Achromobacter Spp.: A retrospective review of rare and emerging pathogen

Background: Achromobacter spp. is a rare nosocomial pathogen known to cause many serious infections like bloodstream infection, osteomyelitis, meningitis, urinary tract infections, corneal ulceration, peritonitis, and endocarditis. Materials and Methods: In this study, we retrospectively analyzed all the bacteriological sample records from the bacteriology database from January 2021 to December 2021 to determine the prevalence of Achromobacter spp. Result: Nine patients with Achromobacter xylosoxidans causing bacterial infection were identified, from whom five blood samples, two pus, one respiratory sample, one central venous pressure (CVP), and one cerebrospinal fluid were found positive for Achromobacter spp., among whom one was a 6-year-old patient having the same organism from two different body sites—CVP line and cerebrospinal fluid. Five patients had coinfection with another organism, whereas acute kidney injury was the most common comorbidity. Conclusion: In our single-center experience, approximately 50% of the cases with Achromobacter denitrificans bacteremia suffered from chronic kidney disease and had a history of antibiotic therapy, hospitalization, and the presence of devices. Active research on rising trends of Achromobacter spp. needs to be promoted.

Prevalence, outcome and risk factor associated with vancomycin-resistant Enterococcus faecalis and Enterococcus faecium at a Tertiary Care Hospital in Northern India.

Purpose: To determine the prevalence, genotype, risk factors and mortality in patients having vancomycin-resistant Enterococcus faecalis (VR E. faecalis) and Enterococcus faecium (VR E. faecium) infection or colonisation. Materials and Methods: A total of 1488 clinical isolates of E. faecalis and E. faecium were tested for vancomycin resistance by phenotypic (disk diffusion, E-test and broth micro-dilution test) and genotypic polymerase chain reaction methods. Records of all 1488 patients who had E. faecalis or E. faecium infection or colonisation were reviewed for the identification of host, hospital and medication related risk factors associated with VR E. faecalis and VR E. faecium. Results: Of 1488 isolates, 118 (7.9%) were vancomycin-resistant and their distributions were as follows: E. faecalis =72 (61%) and E. faecium =46 (39%). All 118 vancomycin-resistant isolates were vanA genotype (minimum inhibitory concentration [MIC] to vancomycin ≥64 μg/ml and MIC to teicoplanin ≥32 μg/ml) and none of the isolates was vanB genotype. Multivariate logistic regression analysis identified ventilator support and hospital stay for ≥48 h as independent risk factors associated with VR E. faecalis and VR E. faecium infection or colonisation. Hospital stay ≥48 h was the only independent risk factor for mortality in patients infected with vancomycin-resistant enterococci. Conclusions: Strategies to limit the nosocomial infection especially in patients on ventilator support can reduce VRE incidence and related mortality.

Corynebacterium striatum: An emerging nosocomial pathogen in a case of laryngeal carcinoma.

Corynebacterium striatum is an emerging nosocomial pathogen associated with wound infections, pneumonia and meningitis. It is also a multidrug-resistant pathogen causing high morbidity. This is a report of an unusual case of wound infection in a patient with laryngeal carcinoma. Accurate diagnosis of the infection and prompt management helped in a favourable outcome for the patient. This case highlights the role of C. striatum as an important nosocomial pathogen in immunocompromised patients.

Analysis of carbapenem-resistant Acinetobacter from a tertiary care setting in North India.

Multidrug-resistant (MDR) Acinetobacter baumannii is a worldwide concern as cause of serious nosocomial infections. We analysed 140 non-duplicate Acinetobacter sp. isolates from hospitalised patients in a tertiary care centre; 87% were MDR and 20% (28/140) meropenem resistant. Metallo-β-lactamase was produced by 16 of these, detected by ethylene-diamine-tetra-acetic acid disc synergy test. AmpC β-lactamase and efflux pump were present in 17 and 4 of the meropenem-resistant Acinetobacter, respectively. 9/16 MBL-positive isolates carried genes for carbapenem resistance as shown by polymerase chain reaction.

Monocationic surfactant induced ultra structural changes in antibiotic resistant Escherichia coli.

Background & objectives: Cetrimide is a monocationic surfactant, commonly used for disinfection of hospital floors, equipments, for cleansing of burns and wounds, hand wash, etc. We evaluated whether antibiotic resistant (AR) Escherichia coli isolates from hospital settings (nosocomial pathogens) show any evidence of significant reduction in their susceptibility to cetrimide. Also the response of AR E. coli (nosocomial pathogens) to the action of cetrimide was assessed by studying the ultra structural changes induced using transmission electron microscopy (TEM). Methods: A total of 165 clinical samples were screened for isolation of E. coli. Eighty two (49.6%) samples were positive for E. coli. Antibiotic susceptibility testing of E. coli isolates was carried out by Kirby Bauer method to isolate AR E. coli. The randomly selected AR E. coli isolate was treated with different concentrations of cetrimide and minimum inhibitory concentration (MIC) of cetrimide was determined by broth micro dilution method. This same isolate was used for performing time kill assay and TEM study. Results: The test E. coli isolate showed resistance to 12 different antibiotics. The MIC of cetrimide against AR E. coli was 312.5 μg/ml. The ultra cellular structural changes in cetrimide treated AR E. coli revealed vacuole formation, disaxilization of nuclear material, loss of cytoplasmic granularity, bleb formation and cell lysis. Conclusion: Ultra structural changes induced by the action of cetrimide revealed cell damaging changes in the AR E. coli to be dose and time dependent. The results showed that antibiotic resistance does not alter any change in susceptibility of E. coli to cetrimide, which was found to be still an effective disinfectant against a nosocomial pathogen E. coli.

