Antibiotic Susceptibility Pattern of Bacteria Causing Urinary Tract Infection.

BACKGROUND: Urinary tract infection is one of the commonest infectious diseases worldwide. This study was carried out to determine the antimicrobial susceptibility pattern of bacteria causing urinary tract infection visiting Kathmandu University Hospital. METHODS: A total of 3,500 urine samples were processed and antibiotic resistance pattern was determined following Clinical Laboratory Standard Institute guidelines. Patients' information was obtained after informed consent. RESULTS: Total number of samples with positive growth was 434 (12.40%). 331 (76.27%) of the isolates were Escherichia coli followed by Klebsiella pneumoniae, Enterococcus spp., Pseudomonas aeruginosa, Staphylococcus saprophyticus, Proteus mirabilis, Enterobacter species, Klebsiella oxytoca, Citrobacter freundii, Proteus vulgaris, Staphylococcus aureus and Acinetobacter species. Over all 224 (51.61%) were multidrug resistant strains. All strains were sensitive to colistin, vancomycin and linezolid. Over all ampicillin and cefazolin had least sensitivity. Multidrug resistant strains were detected more among elderly patients with complicated urinary tract infection and diabetes which was 25 (83.33%) compared to elderly patients with uncomplicated urinary tract infection and having no diabetes or any other comorbid illnesses which was only 11(22.22%) (p-value<0.05). 21 (70.00%) of the pregnant females had multidrug resistant isolates and only 18 (36.73%) of pediatric age group patients had multidrug resistant isolates (p-value<0.05) Conclusion: Drug-resistant bacteria were observed in urine samples. Effective treatment and prevention of urinary tract infection need detailed microbiological diagnosis and drug susceptibility testing.

Antimicrobial Susceptibility Pattern of Gram-Negative Bacteria Causing Lower Respiratory Tract Infections in Kathmandu University Hospital.

BACKGROUND: Respiratory tract infection due to Gram-negative bacteria is a common cause of morbidity and mortality worldwide. This study was carried out to determine the antimicrobial susceptibility pattern of Gram-negative bacteria from patients with lower respiratory tract infection visiting Kathmandu University Hospital. METHODS: A total of 3,403 respiratory samples including sputum and endotracheal aspirates were processed and antibiotic resistance pattern was determined following Clinical Laboratory Standard Institute guidelines. Patients' information was obtained after informed consent. RESULTS: Growth of Gram-negative bacteria was 210 (6.17%). 83(39.52%) were Klebsiella pneumoniae followed by Escherichia coli, Pseudomonas aeruginosa, Acinetobacter species, Klebsiella oxytoca, Enterobacter species, Proteus mirabilis and Haemophilus influenzae. 151(71.90%) isolates were multidrug resistant. None of the strains were resistant to colistin. 51(24.29%) were resistant to carbapenem and out of these 3(1.43%) were metallo-? lactamase producers. 89(65.92%) of the patients having both pneumonia along with other respiratory illnesses were above 60 years of age indicating that old age might be a predisposing factor. (p value is less than 0.0001). 92(81.42%) of patients of age above 60 years had multidrug resistant isolates indicating that old age might be a predisposing factor for getting infection my multidrug resistant isolates. (p value equals 0.0012) Among 36 diabetic patients 33(91.67%) had multidrug resistant isolates. Whereas out of 174 non-diabetic patients only 118(67.82%) had multidrug resistant isolates (p value equals 0.0037). CONCLUSIONS: Multidrug-resistant Gram negative bacteria were observed in respiratory samples. Effective treatment of lower respiratory tract infection need detailed microbiological diagnosis and drug susceptibility testing.

Antibiotic Susceptibility Pattern of Bacterial Pathogens Isolated from Infected Lesions.

