bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation of dematiaceous pathogenic fungi from a feed and seed warehouse
Authors: Espinel-Ingroff A , Kerkering T M , Shadomy H J
Published: January 2020

In an epidemiological study, nine isolates of dematiaceous fungi were recovered from the interior of a local feed and seed warehouse. Sample sites include brick walls and floors. Air samples also were included. Samples were collected in saline and plated on Mycobiotic and Sabouraud agar. The nine dematiaceous fungi recovered from these samples were identified with microscopic morphology, thermotolerance, biochemical reactions, and animal virulence test. Four isolates were identified as nonpathogens on the basis of positive gelatin tests. The identified pathogens included Fonsecaea pedrosoi, Cladosporium bantianum (C trichoides), Wangiella dermatitidis (Dixon et al., Mycopathologia 70:153-161, 1980), and Exophiala jeanselmei. These five organisms were injected into NCI/ALB mice. Only the isolate of C. bantianum was neurotropic, as demonstrated histopathologically and by the recovery of the organism from brain tissue. None of the remaining four isolates were seen or cultured from any of the mouse tissues analyzed. The recovery of pathogenic dematiaceous fungi from environmental sites is not uncommon. However, this study is noteworthy in that it represents only the second reported isolation of C. bantianum and the first isolation of F. pedrosoi from the environment in North America and suggests that these fungi may be more ubiquitous in this region that previously believed.
Carriage of Streptococcus agalactiae in women and neonates and distribution of serological types: a study in Brazil
Authors: Benchetrit L C , Fracalanzza S E , Peregrino H , Camelo A A , Sanches L A
Published: January 2020

The prevalence of group B streptococcal carriage was evaluated in nonpregnant women and in mothers and their offsprings. The overall carriage rate of group B streptococci at one site was 18.2%. Streptococci were recovered from one or more of the sites sampled in 25.6% of mothers and 15.4% of newborn infants. The maternal genital carriage rate was 18.6%, and acquisition of the organism from the mother was assessed by serological typing of group B streptococcal isolates in the mother-infant pairs. A cervical carriage rate of 16.3% was seen in nonpregnant women.
Cellular fatty acid composition of Haemophilus equigenitalis
Authors: Sugimoto C , Miyagawa E , Mitani K , Nakazawa M , Isayama Y
Published: January 2020

The cellular fatty acid composition of eight Haemophilus equigenitalis strains was determined by gas-liquid chromatography. All strains showed a grossly similar pattern characterized by large amounts of 18:1 and 16:0. The amounts of 16:1, 18:2, 18:0, 3-OH 14:0, 3-OH 16:0, and 3-OH 18:1 were relatively small.
Microtube coagulase test for detection of coagulase-positive staphylococci
Authors: Goldstein J , Roberts J W
Published: January 2020

Studies were performed to determine the sensitivity and specificity of a new microtube method for the detection of coagulase production by Staphylococcus aureus. Rabbit plasma containing EDTA was added to and lyophilized in API microtubes. Two standard coagulase plasmas containing EDTA were used in the conventional macrotube test and served as a basis for comparison. No false-positive or false-negative reactions were encountered with the microtube system. With this system, 53% of the coagulase-positive strains tested were detected within 1 h after inoculation, 82% were detected after 2 h, 97% were detected after 3 h, and 99% were detected after 4 h. With the first conventional method, 45, 81, 96, and 98% of the positive strains were detected in 1, 2, 3, and 4 h, respectively, whereas with the second conventional method, only 6% of the positive strains were detected in 1 h, 24% in 2 h, 66% in 3 h, and 81% in 4 h. With the microtube method, 5 of the 139 coagulase-producing strains studied reverted to negative between 5 and 24 h after inoculation, whereas 9 reverted with the more rapid conventional method, and no reversions occurred with the second conventional method. All reversions involved strains which caused gelation of plasma within 1 h after inoculation. The data obtained showed that 99% of the coagulase-positive strains tested could be detected within 4 h by the microtube method. In addition, the microtube method offers a more convenient and economical format for the performance of the coagulase tube test.
Culture medium for confirmation of penicillin-resistant and penicillinase-producing Neisseria gonorrhoeae
Authors: Perine P L , Westbrook W G , Biddle J W , Lewis J S , Martin J E
Published: January 2020

A culture method for the isolation and identification of penicillinase (beta-lactamase)-producing Neisseria gonorrhoeae (PPNG) was evaluated in the Philippines where PPNG are common. The method uses plastic biplates containing standard Martin-Lewis gonorrhea culture medium in one side of the biplate and PPNG-selective medium containing 1.5 microgram of penicillin G per ml and a suspension of Sarcina lutea (Micrococcus lutea) that was susceptible to 0.01 microgram of penicillin G per ml in the other side. Penicillin-resistant gonococci grow on both sides of the biplate. The hydrolysis of penicillin by beta-lactamase permits the growth of S. lutea around PPNG colonies. With this medium we successfully identified 11 of 12 PPNG strains growing on primary isolation plates. A 48- to 72-h incubation period was needed, however, for visible growth of S. lutea around PPNG colonies. A unique advantage of this method was the identification of non-PPNG strains which also grew on penicillin-containing medium but did not allow growth of S. lutea. These relatively penicillin-resistant strains were the cause of infections which were not cured by penicillin treatment in 2 of 11 patients.
Pseudomonas aeruginosa: changes in antibiotic susceptibility, enzymatic activity, and antigenicity among colonial morphotypes
Authors: Sheehan D J , Janda J M , Bottone E J
Published: January 2020

