Incidence Of Positive Cultures Research Articles

MicroRNA expression analysis in peripheral blood and soft-tissue of patients with periprosthetic hip infection.

Current diagnostic tools are not always able to effectively identify periprosthetic joint infections (PJIs). Recent studies suggest that circulating microRNAs (miRNAs) undergo changes under pathological conditions such as infection. The aim of this study was to analyze miRNA expression in hip arthroplasty PJI patients. This was a prospective pilot study, including 24 patients divided into three groups, with eight patients each undergoing revision of their hip arthroplasty due to aseptic reasons, and low- and high-grade PJI, respectively. The number of intraoperative samples and the incidence of positive cultures were recorded for each patient. Additionally, venous blood samples and periarticular tissue samples were collected from each patient to determine miRNA expressions between the groups. MiRNA screening was performed by small RNA-sequencing using the miRNA next generation sequencing (NGS) discovery (miND) pipeline. Overall, several miRNAs in plasma and tissue were identified to be progressively deregulated according to ongoing PJI. When comparing the plasma samples, patients with a high-grade infection showed significantly higher expression levels for hsa-miR-21-3p, hsa-miR-1290, and hsa-miR-4488, and lower expression levels for hsa-miR-130a-3p and hsa-miR-451a compared to the aseptic group. Furthermore, the high-grade group showed a significantly higher regulated expression level of hsa-miR-1260a and lower expression levels for hsa-miR-26a-5p, hsa-miR-26b-5p, hsa-miR-148b-5p, hsa-miR-301a-3p, hsa-miR-451a, and hsa-miR-454-3p compared to the low-grade group. No significant differences were found between the low-grade and aseptic groups. When comparing the tissue samples, the high-grade group showed significantly higher expression levels for 23 different miRNAs and lower expression levels for hsa-miR-2110 and hsa-miR-3200-3p compared to the aseptic group. No significant differences were found in miRNA expression between the high- and low-grade groups, as well as between the low-grade and aseptic groups. With this prospective pilot study, we were able to identify a circulating miRNA signature correlating with high-grade PJI compared to aseptic patients undergoing hip arthroplasty revision. Our data contribute to establishing miRNA signatures as potential novel diagnostic and prognostic biomarkers for PJI.

RETROSPECTIVE ANALYSIS OF BLOOD CULTURES AND THEIR ASSOCIATION WITH CLINICAL FINDINGS AND OUTCOME IN GREEN SEA TURTLES (CHELONIA MYDAS) AT A FLORIDA SEA TURTLE REHABILITATION FACILITY, 2017-2020.

Septicemia is commonly suspected of sea turtles entering rehabilitation. However, blood culture results of green sea turtles (Chelonia mydas) are infrequently reported in the literature. Aerobic blood cultures were performed for intake examinations of 167 green sea turtles undergoing rehabilitation at Brevard Zoo's Sea Turtle Healing Center, Melbourne, Florida, USA from 2017 to 2020. The incidence of positive cultures during intake examinations was 24% (40/167). The most common bacterial isolates identified were Vibrio alginolyticus, Shewanella algae, Achromobacter xylosoxidans, Photobacterium damselae, Sphingomonas paucimobilis, and Vibrio parahaemolyticus. There was a statistically significant association (P < 0.05) between culture status and evidence of external injury. There was no significant association between culture status and Caryospora-like coccidia infection, or fibropapillomatosis. Culture-positive turtles had significantly lower (P < 0.05) total white blood cell, lymphocyte, monocyte, total protein, albumin, and calculated globulin values compared to turtles with negative blood cultures. Significantly more culture-positive turtles died in rehabilitation compared to culture-negative (P = 0.042). Positive blood cultures suggestive of septicemia are commonly found during intake examinations at a Florida sea turtle rehabilitation facility.

Comparison of Efficacy of Vacuum Dressing Versus Conventional Dressing Over Autologous Split Skin Grafts in Burn Wounds: A Single-Center Prospective Cohort Study.

This study was carried out to compare the efficacy of vacuum dressing and conventional dressing over split skin grafts in burn patients. It was a single-center prospective cohort study on patients, with less than 40% TBSA burn, undergoing skin grafting at 2 different sites simultaneously over the burn wounds. One site underwent conventional dressing following grafting, and the other underwent vacuum dressing. The primary objective was to compare the percentages of skin graft uptake on Day 5 and Day 14. The secondary objectives were to compare the duration of dressings, time for complete epithelization, need for regrafting, and wound swab culture positivity rates. Three independent examiners assessed the efficacy of dressings in terms of epithelization percentage, need for continued dressing, graft loss, wound swab culture positivity rate, and qualitative assessment of grafts. A total of 16 patients were included in the study. The graft loss, number of days of dressings, and complete epithelization time were statistically lower in the negative-pressure wound therapy (NPWT) group compared with the conventional group (P values .007, .006, and 0009, respectively). The percentage of epithelization was also found to be higher in the NPWT group (P = .006). The incidence of positive cultures and clinically significant graft loss was found to be lower in the NPWT group. However, this was not found to be statistically significant. NPWT dressings can be used in burn wounds following skin grafting and have been found to reduce the time for epithelization compared to conventional dressing.

