Phenotypic Characterization of Escherichia Coli Isolated From Urine and Stool from Short Term and Long Term Catheterized Patients

Background: Uropathogenic strains of Escherichia coli possess a number of phenotypic characters which allow them to colonize the catheter and cause infection of the same and the chances of colonization by these micro-organisms increase with the duration of catheterization. Objectives: This study was carried out to understand the differences between the phenotypic characters between the strains of E.coli isolated from the urine and gut of short term catheterized (STC) and long term catheterized (LTC) patients. Materials and Methods: Urine from the catheter and stool sample was processed by standard methods. The following special tests like α-hemolysis, haemagglutination, cell surface hydrophobicity, serum bactericidal assay, biofilm formation and congo red binding assay were performed to detect the phenotypic characters of the isolated E.coli. Antibiotic susceptibility testing was performed by Kirby Bauer method as per the Clinical Laboratory Standards Institute. Results: Majority (93.75%, 75% and 81.25%) of the E.coli isolates from urine of LTC patients were positive for MRHA, cell surface hydrophobicity and resistant to serum killing respectively, while majority (93.75%) of the urine isolates from short term catheterization. On congo red agar, the majority (80% and 60%) of isolates producing rdar type of colony and biofilm respectively,were isolated from urine of long term catheterized patients. ESBL production was noted in 68.75% of the urine isolates from long term catheterized patients. Conclusion: Serum resistance and biofilm formation are significant assays in terms of differentiating between the short term and long term catheterization and by elucidating these mechanisms better, it may become easier to combat and prevent such infections

The trends of isolation and antimicrobial susceptibility of group B Streptococcus in urine culture: a 7-years cross sectional study

Background: Group B Streptococcus (GBS)/Streptococcus agalactiae (S. agalactiae) is a common rectovaginal colonizer, thereby a potential agent of neonatal and maternal infection. This study estimates the trends of isolation of GBS, its antimicrobial profile in urine culture and the demographic characteristics of these patients over a 7-year period. Methods: A record-based study was conducted, which included all the urine culture reports of GBS/S. agalactiae from January 2014 to December 2020. The trend of occurrence of GBS bacteriuria, demographic characteristics and antimicrobial susceptibility pattern were analyzed. Results: Out of 137 urine samples which grew GBS/S. agalactiae, 55(40.15%) were from antenatal women. Most of the isolates were from females (72.26%), with a male preponderance noted among the elderly population (age>60 years). The predominant age group affected were adults between 20 to 59 years. The majority of the isolates (60.58%) were susceptible to all the four tested antibiotics, namely, ciprofloxacin, nitrofurantoin, ampicillin and vancomycin. Ciprofloxacin resistance was observed in 32.85% (45/137) isolates, 5.84% (8/137) isolates were resistant to ampicillin and 2.92% (4/137) were resistant to nitrofurantoin. Conclusions: All the isolates were susceptible to vancomycin. GBS/S. agalactiae is an important agent of bacteriuria in antenatal women as well as in non-pregnant population, especially the elderly males. Emerging resistance to various group of antibiotics warrants routine susceptibility testing

Characterization of ceftriaxone-resistant Aeromonas spp. isolates from stool samples of both children and adults in Southern India

Background: Aeromonas species can cause a wide spectrum of illnesses varying from intestinal to extra intestinal and vary in their susceptibility to different antibiotics. The current study was undertaken to characterize the third generation cephalosporin-resistant strains of Aeromonas spp. which were isolated from stool specimens. Methods: Out of a total of 2780 stool samples, 29 Aeromonas spp. were identified, out of which, 9 were resistant to ceftriaxone by the Kirby-Bauer antibiotic testing method. These strains were subjected to minimum inhibitory concentration (MIC) determination by agar dilution for ceftriaxone. Phenotypic and genotypic testing of AmpC beta-lactamase and extended spectrum beta-lactamase (ESBL) were performed. Gene transfer was carried out to demonstrate transmissibility of these genetic elements by conjugation experiments. Results: Out of the 29 strains, 9 showed MIC of 654 \u3bcg/ml. Seven out of 9 showed presence of blaCTX-M, while 2 more strains showed the presence of inducible AmpC beta-lactamase and presence of MOX gene. Gene transfer experiments showed that these elements were transmissible to recipient ( Escherichia coli J53 strain) in the presence of ceftriaxone. Conclusions: Dissemination of these resistance determinants like plasmids is pivotal in the spread of these resistance genes into the aquatic environment into organisms like Aeromonas. This may further limit the future use of antibiotics for the treatment of diarrhoeal diseases. Hence, detection and antibiotic susceptibility testing of Aeromonas spp. should be performed when isolated from stool samples

