Incidence of acute otitis media associated with group A and B respiratory syncytial virus infections

The comparative association of respiratory syncytial virus group A and B infections with acute otitis media was determined by analysing the hospital records of children with community-acquired respiratory syncytial virus infection during three successive outbreaks from 1987 to 1992. Of 326 episodes analysed, 192 (59%) were caused by group A and 134 (41%) by group B infections. Acute otitis media was diagnosed in 101 (75%) children with group B infection, compared with 119 (62%) with group A infection (p = 0.01). Group A infections were more often associated with wheezing (71% versus 59% in group B; p = 0.02) and oxygen therapy in inpatients (48% versus 31%, respectively; p = 0.008). The higher incidence of acute otitis media associated with group B infections was observed both after adjustment for potential confounding variables and during each outbreak.     

Pathogens isolated during treatment failures in otitis

OBJECTIVES: A prospective study in the Paris region to evaluate the clinical and bacteriologic epidemiology of acute otitis media in infants in whom oral antibiotic therapy resulted in clinical failure. METHODS: The study included 186 children with a mean age of 17.5 +/- 13.1 months. Two-thirds of them attended a day-care center and 40.8% had a history of recurrent otitis media. The most frequently prescribed prior antibiotics were amoxicillin-clavulanic acid (43% of cases), an oral third generation cephalosporin (22.6%), erythromycin-sulfisoxazole (11.8%) and a first generation cephalosporin (10.2%). The average duration of antibiotic therapy was 6.9 +/- 2.65 days. Specimens for bacterial cultures included 188 samples of middle ear fluid obtained by tympanocentesis and 37 collected from otorrhea fluid. RESULTS: One hundred forty-one samples (62.7%) from 126 children yielded 170 bacterial isolates. In 60 children (32.3%) the culture of the ear pus was sterile. Among the 170 bacterial isolates: 67 (39.4%) were Streptococcus pneumoniae (59 patients), of which 77.6% had reduced susceptibility to penicillin (PRSP with penicillin MIC > or = 0.125 mg/l); 61 (35.9%) were Haemophilus influenzae (56 patients) of which 49.2% were beta-lactamase producers; and 8 were Moraxella catarrhalis (8 patients), of which 87.5% were beta-lactamase producers. Thirty-six patients were infected by S. pneumoniae with penicillin MIC > or =1 mg/l. In our study attending day-care center (P = 0.04), temperature >38 degrees C with signs of otalgia (P = 0.02), age <2 years (P = 0.048) and prior antibiotic treatment with erythromycin-sulfisoxazole (P = 0.006) were independently predictive risk factors for patients infected with penicillin-resistant S. pneumoniae. Pneumococcal serogroups 23, 14 and 19 were predominant (25.4, 25.4 and 23.8%, respectively). Penicillin resistance was mainly associated with serogroups 23 and 14. CONCLUSIONS: Penicillin-resistant S. pneumoniae isolates are frequently responsible for therapeutic failure in cases of acute otitis media in the Paris region.     

Clinician-educators in academic medical centers: a two-part challenge

Between 1967 and 1996, > 18,700 strains of Yersinia species, excluding Yersinia pestis, were recovered in Belgium from a variety of gastrointestinal and extraintestinal sites in patients. Full identification and serotyping were performed by the two Belgian reference laboratories. Yersinia enterocolitica serogroup O:3 predominated (79.4% of strains), followed by serogroup O:9 (11.1%). The remaining 9.5% of isolates belonged to serogroups and related species generally considered nonpathogenic. Acute enterocolitis was the most common clinical form of Y. enterocolitica infection, affecting primarily children younger than 5 years of age. Since 1967, there was a steady increase in isolations every year, with 305 cases in 1975 and up to 1,469 in 1986. From 1987 on, there was a clear decrease in the number of reported cases, although the number of participating laboratories and culture techniques remained constant. This significant decrease in the occurrence of Y. enterocolitica infections may be explained by changes in the slaughtering procedures and eating habits of the population.     