Colonial variants of Pseudomonas aeruginosa have received renewed interest because of their occurrence in sputum cultures of patients with cystic fibrosis. We encountered 11 strains of P. aeruginosa from various body sites of non-cystic fibrosis patients. The strains showed two to three colonial variants, including smooth, rough, and iridescent morphotypes that arose from subculture of a single colony of P. aeruginosa originating from a primary source. The colonial segregants differed in antibiotic susceptibility (resistance to gentamicin, carbenicillin, chloramphenicol, and tetracycline), presence or absence of exoenzymes (gelatinase and elastase), degree of proteolytic activity (caseinase), pigmentation, and antigenicity. These observations suggest that in vivo dissociation with concomitant changes in enzymatic and surface properties might greatly enhance invasiveness. Concurrent differences in antimicrobial susceptibility among the colonial variants could account in some instances for the failure of antibiotic treatment in P. aeruginosa infections in which one would anticipate a positive therapeutic response.
Peptone-yeast autolysate-fetal bovine serum 10, a simple, inexpensive liquid medium for cultivation of Leishmania spp
Authors: Palomino J C
Published: January 2020

A simple liquid medium for the cultivation of Leishmania parasites is described. Leishmania brasiliensis and Leishmania peruviana cultured in this medium reached cell densities greater than 10(7) promastigotes per ml within 7 days. This medium compares very favorably with the more complex media used to cultivate Leishmania spp. and other hemoflagellates.
Characterization of antibody responses in legionellosis with an immunofluorometric assay
Authors: Black C M , Pine L , Reimer C B , Benson R F , Wells T W
Published: January 2020

A solid-phase immunofluorometric assay was used to qualitatively characterize and precisely measure human immunoglobulin class-specific antibody responses in legionellosis. Stable antigen preparations consisted of cells grown at 25 degrees C that were killed, fixed with Formalin vapors, washed, and lyophilized. Working-curve material consisted of dilutions of selected convalescent sera. Linear regressions of logit transformations of relative fluorescence intensities versus the logarithm of the relative concentrations of sera were determined to give immunoglobulin class-specific antibody levels from uninfected and infected individuals. Each fluorescence intensity obtained with immunoglobulin class-specific antibody was converted to a multiple of the median fluorescence intensity obtained with sera from uninfected individuals. A presumptive-positive acute-phase legionellosis serum was defined for each immunoglobulin class by a multiple of the normal median fluorescence intensity that was greater than the multiple of the normal median from approximately 97% of the uninfected population.
Accuracy and precision of the autobac system for rapid identification of Gram-negative bacilli: a collaborative evaluation
Authors: Barry A L , Gavan T L , Smith P B , Matsen J M , Morello J A , Sielaff B H
Published: January 2020

Gram-negative bacilli were identified within 3 to 6 h by determining susceptibility to 18 different antibacterial agents in the Autobac I system and by applying a two-stage quadratic discriminant analysis to the susceptibility patterns. The Autobac system was compared with standard reference methods for identifying glucose nonfermenters and glucose fermenters. Intralaboratory and interlaboratory precision of the Autobac system was comparable to that of the reference methods. Sensitivity (accuracy) and specificity of the two systems were also comparable, although there were some differences with certain species. Autobac responses were considered to be equivocal (needing additional tests) if the relative probability of an accurate identification was less than 0.70. Only 5% of 2,889 strains produced such equivocal results; a similar number of strains gave low probability levels with the reference methods. When the two systems disagreed, an independent reference laboratory arbitrated, confirming 49% of the Autobac responses and 36% of the reference identifications. With equivocal responses excluded, the overall accuracy of the Autobac system was 95.3% compared with 95.9% for the reference method. The respective accuracy estimates would be 93.8% and 93.1% if all first-choice identifications were evaluated.
Clinical studies of a new latex particle agglutination test for detection of Haemophilus influenzae type b polyribose phosphate antigen in serum, cerebrospinal fluid, and urine
Authors: Shaw E D , Darker R J , Feldman W E , Gray B M , Pifer L L , Scott G B
Published: January 2020

A new latex particle agglutination test for direct detection of Haemophilus influenzae type b polyribose phosphate antigen in serum, cerebrospinal fluid, or urine was evaluated from studies at four clinical centers. Although use of a serum buffer significantly reduced inconclusive agglutination of the latex particles, the retesting of serum samples, after heat inactivation and dilution, resolved all serum samples, with one exception, as reactive or nonreactive for the presence of the polyribose phosphate antigen. A clinical accuracy of 100% was obtained for the latex particle agglutination method in respect to its capability for detection of polyribose phosphate antigen in all patients with confirmed infection by H. influenzae type b.
Anti-Poly(glycerolphosphate) in Human Sera
Authors: Doyle Ronald J. , Sonnenfeld Elaine M. , Cost Karen , Thaniyavarn Suthep
Published: January 2020

Ultrasonic extracts from staphylococci contained red cell-sensitizing poly(glycerolphosphate)teichoic acid antigen. The antigen may contribute to the variability of precipitin reactions used in the diagnosis of
Staphylococcus aureus
infection.
Evaluation of a qualitative isocitrate lyase assay for rapid presumptive identification of Yersinia pestis cultures
Authors: Quan T J , Vanderlinden J J , Tsuchiya K R
Published: January 2020

