The origin and nature of the complex autoantibody profile in cerebrospinal fluid.

The present study demonstrates, using human protein microarrays and plasma and cerebrospinal fluid samples obtained pre-surgically and simultaneously from 46 hip fracture repair patients, that CSF exhibits an extraordinarily complex IgG autoantibody profile composed of thousands of autoantibodies. We show that the pattern of expression levels of individual autoantibodies in CSF closely mimics that in the blood, regardless of age, gender or the presence or absence of disease, indicative of a blood-based origin for CSF autoantibodies. In addition, using five longitudinal serum samples obtained from one healthy individual over a span of nine years, we found that blood autoantibody profiles are remarkably stable over a long period of time, and that autoantibody profiles in both blood and CSF show features that are common among different individuals as well as individual-specific. Lastly, we demonstrate that an elevated CSF/plasma autoantibody ratio is more common in elderly hip fracture repair patients that experienced post-operative delirium than in non-delirium subjects, thus highlighting the crucial role that blood-brain and/or blood-CSF barrier compromise may play in the development of post-operative delirium.

Detection of early-stage Alzheimer's pathology using blood-based autoantibody biomarkers in elderly hip fracture repair patients.

Post-operative delirium (POD) is the most common complication following major surgery in non-demented older (>65 y/o) patients. Patients experiencing POD show increased risk for future cognitive decline, including mild cognitive impairment (MCI) and Alzheimer's disease (AD) and, conversely, patients with cognitive decline at surgery show increased risk for POD. Here, we demonstrate that a previously established panel of AD-driven MCI (ADMCI) autoantibody (aAB) biomarkers can be used to detect prodromal AD pre-surgically in individuals admitted into the hospital for hip fracture repair (HFR) surgery. Plasma from 39 STRIDE (STRIDE: A Strategy to Reduce the Incidence of Postoperative Delirium in Elderly Patients) HFR patients and sera from 25 age- and sex-matched non-demented and non-surgical controls were screened using human protein microarrays to measure expression of a panel of 44 previously identified MCI aAB biomarkers. The predictive classification accuracy of the aAB biomarker panel was evaluated using Random Forest (RF). The ADMCI aAB biomarkers successfully distinguished 21 STRIDE HFR patients (CDR = 0.5) from 25 matched non-surgical controls with an overall accuracy of 91.3% (sensitivity = 95.2%; specificity = 88.0%). The ADMCI aAB panel also correctly identified six patients with preoperative CDR = 0 who later converted to CDR = 0.5 or >1 at one-year follow-up. Lastly, the majority of cognitively normal (CDR = 0) STRIDE HFR subjects that were positive for CSF AD biomarkers based on the A/T/N classification system were likewise classified as ADMCI aAB-positive using the biomarker panel. Results suggest that pre-surgical detection of ADMCI aAB biomarkers can readily identify HFR patients with likely early-stage AD pathology using pre-surgery blood samples, opening up the potential for early, blood-based AD detection and improvements in peri- and postoperative patient management.

Epidemiologic analysis of central vein catheter infection in burn patients.

BACKGROUND AND OBJECTIVES: Currently, there are no well-defined guidelines or criteria for catheter-site care in burn patients, and there is little information about the epidemiology of central vein catheter (CVC) infection in such patients. This study aimed at addressing the epidemiological aspect of CVC infection in a sample of Iranian burn patients admitted to the largest referral burn center in Iran, Motahari Burn Center. MATERIALS AND METHODS: A total of 191 burn patients were eligible for the study. Catheter related blood stream infection (CRBSI) was diagnosed according to suspected line infection, sepsis or blood culture growing bacteria, which could not have been associated with another site. RESULTS: Of the 191 patients in this study, 45 males (23.68%) and 19 females (10%) had positive blood culture, confirming CV line infection. Patients who were burned by gas, gasoline ignition or burning Kerosene had the highest incidence of CV line infection. In contrast, patients burned by alcohol, pitch or thinner had the lower rate of CV line infection. Incidence of CV line infection was higher in patients with delay in presentation to the burn center (55.2%) when compared to those who presented without delay (22.8%). Pseudomonas aeruginosa was the most frequent colonizer of the wound culture (52.4%), the dominant strain of the first catheter tip culture (35%) and the dominant strain of the same day blood samples (53.8%). The mortality rate in patients diagnosed with CRBI was 21.9%. CONCLUSION: One of the important factors related to CV line infection is delay inpresentation to the burn center. The rate of CV line infection was 20.64 in catheter days.