Number Of Positive Cultures Research Articles

Hemolytic strains of Propionibacterium acnes do not demonstrate greater pathogenicity in periprosthetic shoulder infections

Hemolysis has been suggested as a feature conferring increased pathogenicity to certain Propionibacterium acnes strains in the setting of shoulder infection. The purpose of this study was to compare the virulence of hemolytic and nonhemolytic P acnes strains in patients undergoing revision shoulder arthroplasty. Thirty-nine patients with at least 1 positive culture growth for P acnes at the time of revision surgery were identified with P acnes isolates available for hemolysis testing. Patients were grouped into those with P acnes isolates positive (n = 20) and negative (n = 19) for hemolysis. The groups were retrospectively compared based on objective perioperative findings around the time of revision surgery and the postoperative clinical course, including the need for revision surgery. All cases were classified into categories of infection (definite infection, probable infection, and probable contaminant) based on objective perioperative criteria. The presence of hemolysis was not significantly associated with an increased likelihood of infection (P = .968). Hemolysis demonstrated a 75% sensitivity and 26% specificity for determining infection (definite infection and probable infection categories). The hemolytic and nonhemolytic groups showed no difference regarding preoperative serum erythrocyte sedimentation rate and/or C-reactive protein level (P = .70), number of positive cultures (P = .395), time to positive culture (P = .302), and presence of positive frozen section findings (P = .501). Postoperatively, clindamycin resistance, shoulder function, and the rate of reoperation were not significantly different between the hemolytic and nonhemolytic groups. The presence of hemolysis was not associated with increased pathogenicity in patients with P acnes-positive cultures following revision shoulder arthroplasty, when assessed by objective perioperative criteria and the postoperative clinical course.

Investigations of the prevalence and virulence of Candida albicans in periodontal and endodontic lesions in diabetic and normoglycemic patients.

Pulpal and periodontal tissues have similar microbiota that allows cross-contamination between the pulp and periodontal tissues. Objective The aim of this study was to investigate the prevalence of isolated Candida albicans from periodontal endodontic lesions in diabetic and normoglycemic patients, and the fungi's virulence in different atmospheric conditions.Material and Methods A case-control study was conducted on 15 patients with type 2 diabetes mellitus (G1) and 15 non-diabetics (G2) with periodontal endodontic lesions. Samples of root canals and periodontal pockets were plated on CHROMagar for later identification by polymerase chain reaction (PCR) and virulence test.Results C. albicans was identified in 79.2% and 20.8% of the 60 samples collected from diabetic and normoglycemic patients, respectively. Of the 30 samples collected from periodontal pockets, 13 showed a positive culture for C. albicans, with 77% belonging to G1 and 23% to G2. Of the 11 positive samples from root canals, 82% were from G1 and 18% from G2. Production of proteinase presented a precipitation zone Pz<0.63 of 100% in G1 and 72% in G2, in redox and negative (Pz=1), under anaerobic conditions in both groups. Hydrophobicity of the strains from G1 indicated 16.4% with low, 19.3% with moderate, and 64.3% with high hydrophobicity in redox. In G2, 42.2% had low, 39.8% had moderate, 18% had high hydrophobicity in redox. In anaerobic conditions, G1 showed 15.2% with low, 12.8% with moderate, and 72% with high hydrophobicity; in G2, 33.6% had low, 28.8% had moderate, and 37.6% had high hydrophobicity. There was statistical difference in the number of positive cultures between G1 and G2 (p<0.05) with predominance in G1. There was statistical difference for all virulence factors, except hemolysis (p=0.001).Conclusions Candida albicans was isolated more frequently and had higher virulence in diabetic patients.

Outbreak of Pseudomonas aeruginosa in a Neonatal Intensive Care Unit: Are Point-of-Use Filters Useful?