Bacterial contamination in the operating room at Hue Central Hospital, 2nd branch

ABSTRACT Objectives: This study aims to evaluate the microbial contamination level and identify bacterial colonization of the operating room in the hospital. Methods: Three sampling procedures were used in this study, which includes swabbing, air sampler and contact agar plate. Collected samples from 8 ORs were transported and microbiologically processed using standard procedures. Bacteria were identified by morphological, biochemical tests and Vitek 2 Compact system. Microbiological criteria were based on recommendation of the Ministry of Health. Results: The incidence of positive cultures was 285/600 (47.50%). The most common isolates were Gram - positive bacteria (98.25%) while low rate of Gram - negative bacteria (1.75%) was surveyed with Pseudomonas sp. (0.7%) and Enterobacter cloacae (1.05%). The water used for surgical hand washing illustrated the existence of Staphylococcus blanc (60%) and each of Pseudomonas sp. and Enterobacter cloacae (20%). Air contamination were observed with Bacillus sp. (46.90%) and Staphylococcus blanc (53.10%). Environmental surfaces were detected 7 species, of which 4 threaten strains including Staphylococcus aureus accounted for 5.55%, followed by Streptococcus β - hemolytic (0.79%), Pseudomonas sp. (0.79%) and Enterobacter cloacae (1.59%). Surgeons’s hand samples were isolated with Bacillus sp. (14.55%) and Staphylococcus blanc (1.81%). The rate samples of ORs surfaces reaching level A and B accounted for 91.49% and 8.51% while none of the samples approach level C and level D. The rate of qualified samples in terms of air, water for surgical hand washing, surfaces of medical instruments and surgeons’ hands was remarkably high with 87.59%, 98.44%, 95.24% and 100%, respectively. Conclusion: Our study showed various bacteria isolated, of which pathogenic species occupied very low percentage. Especially, the rate of samples in the study that meet microbiological standards was remarkably high according to Ministry of Health recommendation.

IMPROVING NEONATAL OUTCOME BY STUDYING THE INCIDENCE OF MATERNAL GROUP B STREPTOCOCCUS (GBS) COLONIZATION AMONGST PREGNANT WOMEN: A PROSPECTIVE OBSERVATIONAL STUDY

Background And Objectives: Group B streptococcus (GBS) colonization during pregnancy can lead to invasive infections in neonates including meningitis or sepsis. The major risk factor for the neonatal disease is the rectovaginal colonization of GBS during pregnancy and delivery. The objectives of this study were as follows: 1) To screen antenatal patients at 35-37 weeks of gestation for GBS colonization. 2) To determine the prevalence of GBS among pregnant women. 3) To formulate an antibiotic policy with respect to antepartum antibiotic prophylaxis and empiric choice of antibiotics for early-onset neonatal sepsis. 4) To ascertain the maternal and neonatal outcomes in pregnant women with GBS colonization. Methods: A prospective observational study was conducted among 50 obstetric patients at 35-37 weeks of gestation attending the outpatient and inpatient departments of a tertiary care hospital. High vaginal and rectal swabs were collected and sent for culture and sensitivity testing using the standard culture methods. The incidence of positive cultures was noted and was taken up as a reference for statistical calculations. Results: Out of the 50 vaginal samples, 1 sample showed GBS positivity having a prevalence of 2%. Rectal swabs did not grow GBS for all samples. The mother and the newborn did not show any symptoms or signs due to GBS. GBS grown in vaginal culture was highly sensitive to Penicillin's, Cephalosporins, Clindamycin, Daptomycin, Vancomycin, Meropenem, and Linezolid. Conclusion:Based on our ndings, screening patients with routine rectovaginal swabs may not be necessary for our population. Also, empiric treatment with antibiotics for GBS in symptomatic mothers cannot be justied and hence GBS should be considered an insignicant pathogen

Evaluation of sputum cultures in children with spinal Muscular atrophy

BackgroundSpinal Muscular Atrophy (SMA) is a severe neuromuscular disorder. Despite increased survival due to novel therapies, morbidity from respiratory complications still persists. We aim to describe these patients' sputum cultures as an expression of chronic infectious airway disease. MethodsRetrospective review of medical records of all children with SMA followed at the multidisciplinary respiratory neuromuscular clinic at Schneider Childrens' Medical Center of Israel over a 16-year period. Sputum cultures were obtained during routine visits or pulmonary exacerbations. ResultsSixty-one SMA patients, aged 1 month to 21 years, were included in this cohort. Of these, sputum cultures were collected from 41 patients. Overall, 288 sputum cultures were obtained, and 98 (34%) were negative for bacterial growth. For the first culture taken from each patient, 12 out of 41 (29%) were sterile. The most common bacteria were pseudomonas aeruginosa (PSA) (38%) and staphylococcus aureus (19.6%). PSA was found in SMA type I patients more frequently than in type II patients (15/26 = 58% vs 4/13 = 31%, p < 0.001). PSA infection was positively associated with noninvasive ventilation, recurrent atelectasis, recurrent pneumonias, swallowing difficulties, but no significant association was found with cough assist machine usage. The incidence of positive cultures did not differ between those treated with Onasemnogene abeparvovec or Nusinersen compared to those without treatment, but the age of first PSA isolation was slightly older with Nusinersen treatment (p = 0.01). ConclusionsAirway bacterial colonization is common in SMA type I patients and is not decreased by Onasemnogene abeparvovec or Nusinersen treatment.

