bluuebunny/crossref_metadata_2025 huggingface dataset:
Incidence of
Toxoplasma gondii
Infection in 35,940 Pregnant Women in Norway and Pregnancy Outcome for Infected Women
Authors: Jenum Pål A. , Stray-Pedersen Babill , Melby Kjetil K. , Kapperud Georg , Whitelaw Andrew , Eskild Anne , Eng Jan
Published: December 2019

From 1992 to 1994 a screening program for detection of specific
Toxoplasma gondii
antibodies involving 35,940 pregnant women was conducted in Norway. For women with serological evidence of primary
T. gondii
infection, amniocentesis and antiparasitic treatment were offered. The amniotic fluid was examined for
T. gondii
by PCR and mouse inoculation to detect fetal infection. Infants of infected mothers had clinical and serological follow-up for at least 1 year to detect congenital infection. Of the women 10.9% were infected before the onset of pregnancy. Forty-seven women (0.17% among previously noninfected women) showed evidence of primary infection during pregnancy. The highest incidence was detected (i) among foreign women (0.60%), (ii) in the capital city of Oslo (0.46%), and (iii) in the first trimester (0.29%). Congenital infection was detected in 11 infants, giving a transmission rate of 23% overall, 13% in the first trimester, 29% in the second, and 50% in the third. During the 1-year follow-up period only one infant, born to an untreated mother, was found to be clinically affected (unilateral chorioretinitis and loss of vision). At the beginning of pregnancy 0.6% of the previously uninfected women were falsely identified as positive by the Platelia Toxo-IgM test, the percentage increasing to 1.3% at the end of pregnancy. Of the women infected prior to pregnancy 6.8% had persisting specific immunoglobulin M (IgM). A positive specific-IgM result had a low predictive value for identifying primary
T. gondii
infection.
Hepatitis C in a Hemodialysis Unit: Molecular Evidence for Nosocomial Transmission
Authors: Le Pogam S. , Le Chapois D. , Christen R. , Dubois F. , Barin F. , Goudeau A.
Published: December 2019

This study reports four cases of transmission of the rare hepatitis C virus genotype 4 which occurred in a hemodialysis unit and originated from a single source of infection. Phylogenetic analyses performed with the NS5b domain showed that all four patients with secondary infections were infected with virus strains very similar to that of the index patient. Cross infections probably resulted from breaches in safety precautions and lack of dialysis machine sterilization.
Isolation of
Enterobacter intermedium
from the Gallbladder of a Patient with Cholecystitis
Authors: O’Hara Caroline Mohr , Steward Christine D. , Wright Joan L. , Tenover Fred C. , Miller J. Michael
Published: December 2019

We describe the isolation and identification of
Enterobacter intermedium
from the gallbladder of a patient with cholecystitis. There have been only four documented isolations of this organism from humans; it normally occurs in surface water and unpolluted soils. The identification was initially made by a MicroScan Walk/Away system with a Neg Combo 18 conventional identification-susceptibility panel. The organism is susceptible to the aminoglycosides and imipenem but resistant to the cephalosporins and ciprofloxacin.
Confirmation of Nosocomial Transmission of Hepatitis C Virus by Phylogenetic Analysis of the NS5-B Region
Authors: Norder Heléne , Bergström Åsa , Uhnoo Ingrid , Aldén Jöran , Weiss Lars , Czajkowski Jan , Magnius Lars
Published: December 2019

Four hepatitis C virus transmission chains at three dialysis units were disclosed by limited sequencing; three of these were disclosed by analysis of the NS5-B region of the genome. Dialysis on the same shift as that during which infected patients were dialyzed was the common factor for seven patients in two chains. Two nurses exposed to needle sticks and their sources of infection constituted two other chains. The strains of three chains belonged to subtype 1a and formed clusters with an intrachain variability of 0 to 6 nucleotides compared to 8 to 37 nucleotides for unrelated strains within this subtype. The clusters were supported by bootstrap values ranging from 89 to 100%.
Hepatitis C Virus RNA in Dried Serum Spotted onto Filter Paper Is Stable at Room Temperature
Authors: Abe Kenji , Konomi Nami
Published: December 2019

To overcome the instability of viral RNA, we carried out hepatitis C virus (HCV) RNA detection in dried serum spotted onto filter paper. The spotted serum samples were stored at room temperature and then processed for PCR assay at intervals of 1, 2, 3, and 4 weeks. The results showed that serum HCV RNA is stable in a dried condition, as it was detectable in spotted serum samples stored for 4 weeks at room temperature. Furthermore, although the HCV RNA titer showed an ∼10-fold reduction in virus yield in dried serum stored at room temperature for 4 weeks, the PCR results of frozen serum samples and dried serum samples matched completely. This storage method facilitates transport and analysis by nucleic acid amplification techniques even when freezing conditions are not available.
Colony Variation in
Staphylococcus lugdunensis
Authors: Leung Michael J. , Nuttall Nichalas , Pryce Todd M. , Coombs Geoffrey W. , Pearman John W.
Published: December 2019

Staphylococcus lugdunensis
is being increasingly reported as a pathogen with an outcome resembling that of
S. aureus
rather than coagulase-negative staphylococci. Recent local isolates exhibited colonial variation that delayed identification and interpretation of clinical significance. Until now previous descriptions have not emphasized colonial variation as an important identifying characteristic of
S. lugdunensis
.
Molecular Fingerprinting of
Mycobacterium tuberculosis
Isolates Obtained in Havana, Cuba, by IS
6110
Restriction Fragment Length Polymorphism Analysis and by the Double-Repetitive-Element PCR Method
Authors: Montoro Ernesto , Valdivia José , Leão Sylvia Cardoso
Published: December 2019

