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PubMed1975

Motility-indole-lysine medium for presumptive identification of enteric pathogens of Enterobacteriaceae.

Detection of lysine decarboxylase activity is a useful supplement to reactions on triple sugar-iron (TSI) and urea agars in the initial examination of suspected pathogenic isolates from fecal cultures. Owing to the added value of motility and indole production in the differentiation of enteric pathogens, we prepared and evaluated a motility-indole-lysine (MIL) medium. The following 890 organisms were tested: 264 Shigella, 2 Edwardsiella, 182 Salmonella enteritidis, 235 S. typhi, 3 Arizona, 32 Yersinia enterocolitica, and 172 other members of the family Enterobacteriaceae. With few exceptions the MIL medium gave the same results as the standard motility, indole, and lysine decarboxylase (Moeller) test media. All discrepancies were with the indole reaction, which was weak in 2 of 67 strains of Escherichia coli and falsely negative in 6 of 32 strains of Y. enterocolitica. When both TSI agar and lysine-iron agar (LIA) slants are used in the evaluation isolates from fecal cultures, detection of H2S is duplicated. Both LIA and MIL medium detect lysine decarboxylase and deaminase activity equally well. Because of its ability to detect motility and indole production, the MIL medium is more useful than LIA when used with TSI agar. The combination of TSI agar, MIL medium, and urea agar enables reliable initial recognition of enteric pathogens of the Enterobacteriaceae.

Carboxy-Lyases↗
PubMedDate not supplied

Aggregative Escherichia coli, Salmonella, and Shigella are associated with increasing duration of diarrhea.

In order to relate etiology of diarrhea to the duration of the episode, a cohort of 452 children up to 36 months of age was visited once weekly at their households for 18 consecutive months to record diarrheal morbidity. Fecal specimens were obtained in 453 diarrheal episodes occurring in 354 children during this period. The common putative agents as single isolations associated with diarrhea were EA-AggEC (17.2%), ETEC (14.1%), EPEC (6.0%) and rotavirus (4.0%). The pathogens with higher median duration of diarrhea were Shigella (13.5; mean +/- SD 13.7 +/- 2.7), Salmonella (8.8: 15.3 +/- 4.5) and EA = AggEC (12.0: 15.1 +/- 1.8). Of 55 episodes with duration of greater than 14 days, the main pathogens isolated were EA-AggEC (32.7%), ETEC (9.0), Salmonella, G. lamblia (5.5% each) and Shigella (3.5%). These data provide a preliminary evidence to suggest that EA = AggEC may well be the main long sought microbial agent responsible for diarrhea of long duration.

Child, Preschool↗
PubMed1992

Medical treatment of chronic suppurative otitis media without cholesteatoma in children--a two-year follow-up.

A prospective long-term study was carried out in 48 infants and children with chronic suppurative otitis media without cholesteatoma treated initially with wide spectrum intravenous antibiotics and suction and debridement. Patients were followed for a period of two years. All children were cured after completion of therapy. At 3 and 6 months follow-up 75% of the children were still free of discharge and at 12, 18 and 24 months the proportion of dry ears dropped to 71%, 66% and 52%, respectively. Eighty percent of all recurrences developed already during the first 6 months of follow-up. Pseudomonas aeruginosa was the most common pathogen isolated, both in the initial and recurrent bouts of the disease, and was commonly associated with other pathogens. Children with early reappearance of ear discharge were less likely to benefit from further antimicrobial or surgical treatment. The recurrence rate was not affected by the antibiotic regimen, age, duration of drainage before treatment or the presence of granulation tissue. No intracranial or intratemporal complications were observed during the follow-up period.

Ceftazidime↗
PubMed2006

Bacteremia in adult patients with acquired immunodeficiency syndrome in the northeast of Thailand.