Something's rotten: a nosocomial outbreak of malodorous Pseudomonas aeruginosa

From July 1994 through November 1996, a phenotypically unique strain of Pseudomonas aeruginosa producing a pungent, "rotten-potato" odor and a positive lysine decarboxylase reaction was isolated from 39 patients at UCLA Medical Center (Los Angeles). Most cases (95%) were in intensive care units and had clinical infections (72%). Most isolates (74%) were recovered from cultures of respiratory secretions. To determine risk factors for acquisition of the organism, 23 cases were compared with 23 randomly selected controls matched by service and isolate date. Multivariate analysis revealed that isolation of malodorous P. aeruginosa was associated with mechanical ventilation of > 24 hours' duration (odds ratio [OR] = 9.4; P = .001) and transfer from an outside hospital (OR = 5.7; P = .04). DNA from outbreak strains hybridized to P. aeruginosa-specific toxin A and phospholipase C gene probes and all outbreak isolates tested were found to be identical by use of pulsed-field gel electrophoresis. An unusual phenotypic characteristic of the strain led to the recognition of a nosocomial outbreak of P. aeruginosa infection associated with mechanical ventilation.     

Antimicrobial activity of ofloxacin against recent clinical isolates from otitis media and otitis externa]

In order to evaluate the annual changes of susceptibility, minimum inhibitory concentrations (MICs) of ofloxacin (OFLX) and 4 control drugs were determined against clinical isolates that were obtained from patients with otitis media and otitis externa during the periods between January and December 1993, and the periods between October 1996 and March 1997. The results are summarized as follows: 1. No annual changes were seen for MIC50 of OFLX, but MIC80 and MIC90 of that rose against methicillin-resistant Staphylococcus aureus (MRSA), coagulase-negative staphylococci (CNS) and Pseudomonas aeruginosa from 1993 to 1996. It appears that resistance to OFLX is increasing among these bacteria. Detection frequency of highly resistant strains to OFLX (MIC > 100 micrograms/ml) was lower than to other control drugs. 2. No annual changes were seen of MIC50, MIC80 and MIC90 of OFLX against methicillin-susceptible S. aureus (MSSA), Streptococcus spp., Proteus spp. and Haemophilus influenzae. OFLX showed strong antimicrobial activities against these bacteria. 3. Since there was no large annual changes in the antimicrobial activity of OFLX against clinical isolates that were obtained from patients with otitis media and otitis externa, OFLX otic solution was considered as one of the clinically useful drugs even now.     

Identification of infectious Pseudomonas aeruginosa strains in an occupational saturation diving environment

OBJECTIVES: Occupational saturation divers have various skin disorders, of which skin infections are the most serious and frequent. Pseudomonas aeruginosa is the microbe most often isolated from skin infections in divers. The purpose of the present work was (a) to report the occurrence of P aeruginosa in skin infections in operational saturation diving in the North Sea from 1987 to 1995; (b) to report the environmental occurrence of P aeruginosa in saturation diving systems, and finally (c) to identify possible relations between infection related to strains of P aeruginosa and environmental isolates of the microbe. RESULTS: During the period 1987-95, P aeruginosa was isolated from 257 skin infections in operational saturation divers. Most of the isolates related to infection by P aeruginosa show a unique growth inhibition pattern towards the normal skin flora, and the serotype pattern of P aeruginosa from skin infections is limited compared with similar infections in non-divers. In a mini-epidemiological study on board one diving vessel during one operational diving period, five significantly different DNA fragment profiles were found among the 12 isolates related to infection by P aeruginosa obtained from the saturation system. In two cases the infectious genotypes were detected in the fresh water for the saturation chambers weeks before the arrival of the infected diver. CONCLUSIONS: The most commonly used epidemiological marker for P aeruginosa world wide, also used in earlier studies, is serotyping, but with pulsed field gel electrophoresis (PFGE) miniepidemiology it was shown to be insufficient for epidemiological purposes in saturation environments. PFGE analyses were shown to be superior both to antibacterial factor and to serotyping in epidemiological analyses of P aeruginosa infections in saturation diving.     

Penicillium marneffei fungemia in an AIDS patient: the first case report in Taiwan

The microbiology of in 55 ear aspirates obtained from 34 children with chronic otorrhea was studied. Aspiration of the middle ear exudate was done immediately following removal of tympanostomy tube (TT). The middle ear aspirates and swab specimens of the external auditory canals were cultured for aerobic and anaerobic bacteria. Sixty-five isolates were recovered only from the middle ears, 73 only from the external ear canals, and 73 were present at both sites. Analysis of the 138 middle ear isolates demonstrated the recovery of aerobic bacteria only in 28 patients (50%), anaerobes only in seven (13%), and both aerobes and anaerobes in 20 (36%). There were 77 aerobic and 61 anaerobic isolates. Commonly recovered aerobes were Pseudomonas aeruginosa (17 isolates), Staphylococcus aureus (11), Proteus sp. (7), Moraxella catarrhalis (6), Klebsiella pneumoniae (5) and non-typable Haemophilus influenzae (5). Commonly isolated anaerobes were Peptostreptococcus sp. (25 isolates), Prevotella sp. (10), Bacteroides sp. (8) and Fusobacterium sp. (6). Pseudomonas aeruginosa and S. aureus were more often isolated in children older then 6 years. These findings demonstrate the polymicrobial bacteriology of TT-related otorrhea in children. Specimens collected from the external auditory canals can be misleading. Reliable information can be obtained from the ear exudes when collected through the TT or through the open perforation after their removal.     

