Journal of Clinical and Diagnostic Research, ISSN - 0973 - 709X

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On Sep 2018




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On Aug 2018




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Dr. Arundhathi. S
MBBS, MD (Pathology),
Sanjay Gandhi institute of trauma and orthopedics,
Bengaluru.
On Aug 2018




Dr. Mamta Gupta,
"It gives me great pleasure to be associated with JCDR, since last 2-3 years. Since then I have authored, co-authored and reviewed about 25 articles in JCDR. I thank JCDR for giving me an opportunity to improve my own skills as an author and a reviewer.
It 's a multispecialty journal, publishing high quality articles. It gives a platform to the authors to publish their research work which can be available for everyone across the globe to read. The best thing about JCDR is that the full articles of all medical specialties are available as pdf/html for reading free of cost or without institutional subscription, which is not there for other journals. For those who have problem in writing manuscript or do statistical work, JCDR comes for their rescue.
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Reviewing articles is no less a pain staking process and requires in depth perception, knowledge about the topic for review. It requires time and concentration, yet I enjoy doing it. The JCDR website especially for the reviewers is quite user friendly. My suggestions for improving the journal is, more strict review process, so that only high quality articles are published. I find a a good number of articles in Obst. Gynae, hence, a new journal for this specialty titled JCDR-OG can be started. May be a bimonthly or quarterly publication to begin with. Only selected articles should find a place in it.
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Dr. Mamta Gupta
Consultant
(Ex HOD Obs &Gynae, Hindu Rao Hospital and associated NDMC Medical College, Delhi)
Aug 2018




Dr. Rajendra Kumar Ghritlaharey

"I wish to thank Dr. Hemant Jain, Editor-in-Chief Journal of Clinical and Diagnostic Research (JCDR), for asking me to write up few words.
Writing is the representation of language in a textual medium i e; into the words and sentences on paper. Quality medical manuscript writing in particular, demands not only a high-quality research, but also requires accurate and concise communication of findings and conclusions, with adherence to particular journal guidelines. In medical field whether working in teaching, private, or in corporate institution, everyone wants to excel in his / her own field and get recognised by making manuscripts publication.


Authors are the souls of any journal, and deserve much respect. To publish a journal manuscripts are needed from authors. Authors have a great responsibility for producing facts of their work in terms of number and results truthfully and an individual honesty is expected from authors in this regards. Both ways its true "No authors-No manuscripts-No journals" and "No journals–No manuscripts–No authors". Reviewing a manuscript is also a very responsible and important task of any peer-reviewed journal and to be taken seriously. It needs knowledge on the subject, sincerity, honesty and determination. Although the process of reviewing a manuscript is a time consuming task butit is expected to give one's best remarks within the time frame of the journal.
Salient features of the JCDR: It is a biomedical, multidisciplinary (including all medical and dental specialities), e-journal, with wide scope and extensive author support. At the same time, a free text of manuscript is available in HTML and PDF format. There is fast growing authorship and readership with JCDR as this can be judged by the number of articles published in it i e; in Feb 2007 of its first issue, it contained 5 articles only, and now in its recent volume published in April 2011, it contained 67 manuscripts. This e-journal is fulfilling the commitments and objectives sincerely, (as stated by Editor-in-chief in his preface to first edition) i e; to encourage physicians through the internet, especially from the developing countries who witness a spectrum of disease and acquire a wealth of knowledge to publish their experiences to benefit the medical community in patients care. I also feel that many of us have work of substance, newer ideas, adequate clinical materials but poor in medical writing and hesitation to submit the work and need help. JCDR provides authors help in this regards.
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In the era of fast growing newer technologies, and in computer and internet friendly environment the manuscripts preparation, submission, review, revision, etc and all can be done and checked with a click from all corer of the world, at any time. Of course there is always a scope for improvement in every field and none is perfect. To progress, one needs to identify the areas of one's weakness and to strengthen them.
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Every one of us: authors, reviewers, editors, and publisher are responsible for enhancing the stature of the journal. I wish for a great success for JCDR."



