve.
- Other Likely diagnoses
- Radial Neuropathy: This condition could also explain the symptoms of abnormal sensations and pain in the arm, especially if the radial nerve is compressed or irritated, possibly due to the tight watch or repetitive strain from typing.
- Thoracic Outlet Syndrome: The symptoms of arm pain and abnormal sensations could be related to compression of the nerves and/or blood vessels that pass through the thoracic outlet, potentially exacerbated by the patient's history of wearing a tight watch or previous shingles infection affecting nerve pathways.
- Peripheral Neuropathy: Given the patient's history of type 1 diabetes, peripheral neuropathy is a possible diagnosis. Although the symptoms are localized to one arm, diabetic neuropathy can sometimes present asymmetrically or focally, especially if there's been nerve damage from other causes.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Lymphoma or Other Malignancies: Although the patient's melanoma was cured with surgery, there's always a concern for recurrence or development of a new malignancy, especially in someone with a history of cancer. Lymphoma, in particular, can cause neuropathic symptoms due to nerve infiltration.
- Infectious or Inflammatory Causes (e.g., Lyme Disease, Sarcoidosis): These conditions can cause neuropathy and should be considered, especially given the patient's history of shingles, which indicates a potential vulnerability to viral reactivations or other infections.
- Rare diagnoses
- Tumor or Cyst Compressing Nerves: A rare but possible cause of the patient's symptoms could be a benign or malignant tumor, or a cyst, compressing the nerves in the arm.
- Vitamin Deficiency (e.g., Vitamin B12 Deficiency): Although less likely given the patient's other medical history, a vitamin deficiency could potentially cause neuropathic symptoms and should be considered if other diagnoses are ruled out.