Painful neuropathy in subclinical hypothyroidism: clinical and neuropathological recovery after hormone replacement therapy

We describe a 60-year-old woman complaining of severe burning feet for 3 months. A neurological examination showed absent Achilles tendon reflexes; nerve conduction study demonstrated mild sensory neuropathy, and skin biopsy revealed a length-dependent loss of intraepidermal nerve fibres. Haematological exams demonstrated a subclinical hypothyroidism and hormone replacement therapy was started. Conversely, symptomatic treatments for neuropathic pain were withdrawn after few days because of side effects. During the following months, thyroid function recovered, and the patient experienced a progressive decrease of neuropathic pain intensity. At 6- and 12-month follow-ups, nerve conduction study and clinical examination were normal, whereas skin biopsy demonstrated a complete reinnervation of the epidermis. Subclinical hypothyroidism is a possible cause of sensory neuropathy and hormone replacement therapy can prompt nerve regeneration.