Spread and control of methicillin resistant Staphylococcus aureus in a department of dermatology

Patients with skin diseases caused a spread of methicillin-resistant Staphylococcus aureus (MRSA) to 17 patients in our Department of Dermatology, because of their heavily scaly skin. Patients with severe dermatosis are regularly treated with dicloxacillin. The resistance of bacteria strain concerned suggests a selection because of the use of dicloxacillin in the Department. The strain is sensitive to gentamicin, which differentiates it from strains imported from abroad. Increased hygienic precautions, isolation of infected patients, staff and management efforts and a close contact with the microbiologists prevented MRSA from spreading to other hospital wards.     

Genesis of methicillin-resistant Staphylococcus aureus (MRSA), how treatment of MRSA infections has selected for vancomycin-resistant Enterococcus faecium, and the importance of antibiotic management and infection control

We extensively studied the epidemiology and time course of endemic methicillin-resistant Staphylococcus aureus (MRSA) in the Millard Fillmore Hospital, a 600-bed teaching hospital in Buffalo. The changeover from methicillin-susceptible S. aureus to MRSA begins on the first hospital day, when patients are given cefazolin as presurgical prophylaxis. Under selective antibiotic pressure, colonizing flora change within 24 to 48 hours. For patients remaining hospitalized, subsequent courses of third-generation cephalosporins further select and amplify the colonizing MRSA population. Therefore, managing antibiotic selective pressure might be essential. Other strategies include attention to dosing, so that serum concentrations of drug exceed the minimum inhibitory concentration, and antibiotic cycling. Although there are some promising new antibiotics on the horizon, it is necessary to deal with many resistance patterns by using the combined strategies of infection control and antibiotic management.     

Typing, resistance behavior and occurrence of methicillin-resistant Staphylococcus aureus strains in a surgical intensive care unit

Over a period of three years, the frequency of the appearance of methicillin-resistant S. aureus strains (MRSA) was observed on a surgical intensive care unit. During this above-mentioned period of investigation it came to a heaped occurrence of nosocomial infections on this ICU with altogether 332 S. aureus-stems being isolated from different patient specimen. 204 (61.5%) of these were resistant against methicillin and could be divided into 48 first- and 156 follow-up-isolates. The thereupon accomplished differentiation of the 48 MRSA-first isolates by means of lysotyping and the pioneered GenePath Strain Typing System for a standardized pulsed-field-gel-electrophoresis (PFGE) gave the proof of 7 different MRSA-types. Around 7 different, in part parallel chains of infection on this ICU were observed, which could be led back to different strains. In reference to all analyzed S. aureus, an especially high rate (90%) of MRSA on this ICU could be isolated in taken wound-swabs, followed by 83.3% MRSA at catheter tips and 71,9% in tracheal and bronchial secretion. A consideration of the antibiotic susceptibility yielded, that also gentamicin and the quinolones showed an in-vitro resistance against MRSA, while fosfomycin, fusidic acid, chloramphenicol and trimethoprim/sulfamethoxazole reached positive responding rates between 80 and 100%. On the other hand, presently still 100% of the explored MRSA-strains are susceptible for glycopeptides such as vancomycin and teicoplanin. Because of intensive hospital hygienic measures the number of newly isolated MRSA could be reduced clearly on this ward.     

Bronchial embolization in the treatment of hemoptysis

The aim of this retrospective study was to evaluate the efficacy of bronchial artery embolization to treat hemoptysis. Eight hundred sixty-five patients were admitted to our hospital with hemoptysis during the study period. Bronchial arteriographs were obtained for 48, who suffered life-threatening hemoptysis refractory to medical treatment. The likely origin of bleeding was identified in 37: embolization was performed with particles measuring 250 to 1000 micra in size (Contour Emboli, Interventional Therapeutic Corporation, South San Francisco, California, USA) in 35 and with hemostatic collagen sponges in 2. The most common causes of hemoptysis were bronchiectasis (40%), pulmonary tuberculosis (33%), pulmonary aspergilloma (8%) and malignant neoplasm (8%), chronic bronchitis (6%); 4% of the cases were idiopathic. Immediate technical success was achieved in 34 patients (92%) as defined by the absence of hemorrhage for at least 24 hours. All embolized patients were followed until the first recurrence of bleeding or until discharge. Recurrence of hemoptysis (in the first month) was early in 5 patients (13.5%) and late (2 to 96 months) in 9 (24%). The severity of the initial and later episodes of hemoptysis was similar in all early recurrences and most late recurrences. A second embolization was performed six times, and medical and/or surgical treatment was given in all other cases. No significant complications attributable to the technique were observed. The results show that bronchial embolization is valid for the immediate control of life-threatening hemoptysis and has a low rate of severe complication; recurrence is relatively common.     

