Ascertainment bias in dementias: a secondary to tertiary centre analysis in Central Italy and conceptual review.

BACKGROUND AND AIMS: Ascertainment bias (AB) indicates a bias of an evaluation centre in estimating the prevalence/incidence of a disease due to the specific expertise of the centre. The aim of our study was to evaluate classification of different types of dementia in new cases appearing in secondary and tertiary centres, in order to evidence possible occurrence of AB in the various (secondary to tertiary) dementia centres. METHODS: To assess the mechanism of AB, the rates of new cases of the different forms of dementia reported by different centres were compared. The centres involved in the study were 11 hospital-based centres including a tertiary centre, located in the University Department of Clinical Neurology. The tertiary centre is endowed with state-of-the-art diagnostic facilities and its scientific production is prominently focused on dementia with Lewy bodies (DLB) thus suggesting the possible occurrence of a bias. Four main categories of dementia were identified: Alzheimer's disease (AD), DLB, fronto-temporal dementia (FTD), vascular dementia (VaD), with other forms in a category apart. The classification rate of new cases of dementia in the tertiary centre was compared with rates reported by secondary centres and rates of recoding were calculated during a follow-up of 2 years. RESULTS: The study classified 2,042 newly diagnosed cases of dementia in a population of 1,370,000 inhabitants of which 315,000 were older than 65. AD was categorized in 48-52 % of cases, DLB in 25-28 %, FTD in 2-4 % and VaD in 17-28 %. During the 2-year follow-up the diagnosis was re-classified in 40 patients (3 %). The rate of recoding was 5 % in the tertiary centre, 2-8 % in referrals from secondary to tertiary centre, 2-10 % in recodings performed in secondary centres and addressed to tertiary centre. Recoding or percentages of new cases of AD or DLB were not different in the comparison between secondary or between secondary and tertiary centres. FTD and VaD were instead significantly recoded. CONCLUSION: The results of the study suggest that in a homogeneous area, AB is not interfering with diagnosis of AD or DLB.

Cefixime-induced nonconvulsive status epilepticus.

Nonconvulsive status epilepticus (NCSE) is an epileptic condition lasting >30 min, clinically manifested by an altered mental state and associated with continuous epileptiform activity on the electroencephalogram. NCSE is a common yet still under recognized condition and delay in diagnosis and treatment may be associated with increased mortality as well as cognitive/behavioral consequences. We described an epileptic female patient assuming carbamazepine (900 mg/day) and levetiracetam (3,000 mg/day), seizure free for more than 10 years, who developed NCSE during cefixime treatment, a third-generation cephalosporin compound that along with penicillins is classified within the b-lactam class of antibiotics. In our report we outline the importance and the difficulty to choose secure antibiotic treatment in epileptic patients, we discuss the possible mechanisms by which cephalosporins induce neurotoxicity and the need to stress family components questioning about new drugs assumed. Finally we highlight the value of the EEG recording to diagnose NCSE and treat it adequately and promptly.

[The role of D-dimer in aortic dissection]. / Il D-dimero nella dissezione aortica.

OBJECTIVES: The aim of this retrospective study is to indicate the correlation between the grade of the extent of the aortic pathology, the presence of complications, the evolution of the pathology value of the D-dimer in all the patients with aortic dissection in order to know a prognostic role a short-long time of this test. MATERIALS AND METHODS: Only in 40 patients were possible to determine the value of D-dimer priol of these patients were not received invasive cares. The patients are divided into 4 classes in accordance with the extent of the aortic pathology valued TAC images and after we have taken in observation the presence of clinical complications shown and the positive history for chronic aortic dissection. RESULTS: The elevation of D-dimer is strictly associated with the extent of the aortic dissection. The value of D-dimer is more elevated during the progress of the pathology and in the presence of clinical complications than during chronic aortic dissection. CONCLUSIONS: The D-dimer is considered a diagnostic marker by the clinicians during the acute setting of the aortic dissection. A lot of points of view should be valued and cleared, its possible to attribute a prognostic role at the D-dimer during the acute aortic dissection.