|Year : 2012 | Volume
| Issue : 4 | Page : 482-483
Department of Microbiology SV Institute of Medical Sciences, Tirupati, Andhra Pradesh 517507, India
|Date of Submission||16-Jul-2012|
|Date of Acceptance||23-Jul-2012|
|Date of Web Publication||24-Nov-2012|
Department of Microbiology SV Institute of Medical Sciences, Tirupati, Andhra Pradesh 517507
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Chaudhury A. Author's reply. Indian J Med Microbiol 2012;30:482-3
We thank our colleague for critically going through the article "Isolation, speciation and antibiogram of clinically relevant non-diphtheroidal corynebacteria (Diphtheroids)"  and for the remarks. A few points have been raised to which I like to respond as follows:
- The total number of samples processed during the study period of 18 months with the corresponding break-up of isolates could not be included because that would have necessitated the inclusion of various other isolates obtained from all the samples which would have added unnecessary bulk to the article with a deviation from the primary objective.
- The study was conducted in a tertiary care hospital with a large population of patients with some compromise of the immune system due to multiple reasons. This may explain the isolation of 114 clinically relevant isolates of this particular group of organism from this centre over a period of one and a half years. Whether to call this number very high is a relative matter which depends on the volume of samples handled by the particular laboratory.
- It has been mentioned that no other centre from India has reported similar findings. In fact, as we have also mentioned in the introduction, there was not a single report from India at the time of preparation of the manuscript where this issue has been addressed to. The significance of diphtheroids in clinical specimen at most of the centres in India is overlooked and not given due importance. However, similar data are available from quite a few reports from other countries including the report by Camello et al. from Brazil.
- The isolation of diphtheroid from CSF is indeed a rare event and in our series, we came across one isolate belonging to CDC Group G from a patient with classical signs and symptoms of acute meningitis and the Gram stain had revealed inflammatory cells and few short Gram-positive rods.
- As we have mentioned in the materials and methods, only those pus samples which showed pure growth of diphtheroids were included in the study. For this, we have followed the dictum mentioned in the discussion that "coryneform organisms are to be considered as clinically significant organisms whenever they are isolated in pure culture, or isolated from a sterile site, or isolated repeatedly". . As it has been rightly pointed out, we do come across diphtheroids occurring as prominent growth along with other established and more virulent organisms like Staphylococcus aureus. In all such cases, the diphtheroids need not be processed further and we have followed the same principle.
- The significance of diphtheroids in catheter tips in the absence of clinical features and blood stream infection has been mentioned in the discussion. These are part of the biofilm developing in the catheters. Regarding the management of such biofilm infection of the catheters, which may lead to future blood stream infection due to dislodgement of the vegetation, various modalities have been suggested. One such modality is catheter lock technique.  The guidelines from the Infectious Diseases Society of America and CDC, Atlanta, mention the use of antibiotic lock as prophylaxis for catheter-related infections in selected patient populations only, but includes its use as a therapeutic option for intra-luminal infection when the device is not removed. 
| ~ References|| |
|1.||Reddy BS, Chaudhury A, Kalawat A, Jayaprada R, Reddy GSK, Ramana BV. Isolation, speciation and antibiogram of clinically relevant non-diphtheroidal corynebacteria (Diphtheroids). Indian J Med Microbiol 2012;30:52-7. |
|2.||Funke G, Bernard KA. Coryneform Gram-positive rods. In: Murray PR, Baron EJ, editors. Manual of clinical Microbiology. Vol. 34, 8th ed. Washington: ASM Press; 2003. p. 472-96. |
|3.||Chaudhury A, Jayaprada R, Venkatramana B. Catheter lock technique: in vitro efficacy of ethanol for eradication of methicillin-resistant staphylococcal biofilm compared with other agents. FEMS Immunol Med Microbiol 2012; 65: 305- 308. |
|4.||O'Grady NP, Alexander M, Burns LA et al. Guidelines for the prevention of intravascular catheter-related infections. Am J Infect Control 2011; 39(Suppl1): S1-S34. |