Clinical characterization and antimicrobial resistance of Escherichia coli in pediatric patients with urinary tract infection at a third level hospital of Quito, Ecuador

Epidemiology of community origin of major multidrug-resistant ESKAPE uropathogens in a paediatric population in South-East Gabon

BACKGROUND

Urinary tract infections (UTIs) in children are very common. They are often associated with a high risk of sepsis and death. In recent years, antibiotic-resistant uropathogens ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacteriaceae) are increasingly encountered in UTIs. These bacteria, usually multidrug-resistance (MDR), extensive drug-resistance (XDR), pandrug-resistance (PDR), Extended-spectrum cephalosporin-resistance (ESC), Usual Drug Resistance (UDR), Difficult-to-Treat Resistance (DTR) and Carbapenem-resistance Enterobacteriales (CRE), represent a global threat for the management of paediatric UTIs. The aim of this study was to determine the epidemiology of community origin and antibiotic sensitivity of major ESKAPE uropathogens in paediatric UTIs in South-East Gabon.

METHODS

The study involved 508 children aged 0-17 years. Identification of bacterial isolates was carried out using Vitek-2 compact automated system and the antibiogram with the disk diffusion and microdilution methods according to the European Committee on Antimicrobial Susceptibility Testing recommendations. Logistic regression analysis was used to assess the impact of patients' socio-clinical characteristics on uropathogens phenotype in both univariate and multivariate analysis.

RESULTS

The prevalence of UTIs was 59%. E. coli (35%) and K. pneumoniae (34%) were the main ESKAPE involved in UTIs followed by Enterococcus spp. (8%) and S. aureus (6%). Among major ESKAPE, DTR-E. coli (p = 0.01), CRE-E. coli (p = 0.02) and XDR-E. coli (p = 0.03), Trimethoprim-sulfamethoxazole-resistant bacteria (p = 0.03) were associated with abdomino-pelvic pain. While MDR-E. coli (p < 0.001), UDR-E. coli (p = 0.02), ESC-E. coli (p < 0.001), MDR- Enterococcus (p = 0.04), UDR- Enterococcus (p = 0.02), bacteria resistant to Ampicillin (p < 0.01), Cefotaxime (p = 0.04), Ciprofloxacin (p < 0.001), Benzylpenicillin (p = 0.03) and Amikacin (p = 0.04) were more frequent among male children. MDR-Enterococcus (p < 0.01), bacteria resistant to Amoxicillin-clavulanic acid (p = 0.03), Cefalotin (p = 0.01), Ampicillin (p = 0.02) and Gentamicin (p = 0.03) were associated with treatment failure. In addition, Trimethoprim-sulfamethoxazole-resistant bacteria (p = 0.03) was associated with recurrent UTIs while those resistant to Ciprofloxacin was associated with pollakiuria (p = 0.01) and urinary burning (p = 0.04). Furthermore, UDR-K. pneumoniae (p = 0.02) was more frequent in neonates and infants.

CONCLUSION

This study determined the epidemiology of ESKAPE uropathogens in paediatric UTIs. It found a high prevalence of paediatric UTIs associated with children's socio-clinical characteristics and diverse bacterial antibiotic resistance phenotypes.

Efficacy of Urine Dipstick Test in Diagnosing Urinary Tract Infection and Detection of the blaCTX-M Gene among ESBL-Producing Escherichia coli

A urine dipstick test used for prompt diagnosis of urinary tract infection (UTI) is a rapid and cost-effective method. The main objective of this study was to compare the efficacy of the urine dipstick test with culture methods in screening for UTIs along with the detection of the bla_CTX-M gene in extended spectrum β-lactamase (ESBL)-producing Escherichia coli. A total of 217 mid-stream urine samples were collected from UTI-suspected patients attending Bharatpur Hospital, Chitwan, and tested by dipstick test strip (COMBI-10SL, Germany) prior to the culture. E. coli isolates were identified by standard microbiological procedures and subjected to antimicrobial susceptibility testing by Kirby Bauer disc diffusion method following CLSI guideline. Primary screening of ESBL-producing E. coli isolates was conducted using ceftriaxone, cefotaxime and ceftazidime discs and phenotypically confirmed by combined disk diffusion test. Plasmid DNA of ESBL-producing strains was extracted by phenol-chloroform method and subjected to PCR for detection of the bla_CTX-M gene. Out of 217 urine samples, 48 (22.12%) showed significant bacteriuria. Among 46 (21.20%) Gram negative bacteria recovered, the predominant one was E. coli 37 (77.08%) of which 33 (89.19%) were multidrug resistant (MDR). E. coli isolates showed a higher degree of resistance towards cefazolin (62.16%) while 81.08% of the isolates were sensitive towards amikacin followed by nitrofurantoin (70.27%). Among 14 (37.84%) phenotypically confirmed ESBL isolates, only eight (21.62%) isolates carried the bla_CTX-M gene. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of urine dipstick test were 43.75%, 77.51%, 35.59% and 82.91%, respectively. Besides, the use of dipstick test strip for screening UTI was associated with many false positive and negative results as compared to the gold standard culture method. Hence, dipstick nitrite test alone should not be used as sole method for screening UTIs.

