The Bacterial Isolates and Plasmid Profile of Extended Spectrum Beta-Lactamases Producers Causing Urinary Tract Infection among Pregnant Women in Uyo, Nigeria

Abstract

Background: Extended spectrum beta-lactamases (ESBLs) are enzymes that compromise the efficacy of all beta-lactams and are spread by plasmids. They are of public health importance the world over; however, in Nigeria in general and Uyo in particular, tests for their detection are not routinely done in hospital laboratories despite increase in treatment failures observed for common clinical conditions like urinary tract infection. Objective: To isolate ESBLs producing uropathogens and the plasmid underlying their resistance to antibiotics. Materials and Methods: Three hundred urine specimens (n = 300) were collected from pregnant women attending antenatal clinics at St. Lukes Hospital, Anua, cultured and incubated according to accepted standard. Identification of isolates was done using Microbact 24E (Oxoid, UK) system. The predominant bacterial pathogens were Escherichia coli (42%) followed by Klebsiella pneumonia (21%), Klebsiella oxytoca (12%), Citrobacter spp. (5%), Proteus mirabilis (7%), Enterobacter spp. (12%) and Acinetobacter baumanii (1%). The isolated bacteria were tested for their antibiotic susceptibility using Clinical Laboratory Standard Institute (CLSI) recommended disc diffusion method. A Double Disk Synergy Test (DDST) and Phenotypic Disk Confirmatory Test (PDCT) were performed to determine ESBL production. Chromagar ESBL was also used to test for the presence of ESBL producing isolates. The plasmid content of ESBL producing isolates and their participation in drug resistance were investigated. Results: Of the 80 bacterial isolates causing urinary tract infection in these women, the ESBL producers were found to be 16 (20%). Out of these 16 ESBL producing urogenital isolates Klebsiella pneumonia (8, 50%) was the most prevalent. Others include Escherichia coli (38%), Klebsiella oxytoca (6%) and Enterobacter cloacae (6). Plasmid content of ESBL producing isolates was found to be 87.5%. Conclusion: The Extended Spectrum Beta-lactamase producing uropathogens mainly of plasmid origin are increasingly responsible for the cause of community acquired urinary tract infections in pregnant women in Uyo.

Correlation of Urinary Tract Infection Pathogens, Antibiogram and Age Group in Pregnant Women

“…Many reports showed that UTI is common in patients with different symptoms [14]. However, our concern in this study is to focus on pregnant women at different age group were they believed to have highest infection rate [2,14]. Due to the fact that untreated UTI in pregnancy can increases the risks of morbidity, and mortality to pregnant women and infant [17], keeping in mind that estimated 40 percent of women reported to have UTI some time in their lives [15], and by nature women are more susceptible to UTI because accessibility of organism to invade urethra and bladder easier than men [18].…”

“…This is partially due to the short and wider female urethra and its proximity to anus. Bacteria from the rectum can easily travel up the urethra and cause infections [2,19,20]. Other factors reported to increase rate of infection are pregnancy and sexual intercourse [19], due to vaginal trauma which enhance access of bacteria to urethral into bladder [2,17,19].…”

“…Many studies reported the significance of UTI during pregnancy although pregnancy does not cause UTI [3][4][5][6], however, the complexity of urinary tract system and changes during pregnancy account for susceptibility to infection [3][4][5]7,8] Urinary tract infections have been reported in all age groups and can occur in both sexes [2,9] and pregnant women are not an exception [5,6]. UTI is a serious health problem worldwide affecting millions of people each year and the leading cause of Gram-negative bacteria [9,10].…”

“…Urinary Tract Infections (UTIs) is an infection caused by the presence and growth of microorganism anywhere in the urinary tract and is perhaps the single commonest bacterial infection of mankind [1,2]. Many studies reported the significance of UTI during pregnancy although pregnancy does not cause UTI [3][4][5][6], however, the complexity of urinary tract system and changes during pregnancy account for susceptibility to infection [3][4][5]7,8] Urinary tract infections have been reported in all age groups and can occur in both sexes [2,9] and pregnant women are not an exception [5,6].…”

“…UTI is a serious health problem worldwide affecting millions of people each year and the leading cause of Gram-negative bacteria [9,10]. Over eight million cases of UTI annually were reported and more than one million were hospitalized, for an overall annual cost more than $1 billion [10][11][12], classifying hospital and antenatal clinic in the lead as source of UTI pathogens [2,13] and responsible for 35% of the cases where bacteraemia was the most common cause in hospitalized patients [14][15][16] Diagnosis of UTI causing organism is the major work load in medical laboratories where Escherichia coli reveal the highest predominate rate although, other reports showed that the causative organism of UTI is changing over the year and other microorganism were responsible for infection [13,14]. Many reports showed that UTI is common in patients with different symptoms [14].…”