Inspiratory laryngeal stridor as the main feature of progressive encephalomyelitis with rigidity and myoclonus: a case report and literature review

Abstract

Background Progressive encephalomyelitis with rigidity and myoclonus (PERM) is an acute, potentially life-threatening, yet curable neuro-immunological disease characterized by spasms, muscular rigidity, and brainstem and autonomic dysfunction. The clinical features of glycine receptor (GlyR) antibody-positive PERM may be overlooked, particularly with some unusual symptoms. Case presentation A 52-year-old man was admitted to the hospital for evaluation of tension headache for 20 days and mild dysarthria. These symptoms were followed by panic, profuse sweating, severe dysarthria, dizziness, unsteady gait, and paroxysmal muscle spasms. Brain magnetic resonance imaging and cerebrospinal fluid analysis were normal. The patient’s condition steadily deteriorated. He repeatedly presented with rigidity, panic attacks, severe anxiety, paroxysmal inspiratory laryngeal stridor, cyanosis of the lips, and intractable epilepsy. Electromyography showed multiple myoclonic seizures, a single generalized tonic-clonic seizure, and a single generalized tonic seizure. Screening for autoimmune encephalitis antibodies revealed anti-GlyR antibodies in his cerebrospinal fluid. Immunomodulatory pulse therapy with steroids and immunoglobulin resulted in expeditious improvement of the symptoms within 2 weeks, and a follow-up at 5 weeks showed consistent clinical improvement. Conclusion Our case highlights that inspiratory laryngeal stridor is an important symptom of PERM. Our observation widens the spectrum of the clinical presentation of anti-GlyR antibody-positive PERM, where early identification is a key to improving prognosis.

Clinical features in antiglycine receptor antibody-related disease: a case report and update literature review

“…Anti-GlyR antibody related-disease may accompany tumorigenesis (22). In addition to thymoma, lymphoma, breast cancer, lung cancer, melanoma, and seminoma reported in previous studies, bladder cancer, tongue cancer, carcinoma of the urinary bladder, uterine cervix neoplasia, tongue cancer, thyroid papillary carcinoma, and ovarian teratoma may also occur (29,31,32,(41)(42)(43)(44)(45)(46). MRI and EEG are normal in most patients, and those with epilepsy as the clinical manifestation have a high possibility of abnormal results.…”

Case report: Varicella-zoster virus infection triggering progressive encephalomyelitis with rigidity and myoclonus

“…The pathogenesis of PERM is unclear, but it is currently considered to be a multiple-antibody-mediated autoimmune disease. Glutamate decarboxylase (GAD) and GlyR antibodies are found in most patients with PERM ( 4 ). Amphoteric proteins, dipeptidyl peptidase-like protein 6 antibodies, voltage-gated potassium channel complexes, and leucine-rich glioma-inactivating protein-1 have also been reported to be present in patients with PERM ( 1 , 5 – 7 ).…”