Thanking you
With sincere regards
Dr. Rajendra Kumar Ghritlaharey, M.S., M. Ch., FAIS
Associate Professor,
Department of Paediatric Surgery, Gandhi Medical College & Associated
Kamla Nehru & Hamidia Hospitals Bhopal, Madhya Pradesh 462 001 (India)
E-mail: drrajendrak1@rediffmail.com
On May 11,2011




Dr. Shankar P.R.

"On looking back through my Gmail archives after being requested by the journal to write a short editorial about my experiences of publishing with the Journal of Clinical and Diagnostic Research (JCDR), I came across an e-mail from Dr. Hemant Jain, Editor, in March 2007, which introduced the new electronic journal. The main features of the journal which were outlined in the e-mail were extensive author support, cash rewards, the peer review process, and other salient features of the journal.
Over a span of over four years, we (I and my colleagues) have published around 25 articles in the journal. In this editorial, I plan to briefly discuss my experiences of publishing with JCDR and the strengths of the journal and to finally address the areas for improvement.
My experiences of publishing with JCDR: Overall, my experiences of publishing withJCDR have been positive. The best point about the journal is that it responds to queries from the author. This may seem to be simple and not too much to ask for, but unfortunately, many journals in the subcontinent and from many developing countries do not respond or they respond with a long delay to the queries from the authors 1. The reasons could be many, including lack of optimal secretarial and other support. Another problem with many journals is the slowness of the review process. Editorial processing and peer review can take anywhere between a year to two years with some journals. Also, some journals do not keep the contributors informed about the progress of the review process. Due to the long review process, the articles can lose their relevance and topicality. A major benefit with JCDR is the timeliness and promptness of its response. In Dr Jain's e-mail which was sent to me in 2007, before the introduction of the Pre-publishing system, he had stated that he had received my submission and that he would get back to me within seven days and he did!
Most of the manuscripts are published within 3 to 4 months of their submission if they are found to be suitable after the review process. JCDR is published bimonthly and the accepted articles were usually published in the next issue. Recently, due to the increased volume of the submissions, the review process has become slower and it ?? Section can take from 4 to 6 months for the articles to be reviewed. The journal has an extensive author support system and it has recently introduced a paid expedited review process. The journal also mentions the average time for processing the manuscript under different submission systems - regular submission and expedited review.
Strengths of the journal: The journal has an online first facility in which the accepted manuscripts may be published on the website before being included in a regular issue of the journal. This cuts down the time between their acceptance and the publication. The journal is indexed in many databases, though not in PubMed. The editorial board should now take steps to index the journal in PubMed. The journal has a system of notifying readers through e-mail when a new issue is released. Also, the articles are available in both the HTML and the PDF formats. I especially like the new and colorful page format of the journal. Also, the access statistics of the articles are available. The prepublication and the manuscript tracking system are also helpful for the authors.
Areas for improvement: In certain cases, I felt that the peer review process of the manuscripts was not up to international standards and that it should be strengthened. Also, the number of manuscripts in an issue is high and it may be difficult for readers to go through all of them. The journal can consider tightening of the peer review process and increasing the quality standards for the acceptance of the manuscripts. I faced occasional problems with the online manuscript submission (Pre-publishing) system, which have to be addressed.
Overall, the publishing process with JCDR has been smooth, quick and relatively hassle free and I can recommend other authors to consider the journal as an outlet for their work."



Dr. P. Ravi Shankar
KIST Medical College, P.O. Box 14142, Kathmandu, Nepal.
E-mail: ravi.dr.shankar@gmail.com
On April 2011
Anuradha

Dear team JCDR, I would like to thank you for the very professional and polite service provided by everyone at JCDR. While i have been in the field of writing and editing for sometime, this has been my first attempt in publishing a scientific paper.Thank you for hand-holding me through the process.


