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At least 19 recordsLinked to original sources
PubMed1979

Use of quantitative bacteriologic techniques to diagnose catheter-related sepsis.

A case of polymicrobial sepsis occurred in a patient who had a permanent indwelling hyperalimentation catheter. Because it was undesirable to remove the catheter, quantitative bacteriologic techniques were used to determine whether the catheter was the source of sepsis. Blood drawn from a peripheral vein had 25 colonies per milliliter whereas blood drawn through the catheter had more than 10,000 colonies per milliliter. On the basis of these results, the catheter was removed. The catheter tip was found to be infected with the same organisms that were present in the blood. Quantitative bacteriologic techniques may prove useful in diagnosing catheter-related sepsis when it is undesirable to remove the catheter.

Adult↗
PubMed1979

[Quantitative evaluation methods of the chemoantibiotic associations (author's transl)].

In the introductory part a new classification of joint drug actions is submitted, according which three fundamental types are distincted, named respectively interference, cooperation and true interaction. In its turn, interaction is subdivided in three classes (uni-effectual, bis-ineffectual, bis-effectual) in the last of which is placed the most relevant of the interactions, that is synergism, subclassified, at its turn, as additive, super and infra-additive. The second part is devoted to the classification of the bacteriological techniques hitherto proposed in order to evaluate in vitro and in vivo the antibacterial interaction of chemoantibiotics. The third part is devoted to the classification and critical analysis of biometrical techniques hitherto applied to above quoted bacteriological techniques in order to obtain a quantitative evaluation of interaction. Criticism versus isobolic model is pointed out. In the final part a new procedure, named isoeffectual, is proposed. According to such a procedure a close grid of single and joint concentrations of a couple of chemoantibiotics, broad enough in order to cover the whole of the effects to be explored, is tested in vitro adopting the one-center agar diffusion test or a liquid medium. The experimental data so obtained are related in a planar diagram to the log of the sum obtained by adding to the concentrations of the first the concentrations of the second agent, converted into equi-effectual concentrations of the first. By this way a series of curvilinear regressions is obtained, which may be all explained by a mathematical formula according which the data may be submitted to statistical analysis and elaborated in order to draw the parameters able to define quantitatively the interaction. The model so applied is discussed as a general model for joint drug action.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Urinary infection in urology. A rapid technique for confirmation of the diagnosis and the orientation of medical treatment (author's transl)].

A rapid technique for confirmation of the diagnosis and the orientation of medical treatment of urinary infection. Performance of direct antibiotic sensitivities on urine is a rapid (14 to 18 hours) procedure for determining the presence of organisms in the urine and seeking the antibiotic most active against them. In order to assess the value of the procedure, it was compared with classical bacteriological techniques. The correlation was found to be satisfactory. This procedure of direct sensitivity studies on urine is not in to way in competition with classical bacteriological techniques but is of great value in rapidly confirming the diagnosis of urinary infection and in the orientation of therapy. It eliminates a number of the justifications of blind treatment.

Anti-Bacterial Agents↗
PubMed1977

Diagnosis of acute bacterial pneumonia in Nigerian children. Value of needle aspiration of lung of countercurrent immunoelectrophoresis.

Eighty-eight Nigerian children with untreated, severe, acute pneumonia were investigated by standard bacteriological techniques (blood culture and culture of pharyngeal secretions) and by needle aspiration of the consolidated lung. Countercurrent immunoelectrophoresis (CIE) against grouped pneumococcal and Haemophilus influenzae type b antisera was carried out on serum samples from 45 patients. The aetiology of pneumonia was shown by examination of the needle aspirate in 70/88 patients (79%), by CIE in 9/45 patients (20%), and by blood culture in 4/36 patients (11%). Overall, a bacterial cause for pneumonia was shown in 73/88 patients (83%). The results of pharyngeal culture were misleading when compared with cultures of needle aspirates. The prediction of aetiology from the radiological appearance was alos inaccurate, even for labor pneumonia. Needle aspiration of the lung, with a low (5%) and minor complication rate, merits wider application in the diagnosis of acute pulmonary infections in children. Tradiational bacteriological techniques (blood culture and pharyngeal culture) are of very limited value. The place of CIE in the investigation of childhood pneumonia still needs thorough evaluation.