Biofilm Producing Pseudomonas Aeruginosa in Patients with Lower Respiratory Tract Infections

Background and Aim: Pseudomonas aeruginosa is a vital pathogen causing major life-threatening infections among respiratory disease patients that leads to higher morbidity and mortality. Lower respiratory tract infections (LRTIs) are amongst these infections commonly found in hospitalized patients. Antibiotic tolerant biofilms formation and bacterium high intrinsic resistance to antibiotics make these infections difficult to treat. The present study aimed to assess the biofilm producing pseudomonas aeruginosa in lower respiratory tract infections patients. Methodology: This cross-sectional study was carried out on 246 Lower respiratory tract infections patients admitted to ICUs of Sharif Medical and Dental College Lahore and Mohi-ud-Din Teaching Hospital, Mirpur Azad Kashmir for the duration from June 2021 to December 2021. The signs and symptoms of LRTIs were investigated in each patient. Prior to study conduction, ethical approval was obtained from the institutes research and ethical committee. Each individual provided written informed consent. Identification of isolated organisms and antimicrobial sensitivity was done. Microtiter method was used for all the isolated, to imperil the isolates of P. aeruginosa for biofilm detection. SPSS version 25 was used for the data analysis. Results: Of the total 246 specimens consisted of sputum 198 (80.5%), pleural fluid 19 (7.7%), suction tube 16 (6.5%), and tracheostomy tip specimens 13 (5.3%). The incidence of positive culture was 78 (31.7%). Out of 78 positive cultures, sputum 56 (71.8%) was the major factor followed by pleural fluid 3 (3.8%), suction tube 12 (15.4%) and tracheostomy tip 7 (9.0%). Of the 78 positive specimens, the prevalence of single bacterium and poly-microbial infection was 58 (74.4%) and 20 (25.6%) respectively. The poly-microbial infection consisted of sputum 10 (50%), pleural fluid 1 (5.0%), suction tube 6 (30.0%), and tracheostomy tube 3 (15%). Out of 78 positive culture specimens, isolated gram-negative bacteria were 102, out of which K. pneumonia and P. aeruginosa were present in 46 (45.1%) and 24 (23.5%) respectively. Regarding the resistance pattern of gram-negative respiratory pathogens, Cefepime (86.9%) and ceftriaxone (91.9%) were given higher resistance by K. pneumoniae. Likewise, higher numbers of Acinetobacter spp provided resistance to cefepime (86.7%) and ceftriaxone (87%). Out of 24 P. aeruginosa isolates, biofilm producers were found in 16 isolates, in which the incidence of strong, moderate, and weak biofilm producers was 3 (18.7%), 5 (31.3%), and 8 (50%) respectively. Sputum in 11 (68.8%) was the prevalent biofilm producer isolates followed by suction tube 4 (25%) and tracheostomy tube 1 (6.3%). The incidence of inpatients and outpatients were 15 (93.8%) and 1 (6.2%) respectively. Conclusion: Our study concluded that gram-negative bacteria was the predominant and had increased resistance to antibiotics in Lower respiratory tract infections (LRTIs) patients. In LRTIs, the most common organism was K. pneumonia. Also, P. aeruginosa isolated in LRTIs patients were susceptible to producing biofilm. Biofilm producers had higher resistance than biofilm non-producers. Keywords: Biofilm producing P. aeruginosa, K. pneumonia, Lower respiratory tract infections

The Sepsis Bundle Effect: An Evaluation of Culture Results and Utilization in Pediatric Appendicitis.

Sepsis prevention pathways, which often include blood and urine cultures, are common in children's hospitals. Fever and tachycardia, signs often seen in patients with appendicitis, frequently trigger these pathways. We hypothesized that cultures were frequently obtained in children with appendicitis. We conducted a single-center retrospective cohort study evaluating children with image-confirmed appendicitis from 4/1/2019 to 10/1/2020, coinciding with the initiation of sepsis prevention pathways. Factors associated with culture acquisition, as well as culture results, treatment, and outcomes were evaluated. Six hundred and fifty eight children presented with acute appendicitis during the 1.5-year period, with a median age of 10.67 years (interquartile range (IQR) 8.17-14.08). Cultures were obtained in 22.9%, including blood culture (BCx) in 8.1% and urine culture (UCx) in 17.9%. Culture acquisition decreased by 17.6% after sepsis protocol initiation. Blood culture acquisition correlated with fever (P = .003) and younger age (P = .03), whereas the attainment of BCx and UCx was associated with female sex (P = .04, P < .0001), complicated appendicitis (P = .0001, P = .03), and unknown diagnosis (P < .0001, P < .0001). There were five positive UCx (4.24%); however, all remained asymptomatic despite a short antibiotic duration dictated by institutional appendicitis protocol. The one positive BCx (1.89%) was suspected contamination and not treated. The findings of this cohort suggest a low incidence of positive culture as well as lack of impact on clinical management in image-proven appendicitis and the initiation of a sepsis bundle without automatic culture acquisition may result in decreased culture attainment.

