Total Number Of Positive Cultures Research Articles

Successful Reduction of Blood Culture Contamination in an Emergency Department by Monitoring and Feedback

Background:Blood Culture (BC) contamination is a common problem in the Emergency Department (ED) and is associated with prolonged length of patient stay and excess costs.Objective:The study aimed to investigate the impact of monthly monitoring and feedback of BC results on contamination rates.Methods:Data from a previous study showed that the contamination rate in the ED consistently exceeded the recommended level. This triggered an ad hoc Quality Improvement team to develop and implement a corrective action plan. In 2017, BC contamination rates were reported to the ED on a monthly basis. In response to this, ED staff conducted intensified educational workshops, followed by private counselling and competency assessment of nurses who collected contaminated BCs.Results:A total of 12 educational workshops were conducted in February and March, 2017. The intervention resulted in >60% reduction in the contamination rate, from 8.6% baseline level to less than 3%. Of the 2660 BC sets drawn in 2017 from 1318 patients, 128 (4.8%) were contaminated, accounting for 39.5% of the total number of positive cultures. Sixty percent of the contaminated BCs grew Coagulase-negativeStaphylococcusspecies; other contaminants includedCorynebacteriumspp.,Micrococcusspp.,Propionibacteriumspp.,viridansStreptococcus, andNeisseriaspp.Conclusion:Continuous monitoring and feedback of contamination rates reduced BC contamination.

Antibiotic resistance profiles from isolated bacteria in outpatient infertility clinic in Greece

Aim: To investigate the prevalence of common aerobic gram positive and gram negative bacteria, Mycoplasma hominis, Ureaplasma urealyticum and Chlamydia trachomatis in symptomatic and asymptomatic Greek patients and to determine antibiotic resistance profiles. Methods: This retrospective study included a total of 316 adult men examined at the Assisted Reproduction Department of IASO- Obstetrics and Gynecology clinic in Athens, Greece. Sperm have been collected and proceed to culture and antibiotic sensitivity at the Central Laboratories following a standard protocol. Results: Twelve inappropriate out of 316 samples were excluded from the study. Out of the remaining 304 sperm samples 111 (37.5 %) were positive. Antibiotic sensitivity testing detected resistances to some commonly used antibiotics such as b-lactams and the quinolones. Ureaplasma urealyticum and Mycoplasma hominis were the most frequently isolated bacteria (45%), followed by Enterobacteriaceae (40%) and Enterococci 12.6%. The majority of 45 Enterobacteriaceae isolates, were Escherichia coli (31 strains/68%) corresponding to 27.9% of the total number of positive cultures. One infection to Chlamydia trachomatis was detected by an immunochromatic rapid test, one Candida sp, one Pseudomonas aeruginosa, two M. hominis and three Streptococcus group B. Escherichia coli were resistant to b lactams in about 38.7% due to b-lactamase, and 22.5%, 9.6%, 6.4%, were resistant to nitrofurantoin, sulfamethoxazole and ciprofloxacin respectively. Enterococci have shown resistance due to b-lactamase and PBP 5 alteration/hyperproduction. Ureaplasmas were resistant to the fluoroquinolones tested ciprofloxacin and ofloxacin, at 72.2% and 62.3% respectively. Conclusion: Carriage of bacteria in sperm is controversial for its contribution in sperm quality and fertility. In our IVF unit, we follow a protocol of isolation and antibiotic profiling of bacteria from sperm culture regardless of their concentration in sperm and giving the numbers/ml. This helps doctors to distinguish carriage or infection and to decide about potential therapy. Given the antibiotic resistances shown by this study, the importance of culture against empiric therapy in assisted reproduction patients is also clearly demonstrated.

Impact of Duration of Neutropenia and Lymphopenia on AML Patients Undergoing Induction Chemotherapy

