Chloroquine and hydroxychloroquine (HCQ) are commonly used antimalarial agents as the treatment for a wide range of autoimmune disorders including dermatological, rheumatoid, and connective tissue diseases. These amphiphilic drugs can cause toxic myopathy in in patients which are commonly characterized as reversible proximal muscle weakness, dysphagia and dyspnea. Herein, we report a case of a patient on HCQ, who suffered from toxic myopathy presenting as proximal muscle weakness and dysarthria, which was fully recovered after the cessation.

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a neuroinflammatory disease mediated by autoantibodies against the NMDAR, typically presenting with psychiatric symptoms, cognitive dysfunction, and motor dysfunction. These neuropsychiatric symptoms may be mimicked by drug abuse, and the development of anti-NMDAR encephalitis may be triggered by certain substance use. Here we report a case of anti-NMDAR encephalitis who developed neuropsychiatric symptoms after illicit substance use, the first report in Korea.

Anti-3-hydroxy-3-methylglutaryl coenzyme A reductase (anti-HMGCR) antibody related immune-mediated necrotizing myopathy (IMNM) are usually associated with statin use. The disease has features of persistent muscle weakness and creatine kinase (CK) elevation after statin discontinuation. This report describes a 65-year-old female taking atorvastatin, presenting with both proximal lower extremity weakness. IMNM feature were detected on muscle biopsy and high anti-HMGCR autoantibody titer on enzyme-linked immunosorbent assay (ELISA). This patient was treated with corticosteroid. Muscle weakness and CK are improved after immunosuppressive therapy.

Palinacousis is a rare auditory phenomenon characterized by the persistence of sounds beyond their actual duration. It has been associated with various brain conditions such as stroke, tumor, and seizure in the temporoparietal lobe. We present a case report of a 43-yearold man who developed palinacousis following cerebral venous thrombosis and seizure with lesions including the left auditory cortex. This case highlights the intriguing relationship between cerebral venous infarction, seizure, and the development of palinacousis in specific brain regions.