Computer simulation of a neurosurgical operation: craniotomy for hypothalamic hamartoma

OBJECTIVE: Analysis of the spectrum of diseases attributed to Pseudomonas aeruginosa in patients with coinfection with the immunodeficiency virus (HIV). METHODS: Retrospective study of 35 cases of coinfection with P. aeruginosa-HIV, attended from 1985 until 1995. Analysis of putative factors implicated in mortality secondary to P. aeruginosa infection. RESULTS: The spectrum of infection due to P. aeruginosa was: ORL infection (4 cases), infection of upper respiratory tract (4 cases), pneumonia (21 cases), infected bronchiectasias (one case), endocarditis (2 cases) and primary bacteremia (3 cases). Most of these infections were community-acquired ones (30 cases [85.7%]). Degree of immunodepression was variable, with 12 cases (34.3%) affecting to patients with more than 200 CD4+lymphocytes x 10(-9)/l. Radiological pattern of pneumonias consisted in alveolar consolidation (18 cases [85.7%]), necrotizing pneumonia (2 cases [9.5%]) and interstitial pattern (one case [4.8%]). More than a 80% of isolates of P. aeruginosa was sensible to ceftazidime, ciprofloxacin, aminoglycosides, ureidopenicillins and imipenem. Recidives of the P. aeruginosa infection were detected in 7 cases (20%): 4 cases of ORL infection (100%) and 3 cases of lower respiratory tract infection (13.6%). Overall mortality was a 20% (7 cases), being directly attributed to P. aeruginosa infection in every one of the cases, all of them pneumonias. Secondary bacteremia was associated to a higher mortality (odds ratio [OR] 18.67; p = 0.0207). CONCLUSIONS: P. aeruginosa affect to the HIV-infected patients, independently of their immunodepression degree, affecting to different localizations. This bacteria continues to be sensible to conventional anti-Pseudmonas treatment. Pneumonia with secondary bacteremia is associated to a higher mortality.     

Streptococcus pneumoniae blood culture isolates from patients with and without human immunodeficiency virus infection: alterations in penicillin susceptibilities and in serogroups or serotypes

We performed a 3-year retrospective study of Streptococcus pneumoniae blood culture isolates recovered at Baragwanath Hospital, Soweto, South Africa, from 1993 to 1995. The study group comprised 457 patients, including 98 children, of known human immunodeficiency virus (HIV) serostatus. Of these patients, 70 (30 [8.4%] of 359 adults and 40 [40.8%] of the 98 children) were infected with penicillin-resistant S. pneumoniae strains (minimal inhibitory concentration, > or = 0.12 microg/mL); 56 of these strains were intermediately resistant to penicillin. HIV-positive patients had significantly more penicillin-resistant isolates than did HIV-negative patients (43 [29.7%] of 145 HIV-positive patients vs. 27 [8.6%] of 312 HIV-negative patients; P < .001); this difference was found for both adults (19% vs. 4.3%; P < .001) and children (53.3% vs. 30.2%; P < .0343). Multiple resistance occurred more frequently in HIV-positive children (P = .02). HIV-positive adults had a statistically significant increase in the percentage of serogroups and serotype usually found in children and commonly associated with antimicrobial resistance, i.e., serotype 14 and serogroups 6, 19, and 23 (48% vs. 28.6%; P < .001). The increased prevalence of serogroups or serotypes usually found in children was also found among penicillin-susceptible strains. These data suggest that HIV-infected adults may again become susceptible to the serogroups or serotypes found in children.     