Postoperative enteritis caused by methicillin-resistant Staphylococcus aureus

We examined the clinical features of 14 men (mean age 72 years) with postoperative enteritis caused by methicillin-resistant Staphylococcus aureus (MRSA). The patients had all undergone surgery for the treatment of digestive diseases and had received antibiotic prophylaxis consisting of an extended-spectrum cephem. Diarrhea appeared a mean of 3.3 days postoperatively and lasted for 5 days on average. In severe cases organ insufficiency was involved. Coagulate-positive staphylococci were the predominant organisms isolated from watery diarrhea. In 13 of 14 patients, coagulase type II isolates producing enterotoxins A, C and toxic shock syndrome toxin-1 (TSST-1) with enterotoxin A, C, and 1st genes were isolated. These strains were sensitive to vancomycin and arbekacin; however, they were highly resistant to many other antibiotics. We also investigated the effects of a glucocorticoid hormone and gamma globulin on production of tumor necrosis factor-alpha (TNF-alpha) and interleukin-2 (IL-2) obtained from healthy volunteers. TNF-alpha and IL-2 production was enhanced by TSST-1 and the supernatant of Iscove-modified dulbecco medium, in which coagulase type II isolates producing enterotoxins A, C and TSST-1 with enterotoxin A, C were cultured for 24 h. Both glucocorticoid hormone and gamma globulin suppressed TNF-alpha and IL-2 production, thus suggesting that these drugs may be effective in treating postoperative MRSA enteritis.     

Analysis of an outbreak of non-phage-typeable methicillin-resistant Staphylococcus aureus by using a randomly amplified polymorphic DNA assay

A cluster of methicillin-resistant Staphylococcus aureus (MRSA) infections among patients on an intensive care unit (ICU) was detected by routine infection control surveillance. In the period from 5 January to 22 June 1995, 10 patients on the ICU and a further 6 patients (5 on one ward that had received colonized patients transferred from the ICU) were affected by MRSA strains with the same antibiotic susceptibility patterns. Seven (44%) of these 16 colonized patients developed MRSA bacteremia. MRSA isolates with the same characteristics were also found on the hands of one member of the ICU staff. The isolates were untypeable by phage typing, but 15 of 17 outbreak strains analyzed genetically had identical randomly amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) profiles. A single strain of MRSA that was nontypeable by phage typing and that was isolated on the ICU on 1 January and six nontypeable and epidemiologically unrelated MRSA isolates all had RAPD profiles distinct from that of the outbreak strain. Implementation of strict infection control measures stopped the further spread of MRSA on the ICU, the affected general ward, and seven other wards that received MRSA carriers from the ICU. Although nontypeable by phage typing and not previously recognized as an epidemic strain, this strain of MRSA was readily transmissible and highly virulent. RAPD typing was found to be a simple, rapid, and effective method for the epidemiological investigation of this outbreak, and performance of typing by this method was simpler and less time-consuming than that of typing by PFGE. RAPD typing may have more general application for the study of S. aureus infections in hospitals.     

Randomized double-blinded trial of rifampin with either novobiocin or trimethoprim-sulfamethoxazole against methicillin-resistant Staphylococcus aureus colonization: prevention of antimicrobial resistance and effect of host factors on outcome