Are Dropped Bone Grafts Safe to be Re-used? - An Experimental Study Comparing Efficacy of Chlorhexidine, Povidone-Iodine and Alcohol.

Introduction:A dilemma arises when a bone graft or fracture fragment is accidentally dropped on the operation theatre floor and becomes contaminated. This study aimed to determine the efficacy of simple and readily available antiseptic solutions in disinfecting contaminated bones.Material and Methods:This experimental study involved 225 bone specimens prepared from discarded bone fragments during a series of 45 knee and hip arthroplasty surgeries. The bone fragments were cut into five identical cubes and were randomly assigned to either control (positive or negative), or experimental groups (0.5% chlorhexidine, 10% povidone-iodine or 70% alcohol). The control negative was to determine pre-contamination culture. All bone specimens, except the control negative group were uniformly contaminated by dropping on the operation theatre floor. Subsequently, the dropped bone specimens except for the control positive group, were disinfected by immersing in a respective antiseptic solution for 10 minutes, before transported to the microbiology laboratory for incubation.Results:The incidence of a positive culture from a dropped bone fragment was 86.5%. From the 37 specimens sent for each group, the incidence of positive culture was 5.4% (2 specimens) after being disinfected using chlorhexidine, 67.6% (25 specimens) using povidone-iodine and 81.1% (30 specimens) using alcohol. Simple logistic regression analysis demonstrated that chlorhexidine was significantly effective in disinfecting contaminated bones (p-value <0.001, odd ratio 0.009). Povidone-iodine and alcohol were not statistically significant (p-value 0.059 and 0.53, respectively). Organisms identified were Bacillus species and coagulase negative Staphylococcus. No gram-negative bacteria were isolated.Conclusion:A total of 0.5% chlorhexidine is effective and superior in disinfecting contaminated bones.

Clinical Outcomes Associated With Methylprednisolone in Mechanically Ventilated Patients With COVID-19.

BackgroundThe efficacy and safety of methylprednisolone in mechanically ventilated patients with acute respiratory distress syndrome due to coronavirus disease 2019 (COVID-19) are unclear. In this study, we evaluated the association between use of methylprednisolone and key clinical outcomes.MethodsClinical outcomes associated with the use of methylprednisolone were assessed in an unmatched, case-control study; a subset of patients also underwent propensity-score matching. Patients were admitted between March 1 and April 12, 2020. The primary outcome was ventilator-free days by 28 days after admission. Secondary outcomes included extubation, mortality, discharge, positive cultures, and hyperglycemia.ResultsA total of 117 patients met inclusion criteria. Propensity matching yielded a cohort of 42 well-matched pairs. Groups were similar except for hydroxychloroquine and azithromycin use, which were more common in patients who did not receive methylprednisolone. Mean ventilator free-days were significantly higher in patients treated with methylprednisolone (6.21±7.45 versus 3.14±6.22; P = 0.044). The probability of extubation was also increased in patients receiving methylprednisolone (45% versus 21%; P = 0.021), and there were no significant differences in mortality (19% versus 36%; P = 0.087). In a multivariable linear regression analysis, only methylprednisolone use was associated with higher number of ventilator-free days (P = 0.045). The incidence of positive cultures and hyperglycemia were similar between groups.ConclusionsMethylprednisolone was associated with increased ventilator-free days and higher probability of extubation in a propensity-score matched cohort. Randomized, controlled studies are needed to further define methylprednisolone use in patients with COVID-19.

Infectious Complications after High-Dose Chemotherapy and Autologous Stem Cell Transplantation for Hematologic Malignancies in a 12-Year Period in Hospital Britanico, Uruguay