BACKGROUND: Wound infection with multidrug resistant bacteria along with risk factors is a major burden and challenge to the health care persons. This study focuses on antibiotic susceptibility pattern of bacterial isolates and risk factors of patients with infected wounds. METHODS: This was a cross-sectional study conducted between November 2017 to June 2018 in Kathmandu University Hospital. Pus sample and wound swabs collected from patients during the study period were included. All microbiological processing were done following standard guidelines and patient's information was collected following ethical guidelines. RESULTS: Total number of patients observed for wound infection was 2,763. Pathogenic bacteria were detected in 252(9.12%) samples. 167(66.27%) were multidrug resistant. 118(46.82%) had risk factors. Among risk factors 14 had malignancy, 12 had diabetes, 32 were above age 60 without other risk factors, 45 received prior antibiotics and had critical illness and 15 were renal failure patients. Multidrug resistant bacteria was detected more among patients with risk factors 101(85.59%) in comparison to patients without risk factor 66(49.25%). When p value was calculated it was found significant. (p=<0.05). CONCLUSIONS: Significant amount of multidrug resistant bacteria were found in wounds of patients with risk factors. Prevention of wound infection by taking care of postoperative wounds, controlling and treating the risk factors, avoiding misuse of antibiotics and early microbiological analysis of infected wound might help to reduce the burden in healthcare centers.

Molecular and Clinical Epidemiology of Salmonella Paratyphi A Isolated from Patients with Bacteremia in Nepal.

Little is known about the epidemiology of typhoid and paratyphoid fever in Nepal. We aimed to elucidate the molecular and clinical epidemiology of Salmonella Paratyphi A in Nepal. Isolates were collected from 23 cases of bacteremia due to S. Paratyphi A between December 2014 and October 2015. Thirteen patients (57%) were male, and the median age was 21 years. None of the patients had an underlying chronic disease. All S. Paratyphi A isolates were sensitive to ampicillin, trimethoprim/sulfamethoxazole, ceftriaxone, and chloramphenicol. All isolates were resistant to nalidixic acid and were categorized as intermediately susceptible to levofloxacin. Phylogenetic analysis revealed close relatedness among the isolates, including several clonal groups, suggesting local spread. Patients with bacteremia due to S. Paratyphi A in Kathmandu, Nepal, were relatively young and nondebilitated. Improving control of S. Paratyphi infections should focus on effective infection control measures and selection of empirical therapy based on current resistance patterns.

Correction for Miyoshi-Akiyama et al., "Comparative Genome Analysis of Extended-Spectrum-ß-Lactamase-Producing Escherichia coli Sequence Type 131 Strains from Nepal and Japan".

[This corrects the article DOI: 10.1128/mSphere.00289-16.].

Comparative Genome Analysis of Extended-Spectrum-ß-Lactamase-Producing Escherichia coli Sequence Type 131 Strains from Nepal and Japan.

The global spread of extended-spectrum-ß-lactamase (ESBL)-producing Escherichia coli (ESBL-E. coli) has largely been driven by the pandemic sequence type 131 (ST131). This study aimed to determine the molecular epidemiology of their spread in two Asian countries with contrasting prevalence. We conducted whole-genome sequencing (WGS) of ESBL-E. coli ST131 strains collected prospectively from Nepal and Japan, two countries in Asia with a high and low prevalence of ESBL-E. coli, respectively. We also systematically compared these genomes with those reported from other regions using publicly available WGS data for E. coli ST131 strains. Further, we conducted phylogenetic analysis of these isolates and all genome sequence data for ST131 strains to determine sequence diversity. One hundred five unique ESBL-E. coli isolates from Nepal (February 2013 to July 2013) and 76 isolates from Japan (October 2013 to September 2014) were included. Of these isolates, 54 (51%) isolates from Nepal and 11 (14%) isolates from Japan were identified as ST131 by WGS. Phylogenetic analysis based on WGS suggested that the majority of ESBL-E. coli ST131 isolates from Nepal clustered together, whereas those from Japan were more diverse. Half of the ESBL-E. coli ST131 isolates from Japan belonged to virotype C, whereas half of the isolates from Nepal belonged to a virotype other than virotype A, B, C, D, or E (A/B/C/D/E). The dominant sublineage of E. coli ST131 was H30Rx, which was most prominent in ESBL-E. coli ST131 isolates from Nepal. Our results revealed distinct phylogenetic characteristics of ESBL-E. coli ST131 spread in the two geographical areas of Asia, indicating the involvement of multiple factors in its local spread in each region. IMPORTANCE The global spread of ESBL-E. coli has been driven in large part by pandemic sequence type 131 (ST131). A recent study suggested that, within E. coli ST131, certain sublineages have disseminated worldwide with little association with their geographical origin, highlighting the complexity of the epidemiology of this pandemic clone. ST131 bacteria have also been classified into four virotypes based on the distribution of certain virulence genes. Information on virotype distribution in Asian ST131 strains is limited. We conducted whole-genome sequencing of ESBL-E. coli ST131 strains collected in Nepal and Japan, two Asian countries with a high and low prevalence of ESBL-E. coli, respectively. We systematically compared these ST131 genomes with those reported from other regions to gain insights into the molecular epidemiology of their spread and found the distinct phylogenetic characteristics of the spread of ESBL-E. coli ST131 in these two geographical areas of Asia.