Mycobacterium tuberculosis
sputum isolates from 38 patients, obtained in the first 6 months of 1997 in Havana, Cuba, were characterized by IS
6110
restriction fragment length polymorphism (RFLP) analysis and the double-repetitive-element PCR (DRE-PCR) method. Among 41 strains from 38 patients, 24 and 25 unique patterns, and 5 and 4 cluster patterns, were found by the RFLP and DRE-PCR methods, respectively. Patients within two of these clusters were found to be epidemiologically related, while no relation was observed in patients in the other clusters. The DRE-PCR method is rapid, and it was as discriminating as IS
6110
RFLP analysis in identifying an epidemiological association. Its simplicity makes the technique accessible for subtyping of
M. tuberculosis
strains in laboratories not equipped to perform RFLP analysis.
Unreliability of Disc Diffusion Test for Screening for Reduced Penicillin Susceptibility in
Neisseria meningitidis
Authors: Block Colin , Davidson Yehudit , Keller Nathan
Published: December 2019

The 2-U penicillin and 1-μg oxacillin discs proposed for screening meningococci for susceptibility to penicillin were evaluated by using MICs measured by the E test. The discs yielded unacceptably high frequencies of misclassification of susceptibility category and should be abandoned in favor of MIC estimations. An agreed breakpoint for reduced penicillin susceptibility in meningococci is needed for the E test.
Macroscopic Agglutination Test for Rapid Diagnosis of Human Leptospirosis
Authors: Brandão Angela P. , Camargo Eide D. , da Silva Emilson D. , Silva Marcos V. , Abrão Rui V.
Published: December 2019

A commercially available slide agglutination test (SAT) for the diagnosis of human leptospirosis was evaluated by comparing it to an immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) and to the microscopic agglutination test (MAT). For all 108 patients, leptospirosis was diagnosed on the basis of a fourfold or greater increase in titer by MAT (seroconversion), and all but 1 of 245 controls were MAT negative (titers, <1:100). Both SAT and the IgM ELISA failed to detect one case of infection (sensitivity, 99%). Only 3 of 145 blood donors and none of the 100 patients with other illnesses were SAT positive (specificity, 99%). The overall results were similar for the three tests; however, SAT and ELISA were statistically more sensitive as initial screening tests. For 22% of the patients, the diagnosis of leptospirosis was made earlier by SAT than by MAT. SAT detected 27 (44%) of 62 MAT-negative patients with the first serum sample. ELISA and SAT had very similar results. Follow-up of patients for 1 year after the onset of symptoms showed a decreasing rate of positivity by SAT from the third month on. The rate of positivity by ELISA decreased more slowly, to about 67% by the end of the study. By MAT all patients were persistently reactive. SAT and ELISA seem to be convenient methods for the rapid and early screening for leptospirosis and could replace the less sensitive MAT. ELISA gives less subjective results than SAT and provides information on IgM kinetics, but it can be performed only by the more sophisticated laboratories. SAT is inexpensive, can be performed more quickly and more easily than ELISA, and could be used by the less well equipped laboratories.
Molecular Analysis of Glycopeptide-Resistant
Enterococcus faecium
Isolates Collected from Michigan Hospitals over a 6-Year Period
Authors: Thal LeeAnn , Donabedian Susan , Robinson-Dunn Barbara , Chow Joseph W. , Dembry Louise , Clewell Don B. , Alshab Drew , Zervos Marcus J.
Published: December 2019

The purpose of this study was to evaluate the molecular relatedness of clinical isolates of glycopeptide-resistant
Enterococcus faecium
isolates collected from hospitals in Michigan. A total of 379 isolates used in this study were all vancomycin-resistant
E. faecium
isolates collected from 28 hospitals and three extended-care facilities over a 6-year period from 1991 to 1996. For the 379 isolates, there were 73 pulsed-field gel electrophoresis (PFGE) strain types. Within strain types, there were as many as six restriction fragment differences. Most isolates (70%) belonged to six strain types, which were designated M1 (36%), M2 (3%), M3 (18%), M4 (6%), M10 (4%), and M11 (3%). PFGE strain M1 was cultured from 135 patients in 13 hospitals during the period 1993 to 1996. Strain type M2 was cultured from 11 patients in two hospitals during the period 1991 to 1992 and was not observed after 1992. Strain type M3 was cultured from 70 patients in 10 hospitals during the period of 1994 to 1996. Both M4 and M10 were cultured from 23 patients in three hospitals and from 15 patients in two hospitals, respectively, during 1995 to 1996. M11 was cultured from 13 patients in four hospitals during 1996. A total of 23 of 28 hospitals had evidence of clonal dissemination of some isolates. Plasmid content and hybridization analysis done on 103 isolates from one hospital and two affiliated extended-care facilities indicated that the strains contained from one to eight plasmids. Mating experiments indicated transfer of vancomycin resistance from 94 of these isolates into plasmid-free
E. faecium
GE-1 at transfer frequencies of <10
−9
to 10
−4
. Gentamicin resistance and erythromycin resistance were cotransferred at various frequencies. A probe for the
vanA
gene hybridized to the plasmids of 23 isolates and to the chromosomes of 72 isolates. A probe for the
vanB
gene hybridized to the chromosomes of 8 isolates. The results of this study suggest inter- and intrahospital dissemination of vancomycin-resistant
E. faecium
strains over a 6-year period in southeastern Michigan. The majority of isolates studied belonged to the same few PFGE strains, indicating that clonal dissemination was responsible for most of the spread of resistance that occurred.
Characterization of La Crosse Virus RNA in Autopsied Central Nervous System Tissues
Authors: Chandler Laura J. , Borucki Monica K. , Dobie Dawn K. , Wasieloski Leonard P. , Thompson Wayne H. , Gundersen Cameron B. , Case Kay , Beaty Barry J.
Published: December 2019

