bluuebunny/crossref_metadata_2025 huggingface dataset:
Variable quantitation of Haemophilus influenzae type b anticapsular antibody by radioantigen binding assay
Authors: Ward J I , Greenberg D P , Anderson P W , Burkart K S , Christenson P D , Gordon L K , Kayhty H , Kuo J S , Vella P
Published: January 2020

The measurement of antibody to Haemophilus influenzae type b capsular polysaccharide is important in the study of natural immunity and in the immunogenicity evaluation of H. influenzae type b vaccines. Several radioantigen binding assays (RABA) have been developed to measure H. influenzae type b anticapsular antibody, but recent immunogenicity data obtained with structurally similar vaccines suggest major differences in antibody quantitation in different laboratories. To evaluate interlaboratory variability in the measurement of anticapsular antibody levels, we blindly evaluated a sample of 40 pre- and postimmunization sera by eight RABAs in different laboratories. Evaluation of RABA methods revealed differences in polysaccharide antigens, radiolabeling methods, concentration and volume of antigen and antibody, and other assay methods. The reported results of assays varied significantly between laboratories (up to sixfold differences in geometric means), in part because of differences in assay sensitivity and different proportions of samples having undetectable levels of antibody (0 to 65% of specimens with undetectable levels). After standardizing the limit of sensitivity for all assays (0.125 microgram/ml), the results of all combinations of paired analyses of RABA assays correlated well (r = 0.88 to 0.99) but the geometric mean levels still varied as much as twofold. For individual sera, the differences between paired assays often were substantial (P less than or equal to 0.0001, paired t test), with some results varying as much as 64-fold. Differences were greatest for lower levels of antibody. There was good comparability and interlaboratory reproducibility of some assays but not of others. Intrinsic or extrinsic labeling of the antigen was not a major determinant of comparability. In most instances, the current variation in the quantitation of antibody levels by these assays precludes interassay comparisons. A standardized measurement of antibody needs to be developed to adequately compare results between different H. influenzae type b immunogenicity studies.
Detection of antibody to pseudorabies virus in swine sera by indirect immunoperoxidase plaque staining
Authors: Sato K , Tanaka Y , Kurogi H , Tokuhisa S , Numba K , Inaba Y , Matumoto M
Published: January 2020

A new method for the detection of pseudorabies antibody in swine sera was developed by use of the indirect immunoperoxidase plaque staining test. The indirect immunoperoxidase plaque staining test demonstrated serologic responses in pigs that were subcutaneously infected with pseudorabies virus. The test had a sensitivity and a specificity comparable to those of the complement-dependent neutralization test and appeared to be somewhat more sensitive than the neutralization test and the enzyme-linked immunosorbent assay. The test was simple to perform, and the results could be read with the unaided eye under ordinary light, making the test particularly suitable for the routine testing of large numbers of serum samples.
Possible role of capillary action in pathogenesis of experimental catheter-associated dermal tunnel infections
Authors: Cooper G L , Schiller A L , Hopkins C C
Published: January 2020

An animal model of vascular-catheter-associated dermal tunnel infections was developed to study the pathogenesis of such infections. Bacteria inoculated onto entry sites of catheters into skin could be identified by culture and Gram stain on the tips of plastic catheters (4 cm from the entry site) within 1 h of inoculation, whether the animal was inoculated at the time of insertion of the catheter or 1 week afterwards. Histological examination of dermal tunnels revealed that the introduction of bacteria preceded the development of tissue inflammation. Bacteria on entry sites of percutaneous catheters moved rapidly from the entry site into the dermal tunnel along the external catheter surface, perhaps suspended in a fluid phase and propelled by capillary action.
Alkaline phosphatase-conjugated oligonucleotide probes for enterotoxigenic Escherichia coli in travelers to South America and West Africa
Authors: Oprandy J J , Thornton S A , Gardiner C H , Burr D , Batchelor R , Bourgeois A L
Published: January 2020

Several studies have demonstrated the usefulness of 32P-labeled recombinant DNA probes for identifying enterotoxigenic Escherichia coli (ETEC). The use of radioisotopes and X-ray development, however, severely handicaps the utility of DNA probes in most clinical laboratories. In this study, enzyme-labeled oligonucleotide probes for ETEC LT (heat-labile toxin) and ST (heat-stable toxin) genes were compared with the standard Y1 adrenal cell and suckling mouse assays for their ability to identify ETEC in a population of American adults experiencing acute episodes of diarrhea in South America and West Africa. The LT probe hybridized with 12% (64 of 529) of the E. coli colonies tested, whereas 11% (57 of 529) were positive by Y1 adrenal cell assay. DNA from 9% (47 of 529) of the E. coli colonies tested hybridized with the ST probe, whereas only 5% (28 of 529) produced ST as measured by the suckling mouse bioassay. For the patient samples tested, correlation between probe and bioassay for LT was 97%, or three discrepancies in 111 patients tested. Overall concordance of the ST probe and bioassay was 95%, or five discrepancies in 111 patients. Enzyme-labeled oligonucleotide probes represent a major advance in the diagnosis of ETEC-associated diarrheal disease and may be used in laboratories with minimal equipment.
Serum antibodies to pneumolysin in patients with pneumonia
Authors: Kanclerski K , Blomquist S , Granström M , Möllby R
Published: January 2020

Serum antibodies to purified pneumolysin were determined by enzyme-linked immunosorbent assay (ELISA) in paired samples from 406 adult patients with community-acquired pneumonia and in samples from 184 healthy controls. A high sensitivity (83%) was obtained in patients with blood culture-confirmed pneumococcal pneumonia. In patients with a tentative pneumococcal diagnosis based on culture of samples from the sputum or the nasopharynx, 45% were positive by ELISA. The difference likely reflected the different relevance of cultural findings for the diagnosis of pneumococcal pneumonia. A significant rise in ELISA titer was found in 17% of the patients. When the diagnosis was also based on high titers, 25% were positive. Pneumococcal pneumonia diagnosed by the pneumolysin ELISA was significantly more common in the patients with a more severe disease and who required hospitalization (21 versus 5% for outpatients). Younger patients were more often positive for pneumococci as determined by high titers, while older patients showed titer rises. Mixed infections with other infectious agents were not uncommon. The finding of low titers in acute-phase samples from positive patients and in the youngest and oldest age groups of healthy controls were unexpected, indicating that further studies on the role of pneumolysin in pneumococcal disease are warranted.
Macroscopic purulence, leukocyte counts, and bacterial morphotypes in relation to culture findings for sinus secretions in acute maxillary sinusitis
Authors: Jousimies-Somer H R , Savolainen S , Ylikoski J S
Published: January 2020

Macroscopic purulence, leukocyte counts, and bacterial morphotypes in Gram-stained smears were investigated in 335 sinus secretions (240 aspirates and 95 injection aspirates) obtained by puncture in 234 young patients with acute maxillary sinusitis. Over 90% of the 147 aspirates macroscopically classified as purulent also contained high numbers of leukocytes (greater than 20 per oil immersion field). A total of 82% of the 147 macroscopically purulent aspirates and 79% of the 156 aspirates containing high numbers of leukocytes yielded presumed sinus pathogens by culture in quantities of greater than 10(3) CFU/ml. Streptococcus pneumoniae or Streptococcus pyogenes was associated relatively more often (92 or 87%, respectively) with high numbers of leukocytes than Haemophilus influenzae, which was not infrequently (29%) recovered from the less purulent aspirates. When a bacterial morphotype was seen in the Gram-stained smear, a corresponding sinus pathogen was isolated in quantities of greater than 10(3) CFU/ml in 92% of aspirates. Other bacterial species (most often staphylococci) were usually isolated in low numbers and were almost never seen in the smear, suggesting nasal contamination. The 95 injection aspirates behaved, to a large extent, like diluted aspirates, with the exception that there was a higher frequency of probable nasal contamination. Macroscopic purulence, high leukocyte counts, and bacterial morphotypes seen in Gram-stained smears each predicted well the isolation of a presumed sinus pathogen and in some cases supported the significance of an otherwise doubtful culture finding. However, the macroscopic appearance of the secretion should not be used to screen samples for culture, because in several cases H. influenzae grew from nonpurulent samples as well.
Characteristics of coagulase-negative staphylococci that help differentiate these species and other members of the family Micrococcaceae
Authors: Hébert G A , Crowder C G , Hancock G A , Jarvis W R , Thornsberry C
Published: January 2020

One hundred reference strains and 1,240 clinical isolates representing 26 species of the family Micrococcaceae were used to evaluate the potential of tests for synergistic hemolysis, adherence to glass, pyroglutamyl-beta-naphthylamide hydrolysis, and susceptibility to a set of five antimicrobial agents for differentiating these species and strains within the species. Sixty-eight percent of the clinical isolates exhibited synergistic hemolysis; 69% of the clinical staphylococci but none of the micrococci or stomatococci were adherence positive, and 92% of the strong positive adherence reactions were produced by strains of Staphylococcus epidermidis. Strains from 15 of the species were pyroglutamyl-beta-naphthylamide positive, but this test separated Staphylococcus xylosus from other novobiocin-resistant staphylococci and Staphylococcus intermedius from other coagulase-positive species. A polymyxin B disk helped differentiate S. epidermidis from most other coagulase-negative staphylococci, and a bacitracin disk (10 U) helped differentiate Staphylococcus haemolyticus from most other novobiocin-susceptible staphylococci. All strains that were susceptible to furazolidone and resistant to Taxo A disks (bacitracin, 0.04 U; BBL Microbiology Systems, Cockeysville, Md.) were staphylococci. We observed a 91% correlation between species identification obtained with the Staph-Ident system (Analytab Products, Plainview, N.Y.) and conventional methods; but the micrococci and stomatococci were incorrectly identified as staphylococci with Staph-Ident, and several isolates of S. epidermidis were misidentified as Staphylococcus hominis because they were alkaline phosphatase negative. Both these problems can be prevented by adding the simple tests we describe to those already recommended when the Staph-Ident system is used to identify isolates of gram-positive, catalase-positive cocci.
Monoclonal antibodies against different epitopes on colonization factor antigen I of enterotoxin-producing Escherichia coli
Authors: Lopez-Vidal Y , Klemm P , Svennerholm A M
Published: January 2020

Hybridoma-secreting monoclonal antibodies (MAbs) against colonization factor antigen I (CFA/I) were produced by the fusion of spleen cells from immunized BALB/c mice with F/O myeloma cells. The 25 MAbs with the highest antibody titer against CFA/I, as determined by an enzyme-linked immunosorbent assay, were studied for specificity and the capacity to agglutinate CFA/I-carrying bacteria. Most of the MAbs agglutinated a majority of 16 CFA/I-positive strains tested but not any of a number of CFA-deficient mutants or strains carrying other colonization factors (CFA/II and CFA/IV). One MAb that agglutinated all the CFA/I-positive strains and one MAb that did not agglutinate any of these strains were compared for their reactivities with different preparations of CFA/I. Whereas both MAbs bound to or could be inhibited by isolated CFA/I fimbriae as well as the subunit protein, only the agglutinating MAb bound to CFA/I, as expressed on whole bacteria. The nonagglutinating MAb, on the other hand, bound considerably better than the agglutinating MAb to a peptide corresponding to the 46 N-terminal amino acid residues of the CFA/I subunit protein. These results suggest that the two MAbs are directed against different epitopes on CFA/I.
Genome fingerprinting of Pseudomonas aeruginosa indicates colonization of cystic fibrosis siblings with closely related strains
Authors: Grothues D , Koopmann U , von der Hardt H , Tümmler B
Published: January 2020

The epidemiology of Pseudomonas aeruginosa infection at a cystic fibrosis (CF) center was monitored over a 3-year period. A total of 835 isolates from 72 unrelated patients and 22 siblings with CF were analyzed by genome fingerprinting and serotyping, bacteriophage typing, and pyocin typing. For genome fingerprinting, bacterial chromosomes were digested with one of the restriction endonucleases SpeI, DraI, XbaI, SspI, and NheI, which cut only rarely, and subsequently separated by field inversion gel electrophoresis. The physical genome analysis allowed us to classify P. aeruginosa strains in terms of DNA relatedness. Related strains differed by fewer than six DraI bands in the fingerprint, whereas unrelated strains differed by more than 20 DraI bands. All unrelated CF patients were colonized with different strains. The absence of a nosocomial spread of organisms at the CF center was attributed to the strict hygiene measures observed at the hospital. CF siblings were harboring either identical or closely related strains; transmission within the family is thought to be the most likely cause.
Meningococcal phenotypic and genotypic characteristics and human antibody levels
Authors: Kristiansen B E , Lind K W , Mevold K , Sørensen B , Frøholm L O , Bryn K , Tjade T , Bøvre K
Published: January 2020

During a 2-month period in 1984, throat and blood samples were collected from 1,102 healthy persons of different ages living in the city of Tromsø, Norway. One hundred and eight persons (9.8%) were meningococcal carriers, but the carrier rate varied with sex and age. Twenty-nine isolates (26.9%) were of serogroup B, and 31 (28.7%) isolates contained the serotype 15 antigen. Sixty-eight (63.0%) isolates were nontypable, 49 (45.4%) were nongroupable, and 21 (19.4%) were sulfonamide resistant. All nine serotype 2a isolates and eight (25.8%) of the serotype 15 isolates were sulfonamide resistant. Only these eight serotype 15, sulfonamide-resistant isolates had a DNA fingerprint similar to that of the majority of systemic isolates of Neisseria meningitidis in Norway. The average level of antimeningococcal immunoglobulin G antibodies, as determined by a whole-bacterium enzyme immunoassay with a systemic B:15 meningococcal strain as the antigen, was low until 12 to 15 years of age and then steadily increased.
Characterization of Vibrio metschnikovii and Vibrio gazogenes by DNA-DNA hybridization and phenotype
Authors: Farmer J J , Hickman-Brenner F W , Fanning G R , Gordon C M , Brenner D J
Published: January 2020

Vibrio metschnikovii and Vibrio gazogenes are two new Vibrio species that have been little studied. Thirteen strains of V. metschnikovii were highly related to the type strain, NCTC 8443, by DNA-DNA hybridization. Relatedness values were 83 to 90% at 60 degrees C and 75 to 84% at the more stringent 75 degrees C. Divergence values ranged from 0.7 to 1.9. Strains of V. metschnikovii were oxidase negative and did not reduce nitrate to nitrite. The other phenotypic characteristics agreed with published data. Twenty-three strains of V. gazogenes were isolated from salt marshes and marshy areas on the coast of North and South Carolina. A new medium, marine agar supplemented with an additional 2.5% agar, reduced the problem of swarming by marine Vibrio species and enhanced the isolation of V. gazogenes and other organisms. By DNA-DNA hybridization, 22 of 23 strains were 76% or more related to the type strain of V. gazogenes, ATCC 29988. However, four DNA hybridization subgroups were defined on the basis of divergence values and/or phenotype. Strains of DNA group 1 were more highly related to each other, and this group contained the type strain and six other strains. Strains of DNA group 2 were more highly related to each other, and this group contained reference strain ATCC 43942 and 14 other strains. Strains of DNA group 1 did not ferment melibiose or D-sorbitol (one strain was sorbitol positive), but strains of DNA group 2 fermented both sugars. A revised phenotypic description of V. gazogenes based on 24 strains was written on the basis of reactions (within 2 days of incubation) at 25 degrees C in media supplemented with Na+, K+, and Mg2+. Positive results (100% positive unless indicated) included motility; gas production during fermentation (96% at 2 days, 100% at 3 to 7 days); growth in nutrient broth with the addition of 1% NaCl (88%), 2% NaCl, 3.5% NaCl, 6% NaCl, 8% NaCl, and 10% NaCl (92%); dry red or orange colonies on marine agar; and fermentation of L-arabinose, cellobiose, D-galactose (88%), D-glucose, lactose (88%), maltose, D-mannitol (96%), D-mannose, salicin, sucrose, trehalose, and D-xylose. Negative results included oxidase; nitrate reduction to nitrite (4% positive); indole production; lysine decarboxylase; ornithine decarboxylase; arginine dihydrolase; swarming; growth on TCBS agar; growth in nutrient broth with 0% NaCl, 0.1% NaCl, 0.2% NaCl, 0.3% NaCl, and 0.4% NaCl (8% positive); and fermentation of adonitol, D-arabitol, dulcitol, erythritol, D-galacturonate, i-inositol, alpha-methyl-D-glucoside, raffinose, and L-rhamnose. Variable results were found for the Voges-Proskauer reaction (62% positive), growth in nutrient broth plus 0.5% NaCl (29%) and 12% NaCL (42%), and fermentation of melibiose (71%) and D-sorbitol (71%).
Characterization of Escherichia coli serotype O157:H7
Authors: Ratnam S , March S B , Ahmed R , Bezanson G S , Kasatiya S
Published: January 2020

A total of 174 strains of Escherichia coli serotype O157:H7 representing human isolates obtained from outbreaks and sporadic cases of hemorrhagic colitis, hemolytic-uremic syndrome, and nonbloody diarrheal illnesses as well as from asymptomatic carriers across Canada and the United States were examined. E. coli serotype O157:H7 possessed distinct biochemical markers, a 100% negative reaction for beta-glucuronidase and sorbitol, and a 100% positive reaction for raffinose and dulcitol; all strains otherwise were biochemically typical of E. coli. The vast majority (97%) of the strains were susceptible to commonly used antimicrobial agents. All strains produced readily detectable levels of Verotoxin; however, with polymyxin extraction, nearly 50% of the strains showed up to a 10-fold increase in the toxin level. None were found to mediate hemagglutination of human group A erythrocytes with or without D-mannose. The majority (approximately 70%) of the strains showed localized and diffuse adherence to HEp-2 cells and Henle 407 cells, and the adherence patterns were not very different from those observed among other E. coli strains. Twenty phage types were recognized, with phage types 1 and 2 accounting for 65% of the test strains. Plasmid analysis indicated three basic plasmid profiles: profile I was characterized by 68.7- and 4.2-megadalton (MDa) plasmids (62% of strains), profile II was characterized by 66.2- and 1.8-MDa plasmids (20% of strains), and profile III was characterized by a 62.5-MDa plasmid (18% of strains). A small number (19%) of the strains carried at least one additional plasmid over the basic complements, and these could be considered to constitute a miscellaneous category. None of the above-described characteristics of E. coli serotype O157:H7 could be directly correlated with one another, with the nature of infection, or with the geographical distribution of strains.
Immunologic diversity among serogroup 1 Legionella pneumophila urinary antigens demonstrated by monoclonal antibody enzyme-linked immunosorbent assays
Authors: Kohler R B , Wilde C , Johnson W , Joly J , Wheat L J , Baker R , Misfeldt M
Published: January 2020

We tested urine specimens from 222 patients with serogroup 1 Legionella pneumophila pneumonia in two enzyme-linked immunosorbent assays (ELISAs) which used different monoclonal antibodies (A and B) as detector antibodies. Of 171 specimens which contained enough antigen to be detected in the ELISAs, 169 reacted in only one of the two assays. A total of 25 patients whose infections were acquired in any of three Indianapolis hospitals excreted antigen reactive with monoclonal antibody B, but 18 patients who were treated for infections acquired elsewhere reacted with monoclonal antibody A. The urinary antigen ELISA reactivity patterns correlated with the reactivity patterns of L. pneumophila isolates when a separate panel of seven monoclonal antibodies was used. The isolate patterns, in turn, correlated well with environmental isolate patterns from two of the hospitals with nosocomial cases. We conclude that at least two different epitopes exist on the antigen molecules in urine from patients with serogroup 1 L. pneumophila pneumonia and that the subtyping of urinary antigens can be useful epidemiologically.
Plasmid analysis of Shigella dysenteriae type 1 isolates obtained from widely scattered geographical locations
Authors: Haider K , Kay B A , Talukder K A , Huq M I
Published: January 2020

Plasmid profiles and antimicrobial susceptibility patterns of 343 strains of Shigella dysenteriae type 1, obtained from 18 different geographical locations, were analyzed. Three plasmids, with molecular sizes of 140, 6, and 2 megadaltons (MDa), were present in 94, 98, and 96%, respectively, of the 343 strains isolated during either epidemic or nonepidemic periods from 1965 to 1987. In addition to these plasmids, 83% of the strains harbored a 4-MDa plasmid and 25% harbored a 20-MDa plasmid. Various plasmid profiles were observed in which the 140-, 6-, and 2-MDa plasmids occurred commonly, irrespective of the place of isolation and drug resistance pattern of the strains. Certain profiles showed significant association with drug resistance patterns. These findings suggest that three plasmids, of molecular sizes 140, 6, and 2 MDa, are unique to S. dysenteriae type 1 strains and may indicate the global spread of a pathogenic bacterial clone. Additionally, these core plasmids, plus plasmids of various other sizes, could be used to identify emerging subclones which are causing both epidemic and sporadic disease. Thus, plasmid profiles of S. dysenteriae type 1 strains can be used to monitor possible pandemic strains as well as individual epidemic strains.
Latex agglutination and enzyme-linked immunosorbent assays for cytomegalovirus serologic screening of transplant donors and recipients
Authors: Chou S W , Scott K M
Published: January 2020

The effectiveness of three serologic assays (two enzyme-linked immunosorbent assays [ELISAs] and latex agglutination) for cytomegalovirus (CMV) serologic matching of donors and recipients was assessed over a 2-year period in a major organ transplant program. Sera with equivocal test results were investigated by repeat testing of serum samples and additional specimens from the individuals involved and monitoring of CMV infection in recipients. An in-house ELISA identified all CMV-infective donors as seropositive. Of 63 ELISA-positive donors, 5 were negative by latex agglutination; recipients from 3 of these donors developed primary CMV infection posttransplant. The in-house ELISA and a commercial ELISA (Abbott enzyme immunoassay; Abbott Laboratories, North Chicago, Ill.) had a 93% concordance of results; follow-up testing indicated that the Abbott assay was sensitive but had a false-positive rate of about 11%. One recipient with a false-positive result developed symptomatic primary CMV infection after receiving a seropositive organ. Thus, performance characteristics of currently used screening assays affect recipient outcome.
DNA probe technology for rapid detection of Haemophilus influenzae in clinical specimens
Authors: Malouin F , Bryan L E , Shewciw P , Douglas J , Li D , Van den Elzen H , Lapointe J R
Published: January 2020

In a previous study, we reported that a 5-kilobase Haemophilus influenzae DNA fragment involved in penicillin-binding protein expression could be used as a probe for specific detection of H. influenzae strains (F. Malouin and L. E. Bryan, Mol. Cell. Probes 1:221-232, 1987). Here, we report the ability of this probe to detect H. influenzae in clinical specimens. In a bacterial dot experiment, there was strong hybridization of the 32P-labeled probe to nonencapsulated and serotype a through f H. influenzae strains. The detection of H. influenzae in body fluids was then evaluated by using pooled human serum, urine, cerebrospinal fluid, and sputum as dilution media for H. influenzae, Haemophilus aegyptius, Haemophilus parainfluenzae, and Escherichia coli cells. At 65 degrees C, the probe hybridized to H. influenzae and H. aegyptius (greater than or equal to 10(5) cells) in all fluids. There was no hybridization with the E. coli negative control, and H. parainfluenzae hybridized when greater than or equal to 10(7) cells were used. Experiments performed at 73 and 80 degrees C permitted elimination of H. parainfluenzae hybridization. The detection of H. influenzae in 232 sputa from patients with respiratory tract infections was very specific (96 to 97%) and sensitive (74 to 100%) when the total time of the procedure was sufficient (6 to 24 h) and when the experiments were performed at 80 degrees C. In addition, the probe detected three of three and four of four H. influenzae-infected cerebrospinal fluids and blood cultures, respectively, and did not react with pneumococcus- or streptococcus-infected cerebrospinal fluids. Finally, by using a small-scale procedure, the probe rapidly detected H. influenzae in cerebrospinal fluid and sputum specimens (4 and 8 h, respectively). These results imply prompt diagnosis of H. influenzae infections caused by nonencapsulated and serotype a through f strains.
Production of Paracoccidioides brasiliensis exoantigens for immunodiffusion tests
Authors: De Camargo Z , Unterkircher C , Campoy S P , Travassos L R
Published: January 2020

Growth curves of the yeast form of Paracoccidioides brasiliensis B-339 based on total and viable cell counts were determined. Crude culture filtrate antigens were obtained after 7, 10, 15, 20, 25, and 30 days of incubation. Different patterns of proteins were obtained by affinity chromatography on Sepharose 4B-immunoglobulin G complex made with immunoglobulin G from patients with paracoccidioidomycosis, with subsequent analyses by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and scanning densitometry. Three major proteins were excreted during the time course of a 30-day culture: a doublet at 20 to 21 kilodaltons (kDa) and molecules of 43 and 52 kDa. The 43-kDa antigen was present throughout the growth period, and its level reached a peak on days 15 to 20 and then decreased considerably toward day 30. The antigenic preparations collected on days 7, 10, 15, and 20 gave better reactions in immunodiffusion tests than those collected on days 25 and 30. The 7-day exoantigen gave a sensitivity of 97.1% and specificity of 100% on immunodiffusion. The main line of precipitation had a very high intensity, showing a total identity with that of a previously purified glycoprotein of 43 kDa. A 7-day crude exoantigen displayed a high level of sensitivity and specificity, being reproducible from batch to batch and retaining its activity for years when kept lyophilized. A protocol is recommended for the production of a stable diagnostic antigen to be used in immunodiffusion tests for paracoccidioidomycosis.
Enzymatic degradation of urinary indoxyl sulfate by Providencia stuartii and Klebsiella pneumoniae causes the purple urine bag syndrome
Authors: Dealler S F , Hawkey P M , Millar M R
Published: January 2020

The etiology of the purple urine bag syndrome (PUBS), in which the urinary catheter bag of some elderly patients develops intense purple coloration, was studied. The purple was found to be a mixture of indirubin dissolved in the plastic and indigo on its surface. Six patients with PUBS were studied, and Providencia stuartii was isolated from the urine of five and Klebsiella pneumoniae was isolated from the urine of one. These strains produced indigo in 7.9 mM indoxyl sulfate-containing agar. One hundred and fifty isolates of 41 species of bacteria were tested for their ability to produce indigo on agar containing indoxyl sulfate, but only 17 of 27 strains of P. stuartii, a single strain of Klebsiella pneumoniae, and Enterobacter agglomerans were positive. All of the indigo-producing bacteria had an indoxyl phosphatase with a pI of 6.4. This enzyme also possessed indoxyl sulfatase activity and was not present in strains that were unable to produce indigo from indoxyl sulfate. We conclude that PUBS results from the decomposition of urinary indoxyl sulfate to indigo and indirubin by bacteria (notably P. stuartii). As elderly catheterized patients often have high urinary indoxyl sulfate levels and colonization of their urinary tract with P. stuartii, the condition is most commonly seen in them.
Detection of genomic variation in Providencia stuartii clinical isolates by analysis of DNA restriction fragment length polymorphisms containing rRNA cistrons
Authors: Owen R J , Beck A , Dayal P A , Dawson C
Published: January 2020