Methicillin-resistant Staphylococcus aureus (MRSA) is a major pathogen in hospitals. Current antimicrobial regimens for eradicating colonizing strains are not well defined and are often complicated by the emergence of resistance. The combination of novobiocin plus rifampin in vitro and in vivo was found to prevent the emergence of resistant populations of initially susceptible strains of MRSA, particularly resistance to rifampin. We therefore studied, in a randomized, double-blind, multicenter comparative trial, the combination of novobiocin plus rifampin versus trimethoprim-sulfamethoxazole (T/S) plus rifampin in order to determine the efficacy of each regimen in eradicating MRSA colonization and to further characterize the host factors involved in the response to this antimicrobial therapy. Among the 126 individuals enrolled in the study, 94 (80 patients; 14 hospital personnel) were evaluable. Among the 94 evaluable subjects, no significant demographic or medical differences existed between the two treatment groups. Successful clearance of the colonizing MRSA strains was achieved in 30 of 45 (67%) subjects receiving novobiocin plus rifampin, whereas successful clearance was achieved in 26 of 49 (53%) subjects treated with T/S plus rifampin (P = 0.18). The emergence of resistance to rifampin developed more frequently in 14% (7 of 49) of subjects treated with T/S plus rifampin than in 2% (1 of 45) of subjects treated with novobiocin plus rifampin (P = 0.04). Restriction endonuclease studies of large plasmid DNA demonstrated that the same strain was present at pretherapy and posttherapy in most refractory cases (24 of 29 [83%] subjects). Among the 56 successfully treated subjects, clearance of MRSA was age dependent: 29 of 36 (80%) subjects in the 18- to 49-year-old age group, 19 of 35 (54%) subjects in the 50- to 69-year-old age group, and 8 of 23 (35%) in the 70- to 94-year-old age group (P < 0.01). Clearance was also site dependent; culture-positive samples from wounds were related to a successful outcome in only 22 (48%) of 46 subjects, whereas culture-positive samples from sites other than wounds (e.g., nares, rectum, and sputum) were associated with a success rate of 34 of 48 (71%) subjects (P = 0.02). Foreign bodies in wounds did not prevent the eradication of MRSA by either regimen. T/S plus rifampin was less effective in clearing both pressure and other wounds, whereas novobiocin plus rifampin was equally effective in clearing both pressure and other wounds. There were no significant differences in toxicity between the two regimens. Thus, the combination of novobiocin plus rifampin, in comparison with T/S plus rifampin, was more effective in preventing the emergence of resistance to rifampin and demonstrated a trend toward greater activity in clearing the MRSA carrier state. The response to either combination depended on host factors, particularly age and the site of MRSA colonization.     

A profile of methicillin resistant Staphylococcus aureus infection in the burn center of the Sultanate of Oman

A retrospective study of patterns of infection in 168 patients admitted during 1995 and 1996 in the burns-unit of Khoula hospital at Muscat, Oman was performed. Out of 819 isolates positive for pathogenic bacterial culture, there were 326 (39.8%) isolates positive for methicillin resistant Staphylococcus aureus (MRSA) infection. Incidence of MRSA infection was marginally more than that of Pseudomonas aeroginosa. The proportion of patients developing MRSA infection sometime or the other during their burns-unit stay ranging from 1 to 112 days rose from 48% in 1995 to 52.7% in 1996. No sophisticated tests were done to identify the MRSA strain but study of the antibiograms of each MRSA positive isolate showed very similar patterns of sensitivity to different antibiotics. This suggests the source of infection to be common and in all probability 'noscomial', since all patients acquired MRSA infection in the hospital. The susceptibility of MRSA to ciprofloxacin, cotrimoxazole and fucidin was 76, 51 and 37% of isolates in 1995, and 59, 44 and 26% in 1996 were susceptible to these drugs. Vancomycin was the antibiotic to which most MRSA cultures were susceptible, but partial resistance was reported due to very low susceptibility observed in 1.4% of the isolates in 1995 and 1.1% of the isolates in 1996. The control measures being practiced in the burns-unit of Khoula Hospital, especially mechanical cleaning and chemical disinfection of all surfaces, are discussed in detail. This paper emphasizes the need for preventive measures against MRSA infection in the burns-unit.     

A molecular epidemiologic study of methicillin-resistant Staphylococcus aureus infection in patients undergoing middle ear surgery

