LAUSR

Acute encephalitis is a life-threatening neurological illness that presents as a rapidly progressive encephalopathy due to inflammation of the brain.1 In the recent past, in addition to infectious causes, various autoantibody-mediated encephalitis has been identified. There are two types of immune-mediated encephalitis, namely, paraneoplastic encephalopathy syndromes related to cancers and antibody perturbing neuronal surface proteins or antigens of synapses.2 Autoimmune encephalitis has distinct categories such as anti-N-methyl-D-aspartate receptor (anti-NMDAR), leucine-rich glioma-inactivated protein 1, and contactin-associated protein-2.3 Autoimmune encephalitis is a specific syndrome with characteristic clinical features. Anti-NMDAR encephalitis is a subtype of autoimmune encephalitis occurring due to autoantibodies targeting NMDARs either due to ovarian teratoma or preceding viral infections acting as triggers.4 Nonhepatic hyperammonemia occurs due to disorders not involving hepatic pathways directly. Inadequate dietary intake in intensive care unit (ICU) patients can precipitate hyperammonemia encephalopathy, which can exacerbate the ill effects of preexisting illness.5 In this case illustration, we presented a patient of anti-NMDAR encephalitis treated with sequential immunomodulatory drugs. The case had prolonged hyperammonemia contributing to a longer duration of illness, and corrective measures led to complete recovery. We emphasized that ammonia levels should be assessed in treating patients with autoimmune encephalitis. Case History