Qualitative rapid tests for isocitrate lyase activity were positive for all of 1,695 Yersinia pestis cultures tested but for none of 382 cultures of other gram-negative species. The test is simple, required only commonly available, easily prepared reagents, and provided clear-cut positive or negative results within 20 min.
Presumptive identification of streptococci with a new test system
Authors: Facklam R R , Thacker L G , Fox B , Eriquez L
Published: January 2020

A test is described that could replace bacitracin susceptibility for presumptive identification of group A streptococci as well as 6.5% NaCl agar tolerance for presumptive identification of enterococcal streptococci. The L-pyrrolidonyl-beta-naphthylamide test, based on hydrolysis of pyrrolidonyl-beta-naphthylamide, was used in conjunction with the CAMP and bile-esculin tests to presumptively identify the streptococci. Among the beta-hemolytic streptococci; 98% of 50 group A, 98% of 46 group B, and 100% of 70 strains that were not group A, B, or D were correctly identified by the new presumptive test scheme. Among the non-beta-hemolytic streptococci; 96% of 74 group D enterococcal, 100% of 30 group D nonenterococcal, and 82% of 112 viridans strains were correctly identified by the new presumptive test scheme.
Detection of influenza virus neuraminidase-specific antibodies by an enzyme-linked immunosorbent assay
Authors: Khan M W , Gallagher M , Bucher D , Cerini C P , Kilbourne E D
Published: January 2020

An enzyme-linked immunosorbent assay was developed for the titration of antibodies in human sera to influenza virus neuraminidase, employing partially purified N1 neuraminidase. Specificity of the test was demonstrated, and the test was more sensitive than either the conventional neuraminidase inhibition or plaque size reduction tests in detecting anti-neuraminidase antibody.
Evaluation of the MICUR system for quantitative antimicrobial susceptibility testing: a multiphasic comparison with reference methods
Authors: Jones R N , Barry A L , Bigelow J , Gavan T L , Thornsberry C
Published: January 2020

Four laboratories participated in a three-phase study to evaluate the MICUR antimicrobial broth microdilution system (Boehringer Mannheim Diagnostics, Inc., Houston, Tex.). The dried-antimicrobial agent MICUR system was compared with a reference broth microdilution method (National Committee for Clinical Laboratory Standards) by using 304 recently isolated clinical strains and two collections of stock or challenge organisms. Of 7,092 minimum inhibitory concentration (MIC) datum pairs derived from the clinical isolates, 96.6% were within an acceptable (+/- 1 log2 dilution) range. MICUR MICs agreed with the reference broth microdilution method MICs in 95.3% of 6,840 MIC pair determinations performed on stock or challenge cultures. The MICUR intralaboratory reproducibility within +/- 1 log2 dilution step for the clinical isolates was 98.4%. The MICUR intralaboratory and interlaboratory reproducibilities for 26 stock cultures were 98.4 and 95.1%, respectively. For 180 challenge cultures (4,199 MIC pairs) which were included in the MICUR testing to provide a wide variety of antimicrobial susceptibility and resistance patterns, the results for 92.5% were in close agreement with the reference broth microdilution results. No specific resistance mechanism went unrecognized by this new commercial system. The MICUR system gives comparable MIC results when evaluated against the reference broth microdilution method, and it would be acceptable for use in clinical microbiology laboratories.
Evaluation of two photometers used in enzyme-linked immunosorbent assays
Authors: Genta V M , Bowdre J H
Published: January 2020

The performance of two commercially available high-speed photometers, designed for through-the-plate reading, was evaluated. Linearity of instrumental reading and reproducibility of same-day and 2-day measurements were assessed by least-squares analysis and analysis of variance, respectively. For both instruments, the photometric error was on the order of thousandths of an absorbance unit and was much smaller than the error of the currently available enzyme-linked immunosorbent assays.
Determination of the range of antibacterial activity by use of viable counts
Authors: Lorian V , Atkinson B A
Published: January 2020

The activity of three aminoglycosides and six beta-lactam antibiotics on strains of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, and enterococci was studied. The minimal inhibitory concentrations (MICs), the minimal bactericidal concentrations (MBCs), and the minimal antibiotic concentrations (MACs) were determined after 5 h of incubation in broth cultures by colony-forming-unit counts. The MICs were also determined by agar dilution after 24 h of incubation. The MICs on agar after 24 h of incubation were higher than those in broth after 5 h of incubation. The differences ranged from 1.1- to 14.2-fold, but in most cases were only three- to fivefold (P less than 0.05 to less than 0.001). The MBCs at 5 and 24 h were comparable in 71% of tests. For current practice, the MBC of enterococci can be determined after 5 h of incubation with antibiotics. The aminoglycosides showed MBCs which were closer to the MICs than were those of the beta-lactam antibiotics, which required a higher multiple of the MIC to show a bactericidal effect. The MBCs of oxacillin and cefamandole for S. aureus after 5 h of incubation were greater than 128 times the respective MICs. The MACs ranged from 1/1.5 to 1/7 of the 5-h MICs. The three endpoints, MIC, MBC, and MAC, indicate the antibacterial range of an antibiotic in terms of inhibition of growth and bacterial survival. The data suggest that the antibacterial range of an antibiotic is similar for most strains of a given species and is, to some extent, a characteristic of similar antibiotics.
Sodium dodecyl sulfate-polyacrylamide gel typing system for characterization of Neisseria meningitidis isolates
Authors: Mocca L F , Frasch C E
Published: January 2020