Dr. Anuradha
E-mail: anuradha2nittur@gmail.com
On Jan 2020

Important Notice

Original article / research
Year : 2012 | Month : May | Volume : 6 | Issue : 4 | Page : 632 - 635 Full Version

Significance of Coagulase Negative Staphylococcus Species in Blood Culture


Published: May 1, 2012 | DOI: https://doi.org/10.7860/JCDR/2012/.2151
Sapna Malik, K. Ravishekhar

1. Specialist Microbiology, ESIC Hospital Andheri (E). 2. Professor Microbiology, Pad. Dr. D. Y. Patil Medical College, Nerul, Navi Mumbai, India.

Correspondence Address :
Sapna Malik
C 1201, Jal Vayu Vihar, A.D.S. Marg,
Powai, Mumbai, India 400076.
E-mail: sapnawadhwan@hotmail.com

Abstract

A retrospective study was carried out from August 2009 to July 2010 to evaluate the rate of contamination in the blood cultures in a tertiary care hospital. A total number of 755 samples were tested for blood culture, 18% of these samples were labeled as contaminants; however, on further scrutiny, this was reduced to 16%. Determining whether a growth in the blood culture is a pathogen or a contaminant is a critical issue and multiple parameters have to be considered before arriving at a conclusion. Without a gold standard for truly distinguishing the contaminants from the true pathogens, it becomes inherently difficult to interpret the results and to institute preventive measures.

Keywords

CONS, Blood Culture pathogens, contaminants

INTRODUCTION
Septicaemia is a clinical syndrome which is characterized by fever, chills, malaise, tachycardia, hyperventilation and toxicity or prostration, which results when the circulating bacteria multiply at a rate that exceeds their removal by phagocytosis (1). During septicaemia, organisms are released into the blood stream at a fairly constant rate and also during the early stages of certain specific infections, bacteria continuously present in the blood stream. In patients with undrained abscesses, bacteria are found intermittently in the blood stream. In cases of the transient seeding of blood from a sequestered focus, bacteria are released into the blood approximately 45 minutes before a febrile episode (2). The mortality rate from septicaemia may be 40% or higher and hence, the timely recovery of bacteria from the patients’ blood can have a great diagnostic and prognostic importance. Hence, it becomes mandatory that every precaution must be taken to minimize the percentage of contaminated blood cultures. The critical factors which must be decided by the laboratory include the type of collection, the number and timing of the blood cultures, the volume of blood, the amount and the composition of the culture medium, when and how frequently to subculture and the interpretation of the results (1). The bacteraemia may be transient, continuous or intermittent and the blood cultures which are taken during this period may give false positive results. Coagulase Negative Staphylococcus (CONS) is frequently isolated from clinical samples including blood cultures, but their significance is difficult to interpret. CONS, which are often previously dismissed as culture contaminants, are assuming greater importance as true pathogens. The infections which are caused by these organisms involve indwelling foreign bodies and these are increasing as the number of catheters and artificial devices which are being inserted through the skin becomes higher. These infections are characterized by their indolence, but they may necessitate the removal of the catheter or the foreign device.

The resistance of the infecting isolates to multiple antibiotics may further complicate the therapy. The importance of CONS as nosocomial pathogens has prompted more interest in their detailed characterization. A working knowledge of the biology and the antimicrobial susceptibility of these organisms may be necessary to distinguish the infecting from the contaminating isolates and to devise the appropriate therapy. The various infections which are caused by CONS are urinary tract infections, osteomyelitis, native valve endocarditis, bacteraemia in immunosuppressed patients, endophthalmitis after ocular surgery and the infections which are caused by indwelling foreign devices (3). The blood culture contamination represents an ongoing source of frustration for the microbiologists and the clinicians alike (4). The ambiguous culture results often lead to a diagnostic uncertainty in the clinical management and these are associated with increased health care costs due to the unnecessary treatment and testing (4). The contaminated cultures have been recognized as a troublesome issue for decades. The increase in the use of central venous catheters (CVC) and other indwelling vascular devices have complicated the issue even more. The interpretation of the culture results for patients with CVC is challenging, because these individuals are at an increased risk for bacteraemia as well as for culture contamination or colonization of the line (4).