A reverse transcription-PCR (RT-PCR) technique was used to detect La Crosse (LAC) virus RNA in the central nervous system (CNS) tissues of two patients who died of LAC encephalitis in 1960 and 1978. Viral RNA was readily detected by RT-PCR although the tissues had been stored frozen for up to 37 years. LAC virus was detected in the cerebral cortex but not in other CNS tissues. RT-PCR allowed detection of replicative forms of the virus, indicating that the virus was actively replicating in the specific CNS tissues. The small (S) RNA segments of the viruses from the CNS samples were demonstrated to be genetically similar by single-strand conformation polymorphism analyses. These S RNA segments were then sequenced; only two base changes were demonstrated between the 1960 and the 1978 samples, suggesting that LAC virus is genetically stable in areas of endemicity. The RT-PCR analyses of analyte directly from CNS tissues allows study of the virus without passage in cell culture.
Genetic Heterogeneity ofBorrelia burgdorferiSensu Lato inIxodes ricinusTicks Collected in Belgium
Authors: Misonne Marie-Christine , Van Impe Georges , Hoet Philippe P.
Published: December 2019

Borrelia burgdorferisensu lato (s.l.), the etiological agent of Lyme disease, is transmitted by the bite ofIxodes ricinus. Four hundred eighty-nine ticks, collected in four locations of a region of southern Belgium where Lyme disease is endemic, were examined for the presence of the spirochete. In a PCR test with primers that recognize a chromosomal gene of all strains, 23% of the ticks were found to be infected. The speciesB. burgdorferis.l. comprises at least three pathogenic genomospecies,B. burgdorferisensu stricto (s.s.),Borrelia garinii, andBorrelia afzelii, which could be distinguished in PCR tests with species-specific primers that correspond to distinct plasmid sequences.B. gariniiwas most prevalent (53% of infected ticks), followed byB. burgdorferis.s. (38%) andB. afzelii(9%). Of the infected ticks, 40% were infected with a single species, 40% were infected with two species, and 5% were infected with all three species. For 15% of the ticks, the infecting species could not be identified. No difference in rates of prevalence was observed among the four locations, which had similar ground covers, even though they belonged to distinct biogeographic regions. A greater heterogeneity of spirochetal DNA in ticks than in cultured reference DNA was suggested by a comparison of the results of PCRs with two different sets of species-specific primer sequences.
Development and Evaluation of an Epstein-Barr Virus (EBV) Immunoglobulin M Enzyme-Linked Immunosorbent Assay Based on the 18-Kilodalton Matrix Protein for Diagnosis of Primary EBV Infection
Authors: Chan K. H. , Luo R. X. , Chen H. L. , Ng M. H. , Seto W. H. , Peiris J. S. M.
Published: December 2019

A new immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) based on the recombinant Epstein-Barr virus (EBV) matrix protein was developed. Compared to indirect immunofluorescence for the detection of IgM antibody to the EBV capsid antigen on clinical specimens, the sensitivity and specificity of the new IgM ELISA were 96 and 96%, respectively.
Comparison of Costs of Strategies for Measuring Levels of Human Immunodeficiency Virus Type 1 RNA in Plasma by Using Amplicor and Ultra Direct Assays
Authors: Raboud J. M. , Seminari E. , Rae S. L. , Harrigan P. R. , Hogg R. S. , Conway B. , Sherlock C. , Schechter M. T. , O’Shaughnessy M. V. , Montaner J. S. G.
Published: December 2019

The costs of four algorithms for monitoring plasma human immunodeficiency virus type 1 RNA were compared. For patients with strong virologic responses, the use of Ultra Direct exclusively was the cheapest strategy. For patients with weak virologic responses, small savings could be obtained by using Amplicor and retesting only samples with values below 500 copies/ml with Ultra Direct.
Evaluation of the Nuclisens HIV-1 QT Assay for Quantitation of Human Immunodeficiency Virus Type 1 RNA Levels in Plasma
Authors: Segondy Michel , Ly Thoai-Duong , Lapeyre Martine , Montes Brigitte
Published: December 2019

Nuclisens HIV-1 QT is a new version of the NASBA HIV-1 QT assay for quantitation of human immunodeficiency virus type 1 (HIV-1) RNA in plasma. The specificity of this assay was 100% in one laboratory and 99%—with nonrepeatability of the initial false positive—in another. The test was linear between 2.0 and 6.0 log RNA copies per ml. According to the input HIV-1 RNA concentration, accuracy varied from −0.11 to +0.10 log RNA copy per ml and precision varied from 0.66 to 0.14 log RNA copy per ml. Reproducibility decreased when the HIV-1 RNA level was near the lower limit of quantitation of the test. HIV-1 RNA could be quantitated by Nuclisens HIV-1 QT in 36% (laboratory 1) and 24% (laboratory 2) of clinical samples with HIV-1 RNA levels lower than the lower limit of quantitation by NASBA HIV-1 QT. Nuclisens HIV-1 QT was not suitable for measurement of RNA from clade G and group O HIV-1 strains.
Seroprevalence of
Ehrlichia canis
and of Canine Granulocytic Ehrlichia Infection in Dogs in Switzerland
Authors: Pusterla Nicola , Pusterla Jeannine Berger , Deplazes Peter , Wolfensberger Celestine , Müller Werner , Hörauf Angelika , Reusch Claudia , Lutz Hans
Published: December 2019

