AiM Advances in Microbiology 2165-3402 Scientific Research Publishing 10.4236/aim.2018.83012 AiM-83183 Articles Biomedical&Life Sciences Urinary Tract Infection among Pregnant Women at Pumwani Maternity Hospital, Nairobi, Kenya: Bacterial Etiologic Agents, Antimicrobial Susceptibility Profiles and Associated Risk Factors Hellen A. Onyango 1 * Carolyne Ngugi 2 John Maina 1 John Kiiru 3 Department of Medical Microbiology, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya Centre of Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya Department of Medical Microbiology, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya * E-mail:honyango79@gmail.com(HAO); 21 03 2018 08 03 175 187 10, January 2018 18, March 2018 21, March 2018 © Copyright 2014 by authors and Scientific Research Publishing Inc. 2014 This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/

Urinary Tract Infections (UTIs) during pregnancy are among the most common infections worldwide and can lead to poor perinatal and maternal outcomes. This study determined the prevalence of UTIs during pregnancy, associated risk factors and antimicrobial susceptibility profiles of associated bacterial pathogens. A cross-sectional study was conducted among 210 pregnant women attending antenatal clinic at Pumwani Maternity hospital. Their social-demographic profiles were obtained using a structured questionnaire. Cultures were done from midstream urine and antimicrobial susceptibility testing determined using the disc diffusion test. The overall prevalence of UTI was 15.7% regardless of the women’s age, parity and stage of gestation. Prevalence of asymptomatic and symptomatic bacteriuria was 4.3% and 11.4% respectively. Material of undergarment and frequency of changing the undergarments were found to contribute significantly to the acquisition of UTI (P < 0.05). E. coli was the most predominant UTI organism at (44.5%) followed by K. pneumoniae (21.2%) and S. aureus (15.1%). Almost a half (over 49%) of all Gram-negative organisms showed resistance prevalence against third generation cephalosporins, fluoroquinolones, Sulfamethoxazole-Trimethoprim, Cefoxitin, Nitrofurantoin and Amoxicillin-clavulanic acid. Gram-positive strains were susceptible to Amoxicillin-clavulanic acid, Nitrofurantoin, Linezolid and Ofloxacin. The prevalence of multi-drug resistance (MDR) in all study isolates was 96%. Our data suggest a serious resistance trend among UTI strains and more should be done to slow down this trend. Pregnant women should be screened by urine culture and treatment be guided by the antimicrobial susceptibility data.

Urinary Tract Infection Pregnancy Risk Factors Antimicrobial Resistance ESBL MRSA MDR 1. Introduction

In developing countries, UTIs are among the most common health problems affecting women in their reproductive ages. Pregnant women are more susceptible to UTIs due to a combination of hormonal and physiologic changes that predispose them to bacteriuria [1] . The incidence of acute pyelonephritis in pregnant women is also significantly increased [2] . Factors such as history of recurrent urinary tract infection, diabetes, low social economic status, increasing maternal age, multiparity, and anatomical abnormalities of the urinary tract have also been associated with a two fold increase in bacteriuria during pregnancy [2] , but the risk factors associated with UTIs in Africa remains poorly investigated.

Globally, the prevalence of UTI in pregnancy ranges between 13% - 33% with symptomatic bacteriuria occurring in 1% - 18% while asymptomatic cases are noted in 2% - 10% of women [3] . The prevalence has remained constant and most of the recent observational studies, including those from developing countries, report almost similar rates [2] . The most common agent implicated in symptomatic and asymptomatic bacteriuria is Escherichia coli that is responsible for 70% - 80% of the infections [4] . Other microorganisms include Staphylococcus spp., Klebsiella pneumoniae, Proteus spp., Pseudomonas aeruginosa, Enterococcus spp. and Acinetobacter [5] . Past studies indicate that UTI among pregnant mothers in Kenya range from 10% - 19% [6] . However, most of these studies concentrate on selected bacterial pathogens and the larger spectrum of bacterial etiologic agents remains unknown. Furthermore, the socio-demographic and lifestyle factors associated with UTIs among pregnant women in Kenya remain uninvestigated.