Chromosomal DNA from 26 strains of Providencia stuartii isolated mainly in hospitals in the United Kingdom and reference strains of P. stuartii, P. rustigianii, and Proteus vulgaris were digested with the restriction endonucleases EcoRI and HindIII. After electrophoresis in agarose gels, the fragments were subjected to Southern blot hybridization analysis with a biotin-labeled cDNA probe transcribed from a mixture of 16S and 23S rRNA from P. stuartii NCTC 11800T. The pattern of bands (the rDNA fingerprint), which depended on restriction fragment length polymorphisms containing rRNA genes, was used as a measure of minor genomic variation within and between species. The P. stuartii clinical isolates had similar total digest patterns, but the rDNA fingerprints revealed some heterogeneity between strains, with EcoRI digests providing better strain discrimination than HindIII. Such rDNA fingerprints comprised between five and seven bands with sizes in the range of 5 to 28 kilobases. The 11 different EcoRI patterns were compared by numerical analysis, and several groups or subgroups of strains were identified. Over half (15 of 26) of the urease-negative isolates (subgroups Aa and Ab) had patterns that differed only by the presence or absence of a 25-kilobase band. Urease-negative strains from other clinical material were more heterogeneous in their patterns. No correlation was apparent between strain pattern group and urease production or geographic location of isolate. The P. stuartii rDNA fingerprints were quite distinct from those of allied Providencia and Proteus species and provided a more sensitive measure of minor genomic differences than total DNA digests did.
Evaluation of various antibiotics for induction of L forms from Staphylococcus aureus strains isolated from bovine mastitis
Authors: Owens W E
Published: January 2020

Forty-five strains of Staphylococcus aureus were treated with 11 antibiotics and tested for induction to L forms. Thirty-seven strains were induced to L forms with at least one antibiotic, while eight strains produced no L forms under the conditions used. L forms were induced only with beta-lactam antibiotics and with a combination of penicillin and streptomycin. Novobiocin induced no true L forms but induced intermediate forms from seven strains. Strains resistant to penicillin yielded L forms only with beta-lactam antibiotics active against penicillin-resistant organisms. Strains failing to yield L forms were susceptible to the antibiotics used, and resistance appeared to play no role in the induction of L forms with these strains.
Serological responses of patients with lepromatous and tuberculoid leprosy to 30-, 31-, and 32-kilodalton antigens of Mycobacterium tuberculosis
Authors: Rumschlag H S , Shinnick T M , Cohen M L
Published: January 2020

Sera from patients with lepromatous and tuberculoid leprosy were examined in immunoblot assays for antibodies to Mycobacterium tuberculosis culture filtrate antigens. Antibodies to 30- and 31-kilodalton proteins were present in 88 and 81%, respectively, of 16 patients with lepromatous disease and absent in 16 patients with tuberculoid disease. Antibodies to a 32-kilodalton protein were found in 12 and 38% of lepromatous and tuberculoid patients, respectively. These reactivities may be useful for distinguishing lepromatous and tuberculoid leprosy.
Dysgonic fermenter 3 bacteremia in a neutropenic patient with acute lymphocytic leukemia
Authors: Aronson N E , Zbick C J
Published: January 2020

Persistent dysgonic fermenter 3 bacteremia occurred in a granulocytopenic leukemic patient on broad-spectrum antibiotic therapy. This is the first reported case of bacteremia with this fastidious gram-negative rod. Characteristic microbiology and antibiotic susceptibility testing are reviewed. Trimethoprim-sulfamethoxazole therapy eliminated the bacteremia.
Inhibition of Escherichia coli serotype O157:H7 by bromthymol blue
Authors: Gubash S M , Anand C M , Stokman M
Published: January 2020

Bromthymol blue, at a concentration of 0.1% in tryptose-glucose broth, inhibited growth of 98.4% of Escherichia coli serotype O157:H7 isolates but only 0.8% of E. coli non-O157:H7 isolates after an overnight incubation at 44.5 degrees C, but not 35 degrees C. The inhibition was dependent on temperature, density of inoculum, bromthymol blue concentration, time of incubation, and composition of the medium. Compared with serologic typing, the inhibition had sensitivity, specificity, predictive values of the positive and negative tests, and overall agreement between the two tests of 98.4, 99.2, 98.4, 99.2, and 98.9%, respectively. The inhibition could be useful as a presumptive test to identify E. coli isolates of serotype O157:H7, especially in laboratories that do not have serotyping capabilities.
Enzyme-linked immunosorbent assay to evaluate the immunogenicity of a polyvalent Klebsiella capsular polysaccharide vaccine in humans
Authors: Granström M , Wretlind B , Markman B , Cryz S
Published: January 2020

A highly sensitive enzyme-linked immunosorbent assay was developed for Klebsiella capsular polysaccharide (CPS) and used to evaluate the immunoglobulin G (IgG) antibody response to a 24-valent CPS vaccine in seven adult volunteers. The median rise in titer to all vaccine antigens in samples from the volunteers was significant (twofold or greater). Significant IgG responses to 11 immunologically related serotypes not included in the vaccine were also noted. The mean cross-reacting IgG titer of 127.2 was only slightly lower than the mean titer of 175.7 to the serotypes in the vaccine (P less than 0.05). The mean 29.9-fold increase in titer to the serotypes in the vaccine was significantly higher than the mean 13.5-fold increase in titer to the additional antigens (P less than 0.001). The difference was partly because of the significantly lower (P less than 0.01) natural antibody titers in the preimmune sera to the serotypes in the vaccine, compared with those to serotypes not included in the vaccine. The selection of vaccine serotypes was based on the frequency of serotype isolation from cases of Klebsiella bacteremia. The above findings, which show low levels of natural antibody to these serotypes, support the hypothesis that anti-CPS antibody is protective against bacteremic disease.
Antibodies to mycobacterial peptidoglycolipid and to crude protein antigens in sera from different categories of human subjects
Authors: Wayne L G , Anderson B , Chetty K , Light R W
Published: January 2020

Sera from patients with disease caused by the Mycobacterium avium complex (M. avium and M. intracellulare), M. kansasii, or M. tuberculosis and from subjects who did not have a mycobacterial disease were tested by enzyme-linked immunosorbent assay against peptidoglycolipid antigens representing each of the 15 most common serovars of the M. avium complex and against crude protein antigen extracts of M. avium and M. tuberculosis. The highly specific peptidoglycolipid antigens yielded positive reactions in 83% of M. avium complex patients, 57% of active-tuberculosis patients, and 14% of subjects without mycobacterial disease. Reactions to more than 1 of the 15 peptidoglycolipid antigens were found only in patients with infections caused by mycobacteria, suggesting that a mycobacterial pulmonary lesion is readily colonized by mycobacteria other than the one that initiated the lesion. The two crude mycobacterial protein antigens were highly cross-reactive, with little if any capacity to discriminate between infections caused by any of the mycobacteria studied. Moreover, they did not appear to be more sensitive than the peptidoglycolipids. The data suggest that it is unlikely that a practical and reliable serological test can be developed that will distinguish between transient subclinical infection and significant disease caused by common environmental mycobacteria, such as members of the M. avium complex. Success in developing such a test for nonenvironmental mycobacteria, such as M. tuberculosis, appears more likely.
Biotinylated DNA probes for exotoxin A and pilin genes in the differentiation of Pseudomonas aeruginosa strains
Authors: Samadpour M , Moseley S L , Lory S
Published: January 2020

Biotin-labeled DNA probes derived from Pseudomonas aeruginosa exotoxin A and pilin genes were tested for their ability to distinguish strains among a selected group of P. aeruginosa isolates. Probing of Southern blots of restriction digests of DNA from test strains with the exotoxin A probe demonstrated a unique hybridization pattern for each independently isolated strain containing the exotoxin A gene. Two phenotypically distinct strains isolated from the same patient were found to be identical in their DNA hybridization patterns. By using a pilin gene probe, similar distinction was made between independent strains, while strains from the same source were confirmed to be identical. Furthermore, DNA from a strain of P. aeruginosa lacking the exotoxin A gene yielded a unique pattern of restriction fragments which hybridized to the pilin gene probe. The exotoxin A and the pilin probes may together prove to be useful tools in epidemiological surveys during outbreaks of P. aeruginosa infection.
Classification of Leptospira interrogans serovar lai strain 017 by using monoclonal antibodies
Authors: Masuzawa T , Kumagai M , Shimizu T , Yanagihara Y
Published: January 2020

Leptospira interrogans serovar lai was identified in China in 1966 as a new serovar of the icterohaemorrhagiae serogroup by cross-absorption tests. In this study, we established three hybridoma cell lines producing monoclonal antibodies (MAbs) of the immunoglobulin G3 subclass (LW1, LW2, and LW3) and of the immunoglobulin M class (LW4a) against serovar lai strain 017 by the cell fusion technique. Immunological reactivities of the MAbs were determined by the microscopic agglutination test, enzyme-linked immunosorbent assay (ELISA), and indirect immunofluorescence assay. MAbs LW1 and LW3 agglutinated cells of serovars lai, birkini, and gem of serogroup icterohaemorrhagiae. LW2 agglutinated various serovars of serogroup icterohaemorrhagiae, except for serovar tonkini. LW4a reacted positively with various Leptospira species, including a new species, Leptospira parva, in the ELISA and indirect immunofluorescence assay. However, LW4a did not react with Leptonema illini 3055. The results of an inhibition ELISA with heated outer envelope (OE) or periodate-oxidized OE suggested that these MAbs recognize a carbohydrate moiety of the OE as the antigenic determinant.
Edwardsiella tarda serotyping scheme for international use
Authors: Tamura K , Sakazaki R , McWhorter A C , Kosako Y
Published: January 2020

A combination of two systems for the serotyping of Edwardsiella tarda developed independently at the National Institute of Health, Tokyo, Japan, and the Centers for Disease Control, Atlanta, Ga., has enabled a single serotyping scheme comprising 61 O groups and 45 H antigens to be established for international use.
Annual incidence, epidemiology, and comparative in vitro susceptibilities to cefoxitin, cefotetan, cefmetazole, and ceftizoxime of recent community-acquired isolates of the Bacteroides fragilis group
Authors: Goldstein E J , Citron D M
Published: January 2020

