Nikhil Shankar*, Prathap Thulasiram R, Sanath Manjunatha, Shaikh Mohammad Aslam S, Ashwin Kulkarni and Mohammad Suhail K

Department of General Medicine, M.S Ramaiah Medical College and Hospitals, Bengaluru, Karnataka, India

*Corresponding Author: Nikhil Shankar, Department of General Medicine, M.S Ramaiah Medical College and Hospitals, Bengaluru, Karnataka, India.

Received: March 06, 2025; Published: March 20, 2025

Abstract

Altered mentation is a frequent but challenging clinical presentation with causes comprising infections, trauma, stroke, toxins, dyshomeostasis and very rarely, autoimmune encephalitis (AIE). AIE is characterized by neuropsychiatric symptoms and antibodies against several neural proteins; one such protein being contactin-associated protein-like 2 (CASPR2).
Here, we present one such case of a 50-year-old hypertensive male presenting with worsening mental haziness since three months, difficulty walking and burning sensation of feet since one month and decreased responsiveness since 20 days. Prior evaluation at a private facility was inconclusive and psychiatric medications were initiated but to no avail. Initial assessment at current institution showed elevated blood pressure, incoherent speech and prosopagnosia. The patient was conscious, agitated and disoriented, limiting further neurological assessment. Lab investigations showed neutrophilic leucocytosis, elevated C-reactive protein levels, hypouricemia and hypotonic hyponatremia, suggestive of SIADH. MRI of the brain revealed diffuse cerebral atrophy. EEG reported diffuse slowing of cortical activity. Pathological and microbiological analysis of CSF was unremarkable.
Treatment for SIADH as per protocol proved futile. Further investigation into autoimmune causes established a diagnosis of CASPR2-positive autoimmune encephalitis. After treatment with IV immunoglobulins as per protocol, the patient significantly improved and upon follow-up, regained independence in daily activities (mRS-2).
AIE, though rare, should be considered in cases of unexplained encephalopathy. Quick and precise management are key to preventing diagnostic delays and reducing long-term effects.

 Keywords: AIE; CASPR2; VGKC; IV Immunglobulins

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Citation

Citation: Nikhil Shankar., et al. “An Enigmatic Case of Altered Sensorium". Acta Scientific Neurology 8.4 (2025): 21-27.

Copyright

Copyright: © 2025 Nikhil Shankar., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.