In many hospitals in developing countries such as Kenya, routine urine culture is not carried out even for antenatal mothers. Currently, most patients are treated empirically without culture and antimicrobial susceptibility testing (AST) and treatment is therefore based on empiric guidelines that are rarely updated [7] . Even where UTI tests are done, only dipstick analysis and direct wet microscopy of urine are used, but these tests have poor positive and negative predictive values to detect bacteriuria particularly in asymptomatic persons [8] . We hypothesize that the overreliance on these methods and absence of culture and susceptibility testing have partially led to under-diagnosis of UTIs and this may be fueling the rising cases of treatment failure. In standard urine culture, a colony count of 105 CFU/ml is usually considered significant for infection [8] , but there’s missing data regarding the phenotypic characteristics of isolates whose counts fall below this threshold. Currently, such counts are regarded as contaminants. It is therefore not known if such counts represent a receding infection or an infection that is establishing. In this study, we compared the results of antimicrobial resistance phenotypes from UTI cases and those normally regarded as contaminants.

Results of this study provide critical data to care givers and health planners regarding diagnosis, common etiological agents and probable treatment options with regard to antimicrobial resistance. This study also identified associated risk factors for UTI amongst pregnant women attending antenatal clinic at Pumwani Maternity Hospital (The largest antenatal clinic in Kenya).

 2. Materials and Methods 2.1. Study Site

This was a cross sectional study carried out at Pumwani Maternity Hospital, an obstetric and referral hospital for expectant mothers in Nairobi, the Kenyan capital. The study targeted pregnant women seeking antenatal care services at the Hospital.

 2.2. Sampling Method

Systematic random sampling technique was employed in recruiting participants until the expected study sample was attained. A structured questionnaire was used for gathering socio-demographic and lifestyle data from the participants. Participants were instructed on how to collect clean-catch midstream urine after signing the consent form. Each sample bottle had a date of collection and bar-code linked to the participant's questionnaire which was in turn linked to confidential patient information file.

 2.3. Urine Culture

Urine aliquots of 10 µl were plated directly on CLED, MacConkey and blood agar plates and incubated aerobically at 35˚C - 37˚C for 24 hours. Colony counts yielding bacterial growth of ≥100,000 (105) CFU/ml or more of pure isolates were deemed significant UTI cases whereas those yielding lower values were deemed as contaminants. At least 3 colonies of similar morphology per patient were randomly selected from UTI plates and purified before biochemical identification. Gram stain was done for all colonies analyzed and biochemical tests carried out to identify the isolates to the species level [9] . In order to investigate the profiles of the presumed contaminants colonies from at least 15% plates yielding CFUs below the 105 CFU/ml thresholds were randomly selected and analyzed alongside those from UTI cases.

2.4. Antimicrobial Susceptibility Testing

Antimicrobial susceptibility testing of pure isolates was performed according to the Kirby-Bauer disc diffusion method [10] on Mueller Hinton agar (Oxoid, Ltd, England). The standard reference strains, S. aureus (ATCC-25923) and E. coli (ATCC-25922) were used as quality control organisms to ascertain antibiotic discs potency and quality of the test media. Results were interpreted based on CLSI 2016 guidelines [11] . The double disc synergy test was used to test for extended spectrum β-lactamase (ESBL) production following the CLSI (2015) guidelines. Isolates showing synergy zones between amoxicillin/clavulanic and one or more third generation cephalosporins were identified as ESBL-producers [12] Susceptibility to Cefoxitin was used for the detection of Methicillin Resistant Staphylococcus aureus-MRSA [13] .

2.5. Data Analysis

Data analysis was done using using the SAS software, version 9.3 (SAS Institute). Chi-square test was applied for P-value derivation for socio-demographic and risk factors associated with UTIs. Binary logistic regression analysis was carried out to generate the adjusted odds ratio with 95% confidence interval, an alpha of less than 0.05 (P < 0.05) was considered statistically significant.

