We appreciate the comments of Dr Zeimer, who correctly notes our failure to mention limbic encephalitis as a rare cause of delirium and the possible contribution of this cause to the nonreversibility of delirium in our study.1 Limbic encephalitis is regarded as a specific type of paraneoplastic encephalomyelitis.2 Both paraneoplastic encephalomyelitis and sensory neuropathy are associated with the presence of anti-Hu antibodies, and in one series, the neurological presentation predated the cancer diagnosis in up to 60% of patients.3 Our study design stipulated the conduct of laboratory and other investigations that were part of routine practice in our palliative care unit. This excluded measurement of anti-Hu antibodies.
Lawlor PG, Gagnon B, Mancini IL, Pereira JL, Hanson J, Suarez-Alamazor M, Bruera ED. Delirium as a Predictor of Survival in Older Patients With Advanced Cancer—Reply. Arch Intern Med. 2000;160(18):2866-2868. doi: