bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical significance of Aeromonas species isolated from patients with diarrhea
Authors: Moyer N P
Published: January 2020

A total of 248 strains of Aeromonas spp. were isolated from 3,334 human fecal specimens submitted to a state public health laboratory over a 2-year period to be cultured for enteric pathogens. Cary-Blair transport medium, blood ampicillin agar, and alkaline peptone water enrichment provided optimal recovery of Aeromonas spp. A questionnaire requesting clinical and epidemiological information was sent to physicians, who submitted stool samples for testing, with each laboratory report for 107 consecutive stool isolates of Aeromonas spp. The 56 questionnaires which were completed and returned were analyzed to determine the seasonal distribution of illness and the age and sex distribution of patients; characteristic symptoms; and predisposing factors for gastrointestinal disease caused by Aeromonas spp. It was concluded that some A. hydrophila, A. sobria, and A. caviae strains are capable of causing diarrhea and that antibiotic therapy and the drinking of untreated water are significant risk factors for susceptible hosts.
Comparison of five assays for antibody to varicella-zoster virus and the fluorescent-antibody-to-membrane-antigen test
Authors: Larussa P , Steinberg S , Waithe E , Hanna B , Holzman R
Published: January 2020

Three commercially available assays (the Varicelisa Test Kit [Whittaker M.A. Bioproducts, Walkersville, Md.], the VZV Indirect Fluorescent-Antibody Test [Electro-Nucleonics, Inc., Columbia, Md.], and the Litton VZV Bio-EnzaBead Screen Kit [Litton Bionetics, Inc., Charleston, S.C.]) and two enzyme-linked immunosorbent assays used in our laboratory, one using a membrane-associated antigen and the other using a soluble antigen dotted on nitrocellulose paper, were compared with a varicella-zoster virus antibody reference assay, the fluorescent-antibody-to-membrane-antigen test. All of the assays compared favorably to the fluorescent-antibody-to-membrane-antigen test when evaluated for sensitivity (0.95), specificity (0.84), and test-retest reliability (79 to 96%), except for the Litton assay, which demonstrated significantly different results for all of the parameters tested (0.55, 1.0, and 69%, respectively).
Soluble Plasmodium falciparum antigens contain carbohydrate moieties important for immune reactivity
Authors: Jakobsen P H , Theander T G , Jensen J B , Mølbak K , Jepsen S
Published: January 2020

The importance of carbohydrate moieties for the antigenicity of purified soluble Plasmodium falciparum antigens from the asexual blood stage was tested. Digestion of the soluble antigens with alpha-D-galactosidase clearly affected the ability of the antigen to react with malaria-immune sera from different geographical origins in crossed immunoelectrophoresis and immunoblotting. Antigens of 220, 180, 80, and 74 kilodaltons were affected by the enzyme treatment. Furthermore, the enzyme digestion reduced the ability of the purified soluble antigen to stimulate lymphocytes from malaria-immune donors. The results might have important implications for the strategy of developing a malaria vaccine.
Pathogenicity test for Listeria monocytogenes using immunocompromised mice
Authors: Stelma G N , Reyes A L , Peeler J T , Francis D W , Hunt J M , Spaulding P L , Johnson C H , Lovett J
Published: January 2020

The lethality of Listeria isolates was determined with normal adult mice and mice that were immunocompromised by treatment with 20 mg of carrageenan per kg. The mean 50% lethal doses (LD50s) of the pathogenic isolates were significantly lower (alpha = 0.05) in the immunocompromised mice than in the untreated mice, with an average reduction of 5.8 log10 units. In contrast, the mean LD50s of the nonpathogenic isolates were lower in the immunocompromised mice by an average of only 0.4 log10 unit, a difference that was not significant (alpha = 0.05). When immunocompromised mice were used, the LD50s of pathogenic Listeria monocytogenes isolates were lower than those of nonpathogenic L. innocua and L. seeligeri isolates by greater than or equal to 6 log10 units and lower than those of nonpathogenic L. ivanovii isolates by greater than or equal to 4 log10 units. Pathogenic L. monocytogenes isolates could be distinguished from nonpathogenic isolates by their ability to cause deaths in immunocompromised mice in 3 days at a dose of approximately 10(4) CFU per mouse. An alternative procedure using iron-overloaded mice failed to effectively differentiate pathogenic Listeria isolates.
Rapid identification of smooth Brucella species with a monoclonal antibody
Authors: Roop R M , Preston-Moore D , Bagchi T , Schurig G G
Published: January 2020

A colony blot enzyme-linked immunosorbent assay was developed for the rapid identification of smooth Brucella species, i.e., Brucella abortus, B. melitensis, and B. suis. Bacterial colonies from plates were blotted onto nitrocellulose disks, lysed by immersion in chloroform, and reacted with BRU 38, a rat monoclonal antibody with specificity for the O side chain of B. abortus. Reaction with anti-rat immunoglobulin G conjugated to horseradish peroxidase and development in 4-chloro-1-naphthol resulted in colonies of naturally occurring smooth Brucella species staining purple. Results could be obtained within 4 h after colonies were visible on plates and individual colonies could be detected. Yersinia enterocolitica serovar O:9 strains were the only other organisms tested which showed cross-reaction by using this procedure. Because of its speed, sensitivity, and specificity, this technique should be very useful for identifying smooth Brucella strains in diagnostic laboratories.
Growth of Campylobacter pylori in liquid media
Authors: Morgan D R , Freedman R , Depew C E , Kraft W G
Published: January 2020

