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Olfaction is typically impaired in idiopathic Parkinson's disease (IPD), but its role is uncertain in monogenic PD. Diminished color discrimination has been suggested as another early sign of dopaminergic dysfunction but not been systematically studied. Furthermore, it is unknown whether both deficits are linked. We examined 100 patients with IPD, 27 manifesting mutation carriers (MC), 20 nonmanifesting mutation carriers (NMC), and 110 controls. Participants underwent a standardized neurological examination, the University of Pennsylvania Smell Identification Test (UPSIT), the Farnsworth-Munsell (FM) color discrimination test, and mutation testing in known PD genes. The monogenic group consisted of 15 Parkin (6MC/9NMC), 17 PINK1 (10MC/7NMC), 8 LRRK2 (4MC/4NMC), 3 SNCA (MC), and 4 ATP13A2 (MC) carriers. Olfaction was most impaired in IPD (UPSIT percentiles 10.1 ± 13.5) compared with all other groups (MC 13.8 ± 11.9, NMC 19.6 ± 13.0, controls 33.8 ± 22.4). Within MC, carriers of two mutations in Parkin and PINK1 showed higher UPSIT percentiles than LRRK2 and SNCA carriers. Color discrimination was reduced in IPD (FM total error score 134.8 ± 92.7). In MC (122.4 ± 142.4), the reduction was most pronounced in LRRK2, NMC (80.0 ± 38.8) were comparable with controls (97.2 ± 61.1). UPSIT and FM scores were correlated in the control (r = -0.305; P = 0.002) and the IPD group (r = -0.303; P = 0.006) but not among mutation carriers. First, we confirmed olfaction and color discrimination to be impaired in IPD and suggest olfaction to be a premotor sign. Second, olfaction differed between carriers with one and two mutations in Parkin/PINK1-associated PD. Third, olfaction and color discrimination impairment do not necessarily evolve in parallel., (© 2010 Movement Disorder Society.)

Aldicarb toxicosis was diagnosed in 200 sheep that died suddenly. Carbamate insecticide toxicosis was suspected based on observed clinical signs (hypersalivation, diarrhea, urination, paddling, seizures, miosis, and deaths occurring within 1 hour). Tissue samples were submitted from 4 Columbian ewes for pathologic and analytical evaluation. Severe diffuse pulmonary edema was observed on gross and histologic examination. Inhibition of cholinesterase activity in retina (21.2-68.1% of normal activity, n = 3), brain (40.6-45.6% of normal activity, n = 3), and whole blood (27% of normal activity, n = 1) supported a diagnosis of carbamate toxicosis. Reversal of brain and whole blood cholinesterase activities (reactivation factor greater than 1.4) following an in vitro 1 hour incubation at 37 C was also consistent with carbamate poisoning. Aldicarb toxicosis was confirmed following its detection in rumen contents at 1.5, 5.5, and 334 ppm using both high-pressure liquid chromatography with UV detection and gas chromatography with nitrogen/phosphorus detection.