BACKGROUND: Bacteremia is a frequent complication found in HIV-infected patients and is usually associated with a poor prognosis. This study was undertaken to describe the bacterial pathogens causing bacteremia in adult Thai HIV-infected patients, and hence to give guidance in the choice of empirical antimicrobials. METHODS: Blood culture results at Srinagarind Hospital, Khon Kaen during the period January 1996 to December 2001 were retrospectively reviewed. RESULTS: In HIV-infected and HIV-uninfected patients, 172 and 4082 episodes of bacteremia occurred, respectively. In HIV-infected patients, community-acquired and nosocomial bacteremia were found in 78.5% and 21.5%, respectively and most were monomicrobial. Gram-negative bacteria were the main pathogens isolated in both groups of bacteremia. Escherichia coli and methicillin-resistant Staphylococcus aureus were more common pathogens causing nosocomial bacteremia in HIV-infected patients, whereas Acinetobacter spp were more common in HIV-uninfected patients. Salmonella spp, especially Salmonella groups D and B, were the most common (62.2%) pathogen in community-acquired bacteremia in HIV-infected patients whereas Escherichia coli was the most common in HIV-uninfected patients. Only a few episodes of community-acquired bacteremia in HIV-infected patients had identified sources. Co-trimoxazole resistance was common in community-acquired bacteremia caused by Gram-negative bacilli in HIV-infected patients, with Salmonella group B being more resistant to co-trimoxazole than Salmonella group D (statistically significant, p<0.001). However, resistance rates to ceftriaxone and ofloxacin were low. CONCLUSIONS: Bacteremia in adult HIV-infected patients was usually caused by Gram-negative bacilli in both community-acquired and nosocomial settings. Salmonella spp was the most common organism identified, especially Salmonella group B and D. Ceftriaxone or fluoroquinolones such as ofloxacin or ciprofloxacin should be used as the initial empiric therapy for HIV-infected patients with suspected bacteremia.

Acquired Immunodeficiency Syndrome↗
PubMed1975

Virologic and serologic studies of zoo birds for Marek's disease virus infection.

One hundred and eleven zoo birds representing 49 species in 14 orders were examined for Marek's disease (MD) herpesvirus (MDHV) infection. MDHV was isolated from 10 birds, all belonging to genus Gallus. The precipitating antibodies against MDHV were demonstrated only in the Gallus birds, when 51 selected birds including 34 Galliformes and 17 other birds representing 12 species from nine orders were examined. The 10 MDHV isolates all induced morphologically similar plaques in cell cultures closely resembling those of HN strain, a low pathogenic isolate of MDHV. Six of the 10 isolates, when inoculated into an experimental line of chickens highly susceptible to MD, caused only a minimal degree of histologic lesions without causing clinical MD, gross MD lesions, or deaths from MD. Natural hosts of MD are probably Galliformes, primarily affecting Gallus and less often other genera of Galliformes.

Animals↗
PubMed2003

[Microorganisms isolated from clinical specimens of patients from the Department of Thoracic Surgery].

The clinical specimens received from patients hospitalized in Department of Thoracic Surgery between 1997 and 2001 were microbiologically examined. The main specimen for microbiological examination was pleural fluid (median 34%). The frequency of specimens from bronchial tree increased significantly (from 4% to 26%) with concurrent decrease of sputum (from 29% to 6%). Among isolated pathogens, Gram negative rods were the most frequent (median 48%) and Pseudomonas sp. was the main pathogen among them. Occurrence of staphylococci was median 22% and Staphylococcus aureus, with a little decrease in analyzed period, was still the main Gram positive pathogen. Simultaneously the occurrence of MRSA in the last three years dropped three times. The number of isolations of yeasts have risen from 5.8% to 10.3%.

Bacteriocins↗
PubMed2006

Emerging resistance to carbapenems in a tertiary care hospital in north India.

BACKGROUND AND OBJECTIVES: Carbapenems are beta-lactam antibiotics, presently considered as most potent agents for treating multi-drug resistant Gram-negative bacilli infections. In India carbapenems available for use are meropenem and imipenem, introduced recently. Resistance to these has been reported in a few bacteria especially Pseudomonas spp. We therefore retrospectively evaluated the antibiotic susceptibility pattern to these agents amongst various clinical isolates in a tertiary care hospital in north India. METHODS: In this study Gram-negative bacterial pathogens isolated from clinical samples were tested for extended spectrum beta lactamase (ESBL) production. All ESBL positive bacteria were tested for meropenem and imipenem activity pattern using NCCLS guidelines. A total of 2626 consecutively isolated Gram-negative bacteria, which tested positive for ESBL production by the double disk diffusion method, were included. RESULTS: The different bacteria isolated were Pseudomonas spp. 759, Acinetobacter spp. 676, Escherichia coli 569, Klebsiella spp. 343, Enterobacter spp. 150, Citrobacter spp. 57 and Proteus spp. 72. Overall resistance to meropenem was more (22.16%) than imipenem (17.32%). Maximum resistance was seen in Pseudomonas spp. M(R) 37.6 per cent, I(R) 30 per cent. In isolates from intensive care units (ICU) resistance to carbapenems was significantly higher than non-ICU patients. INTERPRETATION AND CONCLUSION: Resistance to meropenem and imipenem was seen in various clinical isolates of Gram-negative ESBL-positive bacteria. There is a need to alarm our clinicians for judicious use of antibiotics.

