Can Autoimmune Encephalitis Occur with Negative Markers? A Rare Case Report

In our case, we present a case of 27-year-old male who presented with progressively worsening altered mental status and seizures. Over the course his admission to hospital intensive care unit, laboratory testing failed find an offending agent presentation. Testing did result in diagnosis encephalitis, but underlying cause was not found. After careful exclusion bacterial, viral, other types encephalopathy, autoimmune encephalopathy diagnosed despite absence commonly used markers encephalopathy. The presentation symptoms patient led wide range differentials, high index suspicion needed throughout order obtain appropriate tests. Although might be ordered, due sensitivities specificities all tests, these objective tests do produce false negative results at times. It is times that one must weigh physical exam, clinical judgment, process elimination diagnose pathology. Autoimmune Encephalitis can broken down into possible, probable, definitive diagnoses based on antibody results. this probable encephalitis yield positive after extensive possible causes encephalitis.