Until recently, broth cultivation techniques for Campylobacter pylori were unavailable. We developed a method to cultivate bacterial cells within 24 h in liquid media. Cultivation in broth depended on the adequate dispersion of appropriate gases. A static broth at 37 degrees C in a GasPak jar (BBL Microbiology Systems, Cockeysville, Md.) with a CampyPak (BBL) envelope did not support growth after 5 days of incubation. A broth placed in a flask on a Gyrotory water bath shaker (150 rpm; New Brunswick Scientific Co., Inc., Edison, N.J.) fitted with a gassing hood connected to a gas mixture of 10% CO2, 5% O2, and 85% N2 supported good growth. An initial inoculum of 10(5), 10(3) to 10(4), or 10(2) CFU/ml resulted in greater than or equal to 10(8) CFU/ml after incubation for 24, 48, or 72 h, respectively. Under these conditions, the bacteria grew as motile, spiral bacilli rather than the oval and coccal bacilli occasionally reported. Several bases supported good growth when supplemented with serum. For the determination of basal growth conditions, brucella broth base was used. Fetal calf serum (1%) provided maximum growth. Vitox was not necessary for growth and did not augment growth. C. pylori grew over a wide optimal pH range of 5.5 to 8.5.
Immunological cross-reactivity of a Mycoplasma pneumoniae membrane-associated protein antigen with Mycoplasma genitalium and Acholeplasma laidlawii
Authors: Cimolai N , Bryan L E , To M , Woods D E
Published: January 2020

A murine monoclonal antibody, OC2F5, reacts with a Mycoplasma pneumoniae antigen with an approximate Mr of 43,000. This antigen is trypsin and proteinase K sensitive and partitions in the detergent phase of a Triton X-114 solution. The monoclonal antibody cross-reacts with an antigen from both Mycoplasma genitalium and Acholeplasma laidlawii with a similar molecular weight. This cross-reactivity should be considered in the development of M. pneumoniae antigen detection systems based on the use of antibodies directed to this protein antigen.
Detection of Salmonella spp. in clinical specimens by capture enzyme-linked immunosorbent assay
Authors: Araj G F , Chugh T D
Published: January 2020

A capture enzyme-linked immunosorbent assay (ELISA; Kirkegaard and Perry Laboratories, Gaithersburg, Md.) was used to detect Salmonella spp. in clinical and artificially inoculated specimens. In patients with bacteremia caused by Salmonella spp., 48% (12 of 25) and 82% (13 of 16) of serum and urine specimens, respectively, were positive for Salmonella spp., as determined by ELISA. All serum and urine specimens collected from healthy individuals (25 specimens) or patients whose blood cultures grew gram-negative bacteria other than Salmonella spp. (18 specimens) were negative for Salmonella spp., as determined by ELISA. For blood culture bottles in which Salmonella spp. (16 specimens) was grown the ELISA was positive (100%), while it was negative for all the 65 blood culture bottles in which gram-negative bacteria other than Salmonella spp. (42 specimens) or gram-positive bacteria (23 specimens) were grown. All samples of urine (16 specimens), stool (8 specimens), serum (16 specimens), culture media (12 specimens), and blood culture bottles (reported sterile after 2 weeks of incubation; 16 specimens) that were artificially inoculated with 10(3) to 10(7) CFU of four species of Salmonella per ml were positive by ELISA. Similar specimens inoculated with or containing various species other than Salmonella were negative by this test. Thus, ELISA offers a promising opportunity for the rapid detection of Salmonella spp. in clinical microbiology laboratories.
Serum antibodies to outer membrane proteins of Escherichia coli in healthy persons and patients with bacteremia
Authors: Henriksen A Z , Maeland J A
Published: January 2020

Antibodies to Escherichia coli outer membrane proteins in sera from healthy persons and from patients bacteremic with various enteric or nonenteric bacteria were measured by an enzyme-linked immunosorbent assay (ELISA). Outer membranes were prepared from E. coli O55. Serum was absorbed with E. coli O55 lipopolysaccharide and diluted 1:100 for immunoglobulin A (IgA) or IgM and 1:1,000 for IgG antibodies. Paired serum specimens were obtained from the 56 patients included in the study (the first specimen on the day of positive blood culture and the second specimen 8 to 12 days later) and compared with sera from blood donors (n = 50) as controls. On an average, the patients bacteremic with enterobacteria (n = 40) showed increased levels of antibodies of all three immunoglobulin classes in the first serum specimens and significantly higher levels in the second specimens compared with the controls, although with considerable case-to-case variation. Increased levels of IgG antibodies showed the best combination of diagnostic specificity (100%) and sensitivity (53%) for bacteremia caused by enteric bacilli. Mostly, the antibody response was directed against the major E. coli O55 outer membrane proteins at 81,000, 38,500, 33,500, and 7,500 molecular weights as shown by Western blot (immunoblot) analysis. Some of the patients bacteremic with nonenteric bacteria showed increased levels of IgA antibodies, but not of IgG or IgM antibodies. Cross-reactivity of the nonenteric blood culture isolates with the E. coli outer membrane preparation was not demonstrated. The cross-reactivity of the E. coli O55 outer membrane proteins with those of enteric bacilli of other genera was examined by absorption experiments. Western blots with serum absorbed with live E. coli O55 provided evidence that the epitopes of the outer membrane protein at 7,500 molecular weight were available for antibody binding at the bacterial surface, and that at least some of the epitopes of the 38,500- and 33,500-molecular -weight proteins were accessible to antibodies. The results suggest that an ELISA for the measurement of antibodies against cross-reactive outer membrane proteins from enteric bacilli may be useful in the diagnosis of serious infections caused by members of the family Enterobacteriaceae, and that antibodies to the major outer membrane proteins may have an immunobiological function.
Specificity of skin test with varicella-zoster virus antigen in varicella-zoster and herpes simplex virus infections
Authors: Baba K , Shiraki K , Kanesaki T , Yamanishi K , Ogra P L , Yabuuchi H , Takahashi M
Published: January 2020