 3. Results 3.1. Recruitment and Prevalence of UTI

A total of 210 pregnant women were recruited in the study. The overall prevalence of UTI was 15.7%. Prevalence of asymptomatic and symptomatic bacteriuria was 4.3% and 11.4% respectively.

 3.2. Social-Demographic Characteristics

Pregnant mothers in the age group of 21 - 30 years had the highest prevalence of UTI at 75.8% followed by those aged 31 - 40 years at 12.1%, below 20 years of age at 9.1% while those above the age of 40 years had the least prevalence of 3%. UTI prevalence was also high among mothers in the second trimester (60.6%) compared to third trimester (24.2%) and first trimester (15.2%). High prevalence of bacteriuria was observed among multiparous mothers (72.7%) as compared to nulliparous (27.3%). Despite these variations, there was no significant association between UTI and maternal age, parity, occupation, gestation, marital status or level of education P > 0.05, Table 1.

3.3. Lifestyle Factors

Among the lifestyle factors surveyed, mothers with multiple partners were two times more likely to develop a UTI (OR 2.45; P > 0.05) compared to those with a single partner Table 2. Those who used non-cotton undergarments were three times more likely to develop a UTI compared to those who used cotton undergarments (P = 0.001). This study also found that the frequency of changing undergarment was significantly associated with UTI, (P < 0.05). Those who changed once were 2 times likely to develop UTI compared to those who changed twice. When respondents were asked to state what causes UTI, a larger proportion (37.6%) had no idea while others indicated that women got UTI from sexual intercourse (17.6%), poor urogenital hygiene (9%), contaminated toilets (25.7%) and damp panties (10%).

3.4. Diversity of Bacterial Isolates from Urine

From the 99 UTI isolates identified, 78 (78.8%) were gram negative while 21 (21.2%) were gram positive bacteria. E. coli was the most predominant UTI isolate at 44.5% followed by K. pneumoniae (21.2%) and S. aureus (15.1%). Other organisms included P. aeroginosa, Acinetobacter spp. and Enterococcus spp. each at 6.1%. Analysis of 15% of the urine samples that would have been classified as

