Association of Mycoplasma Pneumoniae with Anti NMDA Receptor Autoimmune Encephalitis in a Female Child: A Case Report

ABSTRACT

A 6 year old female child presented with movement disorder, cognition impairment, insomnia and restlessness. She was diagnosed with NMDA receptor autoimmune encephalitis triggered by Mycoplasma pneumoniae and was treated successfully with high dose steroids, Intravenous immunoglobulin and Clarithromycin. A 6 year old Female child of Indian origin presented with visual hallucinations, intermittent jerky movements of left leg and left arm, agitation, screaming episodes and insomnia. On examination she had cognition impairment with truncal ataxia. MRI Brain was Normal. EEG showed epileptiform activity over right hemisphere. Mycoplasma antibody titre was strongly seropositive .Serum and CSF NMDA Receptor antibody was positive. MRI STIR was negative. After appropriate investigations, she was diagnosed with NMDA Receptor autoimmune encephalitis triggered by Mycoplasma pneumoniae and was treated successfully with high dose steroids, Intravenous immunoglobulin and Clarithromycin. NMDA Receptor encephalitis is the most common cause of autoimmune encephalitis in children. 6% to 50% of patients with anti-NMDAR encephalitis have been found to have an associated underlying tumor. Mycoplasma pneumoniae are the main presumed infectious pathogens associated with majority of the autoimmune encephalitis. It is suggested that early onset encephalitis is a direct type extrapulmonary manifestation involving cytokines and late onset encephalitis is of the indirect type involving autoimmunity.Mycoplasma infection affecting children can lead to neurological complications like autoimmune encephalitis. Further studies in this area can help to lighten the etiology of autoimmune disorders.