Specificity of the skin test with varicella-zoster virus (VZV) antigen was examined in guinea pigs infected with herpes simplex virus (HSV) type 1 or VZV and in children with a history of HSV infection who developed varicella. Infected guinea pigs responded positively only to homologous virus. No cross-reaction between HSV and VZV was detected in the skin test, as well as in the neutralization test in infected guinea pigs, suggesting that the VZV skin test is specific for immunity to VZV infection. Twelve children were infected with HSV during an HSV epidemic and subsequently developed varicella in institutional settings. During the 2.5-month period between the HSV and VZV infections, the immune status of the children to VZV was negative both in the skin test and in the antibody test, although antibody to HSV was detected by an immune adherence hemagglutination test. After VZV infection, all responded positively both in the skin test and in the antibody test (immune adherence hemagglutination test) to VZV. These results suggest that the VZV skin test is specific for immunity to VZV infection, not cross-reactive to HSV infection in humans. This specificity will be of value in screening susceptibility or immunity to VZV, irrespective of prior HSV infection.
Toxin production by Vibrio mimicus strains isolated from human and environmental sources in Bangladesh
Authors: Chowdhury M A , Aziz K M , Kay B A , Rahim Z
Published: January 2020

Vibrio mimicus has recently been isolated from aquatic environments of Bangladesh. A total of 125 of 300 environmental isolates, representing various biotypes, and 19 human isolates were tested for enteropathogenicity by using several models. Less than 1% of the environmental isolates and slightly more than 10% of the clinical isolates produced cholera toxin-like toxin. A significant percentage of the environmental isolates (25%) and of the human isolates (74%) induced fluid accumulation in ligated rabbit ileal loops. One environmental strain produced heat-stable toxin-like enterotoxin, whereas all of the human isolates did not. V. mimicus strains were divided into the following three groups on the basis of their activity in various toxin assays: (i) organisms which produce a heat-labile enterotoxin immunobiologically similar to cholera toxin, (ii) organisms which produce a heat-stable enterotoxin-like toxin, and (iii) organisms whose whole-cell cultures have some activity characteristic of heat-labile toxin (e.g., fluid accumulation in ligated rabbit ileal loops and positive permeability factor) but are not positive by the GM1 enzyme-linked immunosorbent assay. One isolate from this group was able to elicit these results with cell-free culture filtrates. There was no correlation of biotype with toxic activity of V. mimicus isolates.
Nosocomial septicemia with CDC group IV c-2, an unusual gram-negative Bacillus
Authors: Crowe H M , Brecher S M
Published: January 2020

A 55-year-old man with severe peripheral vascular disease developed nosocomial septicemia which was caused by the gram-negative bacterium CDC group IV c-2, presumably from a plantar abscess on the left foot. Recovery followed amputation of the infected extremity and antibiotic therapy. This is the first reported case of nosocomial acquisition of this organism.
DNA probe for detection of the Leptospira interrogans serovar hardjo genotype hardjo-bovis
Authors: LeFebvre R B
Published: January 2020

A DNA probe is described for the diagnostic and taxonomic identification of the North American cattle pathogen Leptospira interrogans genotype hardjo-bovis. The probe is specific for this genotype and does not hybridize to genomic DNA of any other leptospire pathogen commonly found in North America.
Rectal swab cultures for Clostridium difficile surveillance studies
Authors: McFarland L V , Coyle M B , Kremer W H , Stamm W E
Published: January 2020

We compared the recovery of Clostridium difficile from hospitalized patients by two collection methods: rectal swabs and stool cultures. Rectal swab cultures were as sensitive as stool cultures and were more easily obtained. Transport of swabs in an anaerobic VACUTAINER system resulted in longer survival times compared with transport in Amies medium.
Expression of type 1 fimbriae may be required for persistence of Escherichia coli in the catheterized urinary tract
Authors: Mobley H L , Chippendale G R , Tenney J H , Hull R A , Warren J W
Published: January 2020

Long-term urinary catheterization results in polymicrobial bacteriuria and is complicated by fever, bacteremia, acute pyelonephritis, and death. Escherichia coli is a common urine isolate from catheterized patients and can persist for months. We hypothesized that fimbria-mediated adherence contributes to its persistence. For 1 year, urine specimens were collected from 51 patients greater than or equal to 65 years of age who were catheterized for greater than or equal to 30 days. E. coli was isolated at greater than or equal to 10(5) CFU/ml from 447 (36%) of 1,230 weekly urine specimens from 26 patients. Week 1 isolates from 52 definable episodes were tested for hemagglutination, hybridization with gene sequences from the pil and pap operons, in vitro adherence to catheter material, binding of 125I-labeled Tamm-Horsfall protein, hemolysin and colicin V production, and serum resistance. The proportions of isolates of short (1 week only), medium (2 to 11 weeks) and long (greater than or equal to 12 weeks) episodes of bacteriuria which expressed type 1 fimbriae as assayed by mannose-sensitive hemagglutination were 59, 65, and 92%, respectively. Isolates with the pil operon (the genome for type 1 fimbriae) from episodes lasting greater than 1 week expressed mannose-sensitive hemagglutination more frequently (P = 0.011) than pil-positive isolates from episodes of less than or equal to 1 week. Isolates from episodes of greater than 1 week also bound significantly more Tamm-Horsfall protein than isolates from episodes of less than or equal to 1 week (P = 0.044). Although nearly half of the isolates produced P fimbriae, an important virulence factor for the development of pyelonephritis, no correlation with persistence could be made. Overall, the E. coli isolates expressed traits similar to those of strains that caused cystitis. Type 1 fimbriae appear to be important for the persistence of E. coli in the long-term-catheterized urinary tract.
Collagen binding in clinical isolates of Staphylococcus aureus
Authors: Holderbaum D , Spech T , Ehrhart L A , Keys T , Hall G S
Published: January 2020

Collagen binding was examined in 90 strains of Staphylococcus aureus derived from patient samples. Slightly under one-half (39 of 90) of the S. aureus strains bound collagen. Collagen binding in S. aureus did not correlate with either immunoglobulin G or fibronectin binding by these organisms. Chi-square analysis of isolates obtained from patients with complicated bacteremia (bacteremia associated with deep tissue infection) compared with isolates from patients with uncomplicated bacteremia (bacteremia without other infection) showed that the former strains were significantly more likely to have collagen-binding ability. Subcloning of primary isolates from patients with bacteremia showed that all clones from individual patients were either all positive for collagen binding or all negative, suggesting a common clonal origin for this characteristic. The ability to bind collagen could not be induced in strains lacking collagen affinity by repeated subculture in media supplemented with collagen.
Characterization of Borrelia burgdorferi strains isolated from Ixodes pacificus ticks in California
Authors: Bissett M L , Hill W
Published: January 2020

In a survey of 1,714 adult Ixodes pacificus ticks collected in northern California, 24 (1.4%) were found to be infected with spirochetes that reacted with an anti-Borrelia burgdorferi polyvalent conjugate in direct immunofluorescence tests. Eleven isolates of B. burgdorferi from these ticks were characterized by monoclonal antibody, polyacrylamide gel electrophoresis, and Western blot (immunoblot) analyses. Ten of the isolates had molecular and antigenic characteristics similar to those of other U.S. isolates. One strain, cloned by limiting-dilution techniques, was different from any previously reported U.S. strain, but similar to reported European strains. The cloned strain, DN127-Cl9-2, did not react with monoclonal antibodies to Osp A and Osp B major proteins found in most of the U.S. strains. It exhibited an abundant protein with an apparent molecular weight of 25,000.
Comparison of enzyme immunoassay and culture for diagnosis of chlamydial conjunctivitis and respiratory infections in infants
Authors: Hammerschlag M R , Roblin P M , Cummings C , Williams T H , Worku M , Howard L V
Published: January 2020

The efficacy of Chlamydiazyme (Abbott Laboratories, North Chicago, Ill.) in detecting neonatal conjunctival and respiratory infections caused by Chlamydia trachomatis was determined by comparison of this enzyme immunoassay (EIA) with the method of isolation of chlamydiae in tissue culture. The sensitivity and specificity of Chlamydiazyme for detecting C. trachomatis in conjunctival specimens from infants with conjunctivitis were 98 and 94%, respectively. For nasopharyngeal infection in infants with conjunctivitis, the sensitivity and specificity were 87 and 92%, respectively. There were nine nasopharyngeal specimens that were Chlamydiazyme positive and culture negative. All of these specimens demonstrated the presence of typical fluorescing chlamydial elementary bodies when pellets of the original specimens were examined with a fluorescein-conjugated monoclonal antibody. When the EIA was performed on nasopharyngeal specimens from infants with suspected chlamydial pneumonia, 6 culture-positive and 10 culture-negative specimens were correctly identified.
Isolation of enterotoxigenic Bacteroides fragilis from humans with diarrhea
Authors: Myers L L , Shoop D S , Stackhouse L L , Newman F S , Flaherty R J , Letson G W , Sack R B
Published: January 2020

Enterotoxigenic Bacteroides fragilis was isolated from stool specimens of 8 of 44 diarrheic individuals (ages, 4 months to 69 years). The individuals had watery diarrhea and intestinal cramping; and infants had hyperthermia, vomiting, and blood in the stools. No recognized enteric pathogens were detected in seven of the eight diarrheic individuals positive for enterotoxigenic B. fragilis. The bacterium produced an enterotoxin detectable in concentrated broth that supported bacterial growth. Fifteen adult rabbits with ligated ceca developed fatal enteric disease following intraileal injection with 5 x 10(9) CFU of enterotoxigenic B. fragilis. Conversely, eight control rabbits injected with nonenterotoxigenic B. fragilis remained clinically normal. As few as 5 x 10(3) CFU of enterotoxigenic B. fragilis caused fatal enteric disease in the rabbit model. Disease in rabbits was characterized by mucoid, often hemorrhagic, diarrhea. The bacterium colonized the caudal small intestine and the colon of the rabbits and caused moderate to severe necrotizing colitis. Enterotoxigenic B. fragilis is widespread in the intestinal tract of diarrheic humans and is enteropathogenic in adult rabbits with ligated ceca. Its possible role in the enteric disease complex merits further study.
Multicenter comparison of MicroScan and BACTEC blood culture systems
Authors: Wasilauskas B , Gay R , Zwadyk P , Pfaller M , Koontz F
Published: January 2020