Pseudomonas aeruginosa, in intensive care units (ICUs), causes infections with high morbidity and mortality rates. Tap water outlets are often contaminated with P.aeruginosa and may represent a source of endemic infections in ICUs.The aim of this study was to explore the role of point-of-use (POU) filters in neo-natal intensive care unit (NICU) in reduc-ing P.aeruginosa colonizations/infections. Routine surveillance cultures, environ-mental cultures and samples from the hands of healthcare personnel, were taken and cultivated. P.aeruginosa isolates were identified according to standard proce-dures. For epidemiological purposes, anti-microbial susceptibility testing and pulse-field gel electrophoresis were performed. Data regarding use of antibiotics, disin-fectants, antiseptics, gloves and gowns from 2006 to 2012 were investigated.In March 2008, in the NICU of the Clini-cal Hospital Centre Zagreb (CHC Zagreb), we observed an increase in the total num-ber of pseudomonas infections compared to the previous months. This higher num-ber remained the same until October, de-spite rigorous infection control measures. Pseudomonas isolates were found in tap water, but not on the hands of healthcare workers. In that moment POU filters were introduced. The number of P.aeruginosa isolates in surveillance cultures dropped significantly.The number of positive cultures of P.aeruginosa in two consecutive periods (before and after installation of POU fil-ters) showed a statistically significant dif-ference.After the implementation of all infection control measures, we managed to stop the spread of pseudomonas colonization/infection. POU filters contributed only as one of these measures, resulting in a reduc-tion of chronically endemic P.aeruginosa infection/colonisation in the NICU.

Living Conditions as a Driving Factor in Persistent Methicillin-resistant Staphylococcus aureus Colonization Among HIV-infected Youth

Methicillin-resistant Staphylococcus aureus (MRSA) colonization has been linked to HIV-related sexual and social behaviors. MRSA risk factors may be different for HIV-infected children, adolescents and young adults. We investigated the association of MRSA colonization, persistent colonization and genotypes with potential risk factors among HIV-infected youth. For this case-control study, patients 24 years of age or younger attending 2 HIV reference centers were recruited from February to August 2012 and followed for 1 year. Nasal swabs were collected at enrollment and every 3 months. MRSA clones were characterized by staphylococcal chromosomal cassette mec typing, spa typing and multilocus sequence typing. We compared MRSA colonization and persistent colonization with patient demographic and clinical characteristics. Among 117 participants, MRSA colonization frequency (calculated for each collection based on the number of positive cultures per patient) was 12.8% at the first collection. The average MRSA colonization frequency was 10.4%. Our results showed 11.1% were persistent carriers (subjects with more than 1 positive culture in at least 3). Crowding was the only factor associated with MRSA colonization (P = 0.018). Persistent carriers had significantly higher (4.2 times) odds of living in a crowded household (95% confidence interval-1.1-16.2). We observed high genetic diversity among MRSA isolates, with t002/ST5 and t318/ST30 being the most frequent. MRSA colonization among HIV-infected youth is more closely related to living in a low-income or slum community than to HIV-related clinical factors. High genetic MRSA isolate diversity in our population suggests frequent transmission.

Impact of Elevator Mechanism Endoscope Culture and Quarantine on Availability and Patient Safety: A Multi-center Evaluation

Introduction: There has been increased recognition of the transmission of highly drug resistant strains of bacteria (Carbapenam Resistant Enterobacteriaceae or CRE) via duodenoscopes that have led to severe infection and even death in some patients. This risk is likely related to the elevator mechanism on duodenoscopes. The FDA has recommended one of four courses of action to address the risk of transmission, one of which is surveillance culturing of duodenoscopes with consideration of quarantine. We analyzed duodenoscope culture data from 6 low to moderate volume ERCP centers to evaluate the impact on patient safety and availability of duodenoscopes. Methods: Data was compiled from 6 ERCP centers to evaluate their mitigation strategy and assess its potential impact on patient safety and duodenoscope availability. The culture protocol, number of cultures and procedures performed per month, number of positive cultures, culture results and number of procedures delayed due to quarantine of duodenoscopes was collected and analyzed. Results: Five centers performed culture and quarantine of duodenoscopes after each procedure and another performed culture without quarantine once a month with intervening cultures at the endoscopist's discretion. The study period ranged from one to 6 months at each center (18 months total). Of a total 60 cultures performed across all centers, three were positive (5%) for low-concern organisms. One culture grew a high-concern organism (Klebsiella oxytoca), though this duodenoscope had malfunctioned and could not undergo proper reprocessing. Three procedures were delayed due to quarantine procedures. This occurred at low volume centers, which only had two total available duodenoscopes. Two cultures from duodenoscopes used in patients with a history of high concern organisms were performed at the endoscopists discretion at one center. Both of these cultures returned negative. Conclusion: Based on data from multiple low to moderate volume ERCP centers, culture of duodenoscopes did not yield any high concern organisms in properly reprocessed duodenoscopes and resulted in delaying interventions in several patients. This suggests that culture and quarantine would be low yield to these centers, have minimal impact on patient safety and could potentially delay therapeutic interventions for patients at centers with limited equipment.