Introduction: Autologous stem cell transplant (ASCT) plays a central role in the treatment of diverse diseases. Infection is one of the major causes of morbidity and costs of the procedure, representing the 2ndcause of death (24%) after primary disease (69%). Thus, preventing infections is a major goal.1There are no publications concerning infections in ASCT in our country.Patients and Methods: Retrospective single center study.Objectives: to compare the incidence of febrile neutropenia (FN) and characteristics of infections between 2 different antibacterial approaches. From January 2006 - December 2017, 279 ASCT have been done in our center. We included 266 patients with complete data: 249 received 1 ASCT and 17 received two. Anti-bacterial prophylaxis from 2006-2013 (Group 1) was ciprofloxacin from day 0 to neutrophil recovery. From 2013 to present (Group 2), levofloxacin was used. First febrile episode empirical treatment was Ceftazidime-Amikacin in Group 1 and Meropenem in Group 2.Results: Median age was 56 years (18-72). MM and NHL (79,7%), 40% in complete remission, were the prevailing diseases. Median CD34+ cells transplanted was 4,87 x 106/kg (0,88-37). Median duration of neutropenia was 11 days (9-32). (Table 1)Group 1: 28% had no FN episodes. Catheter-related and gastrointestinal were the most prevalent sites of infection. Positive cultures were 17,4%, 66,6% Gram+. 91% received Ceftazidime+Amikacine. A 2ndantibiotic was added in 52 patients (60%). Six patients required intensive care unit (ICU) admission (4.9%), due to pneumonia (3), sepsis (2) and viral encephalitis (1). Median days at discharge after ASCT was 17 (10-56); 20,6 for those who had FN episodes and 16,5 for those who did not (p= 0,004).Group 2: 13,8 % had no FN episodes. Pneumonia and catheter-related infections were the most prevalent sites of infection. Positive cultures: 20 %; 69% Gram +. 70 patients received an additional agent (56%).Six patients required ICU admission (4,1%), 1 due to pneumonia, 1 sepsis, 1 alitiasic cholecystitis, 1 catheter-related infection and pneumonia, 1 bradyarrhythmia and 1 atrial fibrillation. Median days at discharge after ASCT was +16 (12-62), 19,8 for those who experienced FN and 17 for those who did not (p=0,184).Incidence of FN was 72% in Group 1 and 86,2% in Group 2 (p=0,004). Culture-negativity was 82,6% in Group 1 and 80% in Group 2. In blood + cultures, Gram + agents represented 66.6% in Group 1 and 69% in Group 2 (p=0.68).Discussion: FN is common in ASCT (63-94%)2,3, implying longer hospitalization, more diagnostic procedures and increase in morbidity and mortality. Significant differences in FN incidence between groups, in favor of Ciprofloxacin prophylaxis (72% vs 86,2% (p=0,004) were found. The incidence of positive cultures was similar in both groups. Gram+ agents were the most common isolation. Prophylaxis with quinolones leaded to a low Gram negative bacteria isolation, as reported by others.4Most infectious episodes were associated with fever of unknown origin: 53 % in Group 1 and 56.8 % in Group 2, with differences in sites of infection's frequency: catheter-related infection prevailed in Group 1 and pneumonia in Group 2. (Table 2)We hypothesized that a better Gram+ coverage with Levofloxacin might have help to reduce the incidence of clinical catheter infections. A 2nd antibiotic was needed in 60% from Group 1 and 56% in Group 2 (p=0,47). Median to neutrophil recovery was shorter in Group 1 (+8 vs +10), (p=0,0001). ICU admission was mostly due to sepsis, similar in both groups (p=0,74). During hospitalization, 2 patients died of sepsis in Group 1 and 0 in Group 2. Mortality rate was 1,87 %, similar to international reports.5 Patients in Group 2 were older, with more advanced diseases and hypogammaglobulinemia, which may contribute to difference in favor of Ciprofloxacin group in terms of FN and days to hematopoiesis recovery. (Table 3)Levofloxacin prophylaxis was not associated with an increase in resistant bacteria nor Clostridium difficile infection.Conclusions: The incidence of FN in ASCT was high. Levofloxacin prophylaxis was associated with more FN episodes and later discharge. Epidemiology and severity of infections and 2nd antibiotic requirement were comparable in both groups. Patients admitted for ASCT in the last 7 years had additional risk features that may contribute to explain the differences found. Mortality rate was low in both groups. DisclosuresNo relevant conflicts of interest to declare.

184 Dog-Assisted Therapy in the Emergency Department: Identifying Potential Risks of Clinically Significant Microbial Transmission

Dog- assisted therapy (DAT) has been shown to be useful in improving educational, psychological, and motivational effectiveness in regards to patient recovery. Petting dogs has been shown to have relaxing effects mediated by the release of serotonin, prolactin, and oxytocin, and has significant positive effects on cardiovascular health. Dogs are known to be a major reservoir for both viral and bacterial zoonotic infections including Rabies, Norovirus, Pasturella, Salmonella, Campylobacter, Bordatella, Coxiella, and methicillin-resistant Staphylococcus aureus (MRSA). There have been some case reports illustrating the possibility of transmission of antibiotic-resistant bacteria causing infection from pets to humans. This study sought to determine the presence of common “problematic” pathogens potentially carried by a group of emergency department (ED) therapy dogs, namely MRSA, E. Coli, Clostridium difficile, and Pseudomonas. It is hypothesized that the incidence of positive cultures would be negligible. A convenience sample of 7 therapy dogs was swabbed (coat, nose, and paws) before and after walking through the ED visiting patients. One perianal swab from each dog was obtained to test for Clostridium difficile (C. diff). Samples were cultured on plates containing Blood Agar, Chocolate Agar, Colistin and Naladixic acid (CNA), and MacConkey Agar (MAC). These culture mediums were specifically selected to optimize the growth of the pathogens of concern. A rapid membrane enzyme immunoassay for the simultaneous detection of C. diff glutamate dehydrogenase antigen and toxins A and B in a single reaction well was used to assess for C. diff. This test serves as a screen for the presence of C. diff and confirms the presence of toxigenic C. diff by detecting toxins A and B in fecal specimens. The rate (presence/absence) of pathogens was quantified for each dog during each session (pre/post). Paired samples t-tests were utilized to test for statistical significance (p < 0.05). The study involved 7 dogs of different breeds, including Golden Retrievers, Miniature Poodle, and Great Dane. The dogs were led through the department by their handler, and per protocol, did not visit the critically ill and suicidal patients. Upon arrival, all tests at baseline were negative for all 7 dogs. Following the dogs’ visits through the emergency department, all tests were negative for the 7 dogs on post-measure. Microbial analysis of the collected samples revealed that all 7 dogs carried commensal skin flora, even after very close contact with the patients who involved petting, hugging, and kissing the dogs. There was no growth of the pathogens of concern, namely E. coli, MRSA, C. diff, and Pseudomonas. Although there have been rare case reports of clinically significant transmission of microbial agents from domestic pets to humans, this study helps to demonstrate that pet therapy dogs do not pose a potential clinical harm to patients in the emergency department setting.