Identifying adverse events caused by medical care: degree of physician agreement in a retrospective chart review

Forty critically ill adult patients with severe Gram-negative infection were treated with once-daily amikacin combined with ceftazidime. The mean age was 56.6 +/- 19 years and mean APACHE II score was 22.7 +/- 6.6. Forty percent of patients required mechanical ventilation. The mean creatinine clearance at onset of therapy was 59.4 +/- 28 ml/min. All bacterial isolates were sensitive to amikacin. Fixed doses of amikacin 15 mg/kg, 12 mg/kg, and 8 mg/kg body weight were given once daily to patients with estimated creatinine clearance of > 80 ml/min., 50-80 ml/min., and < 50 ml/min, respectively. Forty-two causative gram-negative bacteria were isolated from 40 patients. The most common bacteria were Pseudomonas aeruginosa (18), and Escherichia coli (10). Overall clinical success and bacteriological eradication occurred in 85% and 87.5% of patients; 78.9% and 79% of patients with hospital-acquired infections; 90.5% and 95.2% of patients with community-acquired infections; and 62.5% and 81.3% of patients requiring mechanical ventilation, respectively. Therapeutic failure was documented in 15% of patients. Death due to infection was scored in two patients. The remaining were all due to persistence of the initial causative bacteria in patients with hospital-acquired infections. Persistence was documented with Ps. aeruginosa (2), Serratia spp. (1), and Acinetobacter spp. (1). Overall mortality occurred in 22.5% patients. Death unrelated to infection occurred in 7 patients. There was no clinical evidence of ototoxicity in any of our patients, however, nephrotoxicity was documented in 5%. In conclusion, once-daily amikacin combined with ceftazidime is practical, efficacious and probably safe in critically ill infected patients.     

Rapid detection and evaluation of clinical characteristics of emerging multiple-drug-resistant gram-negative rods carrying the metallo-beta-lactamase gene blaIMP

Gram-negative rods (GNR) carrying the transferable carbapenem resistance gene blaIMP, including Pseudomonas aeruginosa and Serratia marcescens, have been isolated from more than 20 hospitals in Japan. Although the emergence of such multiple-drug-resistant bacteria is of utmost clinical concern, little information in regard to the distribution of blaIMP-positive GNR in hospitals and the clinical characteristics of infected patients is available. To address this, a system for the rapid detection of the blaIMP gene with a simple DNA preparation and by enzymatic detection of PCR products was developed. A total of 933 ceftazidime-resistant strains of GNR isolated between 1991 and 1996 at Nagasaki University Hospital, Nagasaki, Japan, were screened for the blaIMP gene; 80 isolates were positive, including 53 P. aeruginosa isolates, 13 other glucose-nonfermenting bacteria, 13 S. marcescens isolates, and 1 Citrobacter freundii isolate. Most of the patients from whom blaIMP-positive organisms were isolated had malignant diseases (53. 8%). The organisms caused urinary tract infections, pneumonia, or other infections in 46.3% of the patients, while they were just colonizing the other patients evaluated. It was possible that blaIMP-positive P. aeruginosa strains contributed to the death of four patients, while the other infections caused by GNR carrying blaIMP were not lethal. DNA fingerprinting analysis by pulsed-field gel electrophoresis suggested the cross transmission of strains within the hospital. The isolates were ceftazidime resistant and were frequently resistant to other antibiotics. Although no particular means of pathogenesis of blaIMP-positive GNR is evident at present, the rapid detection of such strains is necessary to help with infection control practices for the prevention of their dissemination and the transmission of the resistance gene to other pathogenic bacteria.     

Imipenem resistance in Pseudomonas aeruginosa

In 1997 in western Austria, 9.9% of Pseudomonas aeruginosa strains from patients of general practitioners were resistant to imipenem as well as 18.2% of the isolates from hospitals and 20.2% of the strains at a university teaching hospital. Within the hospital the imipenem resistance varied from 9.9% among out-patients to 28.7% in isolates from intensive care units. In medical/surgical words, up to 15.1% of P. aeruginosa strains were resistant to imipenem. The incidence of imipenem-resistant P. aeruginosa strains correlates to the use of carbapenems. In June 1997, 10 consecutive isolates from 8 patients were obtained and typed using restriction fragment length polymorphism analysis (RFLP) and Pyocin typing. All 10 isolates were resistant to meropenem as well as to imipenem. The finding (by RFLP and Pyocin typing) of individual bacterial types in each isolate strongly contradicts the spread of infection by cross infection. However, all patients were proven to have been treated with imipenem during the 3 months prior to testing. In 1997, 13,880 g of imipenem were used at the university hospital in Innsbruck. The use of carbapenems appears to be the main cause for the increased incidence of imipenem-resistant P. aeruginosa strains.     