Background:Various demographic, clinical and cytogenetic factors have been shown to affect the outcome of patients with acute myeloid leukemia (AML). Some of these risk factors are well-described with performance status and patient age being principal predictors of early death while cytogenetic and molecular factors allow stratification into prognostic categories. However, several critical factors have not been adequately assessed. Typically AML patients treated with standard induction chemotherapy will have cytopenias requiring intervention. Often the neutropenia is prolonged and results in neutropenic fevers and a high risk of infections. We hereby describe a single institution retrospective analysis at the University of Oklahoma Health Sciences Center (OUHSC) in which we evaluate the effect of duration of days with at risk absolute neutrophil (ANC) and absolute lymphocyte counts (ALC) and the occurrence of neutropenic fever on survival and response rates of AML patients.Methods:This is a retrospective chart review of AML adult patients who were diagnosed and treated at OUHSC between 2000 and 2014 and were undergoing initial induction chemotherapy. Outcomes of interest were overall survival (OS), event free survival (EFS: in case of relapse or death) and complete response (CR). Variables of interest wereneutropenic fever, and duration of decreased ANC and ALC counts (ANC<500, ANC<100, ALC<500, ALC<100). Institution policy did not allow granulocytes colony stimulating factors use because of the interference with bone marrow aspirate results. Nonetheless it was rarely used in few cases of septic shock, so this variable was not included in this analysis. Descriptive and bivariate analyses were conducted to evaluate the variables of interest and the outcomes.Models were used to assess the relationship between the variables of neutropenic fever, duration of decreased counts (ANC<500, ANC<100, ALC<500, ALC<100) and the outcome of interest after adjusting for age, race, gender, risk group andwhite blood count (WBC). Multivariable Cox proportional hazard models were used for OS and EFS and multivariable logistic regression models were used for CR. SAS 9.4 was used for all analyses. An alpha of 0.05 was used.Results:A total of 153 patients were analyzed. Mean age was 50 years, 35.7 % female, 64.3% male. Based on cytogenetics 16.9% were in favorable category, 28.6% in intermediate, 25.3% in unfavorable risk group, and 29.2% unknown. Mean number of weeks with ANC <500 was 3.58 (25 days), ANC <100 was 2.81 (20 days), ALC < 500 was 4.47 (31 days), ANC <100 was 3.24 (23 days). Incidence of neutropenic fever was 86.9%. Total number of positive cultures was 55.2%, of which 78.3% were bacterial, 25.3% fungal and 7.7% viral.After adjustment for age, race, gender, WBC and risk group, both neutropenic fever and duration during which ANC < 100 were associated with worse OS (p value <0.05) while duration of ANC< 500 was not significant (p value < 0.0576). When we considered EFS, the duration where ANC<500, ANC <100, and neutropenic fever occurrence were significant (p value <0.05).The hazard ratio of death is 3.15 for those with neutropenic fever compared to those without.With regard to CR, duration of ANC < 100 was significant (p value 0.0272). The duration of ALC <500 or <100 was not significant for OS nor EFS. Examining duration of neutropenia, for every week with ANC <500, there was a 9% higher hazard ratio of death after adjusting for other covariates.Conclusion:In this single-institution, retrospective study, we identified that the duration of neutropenia along with the presence of neutropenic fever during induction therapy adversely affected OS and EFS. Shorter duration of neutropenia significantly correlated with CR. Duration of days with ALC count <500 was not predictive of OS nor EFS. Larger studies are needed to examine the prognostic significance of neutropenia duration and its relationship to OS and CR. Neutropenia duration during induction chemotherapy may be an important risk factor in making decisions regarding future treatments including allogeneic transplant tolerability and aggressiveness of consolidation chemotherapy.It is important to look at this variable in more intensive induction regimens (using higher dose of cytarabine or adding a nucleoside analogue) as prolonged neutropenia may be a marker of poor general health rather than the induction regimen. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Infectious Complications In Patients with AL (Immunoglobulin Light Chain) Amyloidosis Undergoing Treatment with High-Dose Melphalan and Autologous Stem-Cell Transplantation (HDM/SCT)

Abstract 2041High dose melphalan and autologous stem cell transplantation (HDM/SCT) can lead to hematologic and organ responses and improved survival in selected patients with AL amyloidosis. Intrinsic and extrinsic risk factors for infections in these patients include functional hyposplenism, hypogammaglobulinemia, melphalan-induced neutropenia, mucositis, and nosocomial exposures. We performed a retrospective review of 493 patients with AL amyloidosis who underwent treatment with HDM/SCT at Boston Medical Center from August 1994 to August 2009. Patients received outpatient treatment from October 1996 onwards. The objectives of this study were to determine the rate of infections, identify infections leading to treatment-related mortality (TRM, defined as death within 100 days), and compare the impact of patient and treatment characteristics on rates of infection. Microbiologically documented infections after HDM/SCT were identified in 119 patients (24%, n=119/493). The median number of days to post- SCT infection was 8 days (range, 0–47). The mean number of days of body temperature more than 100.50 F (38° C) was 3 (95% CI 1.7–4.31). There were 48 deaths (10%) within 100 days of HDM/SCT. Among patients with documented infection, 25 had TRM (21%, n=25/119). Two hundred and forty five patients had febrile neutropenia. One hundred and forty seven of these had negative cultures. Therefore, the rate of culture negative febrile neutropenia was 60% (n=147/245). Identified pathogens included gram positive bacteria (51%), anaerobic bacteria (15%), gram negative bacteria (13%), fungi (8%) and viruses (6%). The majority of these organisms were identified in blood (50%), followed by respiratory secretions (20%) and stool (15%). Of the positive cultures, gram positive infections included staphylococci (29%), streptococci (10%), and enterococci (10%). C. difficile was the most commonly identified anaerobe, accounting for 11% of the total number of positive cultures. Gram negative bacterial infections included enterobacteriacae (8%) and pseudomonas (3%). Fungal infections included candida species (7%), aspergillus (4%) and pneumocystis (1%). Viral infections included herpes (3%), paramyxoviridae (3%) and cytomegalovirus (0.4%). In the unadjusted bivariate analyses, serum creatinine > 2 mg/dL was significantly associated with increased risk of post-HDM/SCT infections (38% versus 21%, p= 0.0007) with an odds ratio (OR) of 2.27 (95% CI 1.40–3.68). In addition, TRM was found to have a significant association with post-HDM/SCT infections (52% versus 21%, p = < 0.0001) with an OR of 3.82 (95% CI 2.01–7.26). The relative risk of TRM in a patient with documented infection was 3.42 (95% CI 2.02–5.79). In multivariate analyses, serum creatinine > 2 mg/dL remained significantly associated with post-SCT infection with an OR of 2.29 (95% CI 1.41–3.73). No significant association was found for age, gender, cardiac involvement, prior steroid therapy, dose of melphalan, time to neutrophil engraftment, number of organs involved in amyloidosis, or dose of infused CD34+ cells, both in unadjusted and adjusted analyses. In conclusion, serum creatinine >2 mg/dL is a risk factor for infections in patients with AL amyloidosis undergoing HDM/SCT. The relative risk of TRM in a patient with a documented infection was 3.34. A broad spectrum of infections, similar to those reported in other SCT patients, is seen in this population. Disclosures:No relevant conflicts of interest to declare.