Clinical epidemiology and molecular analysis of extended-spectrum-ß-lactamase-producing Escherichia coli in Nepal: characteristics of sequence types 131 and 648.

Recently, CTX-M-type extended-spectrum-ß-lactamase (ESBL)-producing Escherichia coli strains have emerged worldwide. In particular, E. coli with O antigen type 25 (O25) and sequence type 131 (ST131), which is often associated with the CTX-M-15 ESBL, has been increasingly reported globally; however, epidemiology reports on ESBL-producing E. coli in Asia are limited. Patients with clinical isolates of ESBL-producing E. coli in the Tribhuvan University teaching hospital in Kathmandu, Nepal, were included in this study. Whole-genome sequencing of the isolates was conducted to analyze multilocus sequence types, phylotypes, virulence genotypes, O25b-ST131 clones, and distribution of acquired drug resistance genes. During the study period, 105 patients with ESBL-producing E. coli isolation were identified, and the majority (90%) of these isolates were CTX-M-15 positive. The most dominant ST was ST131 (n = 54; 51.4%), followed by ST648 (n = 15; 14.3%). All ST131 isolates were identified as O25b-ST131 clones, subclone H30-Rx. Three ST groups (ST131, ST648, and non-ST131/648) were compared in further analyses. ST648 isolates had a proportionally higher resistance to non-ß-lactam antibiotics and featured drug-resistant genes more frequently than ST131 or non-ST131/648 isolates. ST131 possessed the most virulence genes, followed by ST648. The clinical characteristics were similar among groups. More than 38% of ESBL-producing E. coli isolates were from the outpatient clinic, and pregnant patients comprised 24% of ESBL-producing E. coli cases. We revealed that the high resistance of ESBL-producing E. coli to multiple classes of antibiotics in Nepal is driven mainly by CTX-M-producing ST131 and ST648. Their immense prevalence in the communities is a matter of great concern.

Intravascular catheter-related infections in an Indian tertiary care hospital.

INTRODUCTION: This study had two objectives: 1) to determine the clinical and microbiological profiles of patients developing intravascular catheter-related local (localized catheter colonization and exit site) and systemic infections and their predisposing factors; 2) to study the antibiotic sensitivity patterns of the organisms isolated. METHODOLOGY: This case-control study was conducted over 19 months involving 232 patients at a tertiary care hospital. Non-tunneled central venous catheters and midline catheters were the two types studied. Catheter tips were processed using Maki's roll plate and endoluminal flush techniques. Blood cultures were drawn under strict aseptic precautions and processed by the BacT ALERT system. A "case" was any patient with proven localized catheter colonization, exit site infection or blood-stream infection and a "control" was any patient from whom the intravascular catheter yielded no organism in semi-quantitative cultures. RESULTS AND CONCLUSIONS: The incidence of catheter-related blood-stream infections (CRBSI) in our institute was 8.75 per 1,000 catheter days. The commonest organisms causing local infections were coagulase-negative Staphylococci, and those causing CRBSI were Staphylococcus aureus. Multidrug-resistant organisms accounted for 30.2% of the infections. Risk factors for development of catheter-related infections included an immune compromised state, duration of the catheter in situ, femoral venous cannulation, and triple lumen catheters. Choice of venous cannulation to minimize the risk of catheter-related infection in ascending order for risk of infection is the subclavian vein, jugular vein, basilic vein and then the femoral vein. There was no role for empirical antibiotic therapy to prevent intravascular catheter-related local or systemic infections.