Evaluation of In Vitro Bactericidal Activity of Disinfectants against Major Nosocomial Pathogens / 병원감염관리

BACKGROUND: Disinfectants play an important role in preventing nosocomial infection. But the misuse of disinfectants may lead to waste money and decrease the effectiveness of disinfectants by emergence of resistant-bacteria. We studied to evaluate the in vitro bactericidal activity of various disinfectants used in the hospital against major nosocomial pathogens. METHOD: Disinfectants studied were chlorhexidine (0.05%, 0.1 %, 02%, 0.5%, 1%), hibicol 0.5%, alkyl diaminoethyl glycine (0.01 %. 0.05%, 0.1%. 0.5%, 1%), benzalkonium chloride (0, 1%, 0.3%), hydrogen peroxide (1.5%,3%), isopropyl alcohol 70%, potadine iodine(7.5%, 10%), and gentian violet (0.01 %, 0.1%, 1%). Bactericidal activity of disinfectants was assessed against MRSA (methicillin-resistant S. aureus), P. aeruginosa, VRE (vancomycin-resistant enterococci), K. pneumoniae. CNS (coagulase-negative staphylococci) and C albicens. Those microorganisms were obtained from the patients with hospital-acquired infections, In vitro susceptibility was determined using a macrodilution method with various exposure times to several concentrations of disinfectants of 30sec, 1 min, 2 min, 5 min, 15 min and 30 min. RESULT: Microorganism studied were killed after exposure to hibicol 0,5%, isopropyl alcohol 70%, pcradme iodine (7.5%, 10%) within 30sec. 0.05% chlorhexidine needs exposure time above 5 min for bactericidal action. 0.01% alkyl diaminoethyl glycine needs exposure time above 15 min. 0.1% and 0.3% benzalkonium chloride needs exposure time above 1 min. MRSA and P. aeruginosa were killed within 30sec after exposure to gentian violet (GV), but against CNS, 0.01% GV needs exposure time for 15min and 0.1% and 1% GV needs exposure time for 2 min. C. albicans were killed above 1 min. K. pneumoniae was not killed at all. H202 was ineffective for all tested bacteria. CONCLUSION: The results of this study show most disinfectants used in our hospital demonstrated bactericidal activity against major nosocomial pathogens. In-house diluted, 3% H202 failed to demonstrate killing of any microorganisms tested. The appropriate selection of disinfectants regarding to concentration and exposure time was necessary to inhibit growth of major nosocomial pathogens.

Bacterial resistance to antimicrobial agents: an overview from Korea

Antimicrobial resistance of bacteria has become a worldwide problem. Available data suggest that the resistance problem is comparatively more serious in Korea. In large hospitals, the proportion of methicillin-resistant Staphylococcus aureus (MRSA) has been reported at over 70%, and of penicillin-nonsusceptible Streptococcus pneumoniae at around 70%. Infection or colonization of vancomycin-resistant enterococci has started to increase. Extended-spectrum beta-lactamase producing Escherichia coli and Klebsiella pneumoniae has become widespread and even carbapenem-resistant Pseudomonas aeruginosa has been increasing. Community-acquired pathogens such as Salmonella, Shigella and Neisseria gonorrhoeae are often resistant to various antimicrobial agents. The prevalence of resistant bacteria can lead to erroneous empirical selection of either noneffective or expensive drugs, prolonging hospitalization and higher mortality. The emergence and spread of resistant bacteria are unavoidable unless antimicrobial agents are not used at all. The high prevalence of resistant bacteria in Korea seems to be related to antibiotic usage: 1) easy availability without prescription at drug stores, 2) injudicious use in hospitals, and 3) uncontrolled use in agriculture, animal husbandry, and fisheries. Nosocomial infection is an important factor in the spread of resistant bacteria. Antimicrobial resistance problems should be regarded as the major public health concern in Korea. It is urgently required to ban the sale of antibiotics without prescription, to use antibiotics more judiciously in hospitals by intensive teaching of the principles of the use of antibiotics, and to establish better control measures of nosocomial infections. Regulation of antimicrobials for other than human use should also be required. These issues are not easy to address and require the collective action of governments, the pharmaceutical industry, health care providers, and consumers.