Recently, MicroScan (Baxter MicroScan Div., W. Sacramento, Calif.) introduced a radiolabeled-blood-culture system that is compatible with the BACTEC 460 (Johnston Laboratories, Inc., Towson, Md.). A multicenter blood culture study was initiated to evaluate this new system. Approximately 20 ml of blood was obtained from each patient and divided equally between BACTEC and MicroScan bottles which were incubated and processed identically. Aerobic bottles were examined twice on days 1 and 2 and once on days 3, 4, 5, 6, and 7. Anaerobic bottles were examined once a day for 7 days. There were 3,451 cultures evaluated, and 414 of these subsequently grew microorganisms. Of these positive cultures, 64 were judged to be contaminated. Of the remaining 350 positive cultures, 253 grew in both systems, 54 grew in BACTEC bottles only, and 43 grew in MicroScan bottles only. The average times to detect positive cultures were 1.8 and 2.1 days by the BACTEC and the MicroScan systems, respectively. No significant difference in the number or kind of organisms recovered or in the detection times for positive cultures was observed between the two blood-culturing systems.
Evaluation of PASCO MIC-ID system for identifying gram-negative bacilli
Authors: Rhoden D L , Schable B , Smith P B
Published: January 2020

A production model of the semi-automated PASCO MIC-ID system (PASCO Laboratories, Wheat Ridge, Colo.) was evaluated with 122 groups or species of gram-negative bacilli, which included typical (499 cultures) and atypical (37 cultures) strains of fermenters and nonfermenters. The PASCO system identified 90.9% of 536 cultures accurately; these included 90.8% of 152 nonfermenters, 93.8% of 308 enteric fermenters, and 78.9% of 76 oxidase-positive fermenters. These results were obtained with the aid of serologic tests and a few additional biochemical tests, when recommended by the PASCO system. Of the 14 misidentified nonfermenters, 3 were Pseudomonas paucimobilis, 3 were Weeksella virosa (Centers for Disease Control group IIf), 2 were Xanthomonas (Pseudomonas) maltophilia, and 6 were randomly distributed among the other groups and species tested. The 19 enteric fermenters that were misidentified were randomly distributed among the groups and species tested. Of the 16 misidentified oxidase-positive fermenters, 4 were Pasteurella ureae, and 12 were randomly distributed among the other groups and species. The system identified the most commonly encountered organisms at a rate of 95% or better. The PASCO system is easy to inoculate and read. A slightly improved data base should remedy most of the identification problems.
Identification of Yersinia spp. with the API 20E system
Authors: Archer J R , Schell R F , Pennell D R , Wick P D
Published: January 2020

The ability of the API 20E system to identify 105 clinical isolates of Yersinia spp. was compared with those of conventional biochemical tests at 28 and 37 degrees C. Elimination of the Voges-Proskauer test (recorded as a negative result) increased the percentage of correct identifications for Yersinia spp. from 66 to 93% when the API 20E strips were incubated at 28 degrees C.
Spondylitis and osteomyelitis caused by Kingella kingae in children
Authors: Chanal C , Tiget F , Chapuis P , Campagne D , Jan M , Sirot J
Published: January 2020

Two cases of documented osteoarticular infections caused by Kingella kingae in children are reported. The main bacteriological characteristics and antibiotic susceptibilities of these two isolates are described. The pathology of K. kingae, particularly in bones and joints, is reviewed.
Collaborative clinical laboratory evaluation of an individual MIC strip system
Authors: Isenberg H D , D'Amato R F , McKinley G A , Green L H , Canonica F P , Fredericks L M , Hochstrasser J M , Giugliano E R , Alperstein P , France K
Published: January 2020

Susceptibility results obtained with individualized MIC strips (MICRO-MIC) agreed with the standard microdilution broth method at a level of 96% or greater for each of the 10 antimicrobial agents tested.
Evaluation of rapid SYS system as screen for Yersinia enterocolitica in the United States
Authors: Mele L , Nadler H , Gomez S
Published: January 2020

Clinical isolates (n = 150) from stool specimens were selected for evaluation of the Rapid SYS system (Analytab Products, Plainview, N.Y.) as a screening test for Shigella spp., Yersinia enterocolitica, and Salmonella spp. The Gram-Negative Identification Card (Vitek Systems, Inc., Hazelwood, Mo.) was used for identification. Although acceptable performance of the Rapid SYS system was described, the interpretative criteria provided by the vendor for previous studies led to inappropriate screening for Y. enterocolitica, particularly biotype 1. When corrected screening criteria were used for the present study, the sensitivity for the detection of 76 enteric pathogens was 98.7%. Of the 76 pathogens, 1 of 21 Shigella spp. was not detected. However, specificity was only 16.6% when 72 selected nonpathogens frequently encountered in stools were eliminated. Although the Rapid SYS system can identify Shigella spp., Y. enterocolitica, and Salmonella spp., only phenylalanine deaminase-producing and cytochrome oxidase-producing organisms can be eliminated from additional testing. Therefore, the Rapid SYS system cannot be used as a three-pathogen screen in the United States or in other geographic locales where Y. enterocolitica biotype 1 may be encountered.
Umbelliferyl-labeled galactosaminide as an aid in identification of Candida albicans
Authors: Perry J L , Miller G R
Published: January 2020