Benzalkonium Chloride

The efficacy of benzalkonium chloride was evaluated as an irrigating solution for the eradication of Staphylococcus aureus from a contaminated orthopaedic wound. Thirty Sprague Dawley rats were randomized into two groups. A stainless steel wire was placed in a lumbar spinous process, and the wound was inoculated with 10(7) or 10(6) colony forming units of Staphylococcus aureus. The wound was irrigated with 1 L of normal saline or 0.1% benzalkonium chloride solution. The animals were sacrificed, and cultures were obtained. Rats inoculated with 10(7) colony forming units of Staphylococcus aureus and irrigated with benzalkonium chloride had a significant decrease in the total number of positive cultures, deep wound cultures, and stainless steel wire cultures. Rats inoculated with 10(6) colony forming units of Staphylococcus aureus and irrigated with benzalkonium chloride also had a significant decrease in the total number of positive cultures, deep wound cultures, and stainless steel wire cultures. In a parallel noninoculation study, histologic evaluation of tissues did not show toxicity in the rats irrigated with benzalkonium chloride. This study shows that benzalkonium chloride is more effective than normal saline as an irrigating agent for eradicating Staphylococcus aureus from a contaminated orthopaedic wound.

Anaerobic Bacteria in Clinical Infections

The findings of 275 cultures from routine clinical specimens obtained from lesions in different sites of body, during a period of 11 months, are presented. The clinical specimens were obtained from surgical wounds, abdominal infections, orthopaedic operations, biliary tract infections and pleuropulmonary infections. The total number of positive cultures including both aerobes and anaerobes was 203 out of 275 (73·8%). Of the 38 cultures positive for anaerobes, 29 (76·3%) grew both aerobic and anaerobic bacteria, while in nine (23·7%) cultures only anaerobes were found.A total of 42 strains of anaerobic bacteria were isolated. The majority of them were found in clinical specimens obtained from abdominal infections (62%), while a low percentage (3·6%) was found in specimens from orthopaedic operations.Strains belonging to the genusBacteroideswere the most frequently isolated anaerobes, accounting for 35·7% of the total, followed byClostridia28·5%,Peptostreptococci23·8% andPrevotella12%.

Cryogenic induced ocular HSV-1 reactivation is enhanced by an inhibitor of the lipoxygenase pathway

Reactivation of latent herpes simplex virus type 1 (HSV-1) has been shown to occur in response to localized inflammation. Prostaglandins and lipoxygenase products [eg. hydroxyeicosatetraenoic acids, (HETEs)] are associated with inflammation and, therefore, may play a role in HSV-1 infection and reactivation. In the rabbit cornea, alkali injury, cryogenic injury, and acute HSV-1 infection promote the synthesis of HETEs. Recently, a platelet activating factor antagonist, ginkgolide B (BN 52021) has been found to specifically inhibit the corneal synthesis of HETEs after alkali injury. If the induction of HETEs after injury is related to HSV reactivation and severity of infection, BN 52021 may alter HSV reactivation and the severity of infection by reducing the production of HETEs. To study the effect of BN 52021 on HSV-1 reactivation, cryogenic corneal lesions were produced in ten HSV-1 latently infected rabbits. Five rabbits were treated with topical and intravenous BN 52021 while the remaining five rabbits received topical artificial tears and intravenous saline. In the BN 52021 treated group, 90% (9/10) of the eyes and 53% (35/66) of the total ocular cultures were positive for HSV-1. In the control group, 60% (6/10) of the eyes, and 27% (18/66) of the ocular swabs were positive for HSV-1. The total number of positive cultures was significantly greater (p less than .05) in the BN 52021 treated rabbits. By increasing the number of positive HSV ocular cultures, BN 52021 appeared to act similarly to other inhibitors of arachidonic acid metabolism such as steroidal and nonsteroidal anti-inflammatory agents.