Exacerbation of ulcerative colitis due to Edwardsiella tarda infection

Infectious gastroenteritis can lead to exacerbations of inflammatory bowel disease (IBD) such as ulcerative colitis, which warrants appropriate and timely control with the initiation of specific antibacterial therapy. Herein, we discuss a patient who had presented with an exacerbation of ulcerative colitis due to an infectious gastroenteritis caused by Edwardsiella tarda and had responded to the appropriate antibacterial therapy. This study outlines the importance of a culture of stool samples in all cases of IBD with acute exacerbations

Increasing Antimicrobial Resistance of Vibrio cholerae O1 Biotype El Tor Strains Isolated in a Tertiary-care Centre in India

The antimicrobial susceptibility patterns are on constant change with the recent emergence of multidrugresistant strains of most bacteria. Results of recent studies in India showed that most isolates of Vibrio cholerae O1 were resistant to the commonly-used antibiotics. The study was conducted to determine the antibiotic susceptibility patterns of V. cholerae O1 isolated during 2008-2010 at the hospital of the Jawaharlal Nehru Institute of Post Graduate Medical Education and Research, Puducherry, India. In total, 154 strains of V. cholerae O1 from 2,658 stool specimens were reported during January 2008\u2013December 2010\u201434 in 2008, 2 in 2009, and 118 in 2010. The isolates of V. cholerae O1 were subjected to antimicrobial susceptibility testing using the Kirby-Bauer method. The antibiotic disks tested were tetracycline (30 \u3bcg), furazolidone (100 \u3bcg), ampicillin (10 \u3bcg), ceftriaxone (30 \u3bcg), and ciprofloxacin (5 \u3bcg). Escherichia coli ATCC 25922 was used as the control organism. The minimum inhibitory concentrations (MICs) of ceftriaxone, ciprofloxacin, and tetracycline were determined using the agar dilution method for all the strains. The E-test method was used for the strains which had either intermediate resistance or were resistant to the antibiotics by the agar dilution method. The results of the agar dilution corroborated the results of the E-test. The MIC of ceftriaxone in 151 strains was <2 \u3bcg/mL while it was 16 \u3bcg/mL in three strains; the latter three strains were resistant to ceftriaxone by the disc-diffusion test. The MIC of ciprofloxacin in 150 strains was <0.5 \u3bcg/mL while the MIC of tetracycline was <1 \u3bcg/mL. In the remaining four strains, the MIC of tetracycline was >32 \u3bcg/mL, and the MIC of ciprofloxacin was >8 \u3bcg/mL. These four strains were resistant to both tetracycline and ciprofloxacin by the disc-diffusion test and were exclusive of the three ceftriaxone-resistant strains. The majority of the isolates were obtained from children aged 0-5 year(s)\u201470.3% (83 of 118) and 41.2% (14 of 34) were reported in 2010 and 2008 respectively. Since treating severe cases of cholera with antibiotics is important, the continuing spread of resistance in V. cholerae to the most important agents of therapy is a matter of concern. Also, chemoprophylaxis with antimicrobial agents is likely to become even more difficult