Anti-Bacterial Agents↗
PubMed1989

[Infection 1979 to 1986. Epidemiology, etiology, clinical aspects and prognosis in 691 patients].

691 patients with clinically and bacteriologically established sepsis were included in three prospective studies conducted at a university hospital with 1,300 beds in 1979, 1982 and 1986. Only 22.4% of the patients did not suffer from severe underlying diseases. There was a fairly even distribution of gram-positive and gram-negative organisms among the isolated pathogens. A marked increase was seen in the incidence of polymicrobic and mycotic infections. The most frequently isolated bacterial species were E. coli (24.9%), Staph. aureus (19.5%), Staph. epidermidis (8%), Enterococci (4.8%) and Klebsiellae (4.6%). 26.8% of the patients died. The mortality rate showed a marked decrease from 33.6% in 1979 to 22.4% in 1986.

Adult↗
PubMed2026

Patterns of antimicrobial resistance genes in pathogens across One Health sectors in Ireland: an in silico approach.

As part of a rapid risk assessment, an in silico approach was used to detect antimicrobial resistance (AMR) in pathogenic isolates from humans, animals, and the environment. A total of 11,670 genomic data sets were retrieved from the NCBI Pathogen Detection system for Ireland, which represented 47 pathogenic species, including Salmonella enterica, Escherichia coli/Shigella spp., Staphylococcus aureus, Klebsiella pneumoniae, and Enterococcus faecium. Identifying the most critical pathogenic strains over time is essential, as these organisms significantly contribute to mortality, morbidity, and hospitalization. The analysis identified 799 antimicrobial resistance genes (ARGs), including their allelic diversity, 117 plasmid replicons, and 274 virulence factors. Several critical ARGs, particularly those conferring resistance to beta-lactams, aminoglycosides, quinolones, and colistin, were common across isolates originating from human, animal, and environmental sources, suggesting shared resistance profiles across One Health sectors. Klebsiella pneumoniae, E. coli/Shigella spp., S. enterica, and S. aureus were the dominant hosts of these ARGs and associated mobile genetic elements. Increasing resistance across major antibiotic classes aligned with trends reported across other European countries. This study provides a national-scale in silico comparison of AMR across pathogens and One Health sectors using publicly available genomic data. The findings help reinforce Ireland's AMR surveillance by showing which resistance genes are present and how they spread across critical pathogens in humans, animals, and the environment. These findings highlight the urgent need for improved antibiotic stewardship and integrated One Health surveillance to limit the emergence and spread of AMR.IMPORTANCEAntimicrobial resistance (AMR) is a growing threat to human, animal, and environmental health. This study used publicly available genomic data to identify antimicrobial resistance genes (ARGs) in key bacterial pathogens circulating in Ireland. By analyzing over 11,000 genomes from humans, animals, and the environment, we found that several dangerous resistance genes, including those against last-resort antibiotics, were widespread across different sources. The study highlights which bacteria and resistance genes are most critical and how they may spread between humans, animals, and the environment. These insights provide a national snapshot of AMR, supporting more effective monitoring and prevention strategies. By revealing patterns of resistance and modes of transmission, our findings underscore the importance of coordinated antibiotic stewardship and One Health approaches to slow the emergence and spread of resistant infections, protecting public health and ensuring antibiotics remain effective.

Humans↗
PubMed1983

[Comparison of sensitivity patterns of bacteria isolated from clinical materials to the 2d generation cephamycins and cephalosporins and clinical application of these antibiotics].