Thirty to fifty percent of group B and group C Neisseria meningitidis carrier isolates are not serotypable with existing outer membrane protein typing sera. A typing system based on differences in the outer membrane protein profiles after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was therefore developed as an adjunct to existing serotyping methods. Although most N. meningitidis strains contain several outer membrane proteins visible by SDS-PAGE, there are only one to three predominant proteins. The SDS-PAGE profiles of these major proteins were used to establish 10 different PAGE types. Greater than 95% of all meningococcal isolates, regardless of serogroup, fit into 1 of the 10 PAGE types. The outer membrane protein profile of individual strains after SDS-PAGE was constant when outer membrane fractions were prepared from the same strain on several different days. A comparison of gel profiles of meningococcal isolates obtained from different sites of the same patient revealed no significant differences among both major and minor proteins for isolate sets thus far examined. Characterization of strains by PAGE type can be a valuable epidemiological tool in addition to serotyping and in the absence of specific serotype antisera.
Inactivation of rabies virus in reagents used for the fluorescent rabies antibody test
Authors: White L A , Chappell W A
Published: January 2020

Procedures for inactivating rabies virus in reagents used for the fluorescent rabies antibody test are described. Mouse brain adsorbing suspensions containing greater than or equal to 10(9) 50% lethal doses of virus per ml were rendered noninfectious by treatment with 0.1% beta-propiolactone or by heating at 56 degrees for greater than or equal to 30 min. Viable virus in tissue impression smears was inactivated by acetone fixation at 50 degrees C for greater than or equal to 30 min or by immersion in 0.1% beta-propiolactone at 37 degrees C for 2 h. Inactivated reagents gave specific and sensitive reactions in the fluorescent rabies antibody test.
Evaluation of a new rapid plasma reagin card test as a screening test for syphilis
Authors: Perryman M W , Larsen S A , Hambie E A , Pettit D E , Mullally R L , Whittington W
Published: January 2020

This study evaluates the American Dade (Biokit Laboratories) rapid plasma reagin (Dade RPR) card test, currently used in Spain for the diagnosis of syphilis, which has been recently released to the U.S. market. Used as a basis for comparison with the Dade card test were the 18-mm standard rapid plasma reagin (standard RPR) card test and the Venereal Disease Research Laboratory (VDRL) slide test, using both fresh sera obtained from 505 individuals and paired serum-plasma specimens from 174 individuals. Results obtained proved the Dade RPR card test with serum to be very similar to the standard RPR card test; sensitivity was 92.3% and specificity was approximately 99% for both RPR card tests. Although the sensitivity of the VDRL slide test was lower at 88.5%, its specificity was also approximately 99%. Quantitatively, the agreement +/- 1 dilution between the two card tests was 93.6%. Agreement +/- 1 dilution between the Dade RPR card test and the VDRL slide test was 46.5% for sera, comparable to the standard RPR-VDRL agreement of 50%. In the limited evaluation of the RPR card tests with plasma, the specificity was 99.4% and the sensitivity was 100% for both tests. Quantitative agreement +/- 1 dilution between plasma and serum pairs was 100% for the Dade RPR card test. Our results showed that the Dade RPR card test is as sensitive and as specific as the standard RPR card test. Therefore, it was concluded that one card test has no particular advantage over the other.
Comparison of CampyPak II with standard 5% oxygen and candle jars for growth of Campylobacter jejuni from human feces
Authors: Wang W L , Luechtefeld N W , Blaser M J , Reller L B
Published: January 2020

To determine optimal temperature and atmospheric conditions for isolating Campylobacter jejuni from fecal specimens of humans, we studied six laboratory isolates and 19 fecal specimens that were known to contain C. jejuni. We compared incubations in 5% oxygen, the CampyPak II (BBL Microbiology Systems, Cockeysville, Md.) with 6 plates per jar (CP-6) and 12 plates per jar (CP-12), and candle jars at 37 and 42 degrees C. At both temperatures, the colony sizes for the laboratory strains were larger in the 5% O2 and the CP-6 than under the other two conditions. For the primary isolations, CP-12 failed to detect one and two campylobacters at 42 and 37 degrees C, respectively, whereas the candle jar failed to detect one at 42 degrees C and four at 37 degrees C. Colony size was again larger in the 5% O2 and the CP-6. For all four atmospheric conditions tested, colonies were significantly larger at 42 degrees C than at 37 degrees C. These studies showed that incubation at 42 degrees C in either 5% O2 or the CampyPak II with six plates per jar was optimal for primary isolation of C. jejuni from fecal specimens of humans. The candle jars incubated at 42 degrees C appeared to be satisfactory for primary isolation of C. jejuni from human feces, but incubation at 37 degrees C was not acceptable.
Serological comparison of two collections of Vibrio cholerae non O1
Authors: Brenner D J , Davis B R , Kudoh Y , Ohashi M , Sakazaki R , Shimada T , Smith H L
Published: January 2020

Two large, independently obtained collections of vibrio cholerae non O1, containing 59 and 67 reference strains, respectively, were compared serologically in four laboratories. Twenty strains in each collection were considered identical, and an additional 16 strains in each collection were probably identical. Twenty-eight unique strains were identified, and inconclusive results were obtained with 25 strains. Nine strains were not considered V. cholerae in at least one testing laboratory. Of these, five showed insufficient correspondence to V. cholerae O1 by DNA hybridization to be considered V. cholerae.
Comparison of an enzyme-linked immunoassay and a quantitative indirect fluorescent-antibody test with the conventional indirect fluorescent-antibody test for detecting antibodies to Toxoplasma gondii
Authors: Violand S A , Mitchell T G , Kleeman K T
Published: January 2020

