Escherichia coli Bcteriuria in pregnant women in Ghana: Antibiotic resistance pattern, Virulence Factors and Resistant genetic markers

The relevance of Escherichia coli associated bacteriuria infection in pregnant women is poorly understood, despite these strains sharing a similar virulence profile with other extra intestinal pathogenic E. coli producing severe obstetric and neonatal infections. We characterized and determined the antimicrobial susceptibility, resistant genes and virulence profiles of 82 E. coli isolates associated with asymptomatic bacteriuria in some pregnant in five very distinct hospitals in the Volta region from January, 2016 to April, 2016 using Kirby-Bauer disc diffusion and polymerase chain reaction. High levels of antimicrobial resistance was observed to Ampicillin (79.3%), Tetracycline (70.7%) and Cotrimoxazole (59.8%), except for Cefuroxime (32.9%). Resistant genes analyses revealed 58.5% were positive for BlaTEM and 14.6% for aph(3)-Ia(aphA2). Virulence factors (VFs) was more widespread in pregnant women in the 2nd and 3rd trimesters than 1st trimester. VFs relating to adhesion (papC and iha), Protectins (traT), aerobactin acquisition (iutA) and iron acquisition systems (fyuA and irp2) were more prevalent in the resistant E. coli isolates. This study provides additional evidence for a link in bacteriuria and transmission of extra-intestinal E. coli in pregnant women to cause multi-resistant severe obstetric or neonatal infections. Considering the involvement of extra-intestinal E. coli in infections, our results may be helpful to develop strategies to prevent maternal and/ neonatal infections. In addition continuous surveillance is required to guide appropriate antibiotic usage in pregnant women.

Clean catch midstream urine samples from the pregnant women were inoculated onto cysteine 125 lactose electrolyte deficient (CLED) agar and incubated at 37 0 C for 18 to 24 hours. Colonies 126 that appeared circular and yellow on CLED agar were considered to be potential E. coli [28]. 127 A representative colony on each plate was Gram stained and further tested using indole, methyl 128 red, citrate, Voges-Proskauer test and urease [28]. API 20E identification system (bioMerieux 129 SA, Marcy l"Etoile, France) was used to confirm the isolates before the identified isolates were 130 stored in 10% glycerol-trypticase soy broth at -70 0 C for further sensitivity and molecular 131 analyses testing.

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For the purpose of this study, the participants were put into 4 age groups (

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In total, forty seven ampicillin resistant isolates were found to contain Bla TEM (Table 6).

Distribution of Virulence factors gene 328
The distribution of the 82 E. coli isolates in relation to virulence genes from the various groups 329 of pregnant women revealed 75.6% (62 isolates) E. coli contained two or more virulence genes 330 (VFs) ( Table 6). The virulence score used to classify the ExPEC isolates was calculated using 331 the total number of VFs genes. Isolates were classified as ExPEC if they were positive for two 332 or more of the tested virulence genes (5). The iutA (aerobactin acquisition), papC and iha 333 (adhesins), fyuA and irp2 (iron capture systems), traT (protectins) were the common detected 334 genes, whereas usp (uropathogenic-specific proteins) and some of the adhesin genes (hra, ibeA,

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& papG1) were the least detected genes, sat (toxins) and papGII & papGIII (adhesion) was not 336 detected in any of the isolates. In addition, VFs was more widespread in pregnant women in 337 the 2 nd (30 isolates) and 3 rd (25 isolates) trimesters than 1 st trimester (12 isolates).

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In the tested pregnant women, all the E. coli isolates in pregnant women in the 1 st Trimester 339 were ExPEC isolates. Although pregnant women aged between 20 -29 years were more 341 their 2 nd trimesters aged between 20 -29 years (21 patients) had a higher prevalence of VFs.

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Out the 33 VFs positive E. coli isolates associated with pregnant women in their 2 nd trimester, 343 30 of the strains were positive for two or more of the tested virulence genes. Whilst a few (2) 344 pregnant women aged 40 -49 in their 3 rd trimesters haboured ExPEC isolates, 12 of the women 345 aged between 20 -29 were positive for ExPEC isolates.  with previous studies by Hamdan et al.,[49] in Sudan, Kawser et al.,[50]