bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blood Cultures Positive for Coagulase-Negative Staphylococci: Antisepsis, Pseudobacteremia, and Therapy of Patients
Authors: Souvenir David , Anderson Donald E. , Palpant Samuel , Mroch Henry , Askin Susan , Anderson Jeffrey , Claridge Jerry , Eiland John , Malone Connie , Garrison Mark W. , Watson Patrice , Campbell Douglas M. 
Published: December 2019

ABSTRACT

A blood culture cohort study investigating issues related to isolation of coagulase-negative staphylococci (CoNS) and other skin microflora is reported. Data were collected over 12 weeks to determine the incidence of significant CoNS bacteremia versus that of pseudobacteremia (contaminants) and to evaluate drug therapy in patients with cultures positive for CoNS. In addition, the effectiveness of 0.2% chlorine peroxide as a bactericidal disinfectant was compared to that of 10% providone iodine. A total of 3,276 cultures of blood from 1,433 patients were evaluated in the study. Eighty-nine cultures were positive for skin flora, with 81 of 89 (91%) involving CoNS. The incidence of significant CoNS bacteremia was 20 of 81 (24.7%), that of indeterminate bacteremia was 10 of 81 (12.3%), and that of contamination was 59 of 81 (72.8%). The incidence of significant bacteremia involving CoNS was double the 10 to 12% rate based on previous estimations at our institutions. In tests with the two bactericidal disinfectants, 22 of 1,639 cultures (1.3%) in the chlorine peroxide group versus 37 of 1,637 (2.3%) in the providone iodine group were considered contaminated (
P
= 0.065). Rates of contamination for venipuncture versus catheter collection were not significantly different (
P
= 0.46). The overall contamination rate was 59 of 3,276 (1.8%), which is consistent with the lower end of published quality assurance benchmark standards. The low rate was believed to be due to the professional phlebotomy staff in our institutions. There was excellent agreement between retrospective analysis by reviewers, when formal criteria were used, and the attending physicians’ intuitive clinical impressions in the classification of significant bloodstream infections (100% agreement) or contamination (95% agreement). However, physicians still used antimicrobial agents to treat nearly one-half of the patients with contaminated blood cultures, with vancomycin being misused in 34% of patients. In addition, 10% of patients with significant bacteremia were treated with inappropriate agents. There were no significant adverse events or prolonged hospital stays due to the unnecessary use of vancomycin; however, the additional costs of treating patients whose cultures contained CoNS contaminants was estimated to be $1,000 per patient. Measures to limit the unnecessary use of vancomycin (and other agents) are important.
Extremely High Prevalence of Nasopharyngeal Carriage of Penicillin-Resistant
Streptococcus pneumoniae
among Children in Kaohsiung, Taiwan
Authors: Chiou Chen-Chia Christine , Liu Yung-Ching , Huang Tsi-Shu , Hwang Wen-Kuei , Wang Jen-Hsien , Lin Hsi-Hsun , Yen Muh-Yong , Hsieh Kai-Sheng 
Published: December 2019

ABSTRACT

Resistance (intermediate and high) to penicillin among
Streptococcus pneumoniae
strains is an emerging problem worldwide. From 1995 to 1997, isolates of
S. pneumoniae
not susceptible to penicillin were seen with increasing frequency from blood, cerebrospinal fluid, pleural fluid, and middle ear fluid from pediatric patients at the Veterans General Hospital-Kaohsiung. To determine the prevalence of carriage of these penicillin-nonsusceptible
S. pneumoniae
isolates, we obtained nasopharyngeal swab specimens from 2,905 children (ages, 2 months to 7 years) attending day-care centers or kindergartens or seen in our outpatient clinic.
S. pneumoniae
was isolated from 611 children, and 584 strains were available for analysis. The oxacillin disc test was used as a screening test to evaluate penicillin susceptibility. The MICs of 11 antibiotics (penicillin, cefaclor, cefuroxime, ceftriaxone, cefotaxime, imipenem, chloramphenicol, clarithromycin, rifampin, vancomycin, and teicoplanin) were determined by the E-test. Only 169 (29%) of the strains were susceptible to penicillin; 175 (30%) strains were intermediately resistant and 240 (41%) were highly resistant. The isolates also demonstrated high rates of resistance to other β-lactams (46% were resistant to cefaclor, 45% were resistant to cefuroxime, 45% were resistant to ceftriaxone, 31% were resistant to cefotaxime, and 46% were resistant to imipenem). The rate of resistance to macrolide antimicrobial agents was strikingly high; 95% of the isolates were not susceptible to clarithromycin. However, 97% were susceptible to rifampin and 100% were susceptible to the two glycopeptides (vancomycin and teicoplanin). While reports of penicillin-resistant
S. pneumoniae
increased worldwide through the 1980s, the high prevalence (71%) of resistance reported here is astonishing. Surveillance of nasopharyngeal swab specimen cultures may provide useful information on the prevalence of nonsusceptible strains causing invasive disease. Such information could be used to guide therapy of pneumococcal infections.
Survival ofAcinetobacter baumanniion Dry Surfaces: Comparison of Outbreak and Sporadic Isolates
Authors: Jawad A. , Seifert H. , Snelling A. M. , Heritage J. , Hawkey P. M. 
Published: December 2019