High quantities of multidrug-resistant Escherichia coli are present in the Machángara urban river in Quito, Ecuador

Urban river pollution by multidrug-resistant (MDR) bacteria constitutes an important public health concern. Epidemiologically important strains of MDR Escherichia coli transmissible at the human-animal-environment interfaces are especially worrying. Quantifying and characterizing MDR E. coli at a molecular level is thus imperative for understanding its epidemiology in natural environments and its role in the spread of resistance in precise geographical areas. Cefotaxime-resistant E. coli was characterized along the watercourse of the major urban river in Quito. Our results showed high quantities of cefotaxime-resistant E. coli (2.7 × 10³-5.4 × 10⁵ CFU/100 mL). The antimicrobial resistance index (ARI) revealed the exposure of the river to antibiotic contamination, and the multiple antibiotic resistance index indicated a high risk of contamination. The bla_CTX-M-15 gene was the most prevalent in our samples. Isolates also had class 1 integrons carrying aminoglycoside-modifying enzymes and folate pathway inhibitors. The isolates belonged to phylogroups A, B1 and D. Clonal complex 10 was found to be the most prevalent (ST10, ST44 and ST 167), followed by ST162, ST394 and ST46. Our study provides a warning about the high potential of the major urban river in Quito for spreading the epidemiologically important MDR E. coli.

Clinical, etiological and antimicrobial susceptibility profile of pediatric urinary tract infections in a tertiary care hospital of Nepal

Background

Urinary tract infection (UTI) is one of most common pediatric infections. The study was designed to assess the clinical profile, common bacterial microorganisms causing UTI and their antimicrobial susceptibility patterns at B. P. Koirala Institute of Health Sciences (BPKIHS) hospital.

Methods

This is a prospective cross-sectional study conducted at Department of Microbiology and Infectious Diseases for 6 months (January to June 2018). A total of 1962 non-repetitive urine specimens (midstream, nappy pad, catheter aspirated) of pediatric patients (0–14 years age) suspected of UTI were obtained in the Microbiology laboratory. Clinical data was obtained from requisition form and hospital software. Culture and bacterial identification was done by using standard microbiological guidelines. Antimicrobial susceptibility testing was done by Kirby-Bauer disc diffusion method following clinical and laboratory standards institute (CLSI) guidelines. Resistance to methicillin and vancomycin were confirmed by calculating minimum inhibitory concentration using broth dilution method.

Results

Among 1962 samples, 314 (16%) were positive for bacterial infection. Fever, irritability and poor feeding was the most common symptoms in neonates while older children presented with fever and urinary symptoms. E. coli was reported the most common etiological agent (53%), followed by Enterococcus faecalis (22%), Klebsiella pneumoniae (7%) and Staphylococcus aureus (7%). Multidrug resistant (MDR) isolates accounted for 32% of isolates, while 5% were extensively drug resistant (XDR). Fourty percentage of gram-negative bacilli were ESBL producer, 38% of S. aureus were methicillin resistant Staphylococcus aureus (MRSA) and 5% E. faecalis were vacomycin resistant enterococci (VRE). E coli was highly resistant to Ampicillin (87%), Ceftriaxone (62%) and Ofloxacin (62%). Amikacin (11% resistance) and Nitrofurantoin (5% resistance) are the most effective drugs for gram-negative bacilli (GNB) while vancomycin and linezolid are functional against gram-positive cocci.

Conclusions

High-level antimicrobial resistance was observed in pediatric UTI with alarming incidence superbugs like MDR, XDR, ESBL and MRSA. Regular surveillance should be carried out to determine the local prevalence of organisms and antimicrobial susceptibilities in order to guide the proper management of children.