The six species of the Bacteroides fragilis group are potent pathogens and commonly have different susceptibility patterns. We determined the relative annual isolation rate of anaerobic bacteria and the susceptibility of B. fragilis group species isolated during 1987 at two community hospitals. The relative frequencies of isolation of 261 strains were as follows: B. fragilis, 61%; B. thetaiotaomicron, 17%; B. distasonis, 7%; B. vulgatus, 6%; B. ovatus, 5%; and B. uniformis, 4%. A total of 234 recent clinical isolates were tested against cefmetazole, cefotetan, cefoxitin, ceftizoxime, clindamycin, imipenem, and piperacillin by a brucella agar dilution method. Imipenem was the most active agent tested with all but three isolates (two B. vulgatus and one B. distasonis) susceptible to less than 2 micrograms/ml. Of the cephalosporins tested, cefoxitin, cefotetan, and cefmetazole were relatively equal against B. fragilis, with 93 to 98% of strains susceptible to 32 micrograms/ml. Ceftizoxime was less active, with an MIC for 90% of strains tested of 128 micrograms/ml and only 75% of isolates susceptible to 32 micrograms/ml. Against B. ovatus, B. vulgatus, B. thetaiotaomicron, and B. uniformis, cefoxitin showed a two- to threefold-superior activity compared with that of cefotetan and cefmetazole. In general, ceftizoxime was much less active, except against B. distasonis, for which 78% of isolates were susceptible to 32 micrograms/ml compared with 68% for cefoxitin, 19% for cefmetazole, and 16% for cefotetan. Clindamycin and piperacillin showed activity similar to that of cefoxitin, except piperacillin was less active versus B. vulgatus and B. distasonis. We therefore suggest that clinical laboratories determine the species of B. fragilis group isolates as well as perform susceptibility studies on the isolates. Clinicians should be aware that while B. fragilis is the most frequent isolate, 38% of isolates are from other, more resistant B. fragilis group species.
Optimal conditions for recovery of the human immunodeficiency virus from peripheral blood mononuclear cells
Authors: Castro B A , Weiss C D , Wiviott L D , Levy J A
Published: January 2020

Optimal conditions for demonstrating the presence of infectious human immunodeficiency virus in peripheral blood mononuclear cells (PMCs) from seropositive individuals involved cocultivation of infected cells with phytohemagglutinin-stimulated PMCs from seronegative donors in the presence of 2 micrograms of Polybrene per ml. The size of the culture vessel also influenced the results; smaller numbers of infected cells were detected under conditions of increased cell density. In addition, an increased normal donor/patient PMC ratio was helpful. The cocultivation approach permitted identification of human immunodeficiency virus in over 90% of seropositive individuals with different clinical conditions. Moreover, reconstruction experiments indicated that this method allows detection of one productively infected CD4+ cell in a population of over 10(6) PMCs.
Characterization of staphylococci from patients with toxic shock syndrome
Authors: Aliu B , Bergdoll M S
Published: January 2020

Fifty staphylococcal strains that produced toxic shock syndrome (TSS) toxin 1 and that were isolated from patients with TSS were characterized. One strain had more properties that were characteristic of Staphylococcus hyicus than of Staphylococcus aureus. Forty-four strains had the same properties or differed in only one property. Thirty-five of the 50 strains produced either enterotoxin A or C or both in addition to TSS toxin 1.
Evaluation of rapid, commercial latex techniques for serogrouping beta-hemolytic streptococci
Authors: Daly J A , Seskin K C
Published: January 2020

The clinical need to rapidly and correctly differentiate beta-hemolytic streptococci into Lancefield groups has prompted the development of commercially available rapid agglutination techniques. A modified Streptex (Wellcome Diagnostics, Research Triangle Park, N.C.) technique and the PathoDx latex Strep Grouping Kit (Diagnostic Products Corporation, Los Angeles, Calif.) technique were applied to 220 strains of beta-hemolytic streptococci that were serologically grouped by standard techniques. Agreements between standard and modified Streptex and PathoDx techniques were 99.1 and 100%, respectively. Modified Streptex produced a false-negative for one group G isolate and a weak-positive reaction for a group G reagent with a nongroupable isolate. Sixty-five strains representative of bacteria that may be found in the posterior pharynx in concentrations high enough to cause potential reactions with antigen detection reagents were tested with Streptex and PathoDx reagents. No cross-reactions were observed with any reagent tested when challenged with these 65 strains. When combined with colonial morphology and hemolytic reaction, both modified Streptex and PathoDx were rapid, specific tests for identifying streptococci, with PathoDx being slightly faster.
Clinical aspects and usefulness of indirect absorbed immunofluorescence for diagnosis of yaws in Central Africa
Authors: Martin P M , Gonzalez J P , Martin M H , Georges-Courbot M C , Palisson M J , Georges A J
Published: January 2020

The incidence of yaws in 533 pygmies from the Central African Republic was surveyed. It appeared that there is still an impressive incidence of yaws in pygmy children who have poor hygiene. Laboratory investigations showed that the Treponema pallidum hemagglutination assay is often negative during the first stage of the disease, while the fluorescent treponemal antibody absorption test is positive and, thus, more sensitive.
Evidence for a feline reservoir for dysgonic fermenter 2 keratitis
Authors: Paton B G , Ormerod L D , Peppe J , Kenyon K R
Published: January 2020

A 78-year-old female developed microbial keratitis from which corneal scrapings grew dysgonic fermenter 2. The infection initially responded poorly to a combination of topical antibiotics and corticosteroids but healed with intensive antibiotic therapy. There was no systemic predisposition to infection, and only feline exposure had occurred. Close association with a cat probably contaminated the eye.
Peritonitis caused by Pseudomonas mesophilica in a patient undergoing continuous ambulatory peritoneal dialysis
Authors: Rutherford P C , Narkowicz J E , Wood C J , Peel M M
Published: January 2020

We describe a case of recurrent peritonitis caused by Pseudomonas mesophilica in a diabetic man receiving continuous ambulatory peritoneal dialysis. Stagnant water on a bath rail used for support by the patient while showering was implicated as the probable source of these infections. We believe this to be the first report of the isolation of this water-associated bacterium in such infections.