Serum samples from 996 dogs in Switzerland were examined for antibodies to
Ehrlichia canis
and to the agent causing canine granulocytic ehrlichiosis (CGE). Ehrlichiosis, borreliosis, and systemic illness not associated with ticks were suspected in 75, 122, and 157 of these dogs, respectively. The remainder of the serum samples were obtained from clinically healthy dogs which resided north (
n
= 235) or south (
n
= 407) of the Alps. The serum samples were tested by an indirect immunofluorescence technique for antibodies to the two agents incriminated,
E. canis
and
Ehrlichia phagocytophila
, a surrogate marker of the agent of CGE. Twenty-two of 996 (2.2%) serum samples had antibodies to
E. canis
and were distributed as follows: 20 of 75 (26.7%) samples from dogs suspected of having ehrlichiosis, 1 of 122 (0.8%) from dogs suspected of having borreliosis, and 1 of 407 (0.2%) from healthy dogs which resided south of the Alps. Of the 75 (7.5%) serum samples that had antibodies to
E. phagocytophila
, significantly more samples were from ill dogs than from healthy dogs. Among the sera from healthy dogs, antibodies to
E. phagocytophila
were significantly more prevalent in the north. Because seropositive dogs had a history of travel outside Switzerland and because
Rhipicephalus sanguineus
is found exclusively south of the Alps, it was presumed that, in contrast to the agent of CGE,
E. canis
is not indigenous to Switzerland.
Comparative Evaluation of Chlamydiazyme, PACE 2, and AMP-CT Assays for Detection of
Chlamydia trachomatis
in Endocervical Specimens
Authors: Wylie John L. , Moses Stephen , Babcock Ryan , Jolly Ann , Giercke Sandra , Hammond Greg
Published: December 2019

We conducted a comparative evaluation of the Chlamydiazyme (Abbott Laboratories), PACE 2 (Gen-Probe), and AMP-CT (Gen-Probe) assays for the detection of
Chlamydia trachomatis
in endocervical samples. Specimens from 787 females were included in the study. The sensitivities of the PACE 2 and Chlamydiazyme assays in comparison to the results of the AMP-CT assay were 79.3 and 63.4%, respectively. The specificities of the Chlamydiazyme and PACE 2 assays were 100%. All of the positive specimens detected in this study were positive by the AMP-CT assay. On the basis of the final results of the comparison, the prevalence of
C. trachomatis
in the population was 10.4%. Retesting of specimens whose results were in the intermediate zone by the PACE 2 assay by a probe competition assay identified some additional true-positive specimens. Amplification assay testing of such specimens did not significantly increase the yield. The majority of specimens which tested positive by the AMP-CT assay only were not in the intermediate zone by the PACE 2 assay. We were unable to identify demographic or clinical factors which could predict those individuals who tested positive by amplified tests but not by nonamplified tests. The Gen-Probe PACE 2 assay proved to be superior to the Chlamydiazyme assay for the screening and diagnosis of
C. trachomatis
infections in female endocervical specimens.
Tick-Borne Relapsing Fever in British Columbia, Canada: First Isolation of
Borrelia hermsii
Authors: Banerjee Satyendra N. , Banerjee Maya , Fernando Keerthi , Burgdorfer Willy , Schwan Tom G.
Published: December 2019

The spirochete that causes tick-borne relapsing fever,
Borrelia hermsii
, was isolated in pure culture during 1995 and 1996 from three acutely ill human patients infected in southern British Columbia, Canada. The geographic area of exposure is a known focus of this disease dating back to 1930 when the first case was recognized in a human. Analyses of plasmid DNA, protein profiles, and reactivity with a species-specific monoclonal antibody identified the new isolates of spirochetes as
B. hermsii
, all of which were most similar to an isolate of this spirochete from northern California described previously. These are the first reported isolates of
B. hermsii
from Canada.
Identification of Three Major Clones of Multiply Antibiotic-Resistant
Streptococcus pneumoniae
in Taiwanese Hospitals by Multilocus Sequence Typing
Authors: Shi Zhi-Yuan , Enright Mark C. , Wilkinson Paul , Griffiths David , Spratt Brian G.
Published: December 2019

In this paper we demonstrate the advantages of a new molecular typing procedure, multilocus sequence typing, for the unambiguous characterization of penicillin-resistant pneumococci. The sequences of ∼450-bp fragments of seven housekeeping genes were determined for 74 penicillin-resistant Taiwanese isolates of
Streptococcus pneumoniae
(MIC of penicillin > 0.5 μg/ml). The combination of alleles at the seven loci defined an allelic profile for each strain, and a dendrogram, based on the pairwise mismatches in allelic profiles, grouped 86% of the isolates into one of three penicillin-resistant clones for which the MICs of penicillin were 1 to 2 μg/ml. Isolates within each clone had identical alleles at all seven loci or differed at only a single locus, and the fingerprints of their
pbp1A
,
pbp2B
, and
pbp2X
genes were uniform. Isolates of the Taiwan-19F clone and the Taiwan-23F clone were resistant to penicillin, tetracycline, and erythromycin but were susceptible to chloramphenicol. A second serotype 23F clone and serotype 19F variants of this clone were resistant to penicillin, tetracycline, chloramphenicol, and, in some cases, erythromycin. Comparisons of the allelic profiles of the three major clones with those of reference isolates of the known penicillin-resistant clones showed that the Taiwan-19F and Taiwan-23F clones were previously undescribed, whereas the second serotype 23F clone was indistinguishable from the Spanish multidrug-resistant serotype 23F clone. Single isolates of the Spanish penicillin-resistant serotype 9V clone and the Spanish multidrug-resistant serotype 6B clone were also identified in the collection.
Prenatal Diagnosis of Congenital Cytomegalovirus Infection
Authors: Lazzarotto T. , Guerra B. , Spezzacatena P. , Varani S. , Gabrielli L. , Pradelli P. , Rumpianesi F. , Banzi C. , Bovicelli L. , Landini M. P.
Published: December 2019