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections after middle ear surgery has recently increased at our hospital. Most of these infections were thought to be hospital-acquired when medical personnel in contact with an MRSA-infected patient may have inadvertently transmitted the pathogen to other patients. To prevent further transmission it is essential that such sources of MRSA infection and transmission routes be selected out and eradicated. Therefore, it is necessary to determine whether the strains of MRSA isolated from infected patients are identical to those obtained from medical personnel in order to prove a reciprocal transmission of organisms between medical personnel and patients. Surveillance bacterial cultures from the anterior nares and hands of medical personnel working in the Department of Otolaryngology, Korea University Guro Hospital, were performed at two different time points: 6 December 1994 and 17 June 1996. Ribotyping with Southern blot technique was used to compare 12 MRSA strains from medical carriers with 60 strains identified from the otorrhea of MRSA-infected patients undergoing middle ear surgery. As results, six different MRSA strains were identified (types I, II, III, IV, V and VI) from ribotyping with EcoR1. One distinct subtype, type I strain, was the most frequently identified strain in both medical carriers and patients. Results also showed that 6 MRSA isolates from 10 medical carriers and 20 from 30 patients contained type I ribotype at first culture. Two medical carriers' isolates and 13 isolates from 30 patients shared the same type I strain at the second surveillance culture. In all, 41 out of 72 MRSA strains (56.9%) shared an identical ribotype pattern. Postoperative MRSA infection rates after treatment of medical carriers and the application of rigorous preventive procedures decreased from 11.9 to 5.7% after first culture and 9.0 to 7.7% following second cultures. These findings confirm that MRSA transmission can occur between medical personnel and patients and that effective preventive measures can reduce the postoperative infection rate.     

Clonal heterogeneity, distribution, and pathogenicity of methicillin-resistant Staphylococcus aureus

Four thousand eighty-eight Staphylococcus aureus isolates obtained from patients hospitalised in a university clinic and four community hospitals over a period of one year were screened for methicillin resistance. A resistance rate of 5% was detected among initial isolates. Distribution of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus showed an increased prevalence of MRSA in clinically significant specimens such as blood, central venous catheter tips, bronchial secretions, and wound secretions. Typing of 110 MRSA strains (initial isolates) by macrorestriction analysis of chromosomal DNA revealed 26 different genotypes that could be divided into five epidemic and 21 sporadic strains. More than 50% of all isolates belonged to one type that was confirmed to be closely related to the "southern-German" epidemic strain. Production of virulence factors such as enterotoxin A-D and toxic shock syndrome-toxin 1 among MRSA strains (initial isolates) occurred in ten of 26 different MRSA types. A strong correlation between genotype and toxin production was demonstrated.     

Rostering: placing the nurse in the picture

The aim of the study was to find out whether methicillin-resistant S. aureus strains (MRSA) are tolerant in a higher degree to disinfectants, and whether a correlation exists between lower sensitivity to these agents and resistance to gentamicin. The study was carried out on 30 strains of MRSA and 20 of MSSA isolated from various clinical materials in various regions of the country. Among the studied MRSA 24 strains were resistant and 6 were sensitive to gentamicin, and in MSSA 3 strains were resistant and 17 sensitive to this antibiotic. The sensitivity to four disinfectants: Manusan, Sterinol, Septyl R and Lysoformin Spezial was determined by measurement of MIC (minimal inhibitory concentration) in agar medium. Most MRSA in Poland showed decreased sensitivity to these disinfectants. Among gentamicin-sensitive and resistant MRSA strains the proportions of strains with higher tolerance of three disinfectants (Manusan, Sterinol and Lysoformin Spezial) were very similar. Reduced sensitivity to disinfectants was found in all gentamicin-resistant MSSA. These data indicate that S. aureus strains possess various mechanisms of tolerance of disinfectants. Nearly half the studied strains (46%) had decreased sensitivity to all three preparations (Manusan, Sterinol and Lysoformin Spezial) belonging to various chemical groups this seems to indicate that increased tolerance to these disinfectants is a non-specific feature of S. aureus strains.     

Influence of thyroxine on different ion-dependent ATPase activities in fat body of tasar silkworm, Antheraea mylitta D