ABSTRACTAcinetobacterspp. are important nosocomial pathogens reported with increasing frequency in outbreaks of cross-infection during the past 2 decades. The majority of such outbreaks are caused byAcinetobacter baumannii. To investigate whether desiccation tolerance may be involved in the ability of certain strains ofA. baumanniito cause hospital outbreaks, a blind study was carried out with 39 epidemiologically well-characterized clinical isolates ofA. baumanniifor which survival times were determined under simulated hospital conditions. The survival times on glass coverslips of 22 strains isolated from eight well-defined hospital outbreaks in a German metropolitan area were compared with the survival times of 17 sporadic strains not involved in outbreaks but rather isolated from inpatients in the same geographic area. All sporadic isolates have been shown by pulsed-field gel electrophoresis to represent different strain types. There was no statistically significant difference between the survival times of sporadic strains ofA. baumanniiand outbreak strains (27.2 versus 26.5 days, respectively;P≤ 0.44) by the Wilcoxon-Mann-Whitney test. All investigatedA. baumanniistrains, irrespective of their areas of endemicity or epidemic occurrence, have the ability to survive for a long time on dry surfaces. Antimicrobial susceptibility testing showed thatA. baumanniioutbreak strains were significantly more resistant to various broad-spectrum antimicrobial agents than sporadic strains. Both desiccation tolerance and multidrug resistance may contribute to their maintenance in the hospital setting and may explain in part their propensity to cause prolonged outbreaks of nosocomial infection.
Epidemiological and Environmental Investigations of
Legionella pneumophila
Infection in Cattle and Case Report of Fatal Pneumonia in a Calf
Authors: Fabbi Massimo , Pastoris Maddalena Castellani , Scanziani Eugenio , Magnino Simone , Di Matteo Luigi 
Published: December 2019

ABSTRACT

A fatal pneumonia due to
Legionella pneumophila
was diagnosed in a young calf reared in a dairy herd located in northern Italy. Clinical symptoms consisted of watery diarrhea, hyperthermia, anorexia, and severe dyspnea. The pathological and histological findings were very similar to those observed in human legionellosis.
Legionella pneumophila
serogroup 1 (SG1) and SG10 were isolated from the calf’s lung, and
L. pneumophila
SG1 was isolated from the calf’s liver.
L. pneumophila
SG1 was also demonstrated in the lung tissue by immunofluorescence and immunohistochemical examinations. Nine of 10
L. pneumophila
SG1 isolates belonged to the Olda subtype, and 1 belonged to the Camperdown subtype. A very low prevalence of antibodies to
Legionella
was detected in cows and calves reared in the same herd. Cultures of aqueous sediment of an old electric water heater which supplied hot water for the feeding of the calves yielded
L. pneumophila
SG1. Four of the colonies tested belonged to the Olda subtype. Ten clinical and four environmental isolates were examined for the presence of plasmids. Nine of them were also examined by pulsed-field gel electrophoresis assay, and the same patterns were found for
L. pneumophila
SG1 Olda strains isolated from the calf and from the electric heater. This is the first report of a documented case of a naturally occurring
Legionella
pneumonia in an animal. Cattle probably act as accidental hosts for legionellae, much the same as humans.
Molecular Epidemiology of
Stenotrophomonas maltophilia
Isolated from Clinical Specimens from Patients with Cystic Fibrosis and Associated Environmental Samples
Authors: Denton Miles , Todd Neil J. , Kerr Kevin G. , Hawkey Peter M. , Littlewood James M. 
Published: December 2019