We report here the results of a study on the prenatal diagnosis of congenital cytomegalovirus (CMV) infection. The study was carried out by both PCR and virus isolation from amniotic fluid (AF) for 82 pregnant women at risk of transmitting CMV for the detection of (i) seroconversion to CMV immunoglobulin G (IgG) positivity during the first trimester of pregnancy, (ii) symptomatic CMV infection in the mother during the first trimester of pregnancy or intrauterine growth retardation detected by ultrasound or abnormal ultrasonographic findings suggestive of fetal infections, and (iii) seropositivity for CMV-specific IgM. For 50 women, fetal blood (FB) was also obtained and tests for antigenemia and PCR were performed. The results indicate that AF is better than FB for the prenatal diagnosis of CMV infection. PCR with AF has a sensitivity (SNS) of 100%, a specificity (SPE) of 83.3%, a positive predictive value (PPV) of 40%, and a negative predictive value (NPV) of 100%; rapid virus isolation with the same material has an SNS of 50%, an SPE of 100%, a PPV of 100%, and an NPV of 94.7%. Fewer than 10% of the women positive for IgM by enzyme immunoassay (EIA) had a congenitally infected fetus or newborn infant. When EIA IgM positivity was confirmed by Western blotting (WB) and the WB profile was considered, the percent transmission detected among women with an “at-risk” profile was higher than that observed among IgM-positive women and was the same as that among women who seroconverted during the first trimester of pregnancy (transmission rates of 29 and 25%, respectively).
Shiga Toxin-Producing
Escherichia coli
in Finland from 1990 through 1997: Prevalence and Characteristics of Isolates
Authors: Keskimäki Markku , Saari Marjut , Heiskanen Tarja , Siitonen Anja
Published: December 2019

During the past 10 years Shiga toxin-producing
Escherichia coli
(STEC) has emerged as one of the most important causes of food-borne infections in industrialized countries. In Finland, with a population of 5.1 million, however, only four STEC O157:H7 infections were identified from 1990 through 1995; the occurrence of non-O157 STEC infections was unknown. In 1996, we established a national prospective study to determine the prevalence of STEC serotypes in feces of Finns with bloody diarrhea. During this enhanced 1-year study period eight sporadic cases of STEC infection were found; of them, only two were indigenously acquired O157:H7 infections. In 1997, O157 infections increased dramatically, with O157 strains causing 51 of all 61 STEC infections. Altogether 14 non-O157:H7 STEC strains were found in Finland in the 1990s: O26:H11 (four strains), O26:HNM (HNM indicates nonmotile), O2:H29, O91:H21, O91:H40, O101:HNM, O107:H27, O157:HNM, O165:H25, OX3:H21, and Rough:H49. All O157:H7 and O26:H11 isolates produced enterohemolysin, but seven of the other STEC strains did not. Most (
n
= 63) of the 71 STEC strains isolated carried the
stx
2
gene only, five carried the
stx
1
gene only, and three carried both genes. The
eaeA
gene was detected in all other isolates except five non-O157 strains. There were seven distinct pulsed-field gel electrophoresis (PFGE) genotypes among 57 O157 strains and three distinct PFGE types among four O26:H11 strains. The main PFGE type was found among 65% of all O157 isolates.
Phenotypic and Genotypic Characterization of Nosocomial
Staphylococcus aureus
Isolates from Trauma Patients
Authors: Na’was T. , Hawwari A. , Hendrix E. , Hebden J. , Edelman R. , Martin M. , Campbell W. , Naso R. , Schwalbe R. , Fattom A. I.
Published: December 2019

Staphylococcus aureus
is a major cause of nosocomial infections. During the period from March 1992 to March 1994, the patients admitted to the intensive care unit of the University of Maryland Shock Trauma Center were monitored for the development of
S. aureus
infections. Among the 776 patients eligible for the study, 60 (7.7%) patients developed 65 incidents of nosocomial
S. aureus
infections. Of the clinical isolates, 43.1% possessed a polysaccharide type 5 capsule, 44.6% possessed a type 8 capsule, and the remaining 12.3% had capsules that were not typed by the type 5 or type 8 antibodies. Six antibiogram types were noted among the infection-related isolates, with the majority of the types being resistant only to penicillin and ampicillin. It was noted that the majority of cases of pneumonia were caused by relatively susceptible strains, while resistant strains were isolated from patients with bacteremia and other infections. Only 16 (6.3%) of the isolates were found to be methicillin-resistant
S. aureus
(MRSA). DNA fingerprinting by pulsed-field gel electrophoresis showed 36 different patterns, with characteristic patterns being found for MRSA strains and the strains with different capsular types. Clonal relationships were established, and the origins of the infection-related isolates in each patient were determined. We conclude that (i) nosocomial infection-related isolates from the shock trauma patients did not belong to a single clone, although the predominance of a methicillin-resistant genotype was noted, (ii) most infection-related
S. aureus
isolates were relatively susceptible to antibiotics, but a MRSA strain was endemic, and (iii) for practical purposes, the combination of the results of capsular and antibiogram typing can be used as a useful epidemiological marker.
Evaluation of PCR Primers for Early Diagnosis of Cytomegalovirus Infection following Liver Transplantation
Authors: Mendez Julio C. , Espy Mark J. , Smith Thomas F. , Wilson Jennie A. , Paya Carlos V.
Published: December 2019