OBJECTIVES: To identify characteristics associated with methicillin-resistant Staphylococcus aureus (MRSA) colonization and infection, and to evaluate the efficacy of systemic and topical antimicrobials in the eradication of MRSA carriage among hospitalized patients. DESIGN: A case-control study was done to identify associations. Odds ratios were estimated by unconditional multiple logistic regression. Cohort study was done to evaluate MRSA decolonization efficacy by an oral regimen. Patients infected or colonized with MRSA received a 5-day course of oral (160 mg/800 mg) trimethoprim-sulfametroxazole twice daily and 600 mg of rifampin once daily as decolonization treatment. The proportion of MRSA-free patients after decolonization treatment was determined. Persistence of clearing was estimated by the Kaplan-Meier method. SETTING: Ramón y Cajal Hospital, a 1,249-bed, tertiary-care teaching hospital in Madrid, Spain. PATIENTS: One hundred ninety-two patients with hospital-acquired MRSA infection/colonization and 195 MRSA-free random controls. RESULTS: Six factors were associated independently with MRSA infection/colonization: age (every 10 years of age, odds ratio [OR] = 1.3); ward (surgical, OR = 1; medical, OR = 3.1; intensive care unit, OR = 60); previous hospitalization (OR = 6.9); coma (OR = 25.3); invasive procedures (each, OR = 1.7); 3 or more weeks of hospitalization (OR = 3.8). We failed to show antibiotic therapy to be an independent risk factor for MRSA hospital infection/colonization. Overall, MRSA eradication was 64.2% by day 2 to 9 after completion of treatment. Kaplan-Meier product limit survival analysis showed that the probability of remaining MRSA-free was 65.3% (SE = 0.09) at 32 days after completion of treatment. CONCLUSIONS: The results offer a rationale for reduction of MRSA infection/colonization in the hospital by interventions aimed at early identification of patients at higher risk, at prompt discharge of patients, and at preventing dissemination while performing invasive procedures. They also provide estimates of antibiotic treatment efficacy to reduce the reservoir of MRSA in the hospital.     

Effects of long-term feeding of marine oils with different positional distribution of eicosapentaenoic and docosahexaenoic acids on lipid metabolism, eicosanoid production, and platelet aggregation in hypercholesterolemic rats

To clarify the clinical features of nosocomial pneumonia during mechanical ventilation (ventilator-associated pneumonia) and to select the appropriate antibiotic therapy for patients, we performed a clinical analysis of 19 patients (26 episodes) with this condition. The following results were obtained. 1, The average age of the patients was 68 years old (male 16, female 3). 2, VAP occurred three times in 2 cases, twice in 3 cases, and once in 14 cases. 3, The duration of mechanical ventilation was from 7 days to 11 years and 5 months (the average was 2.1 years). 4, The microorganism isolated from the aspiration sputum of the VAP patients was Pseudomonas aeruginosa frequently, but it was difficult to determine whether this microorganism was the causative microorganism. Ten strains of Staphylococcus aureus (MRSA seven strains and MSSA three strains) were newly isolated at the same time as VAP and especially in the cases in which these were thought to be causative microrganisms, all the patients died within a short time. 5, Antibiotics were clinically effective for 53.8% of all the VAP patients and carbapenem antibiotics (for example, IPM/CS) were also used for the effective group. 6, Regarding the risk factors for VAP, factors such as the duration of mechanical ventilation, the existence of chronic obstructive pulmonary disease, a hyponutritional state, prior antibiotics, aspiration of gastric contents, histamine-type-2 receptor antagonist, and multiple organ failure showed significant differences and were suspected to be associated with the appearance of VAP.     

A contingency-based approach for assessing policies on aging

The analysis of genomic DNA fragment patterns has revealed as a powerful tool for strain discrimination in Staphylococcus aureus; for use as an epidemiological marker, stability during the course of an outbreak is an essential prerequisite. Genomic DNA fragment patterns (SmaI restriction, pulsed-field electrophoresis) of four different epidemic MRSA strains were compared along with intra- and interhospital and country-wide spread over more than 12 months in Germany. Strain I was isolated from infections in 8 hospitals. In one hospital a subclone arised which differed from the original strain by 4 fragments. Strain II was spread among 4 hospitals, isolates from three of these hospitals exhibited a variability of one to three fragments in the 150-200 kb range. Two hospitals in the Hannover-area were affected by strain III; in 17 isolates of this strain a variability up to three fragments was found in the 170-200 kb range. Strain IV was isolated from 19 cases of infections in 3 hospitals in Berlin. The fragment patterns were completely stable. When S. aureus strains are typed by genomic DNA fragment patterns, a variability in a definite range of molecular masses during the course of an epidemic should be taken into consideration.     