Capacitive Coupling Reduces Instrumentation-related Infection in Rabbit Spines: A Pilot Study

Postoperative spine infections cause considerable morbidity. Patients are subjected to long-term antibiotic regimens and may require further surgery. Delivery of electric current through instrumentation can detach biofilm, allowing better antibiotic penetration and assisting in eradicating infection. We asked (1) whether capacitive coupling treatment in combination with a single dose of antibiotics would reduce infection rates when compared with antibiotics alone in a rabbit spine infection model, (2) whether it would decrease the overall bacterial burden, and (3) whether there was a time-dependent response based on days treated with capacitive coupling. Thirty rabbits were subjected to a well-established spine infection model with a single dose of intravenously administered systemic ceftriaxone (20mg/kg of body weight) prophylaxis. Two noncontiguous rods were implanted inside dead space defects at L3 and L6 challenged with 10(6) colony-forming units of Staphylococcus aureus. Rabbits were randomly treated with a capacitive coupling or control device. Instrumentation and soft tissue bacterial growth were assessed after 7days. Sites treated with capacitive coupling showed a decrease in the incidence of positive culture: 36% versus 81% in the control group. We observed no difference in the soft tissue's infectious burden. Overall bacterial load was not decreased with capacitive coupling. Capacitive coupling in conjunction with antibiotics reduced the instrumentation-related infection rate compared with antibiotics alone. Capacitive coupling noninvasively delivers an alternating current that may detach biofilm from instrumentation. Treatment of infection may be successful without removal of instrumentation, allowing for improved stability and overall decreased morbidity.

Effect of a multipurpose disinfecting solution containing Polyquat and Alexidine on contamination of contact lens cases during use

Purpose: Silver-infused contact lenses (CLs) may provide benefits to CL wearers by reducing adherence of potential pathogens to CL surfaces; however, they have the potential to modify the normal ocular biota during wear. This study investigated the effect of silverinfused silicone hydrogel CLs on conjunctival flora over six months of daily wear (DW). Method: A prospective, randomised, doublemasked, contralateral study was conducted. Sixty subjects were randomly assigned to wear silverinfused (galyfilcon A with incorporated silver ions, test) and standard (galyfilcon A, control) silicone hydrogel CLs on a contralateral basis for six months of DW. Prior to assignment of the test and control CLs, all subjects were fitted with etafilcon A daily disposable CLs for a one week wearin period. Conjunctival flora were cultured at screening/pre-baseline (with subjects’ habitual CLs), baseline (after daily disposable wear) and four weeks, three and six months following commencement of test and control CL wear, using sterile calcium alginate swabs moistened with sterile unpreserved 0.9% saline. Results: There were no statistically significant differences between the conjunctivae of test and control eyes in incidence of positive cultures (p>0.05), culture classification grades (p>0.05), microorganism levels (p>0.05) or numbers of different types of microorganisms isolated (p>0.05). Wear of the test CLs did not promote fungal or yeast colonisation of the conjunctivae. The most frequently isolated microorganisms were Gram-positive bacteria considered to be part of the normal ocular flora. Conclusions: Wear of the silver-infused CLs did not result in any statistically or clinically significant alterations to the ocular biota over six months of DW.