Two new methods for the detection of antibodies to Toxoplasma gondii, an enzyme-linked immunosorbent assay and a quantitative immunofluorescence assay, were evaluated and compared with the conventional indirect fluorescent-antibody slide test. Each of 100 human sera was assayed twice by the three procedures. Both the enzyme-linked immunosorbent assay and the quantitative immunofluorescence assay correlated well with serologically positive (indirect fluorescent-antibody titer greater than or equal to 1:32) and negative sera. The enzyme-linked immunosorbent assay was more specific, but less sensitive, than the quantitative immunofluorescence assay. However, the quantitative immunofluorescence assay was more reproducible and more rapid than the enzyme-linked immunosorbent assay.
Evaluation of an enzyme-linked immunosorbent assay specific for human immunoglobulin G as a Screening test for detecting anti-toxoplasma antibodies
Authors: Woodward B C
Published: January 2020

An evaluation of the enzyme-linked immunosorbent assay (ELISA) as a screening test for immunoglobulin G class-specific anti-Toxoplasma antibodies was conducted. Results for 191 serum specimens assayed by the ELISA, indirect hemagglutination (IHA), and methylene blue dye tests indicated that good qualitative agreement exists among these tests. High ELISA titers relative to methylene blue dye titers may be attributed in part to the presence of rheumatoid factor. ELISA results were found to be reproducible. A parallel study of 1,760 sera assayed by ELISA and IHA was performed with 3.0-mm-diameter serum filter paper spots as a source of specimen. When a 1:64 titer and 40 IU were used as threshold values for IHA and the ELISA, respectively, 4.8% of the specimens tested were positive in both tests. An additional 2% of these specimens were ELISA positive and IHA negative, whereas 2% were ELISA negative and IHA positive. The total number of positive specimens by either test (7%) closely agreed with previously reported results. In view of these data, the simplicity of the test, and relative economic considerations, the ELISA may be considered an alternative method for screening for anti-Toxoplasma antibodies.
Evaluation of the anticomplement immunofluorescence test for detection of antibody to varicella-zoster virus
Authors: Preissner C M , Steinberg S P , Gershon A A , Smith T F
Published: January 2020

The anticomplement immunofluorescence (ACIF) test was compared with complement fixation and fluorescent antibody to membrane antigen procedures for the detection of antibody to varicella-zoster virus. All of 50 sera from pregnant women contained antibody measured by ACIF (titer, greater than or equal to 1:10); only 27 (54%) were positive by complement fixation (P less than 0.01). For 16 paired sera obtained before and after varicella-zoster virus infection and tested by ACIF and fluorescent antibody to membrane antigen, the result agreed in 27 determinations (sensitivity, 94%; specificity, 81%). Of 99 sera submitted for routine determinations of immune status to the virus, 89 showed comparable results for both tests (sensitivity, 92.5%; specificity, 88%). The ACIF test offers a specific and sensitive alternative to the fluorescent antibody to membrane antigen procedure for the detection of antibody to varicella-zoster virus. In addition, the ACIF test is rapid, easy to perform, and uses commercially available reagents.
Isolation of Chlamydia trachomatis in Untreated MMC-E mouse epithelial cells
Authors: Keski-Oja J , Paavonen J
Published: January 2020

The susceptibility of the epithelial mouse embryo cell line MMC-E to infection with Chlamydia trachomatis was studied by using chlamydiae from both laboratory strain L2 and clinical specimens. MMC-E cells were sensitive to infection with C. trachomatis without any pre- or posttreatments, and their susceptibility for isolation was comparable to that of the conventionally used irradiated McCoy cells.
Serotype B/C Cryptococcus neoformans isolated from patients in nonendemic areas
Authors: Fromtling R A , Shadomy S , Shadomy H J , Dismukes W E
Published: January 2020

Of 90 clinical isolates of Cryptococcus neoformans studied, 3 were determined to be serotype B/C. The patients from whom these B/C isolates were obtained were identified as never having lived in or visited the areas associated with B/C serotypes. This finding suggests a broader geographic distribution of this serotype group than previously believed. The glycine-cycloheximide-phenol red medium described by Salkin and Hurd (J. Clin. Microbiol. 15:169-171, 1982) was shown to be more accurate in differentiating A/D and B/D serotype pairs of C. neoformans than the creatinine-dextrose-bromthymol blue medium described by Kwon-Chung et al. (Int. J. Syst. Bacteriol. 28:616-620, 1978).
Prospective survey of fecal, urinary tract, and environmental colonization by Providencia stuartii in two geriatric wards
Authors: Hawkey P M , Penner J L , Potten M R , Stephens M , Barton L J , Speller D C
Published: January 2020

A prospective survey of fecal, urinary tract, and environmental colonization by Providencia stuartii in two wards was undertaken over a 5-month period. Eight of 53 male patients and 2 of 89 female patients were colonized with the endemic serotype O:63. Two patterns of colonization were found on the male ward. Two patients had persistent urinary tract colonization with no detectable fecal carriage. The other patients had fecal carriage, in some cases persistent, with intermittent urinary tract colonization. The ward environment was in general not contaminated. This study demonstrates that fecal colonization of patients by P. stuartii may be an important and previously underestimated nosocomial reservoir.
Staphylococcus saprophyticus as a cause of urinary tract infections
Authors: Marrie T J , Kwan C , Noble M A , West A , Duffield L
Published: January 2020