In vitro susceptibilities of 1478 strains of various pathogens isolated from clinical materials in 1981 to 23 antibiotics were studied using Showa disk diffusion test. Prevalence of bacterial resistance to antibiotics was evaluated. New cephem antibiotics such as cefmetazole (CMZ), cefoxitin (CFX) and cefotiam (CTM) had no increased activity over old cephalosporins such as cephalothin (CET) and cefazolin (CEZ) against Gram-positive cocci. However, all the new ones showed greater activities, broadened spectra, and/or both against Gram-negative bacilli, each offering unique advantages. S. aureus: Susceptible strains (MICs less than 15 micrograms/ml) to CET, CEZ, CTM, CFX and CMZ were 95%, 69%, 92%, 88% and 99%, respectively. Prevalence of resistance to CEZ was greater than to other cephalosporins, showing bimodal distribution of MICs. This may be due to more use of this drug in the past. Sensitive strains to benzylpenicillin (PCG), ampicillin (ABPC), sulbenicillin (SBPC) and piperacillin (PIPC) were 22 to 63%. A striking bimodal distribution of MICs of these penicillins was characteristic. Sensitive strains to various aminoglycosides and tetracyclines were 52 approximately 93% and 97 approximately 100%, respectively. S. pyogenes: 83 approximately 100% of strains were susceptible to various penicillins, CET and CEZ, whereas susceptible strains to CTM, CFX and CMZ were 66 approximately 90%. S. pneumoniae: Almost all strains (99%) were susceptible to PCG at the level less than 0.2 units/ml (0.12 microgram/ml). All strains were susceptible to various penicillins, cephalosporins, and cephamycins studied at the level less than 3 micrograms/ml. E. coli, K. pneumoniae and Proteus spp.: CTM, CFX and CMZ showed greater activity than CET and CEZ. Susceptible strains to the former antibiotics at the level less than 15 micrograms/ml were 93 approximately 94%, 82 approximately 95%, and 63 approximately 90%, respectively. Those to CET and CEZ were 61 approximately 83%, 85 approximately 92% and 53 approximately 58%, respectively. Among these cephalosporins, CMZ and CTM were the most effective, showing the least prevalence of resistance to these pathogens. H. influenzae: Susceptible strains (MICs less than 15 micrograms/ml) to ABPC, PIPC, CTM, CFX and CMZ were 80%, 81%, 84%, 55% and 71%, respectively. The majority of resistant strains to these beta-lactam antibiotics were sensitive to chloramphenicol, minocycline, doxycycline and erythromycin. P. aeruginosa, S. marcescens, E. aerogenes, Citrobacter and Achromobacter: CTM, CMZ and CFX were not effective against these pathogens.

Aminoglycosides↗
PubMed1985

Safety and efficacy of ticarcillin plus clavulanic acid in the treatment of infections of soft tissue, bone, and joint.

The efficacy and safety of ticarcillin plus clavulanic acid in the treatment of patients with infections of soft tissue, bone, and joint were evaluated in this open study. Clinical diagnoses included osteomyelitis, soft tissue abscess or ulcer, cellulitis, bite wound, traumatic or postoperative cellulitis, necrotizing fasciitis, septic arthritis, septic bursitis, and septic thrombophlebitis. Trauma or underlying disease such as diabetes mellitus or vascular insufficiency was common (more than 50 percent) in the patient population. Clinical efficacy was evaluable in 66 patients who received 3 g of ticarcillin and 0.1 g of clavulanic acid every four or six hours for a mean of 23.4 days. A satisfactory clinical response was observed in 92 percent of the patients. Major pathogens isolated were Enterobacteriaceae, anaerobic cocci, Staphylococcus aureus, and beta-hemolytic Streptococcus. Of the 143 isolates recovered from 55 bacteriologically evaluable cases, 87 percent were eradicated by therapy. Overall, a satisfactory bacteriologic outcome occurred in 93 percent of the patients, and the pathogen(s) persisted in 7 percent. More than 98 percent of the isolates were susceptible to ticarcillin plus clavulanic acid in vitro. Emergence of resistance during therapy occurred with three strains of Pseudomonas aeruginosa. Adverse drug-related reactions required discontinuation of treatment in two patients, although other minor abnormal laboratory findings were common. These results indicate that ticarcillin plus clavulanic acid offers safe and effective therapy for infections of soft tissue, bone, and joint.

Adult↗
PubMed1995

Explanation for false-positive urine cultures obtained by bag technique.

