[Comparison of two phenotypic methods for detecting the production of extended-spectrum beta-lactamases by hospital Klebsiella pneumoniae strains].

In the period 2006-2008, the Republican Emergence Medical Care Center.isolated 2997 enterobacteria, 48.9% of which belonged to Klebsiella pneumoniae. Confirming phenotypic methods, such as double disk method (DDM) and double disk synergy test (DDST), were used to examine 64 K. pneumoniae strains that had been regarded as being suspected to produce extended-spectrum beta-lactamases (ESBL) during a preliminary screening. Of the 64 K. pneumoniae strains, 6 (9.4%) were unsusceptible to clavulanate and not referred to as ESBL producers and 5 (7.8%) were resistant to imipenem. DDM ranks below DDST as it (concurrently with DDST) yielded positive results only in 30 (51.7%) strains; 28 (48.3%) cultures were positive only with DDST - these strains were significantly more frequently resistant to three third-generation test cephalosporins during primary screening.

[Experimentally determined safety and immunological activity of vaccine based on antigens isolated from Pseudomonas aeruginosa in medium K-4].

The safety and immunological activity of P. aeruginosa vaccine were experimentally evaluated. The vaccine was prepared on the basis of the antigens of P. aeruginosa extracellular slime which was accumulated in medium K-4, obtained with the use of original technology. The immunization of animals with P. aeruginosa vaccine induced the synthesis of antibodies. The introduction of the vaccine in 2 or 3 injections resulted in a high level of antibody formation, differing with the use of various strains. Hyperimmune sera, obtained by the multiple immunization of rabbits with P. aeruginosa vaccine, ensured high protection of mice from P. aeruginosa infection. The vaccine proved to be safe when evaluated in experiments of acute and chronic toxicity, made on laboratory animals.

[Species affiliation of staphylococci isolated in purulent infections]. / Vidovaia prinadlezhnost' stafilokokkov, vydelennykh pri gnoinykh infektsiiakh.

The microflora was studied of the clinical material taken from those patients presenting with different pyo-septic diseases. It has been ascertained that a key role in the etiology of the above diseases must be referred to gramme-positive micro-organisms--to coagulase-negative staphylococci among their number. Of these, S. haemolyticus and S. epidermidis were found with high frequency.

[Modified method of inoculation of hemocultures from patients with suppurative-septic diseases and typhoid-paratyphoid fever]. / Modifikatsiia metoda poseva gemokul'tur of bol'nykh gnoino-septicheskimi zabolevaniiami i tifo-paratifami.

A modified method of isolating hemocultures in pyoseptic processes is proposed. It consists in combined use of two known methods: inoculation of the blood by in-depth method and preliminary hemolysis of the blood, and use of commercial medium for assessing the sterility as the nutrient base. High efficacy of the proposed method has been demonstrated in experiments with 17 reference strains of microorganisms. The new approach helped improve the isolation rate of opportunistic enterobacteria, nonfermenting gram-negative bacteria, staphylococci, highly demanding streptococci, and other microorganisms similar in nutrient requirements, as well as the agents of typhoid and paratyphoid fever. This permits unifying the methods of investigation of hemocultures in pyoseptic diseases and typhoid-paratyphoid fevers'.

[Hospital strains of Pseudomonas aeruginosa in the surgical clinic]. / Gospital'nye shtammy Pseudomonas aeruginosa v khirurgicheskoi klinike.

Circulation of different antigenic variants of P. aeruginosa in a surgical hospital was studied. In this study the process leading to the formation of pathogenic hospital strains, determined by time and location, from some serovars is demonstrated. The study also established that the department of the hospital where the selection of hospital strains mainly occurred was the resuscitation ward. Some pyoseptic infections of P. aeruginosa etiology with fetal outcome were found to be caused in most cases by hospital strains characteristic of the hospital in the period under study.

[Improving the clinico-microbiological diagnosis and treatment of non-clostridial anaerobic peritonitis]. / Sovershenstvovanie kliniko-mikrobiologicheskoi diagnostiki i lechenia neklostridial'nogo anaérobnogo peritonita.

On the basis of clinico-microbiological examinations the presence of anaerobic flora was found in 104 out of 198 patients with peritonitis. The authors propose using intra-aortal++ transfusions of oxygenated blood in complex therapy of anaerobic peritonitis.

[The role of non-clostridial anaerobic infections in the etiology, pathogenesis, clinical aspects and treatment of inflammatory diseases of the paranasal sinuses]. / Rol' neklostridial'noi anaérobnoi infektsii v étiologii, patogeneze, klinike i lechenii vospalitel'nykh zabolevanii okolonosovykh pazukh.

This paper presents the results of clinical and bacteriological examinations of 116 patients with suppurative rhinosinusitis. Bacteriological tests under anaerobic conditions revealed in 53% of the patients nonclostridium anaerobic bacteria that were highly resistant to most antibiotics and sensitive to metronidazole and its derivatives. A protocol of conservative therapy of suppurative rhinosinusitis was developed. The protocol included etiotrophic antianaerobic drugs (metronidazole and its derivatives) and oxygenation of paranasal sinuses. This therapeutic approach yielded positive effects in 92% of the patients.

