Back to Journals » Infection and Drug Resistance » Volume 12

More caution needs in study design and method selection for “In vitro antibacterial effect of Deconex and sodium hypochlorite against bacterial taxa isolated from dental units” [Letter]

Authors Emami A, Pirbonyeh N, Javanmardi F

Received 28 April 2019

Accepted for publication 7 August 2019

Published 28 August 2019 Volume 2019:12 Pages 2655—2656

DOI https://doi.org/10.2147/IDR.S213787

Checked for plagiarism Yes

Editor who approved publication: Dr Sahil Khanna

Download Article [PDF] 

Amir Emami, Neda Pirbonyeh, Fatemeh Javanmardi

Department of Microbiology, Burn and Wound Healing Research Center, Shiraz University of Medical Sciences, Shiraz, Fars, Iran

Correspondence: Amir Emami
Department of Microbiology, Burn and Wound Healing Research Center, Amir-Al-Momenin Burn and Wound Healing Hospital, Shiraz University of Medical Sciences, Shiraz, Fars, PO Box 719875436, 
Iran
Email [email protected]

Recently, we have meticulously read the paper by Amin et al1 about the effect of Deconex and sodium hypochlorite on bacterial taxa isolated from dental faculty units in Ahvaz Jundishapure University of Medical Sciences. Firstly, we are fortunate that a specialist evaluates axiomatic fact. According to the confirmed antimicrobial effect of deconex product by Borer Chemie AG based on its certificates (VAH: German Association for Applied Hygiene, CE1250 by Switzerland and EC-certificate by registration number 33818),2 no more tests are needed for confirmation, especially by non-specialized sections. These tests are merely administered by oversight organizations such as Food and Drug Administration (FDA) or infection control committee of Ministry of Health and Medical Education from approved and specialized laboratories. Currently, according to the categories of international FDA, alcoholic-based compounds are approved to be used as safe disinfectants especially in moderate conditions (not high-dose infections). Accordingly, it would be baseless to verify such compounds. Based on obvious data and the mechanism of alcoholic compounds on microbial proteins, no valid reports have been recently submitted about the formation of resistance against alcoholic-based disinfectants, not even in prolonged applications.3

View the original paper by Amin and colleagues

A Response to Letter has been published for this article

Dear editor

Recently, we have meticulously read the paper by Amin et al1 about the effect of Deconex and sodium hypochlorite on bacterial taxa isolated from dental faculty units in Ahvaz Jundishapure University of Medical Sciences. Firstly, we are fortunate that a specialist evaluates axiomatic fact. According to the confirmed antimicrobial effect of deconex product by Borer Chemie AG based on its certificates (VAH: German Association for Applied Hygiene, CE1250 by Switzerland and EC-certificate by registration number 33818),2 no more tests are needed for confirmation, especially by non-specialized sections. These tests are merely administered by oversight organizations such as Food and Drug Administration (FDA) or infection control committee of Ministry of Health and Medical Education from approved and specialized laboratories. Currently, according to the categories of international FDA, alcoholic-based compounds are approved to be used as safe disinfectants especially in moderate conditions (not high-dose infections). Accordingly, it would be baseless to verify such compounds. Based on obvious data and the mechanism of alcoholic compounds on microbial proteins, no valid reports have been recently submitted about the formation of resistance against alcoholic-based disinfectants, not even in prolonged applications.3

In case of any report on inappropriate decontamination findings, the cause might have been an incorrect application of reagents according to the international and company recommendations (it is mentioned briefly in the introduction part).

In addition, there are some confusing explanations in the method section which are against standard techniques and Clinical Laboratory Standard Institute (CLSI) guideline. The authors claim that as many as 100 samples were taken from different parts of 10 different units from different divisions. Due to the dispersion of the sampling, how did the authors conclude the greatest contamination persists in all 10 units of 3 studied (!!!) divisions (oral medicine, root canal therapy and surgery) with the rest of 9 other units from other divisions?

In the first step for isolates detection, hot dyeing (or Ziehl-Neelsen) method is introduced, but this method is used in phenotypic tests only for mycobacteria, not for the detection of routine growth bacteria, which must be detected by gram stain technique.4,5 Then, this method of staining is not applicable for screening of the studied isolates.

Based on many standards and reports, disinfection agents must be evaluated by Phénol coefficient technique, not by minimal inhibitory concentration (MIC) technique which has been wrongly applied.6 In the Phénol coefficient technique, we can examine the effect of the time and strength of the studied compound without changing its nature, especially the standard concentration of the studied compounds. In addition, according to the CLSI standard method for MIC, the inoculation of bacteria to the microtiter plate wells is limited in volume and in number. Maximum volume and number of bacteria test in microdilution technique is 5 µL with the highest concentration of 5×104–5 CFU/mL, while the authors declared that total of 50 µL of the bacterial sample have been inoculated with concentration of 1×106 to the test wells, which is twice more than the permitted standard.7 Given that the Journal of Infection and Drug Resistance is a valuable source of methods and data related to this filed, it is requested that articles and methods submitted for publication be more precisely reviewed.

Disclosure

The authors report no conflicts of interest in this communication.

References

1. Amin M, Ardaneh M, Hashemzadeh M, Dezfuli AA, JafarZadeh E. In vitro antibacterial effect of deconex and sodium hypochlorite against bacterial taxa isolated from dental units. Infect Drug Resist. 2019;12:805.

2. SQS C. EC- Certificate. Swiss Association for Quality and Managment System SQS. 2013. Available from: www.borer.ch/fileadmin/_migrated/content_uploads/RL_93-42-EWG_1_CE_1250_EN.pdf. Accessed August 08, 2019.

3. Cariz J. Hospital superbug becoming resistant to alcohol disinfectants. Am Assoc the Adv Sci. 2018;1(1):1–5.

4. Harada K. The nature of mycobacterial acid-fastness. Stain Technol. 1976;51(5):255–260.

5. Coico R. Gram staining. Curr Protoc Microbiol. 2005; Appendix 3 (Appendix 3c):1–5.

6. Jensen V, Jensen E. Determination of the phenol coefficient of disinfectants by the cover-slip method. J Hyg (Lond). 1933;33(4):485–494.

7. CLSI. Performance standards for antimicrobial susceptibility testing. Clin Lab Stand Inst. 2016;1(26):62–65.

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]