Background and Objectives: Moraxella catarrhalis is considered as an emerging pathogen and a new nosocomial infection agent. This study was conducted to isolate and identify M. catarrhalis from clinical samples (respiratory tracts) and assess them for antimicrobial susceptibility patterns.
      Methods: In total, 280 samples were collected from patients with respiratory tract infection, and 120 samples were obtained from healthy individuals in the control group. The isolates were identified by phenotyping and genotyping methods, and their antibiotic susceptibility was  evaluated using disk diffusion methods. The presence of β-lactamase and efflux pump activity were specified via phenotypic methods. Finally, Bro and acrA genes in the isolates were detected by PCR technique.
      Results: The frequency of this bacterium was 9.64% (27 out of 280) in patients with respiratory tract infection and 4.16% (5 out of 120) in the control group. Although the isolates were resistant to penicillin, they had various responses against other antibiotics. The results obtained from molecular method showed that 90.6% and 84.3% of the isolates possessed Bro and acrA genes, respectively. There was a significant relationship (P<0.05) between the presence of Bro and acrA genes and antibacterial resistance to ampicillin, amoxicillin, cefazolin, cefuroxime, and chloramphenicol.
      Conclusion: Our findings confirmed the existence of M. catarrhalis in patients with respiratory diseases and the high prevalence of antibiotic resistant genes in M. catarrhalis isolates. Therefore, timely diagnosis and successful treatment can play important roles in preventing their spread.

Pasteurella species are one of the most common pathogenic bacteria in domestic animals, and they are seen more in people with weak immune systems. This research aims to investigate a case of a patient with multiple sclerosis from whose sputum Pasteurella multocida (P. multocida) was isolated. The patient was a 28-year-old man with multiple sclerosis who had persistent coughs due to food being stuck in his throat. The patient was a 28-year-old man with multiple sclerosis who had persistent coughs due to food being stuck in his throat. The primary diagnosis was pneumonia hydropneumothorax and complete collapse of the left lung. The patient's sputum culture after the first visit to the hospital was positive for P. multocida, which was not found in a second culture. In the subsequent cultures of the patient, Acinetobacter, Klebsiella, Pseudomonas aeruginosa (P. aeruginosa), and Citrobacter were found, which had extensive drug resistance to all antibiotics. In the secondary computerized tomography (CT) scan, mild pleural effusion on the left side, pneumothorax, and complete collapse with bronchiectasis was seen. Despite the treatments, the patient finally died of cardiac arrest and bradycardia. Infection with P. multocida was found in a patient with multiple sclerosis. Also, hospital-acquired infections with drug resistance caused by the weakness of the patient's system appeared in the patient who was hospitalized in the intensive care unit (ICU), and finally, the patient died. According to antibiotic patterns, the best antibiotic to which the bacteria is sensitive can be considered the primary treatment to avoid irrational antibiotic prescriptions.
 

Background: Acinetobacter baumannii (A. baumannii) has emerged as the predominant etiological agent responsible for bloodstream infections among hospitalized patients. The objective of this study was to evaluate antibiotic resistance in A. baumannii isolates identified from blood cultures.
Methods: A retrospective cohort evaluation was conducted on 117 A. baumannii isolates obtained from blood cultures collected between 2018 and 2019 at the Microbiology Laboratory of Tokat Gaziosmanpaşa University Hospital (Türkiye). The blood culture samples were incubated using the BACT-ALERT 3D system (bioMérieux, Durham, NC, USA). Microorganism identification and antibiotic susceptibility testing were performed using the VITEK 2 (bioMérieux, France) automated system.
Results: Of the 117 samples, 59.8% were obtained from males and 40.2% from females. A total of 90.6% of blood culture samples were collected from the intensive care unit, and 88.9% of isolates were identified as multidrug-resistant (MDR). The highest resistance was observed against meropenem (99.1%), while the lowest resistance was noted for colistin (17.1%) and tigecycline (27.3%). Resistance to amikacin was 74.4%, while resistance levels to gentamicin, tobramycin, cefoxitin, and cefotaxime were within the range of 80–90%. Resistance to imipenem, amoxicillin/clavulanic acid, ampicillin/sulbactam, ceftazidime, cefepime, ciprofloxacin, levofloxacin, meropenem, and ertapenem exceeded 90%.
Conclusion: The increasing number of MDR A. baumannii isolates poses a significant threat to all hospitalized patients. However, colistin and tigecycline remain preferable options for the treatment of MDR A. baumannii infections. Considering the increasing prevalence of MDR A. baumannii isolates, periodic analysis of epidemiological data in healthcare centers is important for managing resistance to colistin and tigecycline.
 

Background: Tigecycline susceptibility testing and reporting remain enigmatic due to the lack of established guidelines. Disc diffusion, as a method of performing susceptibility testing, is more widely accepted worldwide due to its ease of use. Limited published literature is available from India on the utility of this method, especially in a cancer care setting. Hence, this study was conducted to evaluate the performance characteristics of disc diffusion by comparing its results with those of the VITEK-2 COMPACT, considering the latter as the standard.
Methods: Disc diffusion was performed using Kirby-Bauer’s method on Mueller-Hinton agar with a HiMedia 15 mcg TGC disc, following FDA and EUCAST breakpoints. According to CLSI criteria, disc diffusion breakpoints can be considered acceptable when categorical agreement is ≥ 90%, the very major error is ≤ 1.5%, and the major error is ≤ 3%.
Results: Using Cohen’s kappa coefficient, the kappa value was 0.328, with a p-value of <0.05. The agreement percentage observed was 60.84%. Two strains reported as resistant by VITEK-2 COMPACT were misclassified as sensitive by disc diffusion, resulting in a very major error rate of 0.76%. A major error rate of 9.5% and a minor error rate of 27.7% were noted, as 25 strains reported as susceptible were identified as resistant.
Conclusion: Since poor agreement was observed, exceeding the acceptable performance rate, the disc diffusion method was unacceptable according to CLSI criteria. There is a gap in uniformity and a lack of streamlined, harmonized TST, which might become an alarming cause for concern.