血液培養における汚染率をめぐる用語の混乱

The blood culture contamination rate is often used to validate specimen-collection procedures. CUMITECH has set its optimal target to be 2% to 3%. However, the term "contamination rate" has been defined in many ways, limiting its generalizability. The definitions used in earlier studies can be divided into two categories; definitions based on clinical judgements, and those based on preset rules. According to each principle, the equation must be composed of a defined numerator and denominator. The problem with clinical definitions is that the decision is inevitably subjective, and the process is too cumbersome. Also, if the number of positive cultures is used as the denominator, the value would be equivalent to the positive predictive value, given that contamination is regarded as a "positive case." Thus, the value would not be useful for validating a procedure. On the other hand, when the preset algorithm was adopted, true infection would, to some degree, inevitably be classified as contamination. Also, if the algorithm adopted the number of blood culture sets as the denominator and contamination was defined as the identification of 1 or more specified organisms in only 1 of multiple sets of blood cultures, its theoretical maximum value would not be 100%. This is a problem because the value is a mixture of several numbers with different scales. In other words, whether the blood cultures are collected once, twice, or thrice or more a day would affect the result. The study cited by CUMITECH aimed to evaluate the equivalence between the clinical definition and the laboratory definition with preset rules, rather than to establish a benchmark for the contamination rate. It is undesirable for the number to be perceived as a benchmark. "A Guide to Blood Culture" (2013) by the Japanese Society for Clinical Microbiology introduced a calculation for the contamination rate, but the definition of the term "number of specimens" in the formula is ambiguous. In addition, the references cited in the guide do not concern contamination and do not even mention the definition of contamination rate. Thus, it is impossible to confirm the definition. In view of the weaknesses of these previous works, we defined the contamination rate as a benchmark for the validation of blood culture procedures as follows. [number of series in which 1 or more specified organisms (*) were identified in only 1 of multiple sets of blood cultures]/[total number of multiple sets of blood cultures in the series] *coagulase-negative staphylococci, Propionibacterium acnes, Micrococcus spp., Viridans-group streptococci, Corynebacterium spp., and Bacillus spp., but not B. anthracis.

751 Collagen IV-Pten Signaling Regulates Adult Enteric Neurogenesis In Vitro and In Vivo

G A A b st ra ct s model. Methods: Sepsis was induced in Swiss-OF1 mice by cecal ligation and puncture (CLP). Sham-operated animals served as controls. Mice received either GTS-21 8mg/kg i.p. (GTS) or vehicle (veh) 1h before the procedure, and subsequently once daily. Occurrence of ileus was confirmed by studying the geometric center (GC) of beads. At day 2 following CLP, mice were anesthetized and underwent a laparotomy, during which the colon was ligated and injected with 100μL of a 9% Evans blue (EB) solution. Mice were sacrificed 1h later via cardiac puncture and serum samples were analyzed for IL-6. Colons were rinsed and incubated for 24h in formamide to extract the EB from the colon wall. Whole blood and homogenized MLN were plated directly onto agar plates and cultured for 24h to quantify bacterial translocation. RT-PCR was performed on colons to determine cell adhesion molecules. Results: CLP resulted in a significant prolongation of GI transit times, while GTS was able to reverse this (GC: sham+veh 4.9±0.3, sham+GTS 4.2±0.3, CLP+veh 2.5±0.4*, CLP+GTS 4.3±0.4). IL-6 levels rose significantly after CLP and GTS was able to reduce these (sham+veh 2.6±0.5, sham+GTS 3.5±0.7, CLP+veh 243.6±54.9*, CLP+GTS 90.3±31.3 pg/ mL). Sepsis resulted in an increased colonic permeability, whereas GTS-21 was able to ameliorate the impaired colonic barrier (sham+veh 56.2±4.3, sham+GTS 43.7±3.8, CLP+veh 105.6±22.1*, CLP+GTS 49.5±6.9 μg EB/100mg colon). GTS appears to reduce the number of positive blood and MLN cultures following CLP-induced sepsis ( table 1). Sepsis caused a significant increase in the mRNA expression of all cell adhesion molecules ( table 2), with an additional increase in the mRNA expression of claudin-1 caused by GTS. Conclusion: CLP resulted in the occurrence of septic ileus with an increased colonic permeability and subsequent increased risk of bacterial translocation. GTS was able to ameliorate GI motility, suppress inflammation, normalize the permeability of the colonic wall, and decrease the number of positive cultures. The increase in mRNA expression of cell adhesion molecules following CLP presumably represents an attempted repair response. Targeting the α7nAChR appears to be an interesting therapeutic strategy in inflammation.