Acute Disease↗
PubMed1977

[The rapid detection and specific identification of bacterial antigens by electro-immunodiffusion in 80 cases of purulent meningitis (author's transl)].

The cerebrospinal fluid of 120 subjects, 80 of whom were suffering from a purulent meningitis, were examined comparatively by classical bacteriological techniques (direct examination and culture) and by electro-immunodiffusion. This procedure makes it possible to detect not only viable bacteria, but also capsular polysaccharide antigens. It revealed the diagnosis in 96.9% of cases of meningococcal, pneumococcal and Haemophilus meningitis, as against 80.3% positive results using classical bacteriological techniques, for the same organisms. Electro-immunodiffusion provides a rapid answer (20 minutes) and, amongst other things, makes it possible: - to confirm the serotype or capsular type within the species, - to determine the aetiological diagnosis in certain types of meningitis where diagnosis is rendered difficult by blind antibiotic therapy, - to quantify and follow over a period of time the levels of polysaccharide antigens in the cerebrospinal fluid and serum of the patients. The sensitivity and specificity of electro-immunodiffusion render it a technique of the future in the diagnosis of purulent meningitis. By virtue of its simplicity, it should become a routine examination.

Antigens, Bacterial↗
PubMedDate not supplied

Bacteriology of the chronically discharging middle ear.

Suitable bacteriological techniques revealed anaerobic bacteria in 38 (33%) of 114 chronically discharging middle ears. The genus Bacteroides was cultured from 25 ears. Aerobic bacteriology showed the predominance of staphylococci, facultative enteric gramnegative rods, diphtheroid bacilli and Pseudomonas species. Anaerobic bacterial cultures were always mixed with aerobic bacteria. 12 ears were culture-negative, and 9 of the 108 Gram-stained smers revealed no bacteria. No significant difference in bacteriology was noted between ears with or without local antimicrobial treatment, or between profusely draining or only moist ears. The ears with postoperative recurrent infection or with clinical suspicion of cholesteatoma grew anaerobes significantly more often, and were seldom sterile. Because anaerobic bacteria are frequently associated with chronic otitis media, their characteristics with regard to susceptibility to antimicrobials and to air must be remembered in the choice of therapy.

Bacteria↗
PubMed1978

Isolation of Mycoplasma hominis from blood cultures in patients with postpartum fever.

Eight women with postpartum fever are presented in whom Mycoplasma hominis was isolated from cultures of their blood. Clinical disease consisted of a mild although often prolonged febrile illness, and all but one recovered without appropriate antimicrobial therapy. Five patients demonstrated elevated convalescent titers of mycoplasmacidal antibodies. The isolates of M. hominis were recovered from routine blood cultures in the diagnostic bacteriology laboratory using blind subcultures to blood agar plates. These cases lend support to the concept that endometritis with M. hominis is a cause of postpartum fever and suggest that these organisms may be recovered with increased frequency if minor changes in standard bacteriologic technique are introduced.

Bacteriological Techniques↗
PubMed1978

Wound infections and systemic antibiotic prophylaxis in gynecologic surgery. A review.

The gynecologic literature was reviewed and yielded 11 well-designed and well-conducted studies since 1960 involving the use of systemic prophylactic antibiotics. Five had significant results that support using prophylactic antibiotics in vaginal hysterectomy while three supported prophylaxis in cesarean sections. A cephalosporin agent is effective as a prophylactic agent and should be administered 2 hours before surgery by the intravenous route and discontinued 24-72 hours after surgery. A change in the bacteriologic flora of the cervical cuff occurs after surgery with an increase in E. coli and enterococci and a decrease in coagulose negative staphylococci and steptococci. Future studies should be randomized, prospective, and performed in a double-blind manner with antibiotics begun preoperatively. Special attention should be given to bacteriologic techniques, especially the search for anaerobic pathogens.