Complex serology and immune response of mice to variant high-molecular-weight O polysaccharides isolated from Pseudomonas aeruginosa serogroup O2 strains

The O antigen of the Pseudomonas aeruginosa lipopolysaccharide is the optimal target for protective antibodies, but the unusual and complex nature of their sugar substituents has made it difficult to define the range of these structures needed in an effective vaccine. Most clinical isolates of P. aeruginosa can be classified into 10 O-antigen serogroups, but slight chemical differences among O polysaccharides within a serogroup give rise to subtype epitopes. These epitopes could impact the reactivity of O-antigen-specific antibodies, as well as the susceptibility of a target strain to protective, opsonic antibodies. To define parameters of serogroup and subtype-epitope immunogenicity, antigenicity, and surface expression on P. aeruginosa cells, we prepared high-molecular-weight O-polysaccharide vaccines from strains of P. aeruginosa serogroup O2, for which eight structurally variant O antigens expressing six defined subtype epitopes (O2a to O2f) have been identified. A complex pattern of immune responses to these antigens was observed following vaccination of mice. The high-molecular-weight O polysaccharides were generally more immunogenic at low doses (1 and 10 microg) than at a high dose (50 microg) and usually elicited antibodies that opsonized the homologous strain for phagocytic killing. Some of the individual polysaccharides elicited cross-opsonic antibodies to a variable number of strains that express all of the defined serogroup O2 subtype epitopes. Combination into one vaccine of two antigens that individually elicited cross-reactive opsonic antibodies to most members of the O2 serogroup inhibited, instead of enhanced, the production of antibodies broadly reactive with most serogroup O2 subtype strains. Thus, immune responses to P. aeruginosa O antigens may be restricted to a limited range of epitopes on structurally complex O antigens, and combining multiple related antigens into a single vaccine formulation may inhibit the production of those antibodies best able to protect against most P. aeruginosa strains within a given O-antigen serogroup.     

Molecular epidemiology provides evidence of genotypic heterogeneity of multidrug-resistant Pseudomonas aeruginosa serotype O:12 outbreak isolates from a pediatric hospital

Ribotyping randomly amplified polymorphic DNA analysis, and pulsed-field gel electrophoresis were used for the epidemiologic evaluation of eight Pseudomonas aeruginosa O:12 isolates obtained from eight children and two P. aeruginosa O:12 environmental isolates from a hematology ward. Randomly amplified polymorphic DNA analysis and pulsed-field gel electrophoresis were able to discriminate isolates that were indistinguishable by biochemical typing, O serotyping or ribotyping.     

Synthesis of novel cyclic protease inhibitors using Grubbs olefin metathesis

The microbiologic features of infected sinus aspirates in nine children with neurologic impairment were studied. Anaerobic bacteria, always mixed with aerobic and facultative bacteria, were isolated in 6 (67%) aspirates and aerobic bacteria only in 3 (33%). There were 24 bacterial isolates, 12 aerobic or facultative and 12 anaerobic. The predominant aerobic isolates were Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus (2 each) and Proteus mirabilis, Pseudomonas aeruginosa, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae (1 each). The predominant anaerobes were Prevotella sp. (5), Peptostreptococcus sp. (4), Fusobacterium nucleatum (2), and Bacteroides fragilis (1). Beta-lactamase-producing bacteria were isolated from 8 (89%) patients. Organisms similar to those recovered from the sinuses were also isolated from tracheostomy site and gastrostomy wound aspirates in five of seven instances. This study demonstrates the uniqueness of the microbiologic features of sinusitis in neurologically impaired children, in which, in addition to the organisms known to cause infection in children without neurologic impairment, facultative and anaerobic gram-negative organisms that can colonize other body sites are predominant.     

Complementation of methionine auxotrophs of Pseudomonas aeruginosa from cystic fibrosis

Auxotrophic Pseudomonas aeruginosa are exclusive to respiratory infections in cystic fibrosis (CF) and bronchiectatic patients, and isolates require specific amino acids for growth on minimal media, particularly methionine. Since auxotrophic and prototrophic P. aeruginosa from CF are identical by genotyping, we investigated the genetic events leading to methionine auxotrophy (Met-). Most (10/13) Met- strains had the same pattern of growth on methionine precursors and required methionine exclusively for growth. Back mutation to prototrophy was very low (frequencies 10(-8) to <10(-10)). Complementation of the mutations leading to auxotrophy was achieved for five strains with a genomic library of P. aeruginosa PAO1. Strains with different patterns of growth on methionine precursors were complemented by clones with different restriction patterns, while identical clones complemented strains with the same pattern of growth on methionine precursors. Methionine auxotrophy in P. aeruginosa from CF results from stable chromosomal mutations, and the commonest defect is probably in gene(s) encoding enzymes that convert homocysteine to methionine.     