α-Defensin as a predictor of periprosthetic shoulder infection

Diagnosis of periprosthetic joint infection (PJI) in revision shoulder arthroplasty can be challenging because of the indolent nature of the common offending organisms. The purpose of this study was to evaluate the diagnostic utility of synovial fluid α-defensin levels in identifying PJI of the shoulder. Thirty patients evaluated for painful shoulder arthroplasty were prospectively enrolled and underwent revision surgery (n = 33 cases). Cases were categorized into infection (n = 11) and no-infection (n = 22) groups on the basis of preoperative and intraoperative findings. Synovial fluid was obtained from preoperative aspirations or intraoperative aspiration before arthrotomy. α-Defensin was tested by the Synovasure (CD Diagnostics, Wynnewood, PA, USA) test for joint infection. Synovial fluid was also obtained intraoperatively from a control group undergoing arthroscopic rotator cuff repair (n = 16) for baseline data on normal α-defensin levels in the shoulder. A receiver operating characteristic curve was used to determine the diagnostic utility of synovial fluid α-defensin. Synovial α-defensin had an area under the curve, sensitivity, specificity, and positive and negative likelihood ratios of 0.78, 63%, 95%, 12.1, and 0.38, respectively. There was a significant difference in α-defensin levels between the infection (median, 3.2 S/CO [signal to cutoff ratio]) and no-infection groups (median, 0.21 S/CO; P = .006). Synovial α-defensin was elevated in the presence of a culture positive for Propionibacterium acnes (median, 1.33 S/CO; P = .03) and showed moderate correlation with the number of positive cultures. Synovial fluid α-defensin was more effective than current diagnostic testing in predicting positive cultures and may be an effective adjunct in the workup of shoulder PJI.

Effects of onion juice on the normal flora of eyelids and conjunctiva in an animal model.

Background:Traditional medicine/complementary alternative medicine may suggest new ideas to modern medicine in order to face new challenges however these concepts should be acknowledged based on experimental studies.Objectives:We aimed to study the effects of onion (Allium cepa) juice on the normal flora of conjunctiva and eye lids, and to follow the histopathology changes of conjunctiva in an animal study.Materials and Methods:Twenty-four rabbits were randomly classified into three equal groups. Groups 1, 2 and 3 received fresh red onion juice, as an eye drop, into the right eye twice daily for; one week, one month, and two months, respectively. Microbiological sampling by sterile swabs was performed before and after the intervention. Cultural characteristics, including the growth rate and the kind of organisms, are reported. At the end of the study, pathological samples were collected from the inferior fornix.Results:After the intervention, the number of positive cultures in the samples, collected from both the conjunctiva and eyelid, had decreased. Group 3 demonstrated the lowest amount of growth after the administration of the onion juice and the bacterial isolation rates from each organism had decreased. All pathological samples revealed some degree of inflammation. There was no evidence of metaplasia or dysplasia. There was no significant difference between the growth rates of organisms in the experimental groups using statistical analysis.Conclusions:According to our experiment, onion has an inhibitory effect on the growth of normal eye flora; although the duration of onion juice instillation did not show any significant effect on the group results. Hence, this finding is an initiating point for further investigations into the antimicrobial properties of this herb to treat common eye infections, including conjunctivitis and blepharitis.

