It’s one of those topics, where psychiatry has a century long history of finding the right terminology, establishing their own understanding of a strange syndrome, while neurology has a completely different approach and develops new diseases for an explanation.
We discuss the case of a classic catatonic patient with a breeze of weirdness and a touch of malignancy (fever, tachycardia): mutistic, negativistic, rigorous, yet able to turn away and even walk out of the ER. Here, the differential is not too broad, yet we go through it and then discuss the various investigations you could order. This is what we came up with:
- Non-convulsive status – EEG
- Encephalitis – LP, MRI, HSV-PCR
- Wilson’s – eyes, liver, caeruloplasmin, copper @ urine
- Hashimoto’s – antibodies
- NMDAR- and other weird autoimmune/paraneoplastic encephalitides, which may be MRI negative – LP, bands, antibody panel
- Parkinson crisis
- Septic encephalopathy
- Toxic encephalopathy
- Neuroleptic malignan / serotonergic syndrome
The easiest way to deal with it, though, is to get a vial of lorazepam and give it. If he gets better within hours – syndrome away! You still have to find the cause of it. Remember that non-convulsive status resolves in seconds rather than minutes or hours after lorazepam.
Nowadays, neurologists tend to think of NMDAR-encephalitis, before they even consider catatonia and probably they are right in a few percent of the cases, but the ruling is still out there.
- The chapter on catatonia of the book Psychiatry for the Neurologist.