ABSTRACT

Stenotrophomonas maltophilia
was isolated from the respiratory tracts of 41 (25%) of 163 children attending our pediatric cystic fibrosis unit between September 1993 and December 1995. The extents of
S. maltophilia
contamination of environmental sites frequented by these patients were investigated with a selective medium incorporating vancomycin, imipenem, and amphotericin B. Eighty-two isolates of
S. maltophilia
were cultured from 67 different environmental sites sampled between January and July 1996. The organism was widespread in the home environment, with 20 (36%) and 25 (42%) of sampled sites positive in the homes of colonized and noncolonized patients, respectively. In the nosocomial setting, it was isolated from 18 (32%) sites in the hospital ward and from 4 (17%) sites in the outpatient clinic area. The most common sites of contamination were sink drains, faucets, and other items frequently in contact with water. All environmental and clinical isolates were genotyped with enterobacterial repetitive intergenic consensus sequences as primers. A total of 33 of the 41 patients were colonized with unique strains, and four pairs of patients shared strains. Further characterization by pulsed-field gel electrophoresis after digestion with
Xba
I found that there was no evidence of patient-to-patient transmission; however, there was some evidence that a small number of patients may have acquired the organism from the hospital environment. Resampling of environmental sites in the hospital ward in January 1997 revealed evidence of genetic drift, complicating the accurate determination of environmental sources for clinical strains. The source of the majority of
S. maltophilia
strains colonizing the respiratory tracts of these patients with cystic fibrosis remained uncertain but may have represented multiple, independent acquisitions from a variety of environmental sites both within and outside the hospital.
Evaluation of Intestinal Protozoan Morphology in Human Fecal Specimens Preserved in EcoFix: Comparison of Wheatley’s Trichrome Stain and EcoStain
Authors: Garcia Lynne S. , Shimizu Robyn Y. 
Published: December 2019

ABSTRACT

As a result of disposal problems related to the use of mercury compounds, many laboratories have switched from mercuric chloride-based Schaudinn’s and polyvinyl alcohol (PVA) stool preservatives to other, non-mercury-based preservatives. A comparison of organism recoveries and morphologies of the intestinal protozoa was undertaken with PVA containing the EcoFix zinc-based Schaudinn’s preservative (Meridian Diagnostics, Inc.); both Wheatley’s modification of Gomori’s trichrome stain (WT) and EcoStain (ES) were used to stain 51 human fecal specimens. Morphology, clarity of nuclear and cytoplasmic detail, overall color differences, and the ease or difficulty in detecting intestinal protozoa in fecal debris were assessed for the two permanent stained smears. Overall, organism morphology of the intestinal protozoa stained with WT and that of protozoa stained with ES were not equal in nuclear and cytoplasmic detail or range of color. However, the same organisms were identified in stained fecal smears with either WT or ES, with the exception of situations in which organism numbers were characterized as rare. Included were 67 protozoan challenges (number of organisms):
Entamoeba histolytica-Entamoeba dispar
(5),
Entamoeba coli
(9),
Entamoeba hartmanni
(6),
Endolimax nana
(12),
Iodamoeba bütschlii
(8),
Blastocystis hominis
(19),
Giardia lamblia
(6),
Dientamoeba fragilis
(2), yeast (2), and leukocytes (2). Five specimens were negative for parasites but contained fecal debris that was compared for morphologic detail and color range. The ES produces a more gray-green monotone with very little pink or red tone; contrast among the various colors is less than that seen with WT. Stain intensity for all organisms was acceptable, and there were no problems with stain deposition. The quality of the protozoan morphology with ES was often comparable to that with WT (36 of 67 [53.7%]) and, in some cases, better (24 of 67 [35.8%]). Organisms on the WT-stained smear exhibited better morphology in a few instances (4 of 67 [6%]), and in three instances, there were discrepant organism numbers.
Detection ofMycoplasma hyopneumoniaein Bronchoalveolar Lavage Fluids of Pigs by PCR
Authors: Baumeister A. Katrin , Runge Martin , Ganter Martin , Feenstra Anne A. , Delbeck Friedrich , Kirchhoff Helga 
Published: December 2019