Comparison of 16S rRNA gene PCR and blood culture for diagnosis of neonatal sepsis

Septicemia is a common cause of morbidity and mortality among newborns in the developing world. However, accurate clinical diagnosis of neonatal sepsis is often difficult because symptoms and signs are often nonspecific. Blood culture has been the gold standard for confirmation of the diagnosis. However, the sensitivity is low and results are usually not promptly obtained. Therefore, the diagnosis of sepsis is often based on clinical signs in association with laboratory tests such as platelets count, immature/total neutrophils ratio (I/T), and a rise in C-reactive protein (CRP). Polymerase chain reaction (PCR) methods for the detection of neonatal sepsis represent new diagnostic tools for the early identification of pathogens. During a 4-month prospective study, 16S rRNA PCR was compared with conventional blood culture for the diagnosis of neonatal bacterial sepsis. In addition, the relationship between known risk factors, clinical signs, laboratory parameters, and the diagnosis of sepsis was considered. Sepsis was suspected in 706 infants from the intensive neonatal care unit. They all were included in the study. The number of positive cultures and positive PCR results were 95 (13.5%) and 123 (17.4%), respectively. Compared with blood culture, the diagnosis of bacterial sepsis by PCR revealed a 100.0% sensitivity, 95.4% specificity, 77.2% positive predictive value, and 100.0% negative predictive value. In this study, Apgar scores at 5 min, weight, icterus, irritability, feeding difficulties, gestational age (GA), premature rupture of membrane (PRM), platelets count, I/T, and a marked rise in CRP were important in establishing the diagnosis of sepsis in the newborn. In addition, weight, GA, PRM, irritability, duration of antibiotic usage, mortality rate, and number of purulent meningitis cases were significantly different between early-onset sepsis and late-onset sepsis. 16S rRNA PCR increased the sensitivity in detecting bacterial DNA in newborns with signs of sepsis, allowed a rapid detection of the pathogens, and led to shorter antibiotic courses. However, uncertainty about the bacterial cause of sepsis was not reduced by this method. 16S rRNA PCR needs to be further developed and improved. Blood culture is currently irreplaceable, since pure isolates are essential for antimicrobial drug susceptibility testing.

Clinical meaning of unexpected positive cultures (UPC) in revision shoulder arthroplasty

This study analyzed the prevalence and clinical meaning of unexpected positive cultures (UPCs) in revision shoulder arthroplasty for causes different than infection. Between 1976 and 2007, 107 consecutive patients with UPCs, no previous suspicion of infection, and fulfilling inclusion criteria were identified. Forty-five partial (PSA) and 62 total shoulder arthroplasties (TSA) with different preoperative diagnoses were reviewed. Cases were classified as true infections, possible infections, contaminants, and undetermined. Mean follow-up was 5.6 ± 5.3 years. The prevalence of UPC was 15%. Male sex was a risk factor for UPC. Results of preoperative blood tests and intraoperative pathology were negative in 94 and 97 cases, respectively. Most prevalent bacteria were Propionibacterium acnes (n = 68) and Staphylococcus epidermidis (n = 21). Fifty-three patients received treatment with antibiotics and 54 did not. In 11 patients, a postoperative arthroplasty infection during follow-up was diagnosed by culture and was produced by the same microorganism as the one isolated on the UPC (true infection). Risk factors for true infection vs contamination included revision of a TSA vs a PSA and the number of previous surgeries. Antibiotic use and number of positive cultures did not influence the rate of true infections. UPCs are a prevalent condition in revision shoulder arthroplasty for causes different than infection. In at least 25% of cases, UPC had no clinical relevance. In 10% of cases, a persistent infection was demonstrated.

Effectiveness of 1.25 % povidone–iodine combined with topical levofloxacin against conjunctival flora in intravitreal injection

To compare the effect of a reduced concentration (1.25 %) of povidone-iodine (PI) eye drops, combined with 0.5 % topical levofloxacin (LVFX), with that of the standard of care (5 % PI) on conjunctival flora before intravitreal injections (IVT). A prospective, randomized, single-blind clinical trial. One hundred eyes from 100 patients who underwent IVT were included. Eyes were randomly assigned to two groups and underwent different preparatory procedures before therapeutic IVT. LVFX drops were instilled three times every 5 min and then either 1.25 % PI drops were instilled three times every few minutes in group A or 5 % PI drops were instilled three times every few minutes in group B, the control. Conjunctival flora and the injection needles were collected for culture both before and after preparation. The number of positive cultures, the species isolated, and the minimum inhibitory concentrations (MIC) of the antibiotics were assessed. The pretreatment culture was positive for 45 eyes (86.5 %) in group A (n = 52) and for 37 eyes (77.1 %) in group B (n = 48). After the preparatory procedure, the cultures were positive for 25 eyes (48.1 %) in group A and for 27 eyes (56.3 %) in group B (P = 0.43). After preparation, the number of positive cultures decreased by 46.7 % in group A and by 33.4 % in group B (P = 0.48). No needle samples were contaminated in either group. The most common isolate in both groups after preparation for surgery was Propionibacterium acnes. Among the different antibiotics, vancomycin and oxacillin had the lowest MIC >90 for overall isolates. 1.25 % PI with LVFX is as effective as 5 % PI. P. acnes was the most common conjunctival flora detected. Vancomycin has been confirmed as the best choice for treating infectious endophthalmitis after IVT.

