Asymmetrical Brachial Plexus Involvement with Greater Auricular Nerve Involvement in Borderline Tuberculoid Leprosy: An Electrophysiological and Radiological Correlation

Abstract Leprosy, caused by Mycobacterium leprae, is known for mainly affecting the peripheral nerves. But in recent years, there is growing recognition that it can also involve the central nervous system, including the spinal cord and the brachial plexus. This broader understanding of nerve involvement highlights the importance of newer diagnostic tools like nerve conduction studies, high-resolution ultrasonography, and magnetic resonance imaging, which can help detect and assess these deeper structures and more complex manifestations. We present an intriguing case of a 27-year-old male diagnosed with borderline tuberculoid leprosy based on histopathology, who was found to have brachial plexopathy on nerve conduction studies and magnetic resonance imaging, along with involvement of the greater auricular nerve as revealed by high-resolution ultrasonography.