Influence of care system and wearing modality on clinical performance of a single silicone hydrogel contact lens

Purpose: Silver-infused contact lenses (CLs) may provide benefits to CL wearers by reducing adherence of potential pathogens to CL surfaces; however, they have the potential to modify the normal ocular biota during wear. This study investigated the effect of silverinfused silicone hydrogel CLs on conjunctival flora over six months of daily wear (DW). Method: A prospective, randomised, doublemasked, contralateral study was conducted. Sixty subjects were randomly assigned to wear silverinfused (galyfilcon A with incorporated silver ions, test) and standard (galyfilcon A, control) silicone hydrogel CLs on a contralateral basis for six months of DW. Prior to assignment of the test and control CLs, all subjects were fitted with etafilcon A daily disposable CLs for a one week wearin period. Conjunctival flora were cultured at screening/pre-baseline (with subjects’ habitual CLs), baseline (after daily disposable wear) and four weeks, three and six months following commencement of test and control CL wear, using sterile calcium alginate swabs moistened with sterile unpreserved 0.9% saline. Results: There were no statistically significant differences between the conjunctivae of test and control eyes in incidence of positive cultures (p>0.05), culture classification grades (p>0.05), microorganism levels (p>0.05) or numbers of different types of microorganisms isolated (p>0.05). Wear of the test CLs did not promote fungal or yeast colonisation of the conjunctivae. The most frequently isolated microorganisms were Gram-positive bacteria considered to be part of the normal ocular flora. Conclusions: Wear of the silver-infused CLs did not result in any statistically or clinically significant alterations to the ocular biota over six months of DW.

The effect of silver-infused silicone hydrogel contact lenses on the ocular biota during daily wear

Purpose: Silver-infused contact lenses (CLs) may provide benefits to CL wearers by reducing adherence of potential pathogens to CL surfaces; however, they have the potential to modify the normal ocular biota during wear. This study investigated the effect of silverinfused silicone hydrogel CLs on conjunctival flora over six months of daily wear (DW). Method: A prospective, randomised, doublemasked, contralateral study was conducted. Sixty subjects were randomly assigned to wear silverinfused (galyfilcon A with incorporated silver ions, test) and standard (galyfilcon A, control) silicone hydrogel CLs on a contralateral basis for six months of DW. Prior to assignment of the test and control CLs, all subjects were fitted with etafilcon A daily disposable CLs for a one week wearin period. Conjunctival flora were cultured at screening/pre-baseline (with subjects’ habitual CLs), baseline (after daily disposable wear) and four weeks, three and six months following commencement of test and control CL wear, using sterile calcium alginate swabs moistened with sterile unpreserved 0.9% saline. Results: There were no statistically significant differences between the conjunctivae of test and control eyes in incidence of positive cultures (p>0.05), culture classification grades (p>0.05), microorganism levels (p>0.05) or numbers of different types of microorganisms isolated (p>0.05). Wear of the test CLs did not promote fungal or yeast colonisation of the conjunctivae. The most frequently isolated microorganisms were Gram-positive bacteria considered to be part of the normal ocular flora. Conclusions: Wear of the silver-infused CLs did not result in any statistically or clinically significant alterations to the ocular biota over six months of DW.

Differences in ocular physiological changes over time during daily silicone hydrogel contact lens wear with various care systems

Purpose: Silver-infused contact lenses (CLs) may provide benefits to CL wearers by reducing adherence of potential pathogens to CL surfaces; however, they have the potential to modify the normal ocular biota during wear. This study investigated the effect of silverinfused silicone hydrogel CLs on conjunctival flora over six months of daily wear (DW). Method: A prospective, randomised, doublemasked, contralateral study was conducted. Sixty subjects were randomly assigned to wear silverinfused (galyfilcon A with incorporated silver ions, test) and standard (galyfilcon A, control) silicone hydrogel CLs on a contralateral basis for six months of DW. Prior to assignment of the test and control CLs, all subjects were fitted with etafilcon A daily disposable CLs for a one week wearin period. Conjunctival flora were cultured at screening/pre-baseline (with subjects’ habitual CLs), baseline (after daily disposable wear) and four weeks, three and six months following commencement of test and control CL wear, using sterile calcium alginate swabs moistened with sterile unpreserved 0.9% saline. Results: There were no statistically significant differences between the conjunctivae of test and control eyes in incidence of positive cultures (p>0.05), culture classification grades (p>0.05), microorganism levels (p>0.05) or numbers of different types of microorganisms isolated (p>0.05). Wear of the test CLs did not promote fungal or yeast colonisation of the conjunctivae. The most frequently isolated microorganisms were Gram-positive bacteria considered to be part of the normal ocular flora. Conclusions: Wear of the silver-infused CLs did not result in any statistically or clinically significant alterations to the ocular biota over six months of DW.

Heparin-Induced Thrombocytopenia Antibody Is More Common in Patients with Active Bacterial Infections