Cutaneous and Systemic Pathogenicity of a Clinical Isolate of Cladosporium sphaerospermum in a Murine Model

The pathogenicity of a clinical isolate of Cladosporium sphaerospermum was determined in a murine model. BALB/c mice were given two intraperitoneal injections of 150 mg/kg cyclophosphamide or normal saline on days 4 and 1 preinoculation, and were then challenged with 0.2 ml of C. sphaerospermum inoculum (2 × 10(7) CFU/ml) by topical application on an abrasive wound or by subcutaneous or intravenous injection. Histopathology and inverse fungal culture were performed on the skin lesions and viscera, and pulmonary fungal burden was also determined. Inoculated skin developed localized infections after dermabrasive or subcutaneous challenge in all mice, but the maximum area and number of positive cultures from skin lesions were higher for immunocompromised mice. In the intravenously inoculated mice, all immunocompetent animals survived for the 4-week period of the experiment, while 60% of immunocompromised animals died by 5 days postinoculation. The incidence of disseminated infection and the pulmonary fungal burden of immunosuppressed mice were higher than those of immunocompetent animals. Cutaneous and systemic infections can be established by subcutaneous and intravenous challenge with C. sphaerospermum in BALB/c mice, with the lungs being the most susceptible tissue in systemic infection.

Intermittent catheterization and recurrent urinary tract infection in spinal cord injury.

To study the association of recurrent symptomatic urinary tract infections (UTIs) with the long-term use of clean intermittent catheterization (CIC) for the management of neurogenic bladder in patients with spinal cord injury (SCI). Retrospective study of 61 SCI patients with neurogenic bladder managed by CIC. Subjects were selected from 210 SCI patients seen at the Yale Urology Medical Group between 2000 and 2010. Medical UTI prophylaxis (PRx) with oral antimicrobials or methenamine/ascorbic acid was used to identify patients with recurrent UTI. The number of positive cultures (≥10(3) cfu/mL) within a year prior to starting PRx was used to confirm the recurrence of UTI. Fifty-one male and 10 female subjects were managed with CIC. Forty-one (67%) subjects were placed on medical PRx for symptomatic recurrent UTI. Seventeen (28%) subjects had at least 3 positive cultures within the year prior to starting PRx. Fifteen of 20 (75%) subjects not on PRx had no complaints of UTI symptoms in the final year of follow-up. Recurrent symptomatic UTIs remain a major complication of long-term CIC in SCI patients. Although CIC is believed to have the fewest number of complications, many SCI patients managed with long-term CIC are started on medical PRx early in the course of management. Future studies are needed to determine the efficacy of routine UTI PRx in these patients as well as determine what factors influence why many patients on CIC experience frequent infections and others do not.

Catheter-Related Infection and Pathogens of Umbilical Venous Catheterization in a Neonatal Intensive Care Unit in China

We studied the incidence of umbilical venous catheterization (UVC)-related infection and pathogens in a neonatal intensive care unit (NICU) in China. Patients were grouped into <2000-g UVC or <2000-g non-UVC groups or ≥2001-g UVC or ≥2001-g non-UVC groups. Blood culture and umbilical root skin swab culture were taken following UVC insertion and extraction. UVCs were removed after 7 days and cultures of UVC tips were performed then. A total of 516 patients were enrolled. The incidence of UVC-related septicemia was 9.5%. The incidence of UVC-related septicemia per 1000 UVC days was 13.6. No significant difference was noted between <2000-g UVC and <2000-g non-UVC groups and between ≥2001-g UVC group and ≥2001-g non-UVC groups, in the number of positive blood cultures and skin cultures, the percentage of catheter-related septicemia, the incidence of catheter-related septicemia per 1000 catheter days, and the increase in the number of positive cultures between two skin cultures following UVC insertion and extraction. The predominant pathogen in all cultures was gram-positive pathogens. Coagulase-negative Staphylococcus was the most frequently noted pathogen. UVC did not increase the incidence of catheter-related infection in the NICU. It is necessary to consider local pathogen spectrum when choosing antibiotic therapy before specific culture results become available.