Susceptibility of methicillin-resistant Staphylococcus aureus clinical isolates to various antimicrobial agents. IV. Aminoglycoside-modifying enzyme AAC(6')/APH(2") is responsible for arbekacin-resistance enhanced by bleomycin

Resistance patterns against various antimicrobial agents including beta-lactams, aminoglycosides, tetracyclines, fluoroquinolones, macrolides were examined for 58 strains of methicillin-resistant Staphylococcus aureus (MRSA) isolated at Hiroshima University Hospital from April to November 1992. All the MRSA strains produced type II-coagulase but not beta-lactamase. Regarding aminoglycoside-modifying enzymes, 7 strains (12%) appeared to be producing aminoglycoside 4',4"-adenyltransferase AAD(4',4") encoded by aadD without coproduction of bifunctional aminoglycoside 6'-acetyltransferase/2"-phosphotransferase AAC(6')/APH(2") encoded by aacA-aphD (referred to as tobramycin-resistant type, TOBr). The remaining 51 strains (88%) were phenotypically producers of both enzymes (i.e., mix-resistant type, Mixr). AAD(4',4"), encoded by aadD which was reported to be closely linked with bleomycin (BLM)-resistance determinant, could be seen in 100% MRSA strains and ca. 90% strains expressed AAC(6')/APH(2"). BLM endowed Mixr-type but not TOBr-type MRSA strain with enhanced resistance to arbekacin (ABK) dose-dependently, presumably by modifying the production of AAC(6')/APH(2"). The manifestation of ABK-resistant phenotype by Mixr-type MRSA required the coexistence of BLM. Therefore, ABK must be administered carefully to cure MRSA infection in patients who have been treated with BLM.     

In vitro antibacterial activity of vancomycin in combination with panipenem against carbapenem-resistant MRSA

The synergistic relationship between vancomycin (VCM) and carbapenem (CRB) has been reported in antibacterial activity against CRB-resistant strains of MRSA. The purpose of this study is to investigate the antibacterial activity against CRB-resistant MRSA using VCM, panipenem (PAPM), and a combination of both. 8 strains of CRB-resistant MRSA were used to examine the effects of these antibiotics by the broth microdiluton technique. The effect of pH (pH 6, 7, 8) on MIC of VCM alone was not observed in 7 out of 8 strains; MICs were between 1.0-2.0 micrograms/ml. PAPM alone, however, showed an enhancing tendency in alkaline condition in 6 out of 8 strains. There was no influence of pH on MICs in the combination use of VCM and PAPM, showing additive effect in 1 strain and synergistic in 6 strains. Killing-curves against PAPM-resistant MRSA were examined under the following drug combinations; 1/4 MIC of VCM (0.5 micrograms/ml) plus 1/4 MIC of PAPM (16 micrograms/ml), and 1/4 MIC of VCM plus 1/8 MIC of PAPM (8 micrograms/ml). The former drug combination showed synersistic effect; decrease from 1.05 x 10(5) to 6.45 x 10(4) CFU/ml after 6 hours' incubation and to less than 10 CFU/ml after 24 hours. The latter drug combination showed synergistic activity (2.68 x 10(2) CFU/ml) after 24 hours' incubation, but lost antibacterial activity after 48 hours. In conclusion, PAPM in combination with VCM showed synergistic effects on CRB-resistant MRSA. This combination therapy should be evaluated for the treatment of MRSA infection in patients with renal dysfunction.     

Cloning and characterization of the fmt gene which affects the methicillin resistance level and autolysis in the presence of triton X-100 in methicillin-resistant Staphylococcus aureus

In methicillin-resistant Staphylococcus aureus (MRSA) strains, Triton X-100 reduced the oxacillin resistance level, although the degree of reduction varied from strain to strain. To study the responses of MRSA strains to Triton X-100, we isolated a Tn551 insertion mutant of the COL strain that became more susceptible to oxacillin in the presence of 0.02% Triton X-100. The Tn551 insertion of the mutant was transduced back to the parent strain, other MRSA strains (strains KSA8 and NCTC 10443), and methicillin-susceptible strain RN450. All transductants of MRSA strains had reduced levels of resistance to oxacillin in the presence of 0.02% Triton X-100, while those of RN450 did not. Tn551 mutants of KSA8 and NCTC 10443 also had reduced levels of resistance in the absence of 0.02% Triton X-100. The autolysis rates of the transductants in the presence of 0.02% Triton X-100 were significantly increased. Amino acid analysis of peptidoglycan and testing of heat-inactivated cells for their susceptibilities to several bacteriolytic enzymes showed that there were no significant differences between the parents and the respective Tn551 mutants. The Tn551 insertion site mapped at a location different from the previously identified fem and llm sites. Cloning and sequencing showed that Tn551 had inserted at the C-terminal region of a novel gene designated fmt. The putative Fmt protein showed a hydropathy pattern similar to that of S. aureus penicillin-binding proteins and contained two of the three conserved motifs shared by penicillin-binding proteins and beta-lactamases, suggesting that fmt may be involved in cell wall synthesis.     