Abstract 4678Heparin mobilizes and binds to platelet factor 4 (PF4), forming a heparin-PF4 complex on the platelet surface. Rarely, IgG antibodies recognize and bind to the immune complex, causing platelet activation and thrombin generation, resulting in heparin induced thrombocytopenia (HIT). There is evidence that PF4 has a role in antibacterial host defense and can concurrently prime the immune system with IgG antibodies that can cross-react with the heparin-PF4 complex (Krauel et al, Blood 2011). In the setting of a bacterial infection, the PF4 molecules interact with the bacterial cell wall and induce antibody production. These antibodies are able to recognize any bacteria coated in PF4, resulting in phagocytosis. In the setting of heparin, this antibody can cross react with the heparin-PF4 complex and result in HIT. In vitro studies suggest that E. coli, S. pneumo, and S. aureus coated in PF4 cross-react with human heparin induced anti-PF4/heparin antibodies.We have collected a database of patients being tested for HIT at our institution and performed a retrospective analysis of the incidence of bacterial infections. We hypothesize that patients who have a bacterial infection will be more likely to develop HIT due to anti-bacterial antibodies that cross-react with the heparin-PF4 complex. We collected culture data from 54 patients with positive HIT antibody by ELISA and 178 patients with negative HIT antibody. The incidence of positive cultures and active infections in described in table 1. In the HIT negative patients, 61/178 (34.3%) had positive cultures, compared to 28/54 (51.9%) in the HIT positive patients (p=0.0198). Given that there is data to support E. coli, S. pneumo, and S. aureus-induced antibody cross-reactivity, we performed a subgroup analysis of the incidence of these specific bacterial infection in HIT positive and negative patients (33.3% versus 19.7%, p=0.0357). There is a statistically significant difference noted in the active infections, subgroup analysis, as well presence of any positive cultures in the HIT positive patients as compared to the HIT negative patients.Table 1Colonized Infections (%)Active Infections (%)E. coli, S. pneumo, S. aureus (%)Any + culture (%)HIT negative (n=178)15 (8.4)61 (34.3)35 (19.7)66 (37.1)HIT positive (n=54)2 (3.7)28 (51.9)18 (33.3)29 (53.7)p value0.2420.01980.03570.0293This data supports that in the setting of active infection, particularly with E. coli, S. pneumo, and S. aureus, HIT antibody results should be carefully evaluated. Patients with positive cultures are likely to have thrombocytopenia from infection or sepsis, regardless of the presence of a HIT antibody. Thus, additional factors, such as the patient's 4T score and the presence of thrombosis should be considered prior to initiating treatment for HIT. Disclosures:No relevant conflicts of interest to declare.

Time-dependent Antibacterial Effects of the Self-Adjusting File Used with Two Sodium Hypochlorite Concentrations

Introduction This in vitro study evaluated the time-dependent ability of the self-adjusting file (SAF) used with either of two NaOCl concentrations to reduce bacterial populations in long oval root canals. Methods Oval-shaped canals from extracted teeth were infected with Enterococcus faecalis for 30 days and subjected to preparation with the SAF system using continuous irrigation with either 2.5% NaOCl (n = 11) or 6% NaOCl (n = 11). Bacteriological samples were taken before preparation (baseline) and after 2, 4, and 6 minutes of SAF operation. Results Intragroup quantitative analyses revealed that the SAF operating for 2, 4, or 6 minutes yielded a highly significant bacterial reduction when compared with counts at baseline ( P < .001) irrespective of the NaOCl concentration. No significant differences were found for intragroup analyses comparing the three time periods ( P > .05). Likewise, intergroup quantitative analysis showed no significant difference for the SAF with 2.5% NaOCl or 6% NaOCl during 2, 4, or 6 minutes ( P > .05). The incidence of positive cultures in the 2.5% NaOCl group was 6 of 11, 5 of 11, and 2 of 11 after 2, 4, and 6 minutes, respectively. Corresponding figures in the 6% NaOCl group were 4 of 11, 2 of 11, and 1 of 11. When all samples were gathered together, overall findings revealed that using the SAF for 6 minutes significantly reduced both the bacterial counts ( P = .02) and the incidence of positive cultures ( P = .04) when compared with 2 minutes. Conclusions Findings revealed that the SAF promoted a significant reduction in bacterial populations even after only 2 minutes regardless of the NaOCl concentration. The most impressive results were obtained after a 6-minute operation.

Bacteriology of postradiotherapy chronic rhinosinusitis in nasopharyngeal carcinoma patients and chronic rhinosinusitis

The purpose of this study was to investigate and compare the bacteriology of postradiotherapy chronic rhinosinusitis (postRT-CRS) and chronic rhinosinusitis (CRS) by evaluating the aspiration materials of the maxillary sinus of patients with postRT-CRS and patients with CRS. We collected the secretions of the maxillary sinus from 30 nasopharyngeal carcinoma patients with postRT-CRS and 30 patients with CRS for aerobe/facultative anaerobe bacteria culture. The most common isolates in the postRT-CRS group were Streptococcus viridans, Staphylococcus aureus and Haemophilus influenzae, while those in the CRS group were Haemophilus influenzae, Pseudomonas aeruginosa and Staphylococcus aureus. Isolated gram-positive coccus rate in postRT-CRS patients was significantly higher than in CRS patients (62.50% compared with 30.00%, respectively; P < 0.05), and isolated gram-negative bacilli rate in postRT-CRS patients was significantly lower than in CRS patients (31.25% compared with 70.00%, respectively; P < 0.05). However, the incidence of positive cultures was not significantly different between the postRT-CRS group and the CRS group (P > 0.05). This study found that there were some differences in bacteriology between postRT-CRS and CRS. Gram-positive coccus was the predominant aerobic/facultative anaerobe pathogenic bacterium in patients with postRT-CRS, and gram-negative bacilli was predominant in CRS patients.