Case Details
A 45-year-old woman presents with a four-month history of progressive fatigue, dizziness, and difficulty walking. She also reports burning sensations in her feet, intermittent confusion, and difficulty concentrating.
Her medical history includes chronic gastritis, long-term use of proton pump inhibitors (PPIs), and an unspecified autoimmune condition. She follows a vegetarian diet, avoiding meat and dairy.
Examination Findings
- Neurological: Bilateral lower limb weakness, loss of vibration and proprioception in the feet, hyperreflexia with absent Achilles reflex, and a positive Babinski sign.
- Oral: Mild atrophic glossitis.
- Skin: Hyperpigmentation over the dorsal hands and knuckles.
Initial Laboratory Findings
- Hemoglobin: 9.2 g/dL (Low)
- Mean Corpuscular Volume (MCV): 118 fL (High)
- Reticulocyte Count: Low
- Serum Ferritin: Normal
- TSH & Free T4: Normal
- Serum Homocysteine: Elevated
- Serum Methylmalonic Acid (MMA): Elevated
Image Analysis Challenge
The attached image highlights key clinical and laboratory findings. Carefully analyze the visual elements and consider their significance in forming a diagnosis.
Your Challenge
- What is the most likely diagnosis?
- What additional history questions would you ask?
- What further laboratory investigations should be performed to confirm the diagnosis?
- How do you explain the hyperpigmentation?
The full case discussion can be found here.