OBJECTIVE: To test whether a urine bag technique, previously shown in circumcised male infants 1 month to 1 year of age to yield no false-positive cultures, would give similar results in newborns (females and circumcised and uncircumcised males). DESIGN: Prospective study in which periurethral and urine specimens were obtained from healthy newborns. After the periurethral specimen was obtained, the perineum was washed and a urine bag applied. The urine bag was removed immediately after voiding and the urine was cultured. SETTING: Normal newborn nursery and pediatric hospital. SUBJECTS: Ninety-eight healthy full-term newborns (49 female and 49 male) admitted to the normal nursery during a 4-month period. MAIN RESULTS: Isolation of a pathogen from the bag urine reflected periurethral flora. In 20 (95%) of the 21 urine specimens from which a pathogen was isolated, the same pathogen was detected on the periurethra. Sixteen of the 21 urine cultures were falsely positive (> 10(4) colony-forming units of pathogen per milliliter). In 50 (98%) of the 52 urine samples that yielded no growth, the periurethral culture was also negative. In the remaining 25 urine samples in which nonpathogens were detected, the periurethra yielded nonpathogens or no growth. Thus, if a pathogen was isolated from a bag urine sample, the same pathogen was detected on the periurethra 95% of the time. Conversely, if the bag urine sample was negative for a pathogen, the periurethral culture was negative 100% of the time. The presence of a pathogen on the periurethra was more common in female than male neonates (16 of 49 vs four of 49; P = .004), and none of the 14 circumcised male neonates had a pathogen detected on their periurethra or in their urine. CONCLUSION: This study explains the finding of false-positive cultures with the bag technique. Pathogens detected in bag urine samples reflected pathogens on the periurethra. Until a bag collection technique that avoids contamination by periurethral flora can be developed, urethral catheterization and suprapubic aspiration remain the methods of choice for obtaining a urine specimen in female and uncircumcised male neonates.

Bacteria↗
PubMed1985

Phenotypic variations among enterotoxinogenic Escherichia coli from Swedish piglets with diarrhoea.

Escherichia coli strains causing diarrhoea in Swedish piglets were isolated; this investigation was made over a 20-year period, from 1964 to 1984. Many of the isolates belonged to O-groups 8, 141 and 149. These strains were separated into different phenotypes with the aid of a new method, "biochemical fingerprinting". This method has been especially designed to sort E. coli-isolates into various phenotypes based on a pattern of quantitatively measured biochemical reactions. It was found that most pathogenic isolates carrying O-antigen 8 belonged to the same phenotype. This phenotype was common in the 1960's, but later it disappeared from the population and was replaced by a wide variety of different phenotypes, most of them non-enterotoxinogenic, but still belonging to O-group 8. In O-group 141 one phenotype dominated in the 1960's, but in the 1970's a new phenotype appeared, which further increased in number in the 1980's. By contrast, in the O-group 149 practically all strains isolated during the 20-year period were found to carry the relevant virulence factors and belong to the same phenotype.

Animals↗
PubMed2003

Antibacterial activity of two plant extracts on eight burn pathogens.

Antibacterial activity of crude alcoholic extract of Datura alba and Celosia argentea leaves were studied against pathogens isolated from infected burn patients. The disc-diffusion method showed significant zone of lysis against all the pathogens studied and the results are comparable to the conventional antibiotic cream namely Silver Sulphadiazine (SSD). On comparing the efficiency of the two extracts, extract of D. alba exhibited more than 50% increase in antibacterial activity compared to C. argentea.

Bacteria↗
PubMed2004

Impact of prior therapy on the recovery and frequency of corneal pathogens.

OBJECTIVE: To document the impact of prior antibiotic therapy on the recovery of corneal pathogens. METHODS: Medical records and laboratory reports of 334 consecutive microbial keratitis patients examined from January to December 2000 were reviewed. Comparisons of pathogens, culture positive rate, recovery time, antibiotic sensitivity profile, delay in presentation, and final visual acuity were analyzed for patients treated before presentation and those who were not. The chi square test was used to determine statistical significance. RESULTS: Of the 334 patients, 56% were exposed to at least one course of topical antimicrobials before culture. Patients on therapy were only slightly more likely to be culture negative (P = 0.317) but significantly more likely to have a delay in pathogen recovery (P = 0.002). Patients given prior antibiotics took significantly longer to heal (P = 0.003). Gram-negative organisms (47.5%) were the most frequent pathogens isolated from all culture-positive patients, followed by gram positives (28.7%), fungi (15.8%), and parasites (2%). An increase and significant difference in the frequency of fungi (P = 0.000) and acanthamoeba was reserved for the pretreated group. Gram negative organisms were more often isolated from patients who had not been pretreated (P = 0.002). Pretreated patients were more like to have a pathogen resistant to 1 or more of the commonly prescribed ocular antibiotics (P = 0.02). CONCLUSIONS: There is a delay in starting microbiologic-guided antibiotic treatment in patients who have received empiric therapy. Nonbacterial corneal pathogens may be associated more frequently with patients on prior therapy.

