Can mustard gas induce late onset polyneuropathy?

Background: Mustard gas, lethal in high doses, affects multiple organs such as skin, eye and respiratory system. We studied the development of late onset mustardinduced polyneuropathy among chemically wounded Iranian veterans. Methods: In this descriptive study, 100 chemically wounded Iranian veterans with severe eye involvement were examined for any signs and symptoms of polyneuropathy by an internist. 20 patients were suspected to have neurological symptoms or signs. These patients were examined by a neurologist again. 13 showed abnormal neurological symptoms. Electrodiagnostic exams were performed for this group by another physician. Results: 13 veterans had abnormal neurological exam results with prominent sensory signs and symptoms in almost all of them. Brisk deep tendon reflexes were found in 3 cases. Electrodiagnostic studies were compatible with axonal type distal sensory polyneuropathy in 6 subjects. Conclusion: To the best of our knowledge, this is the first report of late onset polyneuropathy among chemically-wounded victims who were exposed to mustard gas. The pathophysiology of this form of neuropathy is still unknown. Unlike most toxic neuropathies, obvious clinical signs and symptoms appeared several years after exposure. No specific treatment for polyneuropathy due to chemical weapons exposure has been described to date.