The availability of microbiologic methods that detect early replication of cytomegalovirus (CMV) posttransplantation will enhance the process of initiating preemptive antiviral therapy prior to the appearance of CMV disease. Using PCR techniques we sought to determine which region of the CMV genome present in peripheral blood leukocytes (PBLs) or serum provides the highest sensitivity for the detection of CMV posttransplantation. Blood samples were prospectively collected weekly for at least 8 weeks from a cohort of 21 consecutive liver transplant recipients not receiving anti-CMV prophylaxis. Results of PCR assays were correlated with recovery of CMV in cell cultures and histopathological findings from biopsy specimens of infected organs to assess clinical symptomatic infection. Of 148 specimens, primer pairs directed to the
Hin
dIII-X fragment region of CMV detected target DNA with a 94% sensitivity, compared to an 87% sensitivity with primer pairs directed to
Eco
RI fragment D, 32% sensitivity with primer pairs directed to the immediate-early antigen 1 gene (IEA1 gene), and 20% sensitivity with primer pairs directed to the major immediate-early (MIE) gene. The performance characteristics in terms of the sensitivity of primers for amplifying CMV DNA associated with symptomatic infection ranged from 100% (
Hin
dIII-X) to 20% (MIE gene); however, specificity was inversely related (
Hin
dIII-X, 45%; MIE gene, 91%) to primers directed to these gene targets. When
Hin
dIII-X and
Eco
RI-D primer sets were used, CMV DNA from PBLs was a more sensitive target than CMV DNA from serum for the early detection of symptomatic CMV infection (17 versus 12 days). Importantly, CMV DNA was not detected in five patients with no evidence of this viral infection. In conclusion, primers directed to the
Hin
dIII-X fragment region were the most optimal for the early detection of CMV DNA in PBLs and sera from symptomatic liver transplant recipients.
Failure of Quality Control Measures To Prevent Reporting of False Resistance to Imipenem, Resulting in a Pseudo-Outbreak of Imipenem-Resistant
Pseudomonas aeruginosa
Authors: Carmeli Yehuda , Eichelberger Karen , Soja Don , Dakos Joanna , Venkataraman Lata , DeGirolami Paola , Samore Matthew
Published: December 2019

False results showing an outbreak of
Pseudomonas aeruginosa
with resistance to imipenem were traced to a defective lot of microdilution MIC testing panels. These panels contained two- to threefold lower concentrations of imipenem than expected and resulted in artifactual two- to fourfold increases in MICs of imipenem. The quality-control MIC results for
Pseudomonas aeruginosa
ATCC 27853 were 4 μg/ml, the highest value within the range recommended by the National Committee for Clinical Laboratory Standards. We recommend that this value be considered out of the quality-control range.
Standardized BACTEC Method To Measure Clarithromycin Susceptibility of
Mycobacterium genavense
Authors: Carlson La Donna C. , Wallis Carolyn K. , Coyle Marie B.
Published: December 2019

A standardized clarithromycin susceptibility test for
Mycobacterium genavense
is reported. The BACTEC radiometric broth dilution test method recommended for
Mycobacterium avium
complex was modified to develop a reliable and reproducible procedure. Test development involved optimization of medium pH and inoculum densities for antibiotic vials as well as growth control vials. MIC control organisms included
Mycobacterium simiae
,
Mycobacterium avium
, and
Mycobacterium xenopi
. Growth control vials required two to three inoculum dilutions, which varied for each species. Clarithromycin MICs and MBCs for 12 isolates and 1 colonial variant of
M. genavense
ranged from ≤0.06 to 0.25 μg/ml.
Cellular Fatty Acid Composition, Soluble-Protein Profile, and Antimicrobial Resistance Pattern of
Eubacterium lentum
Authors: Mosca Adriana , Summanen Paula , Finegold Sydney M. , De Michele Giampiero , Miragliotta Giuseppe
Published: December 2019

Phenotypic heterogeneity among isolates of
Eubacterium lentum
has been recognized for many years. To better delineate their taxonomic relatedness, 29 clinical isolates of
E. lentum
were examined for soluble-protein content, cellular fatty acid profile, and antimicrobial resistance pattern in order to ascertain whether differences in these characteristics could be correlated with differences in biochemical activities. Among 29 isolates we could identify 6 that were different from all the others. These strains were coccobacilli with translucent colonies; they were catalase and H
2
S negative, not fluorescent under UV light, and susceptible to beta-lactam drugs; growth was not stimulated by arginine; and fatty acid analysis revealed the presence of straight-chain fatty acids. The remainder of the strains, including the type species, were pleomorphic bacilli with speckled colonies and were catalase and H
2
S positive; all but two were fluorescent under UV light; they were resistant to beta-lactam antibiotics; growth was greatly stimulated by arginine; and they demonstrated saturated branched-chain fatty acids. Our data suggest that
E. lentum
can be further differentiated into different types.
Biochemical and Pathogenic Properties of
Shewanella alga
and
Shewanella putrefaciens
Authors: Khashe Shideh , Janda J. Michael
Published: December 2019

We characterized 49 strains of
Shewanella
spp. from clinical (
n
= 31) and nonhuman (
n
= 18) sources. Most
Shewanella alga
organisms (Gilardi biovar 2; Centers for Disease Control and Prevention [CDC] biotype 2) originated from clinical material (92%), failed to produce acid from carbohydrates other than
d
-ribose, and were biochemically and enzymatically fairly homogeneous. In contrast,
Shewanella putrefaciens
organisms (Gilardi biovars 1 and 3; CDC biotype 1) were more often associated with nonhuman sources (70%), were able to utilize a number of sugars (sucrose,
l
-arabinose, and maltose), and were found to exhibit wider variations in biochemical characteristics; three biotypes within
S. putrefaciens
were detected. Notable differences between the two species in enzymatic activity, determined with the API-ZYM system (bioMérieux, Hazelwood, Mo.), and cellular fatty acid profiles, determined by the MIDI system (Microbial ID Inc., Newark, Del.), were also detected. Pathogenicity studies of mice indicate that
S. alga
appears to be the more virulent species, possibly due to the production of a hemolytic substance.
Evaluation of the Dade MicroScan MICroSTREP Antimicrobial Susceptibility Testing Panel with Selected
Streptococcus pneumoniae
Challenge Strains and Recent Clinical Isolates
Authors: Jorgensen J. H. , McElmeel M. L. , Crawford S. A.
Published: December 2019

