Antibacterial resistance patterns of bacteria isolated from clinical specimens at Uttara IbnSina Diagnostic Centre, Dhaka

Nowadays, antibiotic resistance is a global public health threat. Bangladesh is accelerated to this owing to its sub-standards healthcare along with the self-medication and overuse of antibiotics. The study aimed to assess patterns of antibacterial resistance in the clinical samples. The study was carried out at Ibn Sina Diagnostic and Consultation Center Uttara, Dhaka, from January to December 2019. All cultures and antimicrobial susceptibility test results of patients were extracted from laboratory records, using a semi-structured checklist. Data were analyzed using Microsoft Excel and SPSS version 20.0. To ensure confidentiality coding was used instead of the patient’s identity. A total of 925 culture-positive results were analyzed, of which blood 620(65.0%) and urine 297(32.1%) samples were commonly diagnosed. The most frequently isolated bacterial were Salmonella spp. [601(65%)], Escherichia coli [244(26.4%)] and Klebsiella spp. [57(6.16%)]. The majority of the patients were females [540(58.4%)]. E. coli was found to be highly sensitive (>80%) to nitrofurantoin, meropenem, amikacin, amoxiclav, and imipenem; simultaneously, resistant (>45%) to cefixime, cephalexin, piperacillin, aztreonam, ampicillin, cefuroxime, and ciprofloxacin. S. typhi and S. paratyphi were sensitive (>80%) for cefepime, ceftriaxone, imipenem, tetracycline, cefixime, ceftazidime, cephalexin, cotrimoxazole, aztreonam, cefuroxime, and amoxiclav; concurrently, above 80% resistance for ciprofloxacin, azithromycin, gentamycin, and ampicillin. Overall, most of the isolates showed a significant rising rate of microbial resistance to ciprofloxacin, azithromycin, piperacillin, cephalexin, gentamycin, and ampicillin. The study findings revealed gradually rising rates of antibiotic resistance to commonly prescribed antibiotics. The study suggested the prescribers should be avoided overuse and irrational use of drugs to reduce antimicrobial resistance.


INTRODUCTION
Antibiotic resistance is a well-known public health concern at the community, national and global levels (Nordberg et al., 2004). Decreasing the effectiveness of antibiotics in treating bacterial common infections and a decline in the new drug development rate is a concerning issue (Kandelaki et al., 2015;Luepke and Mohr, 2017;Spellberg et al., 2004). Antibiotic resistance poses a significant risk of mortality and economic burden worldwide (Ahmed et al., 2019). The causes of antibiotic resistance are complex which include enzymatic degradation of antibacterial drugs, alteration of bacterial proteins that are antimicrobial targets, and changes in membrane permeability to antibiotics (Kandelaki et al., 2015). The low-and middle-income countries are more affected because of extensive misuse of antibiotics, nonhuman antibiotic use, poor quality of drugs, insufficient surveillance, and other factors associated with poor healthcare standards, malnutrition, chronic and repeated infection, unaffordability of more effective and costly drugs (Ayukekbong et al., 2017;Sosa et al., 2010). In 2014, the World Health Organization (WHO) reported on global surveillance of antimicrobial resistance, significant gaps prevail in surveillance, absence of standards methodology, data sharing and coordination. WHO identified the major gaps in the South-East Asia Region, the African Region, and the Eastern Mediterranean region (WHO, 2014).
Bangladesh is one of the South-East Asian developing countries and has a high rate of antibiotic resistance which poses a regional and global concern (Rahman and Huda, 2014). Enteric fever caused by salmonella spp. has been detected among children aged <5 years of age than the age group ≥5 years in the South-East Asian especially in India and Bangladesh. Though, there are no valid data regarding paratyphoid fever in Bangladesh (Naheed et al., 2010). Therapeutic failures in Bangladesh are not uncommon. Multiple studies have demonstrated irrational antibiotic prescribing by physicians, selfmedication habits of patients, and indiscriminate use of antibiotics in agriculture and farming in different segments of the country (Biswas et al., 2014a;Biswas et al., 2014b;Sutradhar et al., 2014). Therefore, the prevalence of antibiotic resistance in Bangladesh is high, but no attempts have been undertaken to alleviate it. This study aims to serve as a reference for future works and to guide policymakers and prescribers to adopt the best strategy to lower the extent of antibiotic resistance as well as combat the problems following the expanding resistance.

Study design and setting
This retrospective cross-sectional study was executed from January to December 2019 at IbnSina Diagnostic and Consultation Center Uttara, Dhaka. The sample was collected by using a sterile ascetic technique. A total of 925 culture-positive test result samples were analyzed. All cultures and antimicrobial susceptibility test results of patients were extracted from laboratory records notebook by using a semi-structured checklist. The sample-set included blood, urine, stool and sputum samples as well as wound swabs.

Bacterial isolates and identification
All of the received clinical specimens were initially cultured and subcultures into brain heart infusion, blood agar, Salmonella-Shigella agar, Chocolate agar and Mac-Conkey agar as per need, and after overnight incubation at 37°C, the bacteria identification was completed by gram staining as well as standard biochemical tests (catalase, coagulase, oxidase). This was done by subculturing on mediums such as triple sugar iron agar (TSI), SIM medium, and Simmons' citrate agar.

Statistical analysis
The data were entered into Microsoft Excel and analyzed by SPSS version 20. The results were presented as descriptive statistics in terms of relative frequency, percentage, mean ± standard deviation (SD) and to summarize patients' attributes and other related information.

Ethical considerations
Ethical approval was obtained from the Institutional Review Board. Administrative authorization for this study was obtained from the Branch Manager of the Diagnostic Center. The researchers highly consider the human right of the participants. To ensure the confidentiality coding method was used instead of other identifiers of the patients.

DISCUSSION
Bacterial infections are the predominant problem in developing countries like Bangladesh where water, sanitation, and hygiene (WASH) continue to be below international standard. The shortage of reliable microbial and antimicrobial data is also a problem in managing the physicians treating patients with a bacterial infection before the appropriate treatment is applied to get the best outcome (Tjaniadi et al., 2003). The major cause behind antibiotic resistance makes the bacteria to be smart. However, in Bangladesh, prescribers usually diagnose microbial infection based on clinical finding and choose antimicrobial drugs on an experiential basis (Faiz and Rahman, 2004), which critically distresses the sensitivity pattern of microorganisms. Besides, the unwillingness of the policymakers and officials to sanction law to overcome insufficient guidelines and instruction to control antimicrobial prescription and administration leads to the deteriorating of the circumstance.

Conclusion
The present study revealed that E. coli, salmonella typhi, and salmonella paratypi were the most frequently isolated bacterial in the clinical samples. The majority of the isolated bacteria showed certain levels of antimicrobial resistance to commonly recommended drugs like ampicillin, norfloxacin, ciprofloxacin, azithromycin, cephalexin, piperacillin and cotrimoxazole. However, strict policy and appropriate use of antibiotics can assuage the burden of antimicrobial resistance. It is highly suggested to perform antimicrobial susceptibility testing before the administration of antibiotics and ensure the rational use of drugs to reduce antibiotic resistance.