Clinical and Microbiological Profiles of Shigellosis in Children

Shigellosis presents with varied clinical features are dictated by the species involved, virulence factors of the strain, and the host immune status. We studied the species, virulence genes, and antibiotic susceptibility pattern of the Shigella strains isolated from 33 children aged less than 12 years, with clinical features of shigellosis. Identification and antibiotic sensitivity of Shigella species were done using disc diffusion and E-test. Multiplex PCR was done for the detection of virulence genes (ipaH, ial, set1A, set1B, sen, and stx) and ESBL genes. Parents of the children were interviewed using structured questionnaire to assess the severity of the disease; 26 (79%) of the isolates were Shigella flexneri . Ciprofloxacin and ceftriaxone resistance was seen in 23 (69%) and 3 (9%) Shigella isolates respectively. Two ceftriaxone-resistant strains were found to harbour blaCTX gene and the third blaTEM gene. Virulence gene ipaH was detected in 100% of strains while ial, sen, set1A, and set1B were detected in 85%, 61%, 48%, and 48% respectively

A study of virulence and antimicrobial resistance pattern in diarrhoeagenic Escherichia coli isolated from diarrhoeal stool specimens from children and adults in a tertiary hospital, Puducherry, India

Background: Emergence of atypical enteropathogenic Escherichia coli (EPEC) and hybrid E. coli (harboring genes of more than one DEC pathotypes) strains have complicated the issue of growing antibiotic resistance in diarrhoeagenic Escherichia coli (DEC). This ongoing evolution occurs in nature predominantly via horizontal gene transfers involving the mobile genetic elements like integrons notably class 1 integron. This study was undertaken to determine the virulence pattern and antibiotic resistance among the circulating DEC strains in a tertiary care center in south of India. Methods: Diarrhoeal stool specimens were obtained from 120 children (< 5 years) and 100 adults (> 18 years), subjected to culture and isolation of diarrhoeal pathogens. Conventional PCR was performed to detect 10 virulence and 27 antimicrobial resistance (AMR) genes among the E. coli isolated. Results: DEC infection was observed in 45 (37.5%) children and 18 (18%) adults, among which [18 (40%), 10 (10%)] atypical EPEC was most commonly detected followed by [6 (13.3%), 4 (4%)] ETEC, [5 (11.1%) 2 (2%)] EAEC, [(3 (6.6%), 0 (0%)] EIEC, [3 (6.6%), 0 (0%] typical EPEC, and [4 (8.8%), 1 (1%)] STEC, and no NTEC and CDEC was detected. DEC co-infection in 3 (6.6%) children, and 1(1%) adult and sole hybrid DEC infection in 3 (6.6%) children was detected. The distribution of sulphonamide resistance genes (sulI, sulII, and sulIII were 83.3 and 21%, 60.41 and 42.1%, and 12.5 and 26.3%, respectively) and class 1 integron (int1) genes (41.6 and 26.31%) was higher in DEC strains isolated from children and adults, respectively. Other AMR genes detected were qnrS, qnrB, aac(6\u2019)Ib-cr, dhfr1, aadB, aac(3)-IV, tetA, tetB, tetD, catI, blaCTX, blaSHV, and blaTEM. None harbored qnrA, qnrC, qepA, tetE, tetC, tetY, ermA, mcr1, int2, and int3 genes. Conclusions: Atypical EPEC was a primary etiological agent of diarrhea in children and adults among the DEC pathotypes. Detection of high numbers of AMR genes and class 1 integron genes indicate the importance of mobile genetic elements in spreading of multidrug resistance genes among these strains

Fibre laser development for sensor applications

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Pathogenesis and Laboratory Diagnosis of Childhood Urinary Tract Infection

Urinary tract infection (UTI) is one of the most common infections of childhood. The clinical presentations are mostly non-specific or mild. As any episode of UTI can potentially damage the kidneys, timely diagnosis and treatment are necessary to prevent renal damage. Incidence of UTI varies depending on the age, gender, and race of the child. UTIs in children are commonly caused by bacteria, though viruses, fungi, and parasites are also occasionally involved. The pathogenesis of UTI is complex where several host and pathogen factors influence the course of the disease and its outcome. Urine culture is still considered the gold standard method for the diagnosis of UTI. The means of obtaining urine samples from children for culture involves urethral catheterisation and suprapubic aspiration. The conventional methods of antibiotic susceptibility testing are labour intensive and time exhaustive. With the advent of technology, many automated platforms are available which are rapid, involve less volume of the culture or the sample, and have high accuracy