Anti-Bacterial Agents↗
PubMed2026

Improving isolate recovery and identification of the Shiga toxin type in Shiga toxin nucleic acid test-positive feces.

UNLABELLED: Infections caused by Shiga toxin-producing Escherichia coli (STEC) strains carrying Shiga toxin 2 (stx2) are more likely to result in severe complications; however, most nucleic acid amplification tests used for STEC diagnosis do not differentiate between stx1 and stx2. We therefore sought to optimize stx typing and isolate recovery methods to guide clinical and public health management. stx polymerase chain reaction (PCR)-positive feces were cultured using CHROMagar STEC and gram-negative broth, with Stx1 and/or Stx2 antigen detection by enzyme immunoassay (EIA) on colony growth or turbid broth. When cultures were EIA-negative, growth from MacConkey agar (MAC), Trypticase soy broth, and the gram-negative broth was then tested using a lab-developed typing PCR for stx1 and stx2. Colonies were isolated on CHROMagar STEC or MAC and identified using the typing PCR. Using both EIA and typing PCR, the stx types were identified in 96.0% of cases (381/397). In 65.2% (259/397) of cases, culture was EIA-positive, of which 34.0% (87/256) were Stx2-positive. Among cultures that were EIA-negative but typing PCR-positive, 64.8% (79/122) were stx2-positive (P < 0.0001 compared to EIA-positive). Using both EIA and typing PCR resulted in 72.6% (286/394) of cases with successful attempts at isolate recovery, compared to 60.7% (239/394) with EIA alone. E. coli O157 was recovered from more EIA-positive cases (19.3%, 46/239) than EIA-negative ones (4.3%, 2/47) (P = 0.0097). Typing PCR on cultures improves stx typing (particularly stx2) and isolate detection compared to EIA alone. Screening BD Max PCR and subsequent typing PCR results showed excellent concordance. IMPORTANCE: Escherichia coli strains with one or both types of Shiga toxins (stx1 and stx2) are a common cause of bacterial diarrhea and can lead to serious complications such as kidney failure, especially in children. Infection by stx2-positive strains is more likely to do so. Therefore, knowing whether the infection is caused by a strain carrying stx2 is important for risk assessment and case follow-up. The conventional way to diagnose these infections is to grow the bacteria from stool, but most laboratories currently use nucleic acid detection (e.g., bacterial DNA detection by polymerase chain reaction [PCR]), and these assays do not differentiate between the two toxin genes. Culture is therefore required to determine toxin type, as well as for public health outbreak investigations, which require an isolate for whole-genome sequencing for serotyping and cluster analysis. We identified culture media and a PCR-based method to detect stx2 in culture that improved the detection of stx2 and isolate recovery. Our findings provide more accurate results for clinicians to improve patient care and tools for public health teams to control and prevent outbreaks.

Humans↗
PubMed1975

Clinical aspects of anaerobic infections in the surgical patient.

Oxygen-sensitive anaerobic bacteria comprise the largest group of organisms among the human endogenous microflora. The oral cavity, vagina and colon are the areas where obligate anaerobes are predominant and can be isolated in very high numbers. Sepsis following surgery of any of these organs is frequently due to the escape of endogenous bacteria during the course of the operative procedure. To isolate and successfully identify most of these anaerobic microorganisms from clinical exudate, special collection and bacteriologic techniques are necessary. The acceptable anaerobic collection techniques mentioned above minimize exposure of the clinical specimen to atmospheric oxygen during collection and transfer. Clinical clues indicating anaerobic sepsis include a putrid odor of the exudate and evidence of abscess, necrosis or associated gas formation. The importance and value of the Gram stain in early identification of surgical sepsis is stressed. Treatment of infectious complications includes surgical drainage and specific antibiotics.

Abdomen↗
PubMed1976

Comparison of bacteriological methods for the isolation of group of B Streptococcus from vaginal cultures.

