Olfactory deficit and hippocampal volume loss for early diagnosis of Alzheimer disease: a pilot study.

BACKGROUND: The aim of this pilot study was to verify the role of olfactory test and volumetric magnetic resonance imaging measure of hippocampus to predict conversion from mild cognitive impairment to Alzheimer disease (AD). MATERIALS AND METHODS: Eighteen patients with amnesic mild cognitive impairment, broadly defined, were followed at 12 months. Hypothesized baseline predictors for follow-up conversion to AD were olfactory deficit and hippocampal volumes loss. RESULTS: In the 1-year follow-up, 5 patients converted to AD. The 2 clinical predictors olfactory test and hippocampal volume loss showed the same sensitivity of 92.3% but the olfactory test showed a higher specificity than the hippocampal volume loss (75% vs. 60%). CONCLUSIONS: Our findings suggest the potential utility of olfactory test and hippocampal volume loss for early detection of AD.

Periprosthetic joint infections: a clinical practice algorithm.

PURPOSE: periprosthetic joint infection (PJI) accounts for 25% of failed total knee arthroplasties (TKAs) and 15% of failed total hip arthroplasties (THAs). The purpose of the present study was to design a multidisciplinary diagnostic algorithm to detect a PJI as cause of a painful TKA or THA. METHODS: from April 2010 to October 2012, 111 patients with suspected PJI were evaluated. The study group comprised 75 females and 36 males with an average age of 71 years (range, 48 to 94 years). Eighty-four patients had a painful THA, while 27 reported a painful TKA. The stepwise diagnostic algorithm, applied in all the patients, included: measurement of serum C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) levels; imaging studies, including standard radiological examination, standard technetium-99m-methylene diphosphonate (MDP) bone scan (if positive, confirmation by LeukoScan was obtained); and joint aspiration with analysis of synovial fluid. RESULTS: following application of the stepwise diagnostic algorithm, 24 out of our 111 screened patients were classified as having a suspected PJI (21.7%). CRP and ESR levels were negative in 84 and positive in 17 cases; 93.7% of the patients had a positive technetium-labeled bone scan, and 23% a positive LeukoScan. Preoperative synovial fluid analysis was positive in 13.5%; analysis of synovial fluid obtained by preoperative aspiration showed a leucocyte count of > 3000 cells µ/l in 52% of the patients. CONCLUSIONS: the present study showed that the diagnosis of PJI requires the application of a multimodal diagnostic protocol in order to avoid complications related to surgical revision of a misdiagnosed "silent" PJI. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

NOX2 up-regulation is associated with artery dysfunction in patients with peripheral artery disease.

OBJECTIVE: Oxidative stress seems to play a role in impairing flow-mediated dilation (FMD) in patients with peripheral artery disease (PAD) but the underlying mechanism is still undefined. We evaluated whether NOX2, the catalytic core of NADPH oxidase, the most important producer of reactive oxidant species (ROS), is implicated in impairing FMD. METHODS: We measured FMD, urinary isoprostanes, a marker of oxidative stress, nitric oxide generation by serum levels of nitrite/nitrate (NOx), and serum levels of soluble NOX2-derived peptide (sNOX2-dp), a marker of NOX2 activation, in 50 PAD patients and 50 controls. Also, we performed an interventional cross-over study to assess if propionyl-L-carnitine (PLC) (6g/day), vs. placebo, was able to affect FMD via an oxidative stress-mediated mechanism. RESULTS: Compared to controls, patients with PAD had enhanced sNOX2-dp and isoprostanes and reduced NOx and FMD. Multiple linear regression analysis showed that FMD was independently associated with sNOX2-dp. After PLC infusion FMD increased while sNOX2-dp and isoprostanes significantly decreased; no changes were observed after placebo. In vitro study by incubating platelets or white cells with PLC demonstrated a significant inhibition of p47(phox) translocation on cellular surface and ROS generated by NOX2 activation. CONCLUSION: This study suggests that in PAD patients ROS generated by NOX2 contribute to reduce FMD and that the administration of an antioxidant is able to improve arterial dilatation via NOX2 inhibition.