Clinical significance of fungal and microbial associations and antibacterial therapy for treatment of chronic inflammatory respiratory tract diseases in children

Microbiological examination applied to 270 children with chronic inflammatory and relapsing respiratory tract diseases revealed that by the frequency of the etiologically significant organisms the main pathogens isolated from the bronchial secretion belonged to Haemophilus influenzae, then followed Streptococcus pneumoniae and the less frequent isolates belonged to Branhamella catarrhalis characterized by high susceptibility to the 2nd and 3rd generation cephalosporins, erythromycin and azithromycin. Mycological investigation of the oral mucus and sputum from the patients revealed high frequency of Candida, mainly C.albicans. The fungi were most frequent and abundant in the children with chronic pulmonary diseases and congenital immune deficiency and in the children with bronchial asthma and asthmatic bronchitis, as well as in the children with exacerbation of the chronic disease, especially with bronchial obstruction. The antibacterial therapy with semisynthetic penicillins, cephalosporins and macrolides led to an increase in the number of the Candida carriers and in the biological material contamination level. The fungal contamination of the host was mainly observed after the use of the penicillins and cephalosporins. Chronic Candida carriers were detected among the patients with chronic inflammatory diseases of the lungs. The diseases in such patients were particularly severe. There were also detected children with colonization resistance to Candida. In the latter cases the chronic process was more favourable. The data made it possible to recommend a more differential use of the antibacterial and antimycotic drugs in the treatment of children with chronic inflammatory diseases of the bronchopulmonary system.     

Extended spectrum beta-lactamases in Danish Klebsiella isolates

This study presents the first two cases of infections with Klebsiella pneumoniae producing extended spectrum betalactamases (ESBL) that have been recorded in Denmark. They presented as a urinary tract infection and a generalized infection in a patient admitted to an intensive care unit. Both patients had been treated with broad spectrum antibiotics prior to infection. Presumably, one of the strains had been imported from Turkey. The ESBL of the two strains were characterized as SHV-2 and SHV-5, respectively. Patients transferred from hospitals abroad should be screened for Klebsiella producing ESBL, in addition to MRSA and other multiresistant organisms. A restrictive antibiotic policy and strict hygienic precautions are essential measures to control the selection and spread of such organisms in the hospital environment.     

耐碳青霉烯鲍曼不动杆菌医院内播散和感染患者预后分析

目的:分析2007年1月至2008年3月北京大学第三医院临床分离的耐碳青霉烯鲍曼不动杆菌的同源性,调查其定植或感染的危险因素,评价该菌所致医疗相关性感染的抗菌药物治疗.方法:通过复习病历收集耐碳青霉烯鲍曼不动杆菌定植或感染患者的临床资料.菌株的药敏试验采用纸片法,通过脉冲场凝胶电泳分析菌株的同源性.结果:研究期间共分离到49株耐碳青霉烯鲍曼不动杆菌菌株,其脉冲场凝胶电泳分型为7型,共45株(91.8%)具有同源性.分离到菌株前患者最常见的暴露因素为住ICU、侵入性操作和低白蛋白血症,最常见的合并症是慢性阻塞性肺疾病(12例)和脑血管病(10例).在这49株菌中,定植者28株,导致感染者21株,感染患者的死亡率为38.1%.Logistic回归分析发现APACHEⅡ评分是导致死亡的独立危险因素(P=0.02,OR=1.7,95%CI1.1～2.5).抗菌药物联合治疗的成功率高于单药治疗(11/13例,84.6%vs.3/17例,17.6%),尤其是头孢哌酮/舒巴坦联合左氧氟沙星联合治疗.结论:我院自2007年出现了耐碳青霉烯鲍曼不动杆菌菌株的院内播散,导致播散的危险因素为住ICU、侵入性操作、低白蛋白血症、慢性阻塞性肺疾病和脑血管病,对耐碳青霉烯鲍曼不动杆菌感染,抗菌药物联合治疗可能优于单药治疗.