Background: Fluoroquinolones (FQs) are potential drugs that inhibit DNA synthesis and are used in the treatment of multidrug-resistant tuberculosis (TB) and short-term anti-TB regimens. In recent years, a high proportion of FQ resistance has been observed in Mycobacterium tuberculosis isolates. The development of FQ resistance in multidrug-resistant TB negatively impacts patient treatment outcome and is a serious threat to control of TB. Methods: The study included a total of 562 samples from patients with pulmonary TB that had been on anti-tuberculosis therapy. MTBDRsl assays were performed for the molecular detection of mutations. Sequence analysis was performed for the characterization and mutational profiling of FQ-resistant isolates. Results: FQ resistance was observed in 104 samples (18.5%), most of which were previously treated and treatment failure cases. A total of 102 isolates had mutations in DNA gyrase subunit A (gyrA), while mutations in gyrB were observed in only two isolates. Mutational analysis revealed that the mutations mostly alter codons 94 (replacing aspartic acid with glycine, D94G) and 90 (replacing alanine with valine, A90V). In MDR and treatment failure cases, resistance to FQs was most commonly associated with the D94G mutation. In contract, a high proportion of A90V mutations were observed in isolates that were newly diagnosed. Conclusion: The findings suggest that genotypic assays for FQ resistance should be carried out at the time of initial diagnosis, before starting treatment, in order to rule out mutations that impact the potential use of FQs in treatment and to control drug resistance.

Background: Urinary tract infection (UTI) is deemed the most prevalent infectious disease in that it has now touched the overall incidence of 18/1000 persons per year in the general population. Objectives: This study sought to determine the characteristics of isolates from patients with UTI and their susceptibility to commonly used antibiotics in Punjab, Pakistan. Patients and Methods: Totally, 1429 urine samples were analyzed from UTI patients for the isolation of uropathogens at Chughtai’s Lahore Lab, Lahore, Pakistan, during a period of 14 months. The antimicrobial susceptibility test was performed via the disc diffusion method for the isolates obtained from 392 (26%) positive cultures. Results: The highest percentage (67%) of isolates was from females in comparison to males (33%). The frequency of Escherichia coli was the highest (62%) in culture-positive urine samples, followed by E. faecalis (15%), Candida (14%), Pseudomonas (6%), Klebsiella spp. (1%), Proteus (1%), and Staphylococcus aureus (1%). E. coli was highly resistant to antimicrobial drugs, viz. cephalexin (95%), cephradine (95%), pipemidic acid (92%), amikacin (91%), and nalidixic acid (91%). Most of the routine β-lactam antibiotics like amoxicillin/clavulanic acid, ampicillin, and aztreonam were also ineffective against E. coli, with resistance rates of 84%, 84%, and 72%, correspondingly. This pathogen showed maximum susceptibility (97%) against three drugs, namely imipenem, meropenem, and cefoperazone. Piperacillin and fosfomycin also provided significant results against E. coli with respective susceptibility rates of 96% and 90%. Conclusions: Our results showed that broad-spectrum antibiotics such as imipenem, meropenem, fosfomycin, cefoperazone/sulbactam, and vancomycin would be the first line and the most effective drugs for the empirical treatment of urinary tract pathogens due to their higher resistance rates against other drugs like cephalexin, cephradine, ciprofloxacin, levofloxacin, and norfloxacin. Keywords: Urinary Tract Infections; Escherichia coli; Antimicrobial Drugs