Three bacteriological techniques for the isolation of group B streptococci in vaginal cultures were compared. A selective broth medium (SBM) containing gentamicin and nalidixic acid was more sensitive for the detection of vaginal isolates (28/76, 36.8%) from 76 women enrolled in a venereal disease clinic than was an identical selective plate medium (SPM) (17/76, 25%). Similarly, SBM allowed identification of positive cultures from college women (82/459, 17.9%) significantly more often than direct inoculation of swabs onto nonselective blood agar medium (43/460, 9.4%; chi2 = 42.2, P = less than 0.001). Failure to isolate group B streptococci detected in SBM occurred in 32.1% cultures by SPM and 49.4% of cultures by nonselective agar medium. Multiple serotypes were detected in a single vaginal culture from approximately 5% of the patients studied. These data support the routine use of SBM for the most accurate identification of women vaginally colonized with group B Streptococcus.

Bacteriological Techniques↗
PubMed1976

Improved chamber for the isolation of anaerobic microorganisms.

A small portable chamber for the recovery of anaerobic bacteria is described. This rigid chamber is constructed of clear acrylic with dimensions of 30 inches (ca. 76.2 cm) wide, 18 inches (ca. 44.7 cm) deep, and 18 inches (ca. 44.7 cm) high. Conventional bacteriological techniques can be used inside the chamber to efficiently isolate strict anaerobic organisms. An adapter allows the attachment of a standard anaerobic jar to the outside of the chamber. The jar can be used to store reduced media. Once the jar is attached to the chamber and the media is removed to the interior of the chamber, the jar is available to receive inoculated media. The anaerobic jar can then be removed from the chamber, without contaminating the jar or chamber with oxygen, and be placed in a conventional 37degreesC incubator. This chamber also allows the microbiologist to process cultures without wearing gloves as was necessary with previous anaerobic chambers. Air-tight latex rubber sleeves seal around the microbiologists arms and to the armport flange of the chamber to prevent the introduction of oxygen into the chamber. Anaerobic conditions are maintained by circulating a 80% N2, 10% H2, 10% CO2 gas mixture through alumina pellets coated with palladium. This study indicates that anaerobic conditions obtained in this chamber are sufficient for recovery of obligate anaerobes.

Anaerobiosis↗
PubMed1976

[Mutual relations between plastic materials and bacteria (author's transl)].

The complex problems of microbiological degradation of synthetic plastics and a fairly wide variety of 62 testing materials, belonging to 14 major groups of plastics, are described. Adaequate and reliable testing techniques had to be devised. Drawing on the experiences of H. Braun, 1930, and of Bushnell and Haas, 1941, as to the metabolism of bacteria and the utilization of certain hydrocarbons by microorganisms, and previous research work by A. Schwartz in Berlin, 1959-60, on microbial corrosion of plastics, methods of laboratory testing were developed. The bacteriological technique was based on selection of aerobic microorganisms, which were, by starvation, adapted to use the plastic materials as their only carbon source; foreign carbon sources had to be strictly eliminated; emphasis was laid on proper, double control cultures. The test organisms involved included P. aeruginosa and fluorescens strains, also a certain species of Candida, and mixtures of soil, sewage and garbage organisms grown on exposed plastic surfaces. By means of series of passages the selective adaptation and conservation of these organisms was continued up to 4 1/2 years. An anaerobic adaptation method for Desulfovibrio desulfuricans was developed and used successfully. After preliminary experimentation (Soil burial, sewage and garbage exposure tests) in the laboratory as well as in the open, a large scale Field testing programme under realistic and to some extent extreme conditions was implemented: Nine different plastic materials comprising eight plain high polymer plastics and for comparison one synthetic Cellulose derivate, together with glass control samples, were exposed in twelve different sewage, garbage, and soil media over a period of 3 months to 2 years, and subsequently examined. On the basis of the bacteriological results obtained from the adaptation series the test materials were classified into three categories, corresponding to the stimulation of bacterial growth: Group one, which allowed strong proliferation, included certain types of plasticized P.V.C. and Cellulose esters, as expected, and, as a new result, Polyurethane rubber; the latter showed clear signs of surface corrosion. Group two, which induced a clear but moderate growth, comprised a nylon trade type of Polyamide. Gruop three, allowing weak but still recognisable growth, included Formaldehyde pressure resing (Bakelite). This was surprising as it was thought that the formaldehyde and phenol components would exert a bacteriocidic or at least bacteriostatic effect. The results of the long and time consuming adaptation series with Pseudomonas aeruginosa were confirmed by the manometric dissimilation method of O. Warburg by means of the Braun/Melsungen apparatus. With this subtle but elegant procedure results and graphical recordings were obtained within hours and days...