Our objectives in this study were to elucidate various aspects of the epidemiology of Staphylococcus saprophyticus. This organism was isolated from the midstream urine specimens of 7.5% of 145 college women with frequency and urgency of urination and dysuria, but from only 0.07% of 14,835 urine specimens from adult inpatients at the Victoria General Hospital. It was found to be part of the urethral flora of only 2% of healthy women. Other staphylococci which formed part of the urethral flora of 100 healthy women included S. epidermidis (59 women), S. hominis (15 women), S. haemolyticus (13 women), S. warneri (9 women), and S. aureus (6 women). Finally, we determined that resistance to the 5-micrograms novobiocin disk has a 93% positive predictive accuracy as a presumptive test for S. saprophyticus.
Rapid evaluation of female patients exposed to gonorrhea by use of the Limulus lysate test
Authors: Prior R B , Spagna V A
Published: January 2020

The Limulus amoebocyte lysate (LAL) assay was used to evaluate 115 females who were named as sexual contacts by men with culture-proven gonorrhea. These patients were treated for gonorrhea before laboratory confirmation, as recommended by the Centers for Disease Control, because of the lack of rapid screening tests and the serious consequences of undetected infection. For the LAL assay, endocervical samples were collected with depyrogenated cotton-tipped swabs, and the swabs were placed in 10 ml of diluent to assay for endotoxin; the negative predictive value of the LAL assay at this dilution was 100%. Incubation was carried out at 37 degrees C for 30 min; positive or negative results were indicated by gelation or lack of gelation, respectively. Lysate sensitivity was 0.3 ng/ml, with an Escherichia coli endotoxin standard. Single endocervical cultures and the LAL assay were both positive in 71 patients, but the Gram stain was positive in only 36 (50.7%) of these cases. For the 44 culture-negative cases, the LAL assay was negative in 21 (47.7%). Thus, the LAL assay was able to selectively exclude approximately half of the culture-negative gonorrhea contacts and would have spared these patients inappropriate therapy and contact tracing, without excluding culture-positive gonorrhea cases.
Detection of heat-labile-enterotoxin-producing colonies of Escherichia coli and Vibrio cholerae by solid-phase sandwich radioimmunoassays
Authors: Shah D B , Kauffman P E , Boutin B K , Johnson C H
Published: January 2020

A solid-phase sandwich assay that was able to differentiate heat-labile-enterotoxin-producing colonies of Escherichia coli and choleratoxin-producing colonies of Vibrio cholerae from nontoxigenic colonies is described. Flexible polyvinyl chloride plastic film coated with antibody molecules was allowed to react with partially lysed bacterial colonies in a standard petri dish. The immobilized antigen on the plastic film was then labeled with radioiodinated antibody. Autoradiography identified antigen-containing colonies. As little as 5 to 25 pg of pure toxin contained in a 3- to 4-mm-diameter circle was reliably detected by this method. The synthesis of heat-labile enterotoxin and choleratoxin by cells growing on selective media such as eosin methylene blue agar, MacConkey agar, Endo agar, and thiosulfate-citrate-bile salts-sucrose agar was demonstrated. The method appears to be suitable for large-scale surveys.
Mycoplasma hominis septicemia
Authors: DeGirolami P C , Madoff S
Published: January 2020

We report a case of Mycoplasma hominis septicemia in a patient with chronic lymphocytic leukemia and prostatic obstruction. Signs of sepsis followed urinary catheterization, and M. hominis was recovered repeatedly from blood, urine, and pleural fluid. Detection in blood was accomplished by routine subculture from grossly negative blood culture bottles.
Comparison of six different criteria for judging the acceptability of sputum specimens
Authors: Wong L K , Barry A L , Horgan S M
Published: January 2020

A series of 391 unselected expectorated sputum specimens was examined microscopically, and six different published criteria for judging the acceptability of the specimens were applied. Of the 391 specimens, 234 were found to be acceptable or unacceptable by all six criteria; 157 specimens were discrepant. By the criteria of Murray and Washington and of Barry, 25 and 23% of the specimens, respectively, were rejected; only 19 of 143 specimens which contained potential pathogens as part of their predominant microbial flora were rejected by both sets of criteria. The criteria described by Geckler et al. and Bartlett missed fewer potential pathogens; only 9 or 17% of the specimens, respectively, were found unacceptable. The criteria of Heineman and Radano and of Van Scoy resulted in the greatest percentages of specimens judged unacceptable (28 and 29%, respectively), including 19 and 24% of specimens containing potential pathogens. The reproducibility of sputum screening results was also assessed, comparing the method of Murray and Washington with that of Barry. Six separate slides were prepared from each of 45 different specimens: three samples with purulent or bloody flecks and three samples in which the specimens had been mixed with an applicator swab. Satisfactory reproducibility was observed with both criteria and both sampling methods; no significant differences in reproducibility could be documented in this limited series.
Primary culture media for routine urine processing
Authors: Fung J C , Lucia B , Clark E , Berman M , Goldstein J , D'Amato R F
Published: January 2020