 References Aseel, M., Meer, F.A., Kuwari, M.A. and Ismail, M. (2011) Prevalence and Predictors of Asymptomatic Bacteriuria among Pregnant Women Attending Primary Health Care in Qatar. Qatar National Research Strategy, 2011, 1715. Schnarr, J. and Smaill, F. (2008) Asymptomatic Bacteriuria and Symptomatic Urinary Tract Infections in Pregnancy. European Journal of Clinical Investigation, 38, 50-57. Agersew, A., Feleke, M., Yitayai, S., Ketema, T., Afework, K. and Abebe, A. (2012) Bacteria Profile and Drug Susceptibility Pattern of Urinary Tract Infection in Pregnant Women at University of Gonden Teaching Hospital, Northwest Ethiopia. BMC Research Notes, 5, 197-204. <br />https://doi.org/10.1186/1756-0500-5-197 Masinde, A., Gumodoka, B., Kilonzo, A. and Mshana, S.E. (2009) Prevalence of urinary Tract Infection among Pregnant Women at Bugando Medical Centre, Mwanza, Tanzania. Tanzania Journal of Health Research, 11, 154-159. <br />https://doi.org/10.4314/thrb.v11i3.47704 Delzell Jr., J.E. and Lefevre, M.L. (2000) Urinary Tract Infections during Pregnancy. American Family Physician, 61, 713-721. Gilbert, N.M., O’brien, V.P., Hultgren, S., Macones, G., Lewis, W.G. and Lewis, A.L. (2013) Urinary Tract Infection as a Preventable Cause of Pregnancy Complications: Opportunities, Challenges, and a Global Call to Action. Global Advances in Health and Medicine, 2, 59-69. <br />https://doi.org/10.7453/gahmj.2013.061 Kose, Y., Abasiyanik, M.F. and Salih, B.A. (2007) Antibiotic Resistance Rates of Escherichia Coli Urinary Tract Isolates in Rize Province, Turkey. The Journal of Infection in Developing Countries, 1, 147-150. Nicolle, L.E., Bradley, S., Colgan, R., Rice, J.C., Schaeffer, A. and Hooton, T.M. (2005) Infectious Diseases Society of America Guidelines for the Diagnosis and Treatment of Asymptomatic Bacteriuria in Adults. Clinical Infectious Diseases, 40, 643-54. <br />https://doi.org/10.1086/427507 Monica, C. (2000) Biochemical Tests to Identify Bacteria. Cambridge University Press. Bauer, A.W., Kirby, W.M.M., Sherris, J.C. and Turck, M. (1996) Antibiotic Susceptibility Testing by a Standardized Single Disk Method. American Journal of Clinical Pathology, 45, 493-496. Clinical Laboratory Standard Institute (CLSI) (2016) Performance Standards for Antimicrobial Susceptibility Testing; Twenty-Sixth Informational Supplement. Vol. CLSI Docum, No. Wayne, PA. Rawat, D. and Nair, D. (2010) Extended-Spectrum β-Lactamases in Gram Negative Bacteria. Journal of Global Infectious Diseases, 2, 263-274. <br />https://doi.org/10.4103/0974-777X.68531 Jain, A., Agarwal, A. and Verma, R.K. (2008) Cefoxitin Disc Diffusion Test for Detection of Meticillin-Resistant Staphylococci. Journal of Medical Microbiology, 57, 957-961. <br />https://doi.org/10.1099/jmm.0.47152-0 Andabati, G. and Byamugisha, J. (2010) Microbial Aetiology and Sensitivity of Asymptomatic Bacteriuria among Ante-Natal Mothers in Mulago Hospital, Uganda. African Health Sciences, 10, 349-352. Dimetry, S.R., El-tokhy, H.M., Abdo, N.M., Ebrahim, M.A. and Eissa, M. (2007) Urinary Tract Infection and Adverse Outcome of Pregnancy Clinical Pathology Department. The Journal of the Egyptian Public Health Association, 82, 203-218. Griebling, T.L. (2007) Urinary Tract Infection in Women. In: Litwin, M.S. and Saigal, C.S., Eds., Urologic Diseases in America, US Department of Health and Human Services, Public Health Service, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, US Government Printing Office: NIH Publication, Washington DC, 589-619. Hamdan, H.Z., Ziad, A.H.M., Ali, S.K. and Adam, I. (2011) Epidemiology of Urinary Tract Infections and Antibiotics Sensitivity among Pregnant Women at Khartoum North Hospital. Annals of Clinical Microbiology and Antimicrobials, 10, 2. <br />https://doi.org/10.1186/1476-0711-10-2 Guinto, V.T., De Guia, B., Festin, M.R. and Dowswell, T. (2010) Different Antibiotic Regimens for Treating Asymptomatic Bacteriuria in Pregnancy. The Cochrane Database of Systematic Reviews, No. 9, CD007855. Ayoyi, A.O., Kikuvi, G., Bii, C. and Kariuki, S. (2017) Prevalence, Aetiology and Antibiotic Sensitivity Profile of Asymptomatic Bacteriuria Isolates from Pregnant Women in Selected Antenatal Clinic from Nairobi, Kenya. Pan African Medical Journal, 26, 1-12. <br />https://doi.org/10.11604/pamj.2017.26.41.10975 Oladeinde, B.H., Omoregie, R. and Oladeinde, O.B. (2015) Asymptomatic Urinary Tract Infection among Pregnant Women Receiving Ante-Natal Care in a Traditional Birth Home in Benin City, Nigeria. Ethiopian Journal of Health Sciences, 15, 3-8. Kariuki, S., et al. (2007) Escherichia Coli from Community-Acquired Urinary Tract Infections Resistant to Fluoroquinolones and Extended-Spectrum Beta-Lactams. The Journal of Infection in Developing Countries, 1, 257-262.