Acanthamoeba↗
PubMed2004

Crystallization and preliminary X-ray crystallographic analyses of CMY-1 and CMY-10, plasmidic class C beta-lactamases with extended substrate spectrum.

Plasmid-encoded class C beta-lactamases, including CMY-1 and CMY-10, hydrolyze the lactam bonds of beta-lactam antibiotics, inducing therapeutic failure and a lack of eradication of clinical isolates by third-generation cephalosporins or cephamycins. Therefore, the enzymes are potential targets for developing agents against pathogens isolated from patients suffering from wound infection, urinary tract infection or pneumonia. CMY-1 and CMY-10 were purified and crystallized at 298 K. X-ray diffraction data from CMY-1 and CMY-10 crystals have been collected to 2.5 and 1.5 A resolution, respectively, using synchrotron radiation. The crystals of the two proteins are isomorphous and belong to the primitive monoclinic space group P2(1).

Cloning, Molecular↗
PubMed2000

[Microbiological monitoring for the causative agents of nosocomial infections (exemplified by resuscitation and intensive therapy units)].

More than 900 isolates from at least 1500 patients were tested within 1996-1998. Gram-negative organisms were the main pathogens isolated from patients with different forms of nosocomial complications such as late pneumonia, associated with artificial ventilation of the lungs, and various secondary wound or urinary tract infections. The prevalence of Pseudomonas aeruginosa was stated. Antibioticograms showed that the most active drugs were imipenem (more than 90 per cent of the susceptible isolates) and ticarcillin/clavulanate (48-58 per cent of the susceptible isolates). The activity of ticarcillin/clavulanate (Timentin) was practically the same as that of imipenem against 21 strains of P.aeruginosa isolated from the blood and cerebrospinal fluid of 21 patients with sepsis and 3 patients with secondary purulent meningitis.

Anti-Bacterial Agents↗
PubMed2002

[Changes of pathogenic bacteria in pediatric patients of septicemia and drug resistance there of in Zhejiang Children's Hospital 1991 approximately 2000].

OBJECTIVE: To investigate the changes of pathogenic bacteria detected from the blood culture of pediatric patients with septicemia in the past 10 years, and to observe the drug resistance thereof in the past two years. METHODS: The blood samples of 4 425 pediatric patients aged 0 approximately 14 with the diagnosis of septicemia 1991 approximately 2000 in Zhejiang Children's Hospital were cultured in broth (1991 approximately 1996) or VITA AER blood culture apparatus (1997 approximately 2000). Analytic Product Inc. (API ) system and KB paper strip method and VITEK automicroscan were used to identify the species and conduct drug resistance test. The results were interpreted according to the guideline of National Committee for Clinical Laboratory Standards. RESULTS: In the past 10 years, Gram-positive bacteria remained the more frequent pathogens than Gram-negative bacteria in pediatric patients with septicemia. The proportion of coagulase-negative staphylococcus (CNS) had been increasing and reached 69% in 2000. The proportions of Staphylococcus aureus and Escherichia coli decreased from 35.4% and 18.2% in 1991 to 5.3% and 1.5% in 2000. In the past two years, the drug resistance rate of staphylococci against penicillin and erythromycin were more than 90% and 70% respectively. The oxacillin resistance rate of CNS was 60.3%, significantly higher than that of Staphylococcus aureus (10.3%). No strain of Staphylococcus and Enterococcus resistant to vancomycin was found. Escherichia coli and Psudomonas aeruginosa and other species of Enterobacteriae were sensitive to imipenem/cilastin sodium, whereas the resistance rate of them to ampicillin and first generation cephalosporins was more than 50%. CONCLUSION: (1) Gram-positive bacteria are the predominant pathogens of pediatric patients with septicemia, with the species of Staphylococcus ranking first among which CNS is the main pathogen for infants and Staphylococcus aureus is the main pathogen for school children. (2) Escherichia coli is the most frequently found pathogenic Gram-negative bacterium in infants with septicemia whereas Salmonella in school children. (3) Drug resistance of isolated pathogenic bacteria in department of pediatrics is a serious problem. Monitoring the change of pathogen and the trends of antimicrobial resistance is very important in guiding therapy.

Adolescent↗