The MicroScan MICroSTREP panel is a recently marketed frozen broth microdilution panel for susceptibility testing of various streptococci, including
Streptococcus pneumoniae
. The panel contains 10 antimicrobial agents in cation-adjusted Mueller-Hinton broth supplemented with 3% lysed horse blood, similar in concept to the National Committee for Clinical Laboratory Standards (NCCLS) reference broth microdilution method for testing streptococci. A group of 210 isolates of
S. pneumoniae
were selected to include isolates with previously documented resistance to agents incorporated in the MICroSTREP panel, as well as recent invasive clinical isolates. All isolates were tested simultaneously with the MICroSTREP panel and an NCCLS reference panel whose drug concentrations were prepared to coincide with those of the MICroSTREP panel. Of the 210 isolates, 5 failed to grow in the MICroSTREP panel; 3 of those also did not grow in the reference panel. Essential agreement of MICs determined by the two methods (test MIC ± one dilution of the reference MIC) was 99.6% overall and ranged from 98.0% with chloramphenicol to 100% with penicillin, ceftriaxone, erythromycin, tetracycline, and vancomycin. There were no very major or major interpretive category errors resulting from the MICroSTREP panel tests. Minor interpretive category errors ranged from 12.2% with cefotaxime and 9.8% with ceftriaxone (due mainly to clustering of MICs for the selected strains near the breakpoints) to 0% with chloramphenicol and vancomycin. These results indicate that the MicroScan MICroSTREP frozen panels provide susceptibility results with pneumococci that are essentially equivalent to results derived by the NCCLS reference broth microdilution procedure.
A Nosocomial Cluster of
Candida inconspicua
Infections in Patients with Hematological Malignancies
Authors: D’Antonio Domenico , Violante Beatrice , Mazzoni Aldo , Bonfini Tiziana , Capuani M. Assunta , D’Aloia Francesco , Iacone Antonio , Schioppa Francesco , Romano Ferdinando
Published: December 2019

Candida inconspicua
was recovered from three patients with hematological malignancies. Two patients had intravenous-catheter-associated fungemia, whereas the third had fungal hepatitis. The three cases of infection occurred over a period of 1 month in patients staying in adjacent single rooms. In vitro susceptibility testing of fungal strains showed all isolates to be resistant to fluconazole, with MICs greater than 32 μg/ml. All of the strains had identical DNA restriction profiles and randomly amplified polymorphic DNA fingerprints. These data suggest a nosocomially acquired infection emanating from a common source within the hospital environment.
Detection of Respiratory Syncytial Virus A and B and Parainfluenzavirus 3 Sequences in Respiratory Tracts of Infants by a Single PCR with Primers Targeted to the L-Polymerase Gene and Differential Hybridization
Authors: Eugene-Ruellan Geneviève , Freymuth François , Bahloul Chokri , Badrane Hassan , Vabret Astrid , Tordo Nöel
Published: December 2019

A reverse transcription-PCR and hybridization-enzyme immunoassay (RT-PCR-EIA) has been developed to identify the major agents of bronchiolitis in infants: respiratory syncytial viruses A and B (RSVA and RSVB) and parainfluenzavirus 3 (PIV3). Two primer sets (P1-P2 and P1-P3) were selected in a conserved region of the polymerase L gene. In infected cell cultures, this method detected RSVA (
n
= 14), RSVB (
n
= 13), and PIV3 (
n
= 13), with the exclusion of PIV1 (
n
= 4), PIV2 (
n
= 3), measles virus (
n
= 6), mumps virus (
n
= 4), influenza A virus (
n
= 11), and influenza B virus (
n
= 4). The differentiation of the amplicons by restriction fragment length polymorphism (RFLP) showed a
Pvu
II site for PIV3 strains and an
Ava
II site for RSV strains, with RSVA distinguished from RSVB by
Bgl
II. The hybridization-EIA, using three internal probes specific for each virus, correlated with the immunofluorescence assay (IFA) and RFLP results. Clinical aspirates from 261 infants hospitalized with bronchiolitis were tested by IFA, viral isolation technique (VIT), and RT-PCR-EIA. RT-PCR-EIA detected RSV sequences in 103 samples (39.4%), and IFA-VIT detected RSV sequences in 109 cases (41.7%). A few samples (2.6%) were IFA-VIT positive but PCR negative, and one sample was RT-PCR-EIA positive only. RT-PCR-EIA detected PIV3 sequences in 14 of the 15 IFA-VIT-positive isolates. The two methods showed very good correlation (96.9%), but RT-PCR-EIA was clearly more efficient in typing, leaving 5% non-A, non-B isolates, while IFA failed to resolve 23% of the isolates. The two methods contradicted each other for <5% of the isolates.
Highly Sensitive Method for Amplification of Human Immunodeficiency Virus Type 2 DNA
Authors: Damond Florence , Loussert-Ajaka Ibtissam , Apetrei Cristian , Descamps Diane , Souquière Sandrine , Leprêtre Annie , Matheron Sophie , Brun-Vézinet Françoise , Simon François
Published: December 2019

We evaluated a new human immunodeficiency virus type 2 (HIV-2) DNA amplification strategy based on peripheral blood mononuclear cell long PCR (XL PCR) followed by nested PCR amplification. The primers used were located in the highly conserved long terminal repeat and in the
pol
regions of the genome. Five primer pairs corresponding to different regions of the HIV-2
env
gene were used in the nested step. Samples from 42 patients were tested, which yielded positive amplification with at least two primer pairs in 40 (95%) samples. A primer pair (EB2/EB5) located on the V3 region succeeded in amplifying proviral DNA in 40 samples.
Sensitivity of Fluorochrome Microscopy for Detection of
Mycobacterium tuberculosis
versus Nontuberculous Mycobacteria
Authors: Wright Paul W. , Wallace Richard J. , Wright Nathan W. , Brown Barbara A. , Griffith David E.
Published: December 2019