[Seasonal changes in the frequency of isolating strict anaerobes in purulent-inflammatory processes]. / Sezonnye izmeneniia chastoty vydeleniia strogikh anaérobov pri gnoino-vospalitel'nykh protsessakh.

Seasonal changes in the isolation rate of obligate anaerobes from the pathological material of patients with purulent inflammatory diseases were studied. For this purpose 707 samples of pathological material were analysed in the course of 1982-1986. Anaerobes were detected in 160 samples, which constituted 22.6% of all samples under study and 33.5% of the samples showing microbial growth. A statistically significant increase in the isolation rate of anaerobes from pathological material at the period of March-April was established. It was considered expedient to regard this newly found effect as an additional risk factor in the appearance of anaerobic infections and to take it into account in planning and carrying out prophylactic and diagnostico-therapeutic measures.

[Improving the microanaerostat model MI-752 and manufacturing simple microanaerostatic devices for cultivation of anaerobes]. / Usovershenstvovanie mikroanaérostatov modeli MI-752 i izgotovlenie prostykh mikroanaéristatnykh ustroistv dlia ku'ltivirovaniia anaérobov.

The improvements in the design of the MI-752 microanaerostat, manufactured in this country, are aimed at improving its security. These microanaerostats are recommended to be supplied with seamless cases of various volumes or the rigidity of the case fragments attachment be strengthened with bolts. Unsophisticated devices, high-volume anaerostat and ultramicroanaerostat, are suggested. The former is made of a glove steam sterilizer prechamber, the latter of a glass can, 0.5-0.8 1 volume, with a hermetically screwing lid. Both anaerostats are supplied with 2 taps to be filled with oxygen-free gas mixtures. These apparatuses are simple, convenient, reliable; among their advantages are glass walls and the possibility to do without vacuum pumps.

[Microbiological diagnosis of pyo-inflammatory processes caused by strictly anaerobic microorganisms]. / Mikrobiologicheskaia diagnostika gnoino-vospalitel'nykh protsessov, vyzvannykh strogo anaérobnymi mikroorganizmami.

Basing on the literature data and their own findings, the authors have attempted a rational arrangement of the microbiologic diagnosis of anaerobic infections. The precultural and cultural stages of the diagnosis have been singled out. A hypothetic diagnosis is put forward at stage I; it is based on the sum of the clinical symptoms of anaerobic infections and on the microscopy of the native material. During the cultural stage the anaerobe colonies indication is performed in the primary inoculation dish by the technique developed by the authors; preliminary identification of the colonies is made here too. Then the obtained subcultures are finally identified according to relevant schemes and to a table with the differentiating markers. The suggested scheme accelerates and simplifies the laboratory diagnosis of anaerobic infections.

[Antibiotic sensitivity of nonfermenting gram-negative bacteria]. / Chuvstvitel'nost' k antibiotikam nefermentiruiushchikh gramotritsatel'nykh bakterii.

Antibiotic resistance of 132 strains of nonfermenting gram-negative bacteria (NGNB) was studied. 43, 20, 17, 14 and 12 of them belonged to Acinetobacter calcoaceticus (anitratus and lwoffi), Pseudomonas cepacia, Alcaligenes faecalis, P. stutzeri and P. maltophilia, respectively. With rare exceptions all the strains were resistant to benzylpenicillin, oxacillin, lincomycin, ampicillin and cephaloridine. Sensitivity to the other antibiotics varied within wide ranges. Amikacin (94.3 per cent) and tobramycin (90.8 per cent), as well as polymyxin, rifampicin and gentamicin (71.7-66.9 per cent) had the highest effect. The majority of the antibiotics had higher activity (p less than 0.01) against the tested NGNB as compared to their activity against P. aeruginosa. Antibioticograms of every of the tested species of NGNB revealed that P. cepacia and P. stutzeri were the most resistant species. The biovars of Acinetobacter varied in their antibiotic resistance: A. subsp. lwoffi was more sensitive to the majority of the antibiotics though some of them, i.e. doxycycline, carbenicillin, and polymyxin were more active against A. subsp. anitratus.

[Sensitivity of clinical strains of facultatively anaerobic bacteria to antimicrobial drugs]. / Chuvstvitel'nost' klinicheskikh shtammov obligatno anaérobnykh bakterii k antimikrobnym preparatom.

Six hundred and sixty five samples of clinical materials from patients with various pyoinflammatory diseases were tested for obligatory anaerobes. Anaerobes were detected in 148 samples which amounted to 22.3 per cent of the total number of the samples and to 33.2 per cent of the samples with microbial growth. A total of 171 strains of obligatory anaerobes were isolated. Among them 58.5, 24.5, 16.4 and 0.6 per cent were nonsporulating gramnegative bacilli, grampositive cocci, grampositive bacilli and gramnegative cocci respectively. Sensitivity of the isolated anaerobes was tested with the disk diffusion method. The most active drugs against the tested strains were: nitroxoline, rifampicin, metronidasole, erythromycin, carbenicillin and cefotaxim (4.2, 4.5, 9.3, 10.6, 11.5 and 11.7 per cent of the resistant strains respectively). Gentamicin, polymyxin M, novobiocin and cefazoline were the least active drugs (94.6, 78.9, 65.4 and 50.0 per cent of the resistant strains respectively). Metronidasole, levomycetin, nitroxolin, rifampicin and furazolidone showed the highest activity against bacteroids of the fragilis group (0, 0, 0, 8 and 12.5 per cent of the resistant strains respectively) while gentamicin, polymyxin M, cefazolin, oxacillin, novobiocin and penicillin showed the lowest activity (100, 100, 100, 100, 87.0 and 66.7 per cent of the resistant strains respectively).