ABSTRACTIn the present investigation we developed a method for the detection ofMycoplasma hyopneumoniaein bronchoalveolar lavage fluid (BALF) of pigs by PCR with a primer pair flanking a DNA fragment of 853 bp specific forM. hyopneumoniae. Several methods were tested to eliminate the amplification inhibitors present in BALFs. The best results were obtained by the extraction of the DNA from the BALFs. By the PCR performed with the extracted DNA, 102CFU ofM. hyopneumoniaecould be detected in 1 ml of BALF from specific-pathogen-free swine experimentally inoculated withM. hyopneumoniae. DNA from 11 other mycoplasma species and 17 cell-walled bacterial species colonizing the respiratory tracts of pigs was not amplified. In a field study BALFs from 40 pigs from farms with a history of chronic pneumonia were tested forM. hyopneumoniaeby cultivation and by PCR (i) with BALFs incubated in Friis medium and (ii) with DNA extracted from the BALFs. In addition, PCR was performed with postmortem lung washings from 19 of the 40 pigs, and immunofluorescence tests were carried out with sections of lungs from 18 of the 40 pigs.M. hyopneumoniaecould not be detected in 18 of the 40 pigs by any of the five methods tested. The remaining 22 pigs showed a positive reaction by the PCR with DNA extracted from the BALFs and variable positive reactions by the other tests. A complete correspondence could be observed between the immunofluorescence test result and the result of PCR with DNA. The investigation shows that the PCR with DNA extracted from BALFs is a suitable technique for the sensitive and specific in vivo detection ofM. hyopneumoniae.
Processing Respiratory Specimens with C
18
-Carboxypropylbetaine: Development of a Sediment Resuspension Buffer That Contains Lytic Enzymes To Reduce the Contamination Rate and Lecithin To Alleviate Toxicity
Authors: Thornton Charles G. , MacLellan Kerry M. , Brink Thomas L. , Wolfe David M. , Llorin Oscar J. , Passen Selvin 
Published: December 2019

ABSTRACT

The C
18
-carboxypropylbetaine (CB-18) procedure for processing respiratory specimens for the detection of mycobacteria was shown to provide significant increases in sensitivity by smear and culture. However, the procedure also produced increased contamination, a loss in liquid culture sensitivity, and a reduction in smear specificity. Because of these observations, the toxicity of CB-18 and the nature of the contamination were characterized. Preincubation in 1 mM CB-18 impacted viability in a time-dependent fashion, but the magnitude of the loss was species and isolate dependent.
Mycobacterium tuberculosis
isolates were the most susceptible, losing 20 to 30% of the CFU within 30 min and 30 to 60% after 3 h, whereas
Mycobacterium avium
and
Mycobacterium fortuitum
isolates were unaffected by CB-18. In liquid culture, when the concentration of CB-18 exceeded 5 μg/ml, there was an impact on growth characteristics for the most susceptible
M. tuberculosis
isolate. In contrast,
M. fortuitum
isolates were able to grow in 100 μg of CB-18 per ml. In liquid culture, the deleterious effects of CB-18 were enhanced in the presence of antibiotics, whereas growth on solid media was not similarly affected. Supplementation of the resuspension buffer with 0.15% lecithin alleviated toxicity. Initial attempts to modify the CB-18 procedure to control contamination incorporated acids or alkalis; however, losses in culture sensitivity occurred. Studies to identify these contaminants led to the development of a sediment resuspension buffer that contained lytic enzymes to combat contamination and lecithin to alleviate toxicity. This formulation included lysozyme, zymolyase, and
Cytophaga
and
Trichoderma
extracts and was seen to reduce contamination to acceptable levels (<5%).
Recombinant Hepatitis A Virus Antigen: Improved Production and Utility in Diagnostic Immunoassays
Authors: LaBrecque F. D. , LaBrecque D. R. , Klinzman D. , Perlman S. , Cederna J. B. , Winokur P. L. , Han J.-Q. , Stapleton J. T. 
Published: December 2019

