Incidence and outcome of functional stroke mimics admitted to a hyperacute stroke unit.

BACKGROUND: Some patients admitted to acute stroke units are diagnosed as stroke mimics. A minority have a functional neurological disorder ('functional mimics'). AIMS: To determine the incidence of functional stroke mimics admitted to a hyperacute stroke unit (HASU); to compare their clinical characteristics with medical mimics and stroke cases and obtain information about outcomes. METHODS: Patients admitted to the King's College Hospital HASU between 2011 and 2012 were analysed. Data were obtained from the Stroke Improvement National Audit Programme (SINAP) database. Expert consensus diagnosis was used to classify functional mimics. Follow-up information was obtained from a retrospective case series in primary care over the year following discharge. RESULTS: 1165 patients were admitted to the HASU; 904 patients with stroke (77.6%), 163 medical mimics (14%) and 98 functional mimics (8.4%). Functional mimics were significantly more likely to be female (63.3%) versus 49.7% medical mimics and 45.5% stroke, and younger (mean age (SD)) 49.1 (18.8) than medical mimic (63.5 years (16.7)) and stroke cases (71 years (15.5)). Weakness and slurred speech were the commonest presentations of functional mimics and diagnostic MRI was used more often. Clinician recorded visual and speech symptoms and neglect were significantly more frequent in patients with stroke than either mimic group. Of the 68 functional mimics on whom follow-up information was obtained, 40 (59%) were referred to another service most often for a psychologically-based intervention. CONCLUSIONS: Functional stroke mimics are an important subgroup admitted to acute stroke services and have a distinct demographic and clinical profile. Their outcomes are poorly monitored. Services should be developed to better diagnose and manage these patients.

Multidimensional LC-MS/MS enables simultaneous quantification of intact human insulin and five recombinant analogs in human plasma.

This work provides a multidimensional method for the simultaneous, direct quantification of intact human insulin and five insulin analogs in human plasma. This investigation solves both the selectivity and sensitivity problems encountered for accurate quantification of insulins in plasma since the former is not possible with conventional assays and the latter with conventional LC-MS/MS. The method uses a mixed-mode SPE and a multidimensional LC method including a solid-core particle column containing an anion exchange stationary phase. Matrix factors for all analogs were calculated in 6 sources of human plasma and CVs of the matrix factors were <15% in all cases supporting the selectivity of the method, while achieving LLOQs of 50-200 pg/mL (1.4-5.6 µIU/mL) for each insulin from 250 µL of human plasma. The average accuracy for the standard curve points in extracted human plasma was 99-100%. Average inter- and intraday accuracies for QC samples were 98% and 94%, respectively. Average inter- and intraday precisions for QC samples were 7.5 and 5.3%, respectively. Patient samples were analyzed in a blind study and results concurred with their diabetes multidosing regimes. The study also demonstrated that the presence of high levels of human insulin and bovine insulin does not interfere with quantification of any of the analyzed analogs. We propose this method for the accurate pharmacokinetic monitoring of diabetic patients, for sport antidoping and forensic toxicology analysis.