Experimental Pathogenicity of a Clinical Isolate of Trichosporon dermatis in a Murine Model

The pathogenicity of Trichosporon dermatis isolated from skin lesions of a patient has been examined in mice. Balb/c mice were treated with two intraperitoneal injections of 100 mg/kg cyclophosphamide on days 4 and 1 and one subcutaneous injection of 10 mg/kg dexamethasone on day 1 pre-inoculation, and then challenged with 0.2 ml T. dermatis inoculum (1 × 10(8) CFU/ml) by topical application on an abrasive wound in the dermabrasive group and by hypodermic injection in the subcutaneous group. In the intravenous group, 0.2 ml of high (1 × 10(8) CFU/ml) or low (1 × 10(7 )CFU/ml) inoculum was injected into the tail vein. Histopathology and inverse fungal culture were performed on the skin lesion and viscera, and renal fungal burden was also determined. Inoculated sites developed localized infections after dermabrasive and subcutaneous challenge in all mice, but the maximum area of skin lesions, and number of positive cultures from the lesions, were higher for immunocompromised mice. In the intravenous group, all immunocompetent animals survived during the four-week period, whereas 100 and 70% of immunocompromised animals died by 3 and 5 days in the high and low-inoculum groups, respectively. The incidence of disseminated infection and the renal fungal burden of immunocompromised mice were higher than those of immunocompetent mice. Our results demonstrate that subcutaneous and intravenous injection of T. dermatis can successfully establish cutaneous and systemic infection models in immunocompromised mice, with the kidney and lung being most susceptible.

Application of 10% Povidone Iodine Reduces Conjunctival Bacterial Contamination Rate in Patients Undergoing Cataract Surgery

To determine the efficacy of 10% povidone iodine (PVI) drops given before cataract extraction in addition to routine irrigation of the conjunctival sac with 1% PVI. This prospective, randomized, single-center study at the Department of Ophthalmology, Ludwig-Maximilians-University, Munich, includes 263 eyes of 242 patients undergoing cataract surgery. Patients were randomized to receive 3 drops of 10% PVI into the conjunctival sac (study group) or no PVI drops (control group). All patients underwent periorbital disinfection with 10% PVI followed by irrigation of the conjunctiva with 10 mL of 1% PVI. Specimens were obtained prior to the application of PVI, after antibiotic administration (T1), after irrigation with PVI but before surgery (T2), and at the conclusion of surgery (T3). After PVI disinfection, the number of positive cultures was significantly reduced in all groups (p<0.0001) from 69%-93% at T1 to 1%-16% at T3. In outpatients, the study group showed significantly fewer positive cultures at the conclusion of surgery compared to the control group (4% vs 16%; p=0.03). Also in inpatients significant fewer positive cultures were found in the study group compared to the control group at T2 (12% vs 28%; p=0.03) and at T3 (1% vs 10%; p=0.03). Three additional drops of 10% PVI prior to surgery provided additional benefit by reducing the conjunctival bacterial contamination rate even in the setting of preoperative irrigation of the conjunctiva with 1% PVI.