The results for 6,532 consecutive mycobacterial respiratory specimens collected from 1,040 patients from 1993 to 1995 in a Texas hospital were studied to determine the sensitivity of fluorescence microscopy for detection of
Mycobacterium tuberculosis
and nontuberculous mycobacteria (NTM). Smears were positive for acid-fast bacilli (AFB) in 63% (677 of 1,082) of specimens growing
M. tuberculosis
and 56% (638 of 1,148) of specimens growing the four most common species of NTM. Smear positivity by species was 58% (446 of 776) for
M. avium
complex, 51% (154 of 300) for rapidly growing mycobacteria (98% were
M. abscessus
), 78% (29 of 37) for
M. kansasii
, and 26% (9 of 35) for
M. gordonae
. Definite or probable disease by clinical criteria was present in 79% of patients with
M. avium
complex, 93% of patients with rapidly growing mycobacteria, 100% of patients with
M. kansasii
, and 0% of patients with
M. gordonae
. Patients with
M. avium
complex had a low incidence of AIDS (7%), and approximately 50% of non-AIDS patients had upper-lobe cavitary disease and 50% had nodular bronchiectasis. Only 23 of 6,532 (0.35%) of AFB smears were positive with a negative culture excluding patients on therapy for established mycobacterial disease. These studies suggest that NTM are as likely as
M. tuberculosis
to be detected by fluorescent microscopy in specimens from patients from areas endemic for NTM lung disease and at low risk for AIDS.
Detection of Norwalk Virus and Other Genogroup 1 Human Caliciviruses by a Monoclonal Antibody, RecombinantAntigen-Based Immunoglobulin M Capture Enzyme Immunoassay
Authors: Brinker James P. , Blacklow Neil R. , Estes Mary K. , Moe Christine L. , Schwab Kellogg J. , Herrmann John E.
Published: December 2019

Sera obtained from two groups of adult volunteers infected with Norwalk virus (NV) and two groups of patients involved in two natural outbreaks were tested for NV-reactive immunoglobulin M (IgM) by use of a monoclonal antibody, recombinant-antigen-based IgM capture enzyme immunoassay (EIA). No NV-reactive IgM was detected in the preinoculation sera of 15 volunteers, and 14 of 15 showed NV-reactive antibodies postinfection with NV. All of the volunteers showed IgG seroconversion to NV. In the outbreak studies, all 9 persons in one outbreak and 19 of 24 in another outbreak had NV-reactive IgM. In the first outbreak, only three of nine seroconverted to NV, which was likely due to late collection of acute-phase sera. In the second outbreak, 21 of 24 showed IgG seroconversion to NV. Sequencing of viruses isolated from five stool samples selected from those in the second outbreak showed that they were human calicivirus (HuCV) genogroup 1 viruses related, but not identical, to NV. In the volunteer studies, NV-reactive IgM was first detected 8 days postinoculation. The time of development of NV-reactive IgM antibodies in natural outbreaks was estimated to be similar to that found in the volunteer studies. Sera from three Hawaii virus-infected volunteers, four Snow Mountain virus patients, and 80 healthy individuals were negative for NV-reactive IgM, indicating test specificity for HuCV genogroup I infections. This capture IgM EIA is suitable for diagnosis of NV and other HuCV genogroup I infections and is especially useful when sera and fecal samples have not been collected early in the course of an outbreak.
Misidentification of Unusual
Aeromonas
Species as Members of the Genus
Vibrio
: a Continuing Problem
Authors: Abbott Sharon L. , Seli Lourdes S. , Catino Michael , Hartley Michael A. , Janda J. Michael
Published: December 2019

Two unusual cases of
Aeromonas
infection are described, one associated with bacteremia (
Aeromonas schubertii
) and another in which the organism was recovered from an infected gall bladder (
Aeromonas veronii
biotype veronii). These strains were initially identified as
Vibrio damsela
and
Vibrio cholerae
by the Vitek and API 20E systems, respectively. Use of appropriate screening tests and familiarity with the newer
Aeromonas
species could prevent initial misidentifications and potential public health consequences.
Long-Term Survival of
Streptococcus pneumoniae
at Room Temperature on Dorset Egg Medium
Authors: Wasas Avril D. , Huebner Robin E. , De Blanche Mignon , Klugman Keith P.
Published: December 2019

Forty-five isolates of
Streptococcus pneumoniae
were inoculated on Dorset egg and supplemented Columbia agar base media, incubated overnight at 37°C, and then kept at room temperature (RT; 21°C) or 4°C. Long-term viability was best at RT for both media, with all isolates remaining viable on Dorset egg medium for 44 days; viability was 90 and 57% on Columbia agar base medium after 7 and 30 days. We recommend the use of Dorset egg medium for the maintenance of pneumococci at RT.
Diagnosis of
Mycoplasma pneumoniae
Infection in Autopsy and Open-Lung Biopsy Tissues by Nested PCR
Authors: Talkington Deborah F. , Thacker W. Lanier , Keller David W. , Jensen Jørgen S.
Published: December 2019

A nested PCR specific for the
Mycoplasma pneumoniae
P1 gene was used to diagnose mycoplasma infection in two cohort patients with severe pneumonia within 24 h of tissue receipt. A postmortem diagnosis of
M. pneumoniae
infection was obtained for the first patient, who died without the collection of appropriate paired samples for serodiagnosis. An open-lung biopsy obtained from the second patient allowed a quick, definitive diagnosis and proper selection of therapy.