Determination of multi-drug resistance (MDR) profile of isolated Gram-positive and Gram-negative bacteria from clinical pus sample in Bangladesh
Authors: Nobel Fahim Alam , Ahammad Hasib , Saha Sumita Rani , Nashra Aanan , Zahan Yeasmin , Kamruzzaman Mohammad , Babu Golap , Amin Mohammed Badrul , Uddin Mohammad Khaja Mafij , Islam Mohammod Johirul 
Published: April 2023

Abstract
Introduction: Antimicrobial resistance is becoming a very concerning and challenging issue on a global scale nowadays. The rapid spread of drug-resistant pathogenic bacteria is a serious public health concern in both developed and developing countries, including Bangladesh. This study aimed to determine the prevalence of antibiotic-resistant pathogenic bacteria in pus samples and their multi-drug resistance (MDR) rate.
Methods: A total of 891 pus positive samples were collected from the Lab Zone and Hormone center in Tangail, Bangladesh between January 2018 to March 2022.The standard microbiology culture method was used to process the samples, and the resulting bacterial isolates were confirmed by biochemical tests and gram staining to classify bacterial species into two large groups. Antimicrobial susceptibility tests were performed for the identified bacterial isolates using standard disk diffusion method.
Results: Of the 891 samples collected, 71.83% (n=640) were male, and 28.17% (n=251) were female patients. Gram-negative bacteria were found in 70.37% (n=627) of the samples, while 29.63% were Gram-negative bacteria. Most of the isolates showed resistant to 3 or ≥3 classes of antibiotics and termed as Multi Drug Resistant (MDR) isolates. Among the Gram-negative bacterial isolates, Pseudomonas spp. was the most predominant 58.69% (n = 368), followed by Proteus spp. 15.15% (n = 95), and E. coli 14.83% (n = 93), Klebsiella spp. 10.21% (n = 64), Acinetobacter spp. 0.96% (n=6), Enterobacter 0.16% (n=1). On the other hand, in Gram-positive bacterial isolates, Enterococcus faecalis belonging to 39.02% (n=103) which is the most predominant followed by Staphylococcus aureus 30.68% (n=81), Staphylococcusspp. 29.16% (n=77), and Streptococcus spp. 1.14% (n=3). E. coli showed the highest resistance to Amoxicillin (AMC) and Acinetobacter showed the maximum resistance upon sixteen out of twenty antibiotics. These two bacteria displayed the most multidrug resistance (MDR) demonstrating E. coli (n=32, 34.41%) to eight different antibiotic classes, Acinetobacter (n=6,100%) to ten different antibiotic classes. Enterococcus faecalis was completely resistant to eight antibiotics out of twenty and Streptococcus spp displayed the highest resistance to cephradine (CH), cefixime (CFM), and cefuroxime (CXM). For a demonstration of Gram-positive bacterial isolates, Enterococcus faecalis (n=89, 86.41%) showed the highest resistance against eight different classes of antibiotics.
Conclusion This study found a higher prevalence of MDR bacteria in pus samples which highlights empirical treatment should be followed judiciously. The study will also help doctors to make more informed decisions when selecting an antibiotic for the empirical treatment of various bacterial illnesses, as well as reduce community antibiotic abuse and overuse.