The initial evaluation of a fluorescence, nonmicroscopic method of rapid identification of Candida albicans is described. A total of 524 yeast isolates were evaluated in parallel by the umbelliferyl-conjugated N-acetyl-beta-D-galactosaminide (UAG) test and the germ tube (GT) test in comparison with the API 20C Yeast Identification System. The UAG test correctly identified 333 of the 334 isolates of C. albicans (99.7%), and the GT test identified 328 (98%). There were three false-positive GT reactions and five false-positive UAG reactions with 69 isolates of C. tropicalis. The sensitivity and specificity were 99 and 97%, respectively, for the UAG test and were both 98% for the GT test. The UAG test requires less than 2 h for test completion compared with 2 to 4 h for the GT test, is similar in cost, has a nonmicroscopic visual endpoint, and eliminates the health hazards of handling pooled human sera.
Production and characterization of neutralizing monoclonal antibody to a human rotavirus strain with a "super-short" RNA pattern
Authors: Tursi J M , Albert M J , Bishop R F
Published: January 2020

A neutralizing monoclonal antibody, B37:1, against a human rotavirus (B37) with a "super-short" RNA pattern was derived. The antibody gave serotype-specific reactions with a panel of standard rotaviruses and was reactive in an enzyme immunoassay. Epidemiological studies of this new human serotype should now be possible.
Identification of Haemophilus influenzae type b by a monoclonal antibody coagglutination assay
Authors: Hamel J , Brodeur B R , Belmaaza A , Montplaisir S , Musser J M , Selander R K
Published: January 2020

A coagglutination assay using monoclonal antibody is described for the identification of Haemophilus influenzae type b. An immunoglobulin G2a monoclonal antibody, Hb-2, directed against a serotype-specific outer membrane protein of H. influenzae type b was adsorbed to Staphylococcus aureus Cowan 1 cells. In a dot enzyme immunoassay, Hb-2 reacted with 453 of 455 H. influenzae type b isolates and did not react with H. influenzae of other serotypes, untypeable H. influenzae strains, or other bacterial species. The Hb-2 coagglutination assay was evaluated by testing 136 H. influenzae type b strains selected on the basis of multilocus enzyme genotypes, 5 strains of another serotype, and 94 untypeable H. influenzae strains. The specificity of the coagglutination assay was demonstrated by the inhibition of the reaction by free Hb-2 monoclonal antibodies. The coagglutination assay was as specific as the dot enzyme immunoassay and can be rapidly performed and easily interpreted.
Single-concentration broth microdilution test for detection of high-level aminoglycoside resistance in enterococci
Authors: Zervos M J , Patterson J E , Edberg S , Pierson C , Kauffman C A , Mikesell T S , Schaberg D R
Published: January 2020

Growth in a single broth microdilution well containing gentamicin at a concentration of 500 micrograms/ml predicted high-level resistance to gentamicin (MIC, greater than or equal to 2,000 micrograms/ml) in 505 of 508 clinical isolates of enterococci. Failure to achieve synergistic killing with the combination of penicillin and an aminoglycoside was demonstrated with 100% specificity in 20 strains which showed resistance to 500 micrograms of gentamicin per ml. We recommend this procedure be adopted as a routine screening test to detect high-level aminoglycoside resistance in enterococci.
Arthritis caused by Haemophilus paraphrophilus and isolation of the organism by using an improved culture protocol
Authors: von Essen R , Kostiala A A , Anttolainen I , Haapasaari J , Sivonen A
Published: January 2020

A case of bacterial arthritis caused by Haemophilus paraphrophilus is presented. This is the first reported case of arthritis caused by this organism. Culturing joint fluid in blood culture bottles provides for bacteria that are slow growing or present in small numbers.
Indirect immunofluorescence assay for antibodies to human immunodeficiency virus
Authors: Lennette E T , Karpatkin S , Levy J A
Published: January 2020

We compared an indirect immunofluorescence assay (IFA) with a commercial enzyme-linked immunosorbent assay (ELISA) screening procedure for the detection of antibodies to the human immunodeficiency virus (HIV). The IFA assay was as sensitive and specific as the ELISA. No false results were observed with IFA on single testing of 181 sera, while the ELISA produced five false-positive results which required retesting for resolution. In addition, the IFA was suitable for quantitation of anti-HIV responses. The IFA was superior to the ELISA for its reliability, simplicity, and rapidity in the diagnostic laboratory.
Serodiagnosis of Streptococcus faecalis endocarditis by immunoblotting of surface protein antigens
Authors: Aitchison E J , Lambert P A , Smith E G , Farrell I D
Published: January 2020

