We enjoyed the observation by Hirsch that indeed shares many similarities with our own cases and further supports an association between qualitative disturbances of olfactory perception and early PD. At variance with our report, however, the phantosmias his patient experienced were essentially unpleasant, challenging the hypothesis that the pleasant nature of the spontaneous olfactory hallucinations we observed may for yet unknown reasons favor a neurodegenerative origin. We take this opportunity to briefly describe another intriguing patient who appears to have sequentially experienced different forms of phantosmia that could be attributed to distinct mechanisms.
Burkhard PR, Landis BN. Parkinsonism: The Hyposmia and Phantosmia Connection—Reply. Arch Neurol. 2009;66(4):538-542. doi:10.1001/archneurol.2009.39