Isolation of Mycobacterium avium complex from the "24-hour bath"

The "24-HOUR BATH" is an apparatus which circulates the bath water, keeps it clean and warm, and makes it possible to take a bath at any time during the day or night. It consists of apparatus for cleaning (sponge or mesh filter and filter material), heating (ceramic heater), and sterilizing (UV lamp). Recently, three cases of skin disease due to M. avium infection in private homes, in which "24-HOUR BATH" water was suspected to be the source of infection, have been reported. We attempted to isolate M. avium complex from the water (32 specimens), sponge filter (29 specimens), and filter material (32 specimens) of the "24-HOUR BATH". One hundred-ml samples of bath water, and 50-ml samples of rinse from a sponge filter or filter material were centrifuged at 3000 rpm for 20 min. Sediment was suspended in distilled water and a smear was prepared, and then digested and decontaminated with 2% sodium hydroxide. The processed specimens were cultured on 2% Ogawa medium containing ofloxacin (1 microgram/ml) and ethambutol (2.5 micrograms/ml) for 8 weeks at 37 degrees C. Positive smears were 3 (9.4%), 25 (86.2%) and 25 (78.1%) specimens from the water, sponge and filter material, respectively. A few bacterial clumps were observed, especially in the sponge specimens. The number of positive culture was 5 (15.6%), 24 (82.8%) and 25 (78.1%) from the water, sponge and filter material, respectively. Among them the number of Runyon's Group III-positive cultures was 5 (100%), 22 (91.7%) and 20 (80%) in the water, sponge, and filter material specimens, respectively. In most cases, cultures were positive for both the sponge and filter material specimens. All of the Group III mycobacteria were smooth, grew at 28, 37, 42, and 45 degrees C, negative for niacin, nitrate reductase, semiquantitative catalase, urease and Tween80 hydrolysis, and positive for 68 degrees C catalase. All of the strains reacted with M. avium complex AccuProbe and M. avium AccuProbe, but none of the strains reacted with M. intracellulare AccuProbe. Therefore, all the Group III isolates were identified as M. avium by the culture, biochemical and genetical characteristics.

Utility of Routine Culture for Tuberculosis from Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration in a Tuberculosis Endemic Country

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a technique developed to allow mediastinal staging of lung cancer and also to evaluate intrathoracic lymphadenopathy. In a tuberculosis-endemic area, tuberculosis should be considered as an etiology of mediastinal lymphadenopathy. The aim of this study was to investigate the utility of the routine culture for tuberculosis from specimens of EBUS-TBNA. Results: A total of 135 lymph node aspiration and 118 core biopsy specimens were included in this analysis. We confirmed the malignancy in 62 (72.9%), tuberculosis in 7 (8.1%), sarcoidosis in 7 (8.1%), asperogillosis in 2 (2.3%) and pneumoconiosis in 2 (2.3%) patients. One lung cancer patient had pulmonary tuberculosis coincidentally and 5 patients had unknown lymphadenopathy. The number of positive culture for Mycobacterium tuberculsosis by EBUS-TBNA is 2 (1.5%) from 135 lymph node aspiration specimens and 2 (1.7%) from 118 core biopsy specimens. Out of eight patients confirmed with tuberculosis, only one patient had positive mycobacterial culture of aspiration specimen from EBUS-TBNA without histopathologic diagnosis. Conclusion: These results propose that routine culture for tuberculosis from EBUS-TBNA may not provide additional information for the diagnosis of coincident tuberculous lymphad enitis. However, if there is any possibility of tuberculous lymphadenopathy or pulmonary tuberculosis, it should be considered to perform EBUS-TBNA in patients who have negative sputum AFB smears or no sputum production.

1391 How Useful are Blood Cultures on PICU?

Objectives: To determine the current practice of obtaining blood cultures sent from PICU. Methods: Retrospective study of all blood cultures sent from patients in one calendar month (January 2009). Results: A total of 140 blood cultures were sent from 34 patients over 89 screening episodes. Only 22% of screening episodes achieved the minimum requirement of cultures of blood, urine and ET aspirates. Neither clinical parameters nor infective indices showed reliable correlation with positive blood cultures. 23 (16%) of blood cultures were positive whilst 9 samples were attributed to probable contaminants. A single patient (with Candidaemia) accounted for 10 positive samples. Blood cultures were obtained from different sites including peripheral (36), arterial (54), central (50). The number of positive cultures were equivalent from each of these sites. Of the patients screened after admission 60 were already receiving IV antibiotics. Conclusions: Blood cultures were commonly performed and demonstrated a low overall yield perhaps as a result of the criteria used for screening. Several areas of practice warrant improvement including obtaining a complete screen more often and implementing measures to reduce the contamination of peripheral samples (no touch technique).A prospective study would be needed to determine the criteria for screening more accurately. Furthermore, there is a need for more reliable indices of infection which may also reduce the use of antimicrobials.