Study on the In Vitro Activity of Five Disinfectants against Nosocomial Bacteria

Nosocomial infections cause significant morbidity and mortality worldwide, and the pathogenic organisms responsible for such infections can develop resistance to antimicrobial agents. Understanding the activity of disinfectants against clinical and environmental bacterial isolates is therefore crucial. We analysed the in vitro activity of five antimicrobial products (phenolic compounds, didecyldimethylammonium chloride (DDAC), sodium hypochlorite, isopropanol + ammonium compounds (IACs), hydrogen peroxide) against 187 bacterial strains comprising clinical isolates, as well as 30 environmental isolates of Pseudomonas aeruginosa from hospital water samples. Disk diffusion assays were employed to assess antimicrobial activity. Hydrogen peroxide was significantly more active (p < 0.0001) than the other disinfectants against all P. aeruginosa, Klebsiella pneumoniae, Enterococcus faecalis and Staphylococcus aureus strains. It was also the only disinfectant with activity against both clinical and environmental strains of P. aeruginosa. DDAC and IAC-based disinfectants were ineffective against Gram-negative strains, but showed significant activity (particularly IACs, p < 0.0001) against the Gram-positive strains. Compared with IACs, DDAC was significantly more active on E. faecalis and less active on S. aureus (p < 0.0001). Sodium hypochlorite and phenol compounds, by contrast, were inactive against all bacterial strains. The development of disinfection procedures that are effective against all microorganisms is essential for limiting the spread of nosocomial infections.

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IN VITRO ACTIVITY OF ANTIMICROBIAL AGENTS AGAINST OXACILLIN RESISTANT STAPHYLOCOCCI WITH SPECIAL REFERENCE TO STAPHYLOCOCCUS HAEMOLYTICUS

Indian Journal of Medical Microbiology ◽

10.1016/s0255-0857(21)02234-9 ◽

2007 ◽

Vol 25 (1) ◽

pp. 50-52

Author(s):

A Chaudhury ◽

AG Kumar

Keyword(s):

Special Reference ◽

Antimicrobial Agents ◽

Vitro Activity ◽

In Vitro Activity ◽

Staphylococcus Haemolyticus

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1375. In vitro Activity of Cefiderocol and Comparator Agents against Gram-Negative Isolates from Cancer Patients

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy210.1206 ◽

2018 ◽

Vol 5 (suppl_1) ◽

pp. S421-S422 ◽

Cited By ~ 2

Author(s):

Kenneth V I Rolston ◽

Bahgat Gerges ◽

Issam Raad ◽

Samuel L Aitken ◽

Ruth Reitzel ◽

...

Keyword(s):

Cancer Patients ◽

Active Agent ◽

Vitro Activity ◽

Significant Activity ◽

In Vitro Activity ◽

Research Support ◽

Gram Negative ◽

E Coli ◽

Research Grant

Abstract Background Gram-negative bacilli (GNB) are now the predominant cause of bacterial infection in cancer patients (CP). Many GNB are problematic because they have become resistant to commonly used antibiotics. Cefiderocol (CFDC), a novel siderophore cephalosporin, is active against a wide spectrum of GNB. We evaluated its in vitro activity and that of eleven comparator agents against GNB isolated from CP. Methods A total of 341 recent GNB blood isolates from CP were tested using CLSI approved methods for MIC determination by broth microdilution. Comparator agents were amikacin (A), aztreonam (AZ), ceftazidime (CZ), ceftazidime/avibactam (CAV), cefepime (CEF), ciprofloxacin (CIP), colistin (CL), meropenem (MR), ceftolozane/tazobactam (C/T), tigecycline (TG), and trimethoprim/sulfamethoxazole (T/S). Results CFDC MIC90s as mg/L were: S. maltophilia [50 isolates] 0.25, E. coli (ESBL−) [50 isolates] 0.5, E. coli (ESBL+) [51 isolates] 2.0, K. pneumoniae (ESBL− and +) [60 isolates] 0.5; K. pneumoniae (CRE) [22 isolates] 2.0; P. aeruginosa (MDR) [32 isolates] 1.0; E. cloacae [27 isolates] 4.0; Achromobacter spp. [15 isolates] 0.12. CFDC inhibited P. agglomerans, Burkholderia spp., Sphingomonas spp., Ochrobactrum spp. at ≤1 mg/L [23 total isolates] and Elizabethkingia spp. and R. radiobacter at ≤8 mg/L [11 total isolates]. Among comparator agents, only T/S had consistent activity against S. maltophilia. For E. coli (ESBL− and +) MR, TG, CAV, CL were most active. For K. pneumoniae (ESBL–and +) MR, CAV were most active. For K. pneumoniae (CRE) and P. aeruginosa (MDR), none of the comparators had significant activity. For E. cloacae, MR, A, CAV, TG were most active. Among the uncommon organisms, MR and TG had the greatest activity. Conclusion Although susceptibility breakpoints have yet to be determined, CFDC has significant activity (≤4 mg/L) against most problematic Gram-negative organisms causing infections in CP based on available pharmacokinetic/pharmacodynamic data. In particular, its activity against S. maltophilia was superior to the comparators. Also, it was the most active agent against P. aeruginosa (MDR) and K. pneumoniae (CRE). Based on our results, CFDC warrants clinical evaluation for the treatment of blood stream infections caused by GNB in CP. Disclosures K. V. I. Rolston, Merck: Investigator, Research grant; JMI Laboratories: Investigator, Research grant; Shionogi (Japan): Investigator, Research grant. B. Gerges, Shionogi: Collaborator, Research support. S. L. Aitken, Shionogi: Scientific Advisor, Consulting fee; Merck: Scientific Advisor, Consulting fee; Medicines Co: Scientific Advisor, Consulting fee; Achaogen: Scientific Advisor, Consulting fee; Zavante: Scientific Advisor, Consulting fee; R. Prince, Shionogi: Investigator, Research support. Merck: Investigator, Research support.

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