[Method for demonstrating strict anaerobes in microbial associations]. / Metod indikatsii strogikh anaérobov v mikrobnykh assotsiatsiiakh.

A procedure for indicating strict anaerobes in microbial associations was developed. The indication is performed with two disks: aminoglycoside (amikacin, 10-micrograms disk) (A) and metronidazole aminoglycoside (metronidazole + amikacin, 5- and 10-micrograms disks respectively) (MA). Colonies growing in zone A and absent in zone MA are considered to be strictly anaerobic. The procedure is characterized by high reliability: false positive results are practically not recorded and the frequency of false negative results does not exceed 5-10 per cent. The rate of detecting anaerobes in clinical materials is significantly increased (by 1-3 days) as compared to that with the use of the routine bacterial methods. The indication procedure markedly simplifies laboratory diagnosis of anaerobic infections at the account of clear differentiation of microorganisms grown on the primary plate and possible directed selection of anaerobic colonies for further investigation which excludes the necessity of rejecting or studying other colony types. This leads to economy of nutrient media and increasing labor productivity.

[Antibiotic resistance of clinical strains of Pseudomonas aeruginosa from various O-serogroups]. / Antibiotikorezistentnost' klinicheskikh shtammov Pseudomonas aeruginosa raznykh O-serogrupp.

The results of the study on antibiotic resistance of 745 strains of P. aeruginosa isolated in hospitals from surgical patients, environment and carriers are presented. 89.7 per cent of the strains were typed by the commercial O-sera. The isolates were most sensitive to tobramycin (99 per cent), amikacin (95.1 per cent), cefsulodin (95.1 per cent), polymyxin (89.7 per cent) and gentamicin (73.5 per cent). Comparison of the antibiotic resistance of the typed and nontyped cultures revealed that the former were more resistant to tetracycline, carbenicillin, rifampicin, kanamycin and cefotaxim, while the latter were more resistant to gentamicin and polymyxin. It was also noted that the proportion of the strains resistant to all of the tested antibiotics was higher among the nontyped cultures. Antibiotic sensitivity of P. aeruginosa was in many respects defined by the strain origin: the strains isolated from patients were more resistant to tetracycline, carbenicillin, rifampicin, cefotaxim and kanamycin and more sensitive to gentamicin and polymyxin than the strains isolated from the environment. The cultures belonging to different O-serogroups (O-11 and O-2) markedly differed by their antibioticograms.

[Characteristics of hospital strains of Pseudomonas aeruginosa]. / Kharakteristika gospital'nykh shtammov Pseudomonas aeruginosa.

A total of 745 P. aeruginosa strains from patients with purulent inflammatory processes, 216 strains from the environment of a surgical hospital and 35 strains from carriers were studied with respect to 30 cultural and biochemical signs of P. aeruginosa. 19.8% of the strains were found to form no pigment, and in 14.8% of the strains delayed pigment formation was observed (on days 3-10). The most stable signs were motility (99.6%), growth in Simmons citrate agar (97.6%), growth at 42 degrees C (97.4%), arginine decarboxylase activity (96.8%). In 77.0% of the strains glucose assimilation in Hiss liquid medium, in 85.6% glucose oxidation in the OF test, in 90.8% the formation of urease and in 93.2% the formation of gelatinase were observed. Among the strains isolated from the environment, P. aeruginosa variants, atypical with respect to their main differentiating signs, were isolated significantly more frequently.

[Aerobic and facultatively anaerobic bacteria isolated from surgical infection patients]. / Aérobnye i fakul'tativno-anaérobnye bakterii, vydelennye ot bol'nykh s khirurgicheskoi infektsiei.

The ecological structure of infections in surgical patients with different postoperative complications (suppurative wounds, abscesses, peritonitis, etc.) and suppurative lung diseases were studied. During the period of 6 years (1975-1980) 5401 samples of clinical material were studied. 1380 samples (25.6%) were sterile, from 2254 samples (41.7%) monocultures were isolated, in 1767 samples (32.7%) microbial associations were detected. Of 5962 isolated cultures, 1816 (30.5%) were Gram-negative bacteria (GNB), 3532 (59.2%) were Gram-positive bacteria (GPB) and 614 (10.6%) were yeastlike fungi. The tendency towards the increase of the role of GNB in the etiology of postoperative complications was observed. Among GNB Pseudomonas aeruginosa strains were prevalent (36.2%). In the group of GPB coagulase-negative staphylococci were rather frequently found to be the causative agents of surgical infections.