The drug resistant Acinetobacter strains are important causes of nosocomial infections that are difficult to control and treat. This study aimed to determine the antimicrobial susceptibility patterns of Acinetobacter strains isolated from different clinical specimens obtained from patients belonging to different age groups. In total, 716 non-duplicate Acinetobacter isolates were collected from the infected patients admitted to tertiary-care hospitals at Lahore, Pakistan, over a period of 28 months. The Acinetobacter isolates were identified using API 20E, and antimicrobial susceptibility testing was performed and interpreted according to Clinical and Laboratory Standards Institute (CLSI) guidelines. The isolation rate of Acinetobacter was high from the respiratory specimens, followed by wound samples. Antibiotic susceptibility analyses of the isolates revealed that the resistance to cefotaxime and ceftazidime was the most common, in 710 (99.2%) specimens each, followed by the resistance to gentamicin in 670 (93.6%) isolates, and to imipenem in 651 (90.9%) isolates. However, almost all isolates were susceptible to tigecycline, colistin, and polymyxin B. The present study showed the alarming trends of resistance of Acinetobacter strains isolated from clinical specimens to the various classes of antimicrobials. The improvement of microbiological techniques for earlier and more accurate identification of bacteria is necessary for the selection of appropriate treatments.

Background: Keeping in mind the commercial application of polygalacturonase (PG) in juice and beverages industry, bacterial strains were isolated from rotten fruits and vegetables to screen for competent producers of PG. Objectives: In this study, the plate method was used for preliminary screening of polygalacturonase-producing bacteria, while the Dinitrosalicylic Acid (DNS) method was used for quantifications of PG. Materials and Methods: Biochemically-identified polygalacturonase-producing Bacillus and Pseudomonas species were further characterized by molecular markers. The genetic diversity among these selected strains was analyzed by investigating microsatellite distribution in their genome. Out of 110 strains, 17 competent strains of Bacillus and eight strains of Pseudomonas were selected, identified and confirmed biochemically. Selected strains were characterized by 16S rRNA sequencing and data was submitted to the national center for biotechnology information (NCBI) website for accession numbers. Results: Among the Bacillus, Bacillusvallismortis (JQ990307) isolated from mango was the most competent producer of PG; producing up to 4.4 U/µL. Amongst Pseudomonas, Pseudomonasaeruginosa (JQ990314) isolated from oranges was the most competent PG producer equivalent to B. vallismortis (JQ990307). To determine genetic diversity of different strains of Pseudomonas and Bacillus varying in PG production, fingerprinting was done on the basis of Simple Sequence Repeats (SSR) or microsatellites. The data was analyzed and a phylogenetic tree was constructed using the Minitab 3 software for comparison of bacterial isolates producing different concentrations of PG. Fingerprinting showed that presence or absence of certain microsatellites correlated with the ability of PG production. Conclusions: Bacteria from biological waste were competent producers of PG and must be used on an industrial scale to cope with the demand of PG in the food industry. Keywords: Polygalacturonase; Phylogenetic DNA; Dinitrosalicylic Acid (DNS) Method; Bacillus spp.; Pseudomonas spp.

Keywords: Community acquired MRSA; Hospital acquired MRSA; Central venous cateter; Antimicrobial resistance; Biofilm and adhesion genes

Introduction: The spread of carbapenem-resistant Acinetobacter baumannii (CRAB) is difficult to control especially in the hospitals due to the successful mobilization and evolution of the genetic elements harboring the resistant determinants. The study was conducted to examine the distribution of aminoglycosides, tetracycline, and sulfonamide-resistant determinants among CRAB isolates that carry the blaOXA-23 gene. Methodology: For a total of 160 CRAB strains isolated at tertiary care hospitals of Pakistan that mainly carried blaOXA-23 gene were included in the study to evaluate the assortment of antibiotic resistance genes. Results: The susceptibility rates of CRAB for other than beta-lactam drugs were 2.5% for both ciprofloxacin and aminoglycosides and 18% and 25% for sulfonamides and tetracyclines, respectively. Polymyxin B (MIC90, 1 g/mL) Colistin (MIC90, 1 g/mL) and Tigecycline (MIC90, 2 g/mL) were most active against these extensively drug-resistant CRAB isolates. The isolates were found to possess various genes mainly the tetB and sul2 for tetracycline and sulfonamide but the genes conferring resistance to aminoglycosides were varied with various combinations. Conclusion: Despite the CRAB clones containing blaOXA-23 have been previously reported in Pakistani hospitals, the screening of genetic determinants responsible for other antimicrobial agents is crucial for developing an effective surveillance and mitigation system for infection management.