It has been recommended that routine microbiological processing of urine specimens include quantitative plating onto blood agar medium along with a selective and differential agar such as MacConkey agar for gram-negative organisms. Few data have been published to justify this combination. To evaluate the validity of this recommendation 2,553 midstream, clean-voided urine samples were quantitatively plated onto blood agar, MacConkey agar, and colistin-nalidixic acid agar, which is a selective medium for gram-positive organisms. The amounts of growth on each of the three media were compared. Results indicated that the best medium combination was colistin-nalidixic acid agar and MacConkey agar. The use of colistin-nalidixic acid agar instead of blood agar increased the detection of significant growth of enterococci, lactobacilli, and Torulopsis glabrata.
Survey of the extrachromosomal gene pool of Clostridium difficile
Authors: Muldrow L L , Archibold E R , Nunez-Montiel O L , Sheehy R J
Published: January 2020

Pseudomembranous colitis, a severe diarrheal disease, has been linked to the administration of antibiotics and to two toxins produced by Clostridium difficile. Eighty-two strains of C. difficile isolated from humans and hamsters were assayed for the presence of plasmid DNA. Agarose gel electrophoresis of Sarkosyl-lysed cells indicated that 18% of the strains contained from one to four plasmids. The plasmid DNA in these strains ranged in molecular weight from 2.7 X 10(6) to 60 X 10(6). Strains with and without plasmids were examined for the cytopathogenic effect of the toxins on MRC-5 cells. No correlation was observed between plasmid content and cytopathogenic effect. The results of in vitro antibiotic susceptibility testing with plasmid-containing strains revealed that 33% of the strains tested exhibited growth with four or more of the antimicrobial agents used.
Rapid processing of urine specimens by urine screening and the AutoMicrobic system
Authors: Wadke M , McDonnell C , Ashton J K
Published: January 2020

A total of 1,500 clean-voided urine specimens were analyzed for the presence of bacteria by urine screening with the Autobac 1 system. The specimens found positive by this method were further processed on the same day for identification and for antimicrobial susceptibility testing on the AutoMicrobic system with the Enterobacteriaceae-plus Card and the General Susceptibility Card, respectively. The inocula for these tests were prepared from the centrifuged and washed growth in the eugonic broth aspirated from the Autobac cuvette chambers. Of 1,500 specimens that were analyzed, 183 contained single isolates of gram-negative bacilli. The results of these rapid procedures were compared with results for the same organisms isolated from urine specimens cultured by the conventional method. The data showed 92.3% agreement for identification and a correlation of 93.6% for antibiotic susceptibility between the two procedures. It is concluded that gram-negative bacilli can be rapidly identified and tested for antimicrobial susceptibility with a high degree of accuracy from the centrifuged eugonic broth after urine screening. These findings also suggest that the AutoMicrobic system provides a rapid and convenient method for same-day processing of positive urine cultures when combined with the urine screening procedure.
Phenotypic differences among clinically isolated mucoid Pseudomonas aeruginosa strains
Authors: Pugashetti B K , Metzger H M , Vadas L , Feingold D S
Published: January 2020

Mucoid strains of Pseudomonas aeruginosa isolated from patients with cystic fibrosis or urinary tract infections displayed many phenotypic differences. The ratios of D-mannuronosyl to L-guluronosyl moieties of the extracellular alginate-like polysaccharides produced by the 19 strains examined varied from 99 to 0.8; the acetyl content of the polymers varied from 0.38 to 0.02 mol per mole of uronosyl residue. The strains also differed with regard to the stability of the mucoid phenotype. Of 15 isolates from patients with cystic fibrosis, 7 displayed stable mucoid phenotypes; 8 isolates were unstable and reverted to the nonmucoid phenotype at high frequency. The four strains isolated from patients with urinary tract infections were also unstable. Strains from urinary tract infections expressed the mucoid phenotype on six different media, both minimal and complex, whereas cystic fibrosis-associated strains varied widely with regard to medium-dependent expression of the mucoid phenotype. Of 15 cystic fibrosis strains, 5 were mucoid on each of six different media, 4 were mucoid on five media, 1 was mucoid on four media, 4 were mucoid on three media, and 1 yielded mucoid colonies on only one of the six media tested. There was no obvious correlation among polysaccharide structure, stability of the mucoid phenotype, and medium-dependent expression of the mucoid phenotype for any of the 19 strains investigated. These data suggest that although mucoid strains of P. aeruginosa must share some common property related to their ability to colonize their host, this property seems to be unrelated to polysaccharide composition, medium-dependent expression of the mucoid phenotype, or stability of the mucoid phenotype.
Vibrio cholerae O1 isolated in Kenya
Authors: Iwanaga M , Mori K , Kaviti J N
Published: January 2020

Biological and serological analyses of 272 isolates of Vibrio cholerae O1 from six epidemics and from a few sporadic cases in Kenya were carried out. All of the isolates were identified as V. cholerae biotype E1 Tor, and 210 out of 272 isolates were hemolytic as examined by Feeley's method.
Comparison of commercially available New York City medium and Martin-Lewis medium for recovery of Neisseria gonorrhoeae from clinical specimens
Authors: Lawton W D , Koch L W
Published: January 2020

In 100 clinical specimens containing Neisseria gonorrhoeae, commercially prepared New York City medium in JEMBEC plates was superior to Martin-Lewis medium for recovery of gonococci in 49 specimens, equal to Martin-Lewis medium in 43 specimens, and less effective in 8 specimens.
Chronic granulomatous disease: fatal septicemia caused by an unnamed gram-negative bacterium
Authors: Seger R A , Hollis D G , Weaver R E , Hitzig W H
Published: January 2020

