Complex Regional Pain Syndrome After Herpes Zoster Infection: An Uncommon and Underrecognized Clinical Entity

Latent varicella-zoster virus reactivation causes herpes zoster, which manifests as a dermatomal rash. Complex regional pain syndrome (CRPS) after herpes is an uncommon complication in clinical practice. CRPS has the following main components, which include pain, sensory, vasomotor, sudomotor, and motor/trophic. The most common sequelae of herpes zoster are postherpetic neuralgia, but CRPS is underrecognised. We present a case report of a 68-year-old female patient who had vesicular rash along the C7/C8 dermatome, clinically indicating a herpes zoster episode. Following this episode, she experienced pain, swelling, and functional impairment in the C7, C8 dermatome. CRPS was diagnosed on the basis of the Budapest criteria clinically. Neuropathic pain drugs, physical therapy, and supportive care are all part of a multidisciplinary strategy that gradually improves symptoms. This case highlights a rare herpes zoster infection sequelae of CRPS that remains underrecognised in clinical practice in developing countries. Post-herpetic neuralgia is a common sequela, and its progression to CRPS represents a distinct and underdiagnosed cause in patients.