Candida↗
PubMed1977

Effect of a Ca(OH)2 solution and a chlorhexidine based detergent on the microbial activity of human carious teeth.

Occlusar carious lesions from human molars, preserved in continuous humidity after extraction, were removed using conventional clinical techniques. Bacteriological samples were taken after rinsing the cavity with water only, after experimentally infecting the cavity and after treating uninfected cavities either with a saturated Ca(OH)2 solution or with a chlorhexidine based detergent. The samples were cultivated on blood agar plates aerobically and anaerobically. Cavities rinsed with water only showed very sparce bacterial growth. After experimental infection the growth was significant, but decreased radically after treatment with the test materials. In order to describe the effect of the two test materials on the microbial enzyme activity in infected dentin, cryostat sections of 10 micrometer were prepared from undermineralized carious dentin fragments excavated from freshly extracted human teeth. Conventional histochemical techniques were applied to demonstrate the aminopeptidase activity in the sections using N-L-leucyl-2-naphthylamide as a substrate. The aminopeptidase activity of carious dentin was inhibited totally with the Ca(OH)2 solution, whereas the chlorhexidine based detergent had no effect on the enzyme activity.

Aminopeptidases↗
PubMed1976

Kinetics of the actions of tetracyclines on Escherichia coli as studied by microcalorimetry.

Microcalorimetry was used to study the kinetics of the actions of various tetracyclines on a strain of Escherichia coli. Differences in the capacity to suppress the metabolism of this bacterium were observed. When the antibiotic was present from the start of the experiment, a heat production of 2.0 muW/ml was registered after 12.5 h using minocycline; the corresponding figures for doxycycline, oxytetracycline, and tetracycline were 7.3, 6.6, and 4.5 h, respectively. In these experiments, equal concentrations, i.e., half the minimum inhibitory concentration (MIC), of each drug were used. The MIC for all the tetracyclines tested, determined by the broth dilution technique, was 0.8 mug/ml. In other experiments, the antibiotic (concentration, 1.6 mug/ml = 2x MIC) was introduced into the growth vessel during the logarithmic growth phase of the organism. The extent and duration of the inhibitory effect on the metabolism, as judged from the decrease in heat production, varied with the different tetracyclines. Immediately after introduction, minocycline, doxycycline, oxytetracycline, and tetracycline decreased the heat production in decreasing order of potency. With tetracycline, the heat production rose after about 1 h, and with minocycline it rose after about 9 h. The heat production remained at a low level for at least 19 h when using doxycycline and oxytetracycline. The results indicate that microcalorimetry offers a means for studies of the kinetics of the antibacterial actions of antibiotics and provides information that cannot be obtained by conventional bacteriological techniques. This information may be of use, in conjunction with pharmacokinetic data, in establishing optimum doses and dose intervals in antibiotic therapy.

Calorimetry↗
PubMed1979

Staphylococcal septic arthritis in three horses.

Three horses were diagnosed as having monarticular septic arthritis due to Staphylococcus aureus on the basis of culture of articular cartilage, synovial membrane and/or synovial fluid. The organisms were all well recognised human phage types and in two cases demonstrated beta-lactamase (penicillinase) activity. Details of case histories are presented and the bacteriological techniques and antibiotic management with cloxacillin, methicillin and penicillin discussed. Following treatment, sterile cultures of synovial fluid were achieved in all cases, but in two horses the infections resulted in degenerative articular changes. This necessitated arthrodesis of the fetlock joint in one case.

Animals↗