A 2-year-old boy with proven X-linked chronic granulomatous disease was placed under continuous co-trimoxazole prophylaxis. He remained free of infection for 4 years. At age 6.25 years, he suddenly developed a fever with no localizing signs and died 16 days later in septic shock. A gram-negative, catalase-positive, halophilic, aerobic bacterium was cultured from blood, bone marrow, and ascitic fluid. This organism could not be identified in microbiological laboratories in Europe and the United States. Its biochemical features indicate that it may belong to a species which has not previously been described.
Pseudomonas aeruginosa and Klebsiella pneumoniae on the perinea of males with spinal cord injuries
Authors: Gilmore D S , Schick D G , Montgomerie J Z
Published: January 2020

Pseudomonas aeruginosa colonization is found in a high percentage of males with spinal cord injury. The perineum is the body site most frequently colonized, and specific serotypes may persist for weeks. We examined patients for the presence of P. aeruginosa and Klebsiella pneumoniae on the perineum and adjacent body sites by using contact plates. P. aeruginosa, K. pneumoniae, or both were cultured from perineal swabs of 22 male patients. Wells (2.5 cm2) containing agar medium selective for these organisms were used to examine samples from 32 sites adjacent to the perineum in each patient. P. aeruginosa was most frequently cultured from samples taken from the perineum, the scrotum, and the penile shaft. K. pneumoniae isolation was more variable; this organism was most commonly found on the perineum and scrotum. Rectal swabs, obtained through a proctoscope, were positive for P. aeruginosa in four of eight patients with this organism on the perineum and positive for K. pneumoniae in eight of nine patients with this organism on the perineum. These studies more clearly define the extent of the colonization of the perineum and adjacent body sites which provides potential reservoirs of P. aeruginosa and K. pneumoniae.
Comparison of the Raji cell line fluorescent antibody to membrane antigen test and the enzyme-linked immunosorbent assay for determination of immunity to varicella-zoster virus
Authors: Iltis J P , Castellano G A , Gerber P , Le C , Vujcic L K , Quinnan G V
Published: January 2020

A prospective study was performed comparing the fluorescent antibody to membrane antigen (FAMA) test and the enzyme-linked immunosorbent assay (ELISA) for identifying susceptibility and seroconversion to varicella-zoster virus (VZV) infection. A total of 75 sera were collected from index cases and from sibling and parent contacts in 10 families. Varicella-zoster virus-infected human diploid embryonic fibroblasts and continuous lymphoblastoid cells (Raji cells) were compared as indicator cells in the FAMA test. Equivalent results were obtained with both types of cell. Results of the FAMA test and the ELISA were identical in two ways. (i) The same 11 individuals were initally defined as susceptible (seronegative), and 9 of them (82%) developed fourfold rises in antibody titers, clinical varicella, or both. (ii) Of 21 immune (seropositive) individuals, 4 developed fourfold antibody rises by FAMA tests, and 3 of these 4 responded by ELISA. Infection was asymptomatic in these individuals. The geometric mean titer by ELISA was significantly higher than by the FAMA test. The results indicated that the ELISA and the FAMA test have similar capacities to define susceptibility to varicella-zoster virus and that subclinical infection with varicella-zoster virus may be common.
Evaluation of Bactogen and Phadebact for detection of Haemophilus influenzae type b antigen in cerebrospinal fluid
Authors: Welch D F , Hensel D
Published: January 2020

Latex agglutination and coagglutination tests are commercially available as Bactogen and the Phadebact Haemophilus Test, respectively. We evaluated both for the detection of Haemophilus influenzae type b in cerebrospinal fluids. Both tests were positive in all of 51 culture-positive cases of meningitis caused by H. influenzae. Both were more sensitive than counterimmunoelectrophoresis. Antigen was also detected by Bactogen in seven of seven additional cerebrospinal fluid specimens (compared with four of seven by Phadebact) after 1 to 15 days of antimicrobial therapy. The cerebrospinal fluid of infants with meningitis owing to other common causative agents did not react with Bactogen or Phadebact. However, the cerebrospinal fluid of one patient with overwhelming infection owing to Proteus mirabilis reacted positively with Bactogen. Cost analysis revealed that Phadebact was less expensive to perform than Bactogen.
Solid-phase radioimmunoassay for detection of plague antigen in animal tissue
Authors: Soergel M E , Schaffer F L , Blank H F
Published: January 2020

A rapid and sensitive radioimmunoassay for the detection of soluble Yersinia pestis fraction I antigen using antibody-coated beads and radiolabeled immunoglobulin was applied to spleen-liver extracts, rendered noninfectious by either treatment or filtration, from rodents dead of plague. The procedure was capable of detecting nanogram amounts of soluble plague antigen.
Specificity of the latex test for cryptococcal antigen: a rapid, simple method for eliminating interference factors
Authors: Stockman L , Roberts G D
Published: January 2020

An enzymatic method involving a protease (pronase) for the elimination of interference factors in the latex test for cryptococcal antigen was developed and compared with dithiothreitol treatment. The two were equivalent in their ability to remove interference factors; however, the enzymatic method generally yielded higher titers. The method is simple, requires only 20 min, and makes the latex test for cryptococcal antigen specific.