We describe a method for the serodiagnosis of Streptococcus faecalis in infective endocarditis which could be of value in culture-negative cases. Serum-grown cells of S. faecalis produced three major characteristic protein antigens (73,000, 40,000, and 37,000 molecular weight) which were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of solubilized whole cells. After electrophoretic transfer to a nitrocellulose membrane, these antigens were visualized by probing with serum from patients with endocarditis caused by S. faecalis. Serum from patients with endocarditis caused by other organisms did not react with the S. faecalis-specific antigens. This procedure should facilitate positive early diagnosis of S. faecalis endocarditis or establish its absence in culture-negative cases.
Diagnosis of pneumococcal pneumonia by enzyme-linked immunosorbent assay of antibodies to pneumococcal hemolysin (pneumolysin)
Authors: Kalin M , Kanclerski K , Granström M , Möllby R
Published: January 2020

An enzyme-linked immunosorbent assay (ELISA) with a highly purified pneumolysin as the antigen was evaluated for serological diagnosis of pneumococcal pneumonia. One hundred four healthy controls were tested, and the specificity of the test was set to 95%. In samples from patients with bacteremic pneumococcal pneumonia, 82% (18 of 22) were positive, i.e., at least one serum sample had a titer above the upper normal limit or at least a twofold rise in antibody titers was noted. In nonbacteremic pneumococcal pneumonia, 45% (21 of 47) of samples were positive. All sera were negative for patients with pneumonia caused by Haemophilus influenzae, Legionella pneumophila, Chlamydia psittaci, and influenza A virus. However, in patients with a diagnosis of Mycoplasma pneumoniae infection, 8 of 25 (32%) samples were positive for antibodies to pneumolysin. All sera, including those from patients with mycoplasma infection, were negative to a protein control antigen by ELISA. Serum immunoglobulin G response to pneumolysin as measured by ELISA might thus be an aid in the laboratory diagnosis of pneumococcal pneumonia. This assay may also help to further elucidate the occurrence of dual infections with pneumococci.
Isolation of immunodominant antigens from sera of patients with systemic candidiasis and characterization of serological response to Candida albicans
Authors: Matthews R C , Burnie J P , Tabaqchali S
Published: January 2020

Candidal antigens were isolated by affinity chromatography from the sera of patients with disseminated Candida albicans infections. The immunodominant 47-kilodalton (kDa) antigen appeared to be a heat-stable breakdown product of several larger heat-labile components (84 to 92, 74 to 79, and 66 to 72 kDa). It was undetectable in normal sera and sera from four patients with systemic C. parapsilosis, C. tropicalis, and C. krusei infections. Serum samples from 92 patients with proven systemic C. albicans infections were examined by the immunoblot technique. Seventy-four patients had detectable antibody, and 92% of these produced antibody to the 47-kDa antigen. All survivors had major serological responses to this antigen, whereas patients who died had no, minor, or fading responses. Fifty-five of the patients were neutropenic following cytotoxic chemotherapy for malignancies, usually lymphoproliferative disorders (hematological patients). The remainder were surgical or medical patients (nonhematological). Hematological patients differed from nonhematological patients in the range of antigens that were commonly recognized by their immune systems, although antibodies to the 47- and 60-kDa antigens were frequently present in both groups. They also differed in that they produced mainly an immunoglobulin M (IgM) response, failing to seroconvent to IgG. This did not reduce survival rates, which were similar in both groups. It may be responsible, however, for the lower antigen titers that were observed in hematological patients when measured by reverse passive latex agglutination.
Detection of immunoglobulin G to Pasteurella haemolytica capsular polysaccharide by enzyme-linked immunosorbent assay
Authors: Townsend E L , Maheswaran S K , Leininger J R , Ames T R
Published: January 2020

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of immunoglobulin G (IgG) to the capsular polysaccharide (CP) of Pasteurella haemolytica serotype 1. Purified CP was first covalently coupled to poly-L-lysine and then optimally adsorbed at a concentration of 5 micrograms/ml to microtiter plates in the presence of carbonate-bicarbonate buffer (pH 9.8). The ELISA was used to evaluate and compare the CP-specific IgG response of calves vaccinated with different P. haemolytica-derived experimental vaccines. Elevated levels of ELISA IgG titers were detected in postvaccination sera and lung lavage from calves vaccinated intradermally with live logarithmic-phase organisms or the culture supernatants. The ELISA was found to be a rapid, reproducible, and sensitive technique for the detection of CP-specific antibodies and may be useful to delineate the protective role of these antibodies in bovine pneumonic pasteurellosis.
Propionibacterium acnes osteomyelitis: case report and review of the literature
Authors: Noble R C , Overman S B
Published: January 2020

Propionibacterium acnes, a part of the skin flora, caused vertebral osteomyelitis in a man who had recently undergone a microdiskectomy. The identifying characteristics and antibiotic susceptibility pattern are presented for this unusual human pathogen. The relationship of P. acnes to bone infection is summarized for the first time. A typical patient with P. acnes osteomyelitis is an adult male who has had prior surgery. Most patients respond favorably to prolonged antibiotic therapy.
Physicochemical characterization of porcine pararotavirus and detection of virus and viral antibodies using cell culture immunofluorescence
Authors: Terrett L A , Saif L J , Theil K W , Kohler E M
Published: January 2020