ABSTRACT
Hepatitis A virus (HAV) immunoassays use cell culture-derived HAV antigen to detect HAV-specific antibodies. The current method of production of HAV antigen in tissue culture is time-consuming and expensive. We previously expressed the HAV open reading frame in recombinant vaccinia viruses (rV-ORF). The recombinant HAV polyprotein was accurately processed and was assembled into subviral particles. These particles were bound by HAV-neutralizing antibodies and were able to elicit antibodies which were detected by commercial immunoassays. The present investigation compared the production of HAV antigen by standard tissue culture methods to the production of HAV antigen with the recombinant vaccinia virus system. In addition, HAV and rV-ORF antigens were assessed for their utility in diagnostic immunoassays. Serum or plasma samples from HAV antibody-positive and antibody-negative individuals were evaluated by immunoassay that used either HAV or rV-ORF antigen. All samples (86 of 86) in which HAV antibody was detected by a commercial enzyme-linked immunosorbent assay (ELISA) also tested positive by the recombinant antigen-based immunoassay (VacRIA). Similarly, all samples (50 of 50) that were HAV antibody negative also tested negative by the VacRIA. The lower limit of detection of HAV antibody was similar among immunoassays with either HAV or rV-ORF antigen. Thus, in the population studied, the sensitivity and specificity of the VacRIA were equivalent to those of the commercial ELISA. Since production of recombinant antigen is faster and less expensive than production of traditional HAV antigen, the development of diagnostic HAV antibody tests with recombinant HAV antigen appears warranted.
Characterization of Serologically Nontypeable
Actinobacillus actinomycetemcomitans
Isolates
Authors: Paju Susanna , Saarela Maria , Alaluusua Satu , Fives-Taylor Paula , Asikainen Sirkka 
Published: December 2019

ABSTRACT

Our previous studies have shown that
Actinobacillus actinomycetemcomitans
isolates of a given arbitrarily primed PCR (AP-PCR) genotype belong to the same serotype (of serotypes a through e). In the present study we investigated whether the AP-PCR genotypes of nonserotypeable
A. actinomycetemcomitans
isolates match those of the serotypeable isolates. The isolates were additionally characterized by restriction analysis of the
apaH
PCR amplification products. The material included 75 nonserotypeable and 18 serotypeable
A. actinomycetemcomitans
isolates from 34 epidemiologically unrelated subjects. The serotypeable isolates were obtained from subjects who also harbored nonserotypeable isolates. Eight AP-PCR genotypes were distinguished among the isolates; six genotypes matched those detected in our previous studies, whereas two genotypes were new. Intraindividually, the
A. actinomycetemcomitans
isolates produced identical AP-PCR banding patterns, regardless of whether they were serotypeable or nonserotypeable, in 22 of 23 subjects participating with multiple isolates. AP-PCR genotype 3, corresponding to serotype c, was by far the most common among the nonserotypeable isolates (62% of subjects). Results obtained with the
apaH
restriction analysis confirmed the results obtained with AP-PCR for 31 of the 34 subjects. The results suggest that nonserotypeable
A. actinomycetemcomitans
isolates originate from serotypeable isolates, especially from serotype c isolates, and the likelihood of the existence of additional serotypes is small.
Rapid Diagnosis of Japanese Encephalitis by Using an Immunoglobulin M Dot Enzyme Immunoassay
Authors: Solomon Tom , Thao Le Thi Thu , Dung Nguyen Minh , Kneen Rachel , Hung Nguyen The , Nisalak Ananda , Vaughn David W. , Farrar Jeremy , Hien Tran Tinh , White Nicholas J. , Cardosa Mary Jane 
Published: December 2019

ABSTRACT
Japanese encephalitis (JE) occurs in rural settings in southern and eastern Asia, where diagnostic facilities are limited. For the diagnosis of JE virus (JEV) infection, we developed a nitrocellulose membrane-based immunoglobulin M (IgM) capture dot enzyme immunoassay (MAC DOT) that is rapid, simple to use, requires no specialized equipment, and can distinguish JEV from dengue infection. In a prospective field study in southern Vietnam, 155 cerebrospinal fluid (CSF) and 341 serum samples were collected from 111 children and 83 adults with suspected encephalitis. The JEV MAC DOT, performed on site, was scored visually from negative to strongly positive by two observers, and the results were compared subsequently with those of the standard IgM capture enzyme-linked immunosorbent assay. For the 179 patients with adequate specimens, the MAC DOT correctly identified 59 of 60 JEV-positive patients and 118 of 119 JEV-negative patients (sensitivity [95% confidence intervals], 98.3% [92.1 to 99.9%]; specificity, 99.2% [95.9 to 100.0%]; positive predictive value, 0.98; negative predictive value, 0.99). The MAC DOT also correctly identified three patients with dengue encephalopathy. Admission specimens were positive for 73% of JE patients. Interobserver agreement for MAC DOT diagnosis was excellent (kappa = 0.94). The JEV MAC DOT is a simple and reliable rapid diagnostic test for JE in rural hospitals.