Evaluation of cefaclor in acute otitis media caused by ampicillin-resistant H. influenzae

Cefaclor was used to treat 13 children with acute otitis media caused by ampicillin-resistant strains of Hemophilus influenzae. The children were re-examined on days 4, 10, and 28. Pharmacologic compliance was assessed by means of a bioinhibition assay on a urine specimen obtained on days 4, 7, and 10. Nine of the 13 children had evidence by tympanogram of residual otitis media with effusion (secretory otitis media). Of these, three were noted to have a bulging, yellow or grey eardrum, which suggested an ongoing acute process. A second middle ear culture was obtained from two of the 3 children, but no pathogens were recovered. Two others had recurrence of otitis shortly after cessation of therapy. Cefaclor is an acceptable antibiotic for the treatment of ampicillin-resistant acute otitis media; but, after cefaclor therapy, some children continued to have a bulging eardrum and sterile pus in the middle ear or had recurrences of otitis soon after cessation of therapy.     

Molecular epidemiology of a parainfluenza type 3 virus outbreak on a pediatric ward

Parainfluenza type 3 virus (PIV-3), an important cause of acute lower respiratory illness in children, can be transmitted nosocomially. To differentiate between nosocomial transmission and community-acquired infection, a polymerase chain reaction-based sequencing assay was developed for the 5' noncoding region of the PIV-3 fusion protein gene and was applied to virus specimens from 10 children infected with PIV-3 during a hospital outbreak. Four strains of PIV-3 were identified among the 10 virus isolates. Six isolates, which appeared to belong to 1 strain, were obtained from a cluster of nosocomial cases in a pediatric intermediate care unit. In contrast, the remaining 4 isolates, which appeared to belong to 3 different strains, were obtained from children infected in the community or elsewhere in the hospital. These data indicate that multiple strains of PIV-3 can be found during a single epidemic and provide evidence that infections within the intermediate care unit were probably caused by transmission of 1 strain of virus within the unit rather than reintroduction of virus by new patients or staff.     

Analysis of genome-type, serovar and antibiotic susceptibility of Pseudomonas aeruginosa isolated in Beijing Hospital China in 1991 to 1993]

We analyzed the in vitro antibiotic susceptibility pattern and serovar for 192 strains of Pseudomonas aeruginosa isolated at Beijing Hospital(China) from October 1991 to October 1993. The frequency of resistant strains was high, more than 15%, for ceftazidime, cefsulodin, cefoperazone, aztreonam, gentamicin, tobramycin, tosufloxacin, ofloxacin and fosfomycin. The incidence of resistants against piperacillin and imipenem was significantly low. Among the 192 strains, 16 were designated as being multi-drug resistant strains(i.e.; resistant to more than 8 drugs out of 11 drugs), and all of the multi-drug resistant strains were isolated from inpatients. Predominant serovar of 192 strains were 60(31.3%) for G, 28(14.7%) for E, and 24(12.5%) for I. Multi-drug resistant strains have no characteristic serovar. Restriction enzyme SpeI digestion analysis(using pulse field electrophoresis) of P. aeruginosa-genome yielded several common patterns, and was shown to be useful for tracing the route of nosocomial infection. Further, isolates with closely related genome type, in which the size of one digested band was different, showed a different minimum inhibitory concentration of fosfomycin in one genome type or new quinolones in the other genome type. Analysis of genome type and antibiotic susceptibility pattern may exhibit the antibiotic resistant gene.     

Change of pathogeus and pathogen persistence in chronic urinary tract infections in childhood. E. coli-O-serotypes in follow-up

In 171 children with urinary tract infections, all strains of E. coli O isolated from the urine in the course of two years were serotyped. The serogroups 06, 02, 08 and 01 were predominant. Follow-up examinations revealed a 78% incidence of reinfection, while relapses (= identical E. coli serotypes or pathogen species) only occurred in 22% of all new episodes. Two thirds of all reinfections by E. coli occurred within two months of the previous E. coli infection.