A cell culture immunofluorescence (CCIF) assay was optimized for detection of porcine pararotavirus (group C rotavirus) in intestinal contents. The greatest viral infectivity was observed when MA104 cells (5 days after subculturing) were rinsed and refed in serum-free medium before inoculation, pancreatin was added to the inocula, and the inocula were centrifuged onto the cells. Gentamicin treatment of pararotavirus samples to reduce bacterial contamination also reduced the viral infectivity of these samples for MA104 cells. An indirect CCIF assay was used to determine the prevalence of pararotavirus and rotavirus antibodies in pig sera. In pigs from four herds, pararotavirus antibodies were detected in 100% (68 of 68) of adults and 59% (24 of 41) of weanling pigs, while 86% (24 of 28) of nursing pigs from 12 herds had pararotavirus antibodies. The physicochemical properties of pararotavirus were examined and compared with those of group A rotaviruses by using the CCIF assay to quantitate in vitro changes in viral infectivity. Pararotavirus was inactivated (greater than or equal to 99% reduction in titer) by heating to 56 degrees C for 30 min, was slightly labile at pH 3 (16 to 34% reduction in titer), and was stable at pH 5 (0 to 17% reduction in titer) and in either (3 to 19% reduction in titer). One group A rotavirus (Gottfried strain) was stable at 56 degrees C (0% reduction in titer), whereas the OSU strain of group A rotavirus was inactivated at this temperature (99% reduction in titer).
Enzyme-linked immunosorbent assay for detection of Salmonella typhi protein antigen
Authors: Appassakij H , Bunchuin N , Sarasombath S , Rungpitarangsi B , Manatsathit S , Komolpit P , Sukosol T
Published: January 2020

A double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) was designed for the detection of Salmonella typhi protein antigen. The optimal concentration of antibody for coating the plate was found to be 50 micrograms/ml. The optimum conditions for antibody coating and antigen and conjugate incubation were 37 degrees C for 3 h, 37 degrees C for 2 h, and 4 degrees C overnight, respectively. The enzyme-substrate reaction was allowed to take place at 30 degrees C for 1 h. The established ELISA was found to be reproducible, with an inter-run coefficient of variation of less than 12% for the detection of an S. typhi protein antigen concentration of 0.5 to 50 micrograms/ml. The minimal detectable level of the antigen was 0.5 micrograms/ml. Cross-reactions were observed with the high level (50 micrograms/ml) of protein antigens obtained from Salmonella typhimurium, Escherichia coli, Salmonella paratyphi A, and Salmonella enteritidis. The ELISA established was used for the detection of S. typhi protein antigen in serum from 62 patients with typhoid, 30 patients with clinically diagnosed typhoid fever, 21 patients with paratyphoid, 17 patients with pyrexia caused by other bacteria, and 160 normal, healthy individuals. It was found that the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of this assay were 83.87, 89.04, 87.93, 67.53, and 95.31%, respectively.
Prevalence of antibody to group B (atypical) rotavirus in humans and animals
Authors: Brown D W , Beards G M , Chen G M , Flewett T H
Published: January 2020

Enzyme-linked immunosorbent assays were developed for the detection of group B rotavirus antigen and antibody. The specificities of both assays were evaluated for antigens and serum specific for rotavirus groups A to D. Serum collected in the United Kingdom from different animal species exhibited the following high prevalence of group B rotavirus-specific antibody: pigs, 97%; cattle, 71%; sheep, 91%; and goats, 91%. In human serum, a lower prevalence of group B-specific antibody was detected; serum from blood donors showed 10% prevalence, and serum from veterinarians showed 4% prevalence.
Capillary enzyme immunoassay for rapid detection of herpes simplex virus in clinical specimens
Authors: Shekarchi I C , Fuccillo D A , Strouse R , Sever J L
Published: January 2020

Capillary enzyme immunosorbent assay (CapELISA) is a modification of the standard enzyme immunosorbent assay which permits rapid detection of viral antigens in clinical specimens. The capillary tube format provides a very large reactive surface relative to the sample size. The close proximity of antigen to antibody in the tube optimizes the reaction, resulting in increased sensitivity and shorter incubation requirements. Sensitivity is further enhanced by use of a biotin-avidin enzyme detector system and a fluorogenic rather than a colorigenic substrate. The assay is performed at ambient temperature and requires less than 2 h. It is read with an inexpensive hand-held black light. Data for the use of CapELISA for the detection of herpes simplex virus in clinical specimens are presented. The results show greater than or equal to 85% sensitivity and 100% specificity when compared with tissue culture tests on the same samples. This new system should be advantageous for the diagnosis, treatment, and management of patients with herpesvirus infections and for the prevention of neonatal herpes acquired by passage of the fetus through an infected birth canal.
Detection of St. Louis encephalitis virus antigen in mosquitoes by capture enzyme immunoassay
Authors: Tsai T F , Bolin R A , Montoya M , Bailey R E , Francy D B , Jozan M , Roehrig J T
Published: January 2020

Surveillance methods that measure St. Louis encephalitis (SLE) virus activity in nature may provide forewarning of its epidemic occurrence in humans. An antigen capture enzyme immunoassay was developed to detect SLE virus in infected mosquitoes. The assay detected purified SLE viral antigen at a concentration of 62 pg/0.1 ml when antigen was incubated overnight; 250 pg/0.1 ml was detected in a single-day assay (antigen incubated for 3 h). The assay detected 67.9 and 70.8% of laboratory-prepared pools of infected mosquitoes after 3 h and overnight incubation, respectively. The sensitivity of the procedure was 90.5% in identifying pools with infectious titers greater than dex 3.0. The specificity of the assay was controlled by retesting positive pools preincubated with SLE virus and normal antibodies, which led to a diminution of signal in the pools containing viral antigen. The procedure was suitably specific in discriminating between SLE and related flaviviruses, detecting only high infectious doses of heterologous antigens.