Isolated ulnar dorsal cutaneous nerve herpes zoster reactivation.

Herpes zoster is a viral disease presenting with vesicular eruptions that are usually preceded by pain and erythema. Herpes zoster can be seen in any dermatome of the body but most commonly appears in the thoracic region. Herpes zoster virus is typically transmitted from person to person through direct contact. The virus remains dormant in the dorsal ganglion of the affected individual throughout his or her lifetime. Herpes zoster reactivation commonly occurs in elderly people due to normal age-related decline in cell-mediated immunity. Postherpetic neuralgia is the most common complication and is defined as persistent pain or dysesthesia 1 month after resolution of the herpetic rash. This article describes a healthy 51-year-old woman who experienced a burning sensation and shooting pain along the ulnar dorsal cutaneous nerve. Ten days after the onset of pain, she developed cutaneous vesicular eruption and decreased light-touch sensation. Wrist and fourth and fifth finger range of motion were painful and slightly limited. Muscle strength was normal. Nerve conduction studies indicated an ulnar dorsal cutaneous nerve lesion. She was treated with anti-inflammatory and antibiotic drugs and the use of a short-arm resting splint. At 5-month follow-up, she reported no residual pain, numbness, or weakness. Herpes zoster in the upper extremity may be mistaken for entrapment neuropathies and diseases characterized by skin eruptions; ulnar nerve zoster reactivation is rarely seen. The authors report an uncommon ulnar dorsal cutaneous nerve herpes zoster reactivation. Clinicians should be aware of this virus during patients' initial evaluation.