Evaluation of five cell types for the isolation of herpes simplex virus

Five cells were evaluated in a comparative analysis for sensitivity, specificity, and rapidity in detecting the presence of herpes simplex virus HSV-1 and HSV-2. Included in this study were human embryonic kidney (HEK), rabbit kidney (RK), MRC-5, mink lung (ML), and Microtus agrestis (UMMA). A total of 274 specimens from genital, throat, skin, or other sources that were submitted for HSV isolation were used in the study. The sensitivity of the different cells was assessed by the total number of positive cultures detected by all the cells under evaluation. At 48 hr, HEK and RK detected 80% of the positives, ML detected 79%, MRC-5 detected 73%, and UMMA detected 60%. All cells tested were satisfactory; however, the choice of which cell to use for isolation of HSV depends upon the needs of the specific laboratory.

The impact of urban community hospital surveillance for gonorrhoea on the infection rate and complications in the female. A progress report.

This study substantiates a previous report concerning the importance of the urban community hospital, particularly its emergency room, in the detection of gonorrhoea in women. Pelvic inflammatory disease (PID), a major complication of gonorrhoea in women, significantly declined during a nine-year surveillance and control programme in the Memphis-Shelby County area. This suggests that the programme may have prevented PID developing in women through the early detection and treatment of asymptomatic infections.

Rapid automated disgnosis of bacteremia by impedance detection

Lysis and filtration of blood culture specimens were combined with impedance detection of bacterial growth to facilitate the diagnosis of bacteremia. A blood lysis-filtration technique (Zierdt et al., 1976) was coupled to a simple, inexpensive automated detection system. The practical and technical aspects of the impedance detection system are discussed. This new blood culturing system was compared to a conventional system for 264 aerobic blood cultures. A 30-ml sample of the blood-broth mixture was withdrawn from the conventional aerobic blood culture bottle and processed in parallel. Excluding the isolation of the commonly recognized contaminants, the detection efficiency was 36% greater in the new system. A total of 53 blood cultures from 107 patients were positive by one or both methods. The new system detected 92% of the total number of positive cultures, compared with 56% detected by the routine method. The explanation of the differences is discussed.

Incidence, technique of isolation, and treatment of group B streptococci in obstetric patients

A prospective study was performed to determine the incidence of group B streptococci cultured from the cervix in a series of obstetric clinic patients at St. Margaret's Hospital. Cultures were taken during each trimester and planted to both a blood agar plate and a selective broth medium. Of a total of 812 cultures, 18 were positive, an over-all incidence of 2.2 per cent. During the first, second, and third trimesters, 2.2 per cent, 2.5 per cent, and 1.9 per cent of cultures were positive, respectively. Women with positive cultures were treated with a 10 day course of oral penicillin or a suitable alternative; four of 16 had persistent positive cultures at the end of the first treatment period, three of these four responded to a second course of antibiotics, and the remaining patient responded after a third treatment course. The total number of positive cultures by selective broth was 24, compared to nine in blood agar, indicating a 2.7-fold increase in pickup by the selective broth.

Mycoplasma recovery from the male genitourinary tract: voided urine versus the urethral swab.

A study of Mycoplasma recovery from the genitourinary tract was made on a group of 50 males attending a venereal disease clinic. The purpose of the investigation was to compare recovery rates of mycoplasma from two types of clinical specimens-the urethral swab and voided urine. The total number of positive cultures did not differ significantly when either the swab or urine was used; Mycoplasma hominis type 1 was the only taxonomic species isolated, either alone or mixed with T-strain mycoplasma. Recovery rates of the two types from both the swab and the urine did not differ significantly. Age did not relate to the presence of mycoplasma in the group studied.

Mycoplasma Recovery from the Male Genitourinary Tract: Voided Urine Versus the Urethral Swab

A study of Mycoplasma recovery from the genitourinary tract was made on a group of 50 males attending a venereal disease clinic. The purpose of the investigation was to compare recovery rates of mycoplasma from two types of clinical specimens-the urethral swab and voided urine. The total number of positive cultures did not differ significantly when either the swab or urine was used; Mycoplasma hominis type 1 was the only taxonomic species isolated, either alone or mixed with T-strain mycoplasma. Recovery rates of the two types from both the swab and the urine did not differ significantly. Age did not relate to the presence of mycoplasma in the group studied.