Material and Methods

Castenedas culture bottles from Himedia (dual performance medium) and the Hi Safe blood culturing system having a solid phase – 20 ml and a liquid phase – 40 ml for adults and 7 ml(solid phase) and liquid phase 20 ml for the paediatric age group were used for doing the blood culture testing. These bottles were incubated at 37ºC for 7 to 10 days and subcultures were performed after 24 hours of incubation (day 1), 72 hours of incubation (day 3), 120 hours of incubation (day 5) and 240 hours of incubation (day 10) on chocolate agar, blood agar and Mac Conkey’s agar. These plates were incubated for 18 to 24 hours at 37ºC and the growth, if any, was identified by the standard CLSI procedures (1).

Two samples of blood cultures were obtained from all the groups, except neonates, from which only one sample was obtained.

Results

A retrospective study was done from August 2009 to July 2010, in which a total number of 755 samples were received. This included 263 adult, 352 paediatric and 140 neonatal samples. 136 of the total number of 755 blood cultures which were done, grew organisms such as Micrococcus, coagulase negative Staphylococcus spp. (CONS) and diphtheroids. Among the 263 adult samples, 28 grew Micrococcus spp., 11 samples grew CONS and 3 grew diphtheroids. In the paediatric age group of 352 samples, 54 grew Micrococcus spp. 17 grew CONS and 6 samples grew diphtheroids. Among the 140 neonatal samples, 8 samples grew micrococcus and 9 grew CONS. No diphtheroids were isolated from this group of patients.

(Table/Fig 1) – Total number of samples received according to age distribution & number of positive isolates.

(Table/Fig 2) – Various organisms isolated from various age groups.

(Table/Fig 3) – Number of positive blood cultures according to days ofsub-culture.

(Table/Fig 4)-Contaminant organisms according to day wise break up.

Discussion

As per our study, the contamination rate of the blood culture was 18 %, while the target rates for the contamination should ideally not exceed 2%-3% [5,6]. The actual rates for the contamination vary widely from institution to institution, ranging from 0.6% to over 6% (4). Certain organisms which are found to represent the contamination included, coagulase negative Staphylococcus spp. (CONS), Corynebacterium spp., Bacillus spp. other than Bacillus anthracis, Propionibacterium acnes, Micrococcus spp., viridans group Streptococci, Enterococci and Clostridium perfringens [7,8]. However, each of these organisms could represent true bacteraemia with devastating consequences, particularly if they were left untreated due to their misinterpretation as contaminants and hence the determinants of the contamination in the blood cultures is very essential. Studies which were done in Virginia (USA) and south India also showed that these organisms, particularly CONS, were an increasing source of true bacteraemia, especially in patients with prosthetic devices and central venous catheters [4,9]. Therefore, it is extremely important that certain criteriae are set for determining the contamination in the blood cultures like 1. Source of the culture – Percutaneous vs Catheter drawn When the blood cultures which are drawn from catheters are positive, it could indicate three possibilities. a. True Bacteraemia b. Catheter Colonization c. Culture Contamination The catheter colonization may or may not progress to cause symptoms of infection or true bacteraemia. 15%–25% of the short term central venous catheters are colonized by CONS and most of them have no evidence of infection and hence a substantial number of patients who have CVC are expected to be positive due to colonization (10). Sterilizing the catheters prior to the blood collection is more difficult than sterilizing the skin. 2. Time to positivity (Time to growth) – Cultures that are positive for more than 3–5 days after incubation are more likely to represent contamination, as the continuous monitoring of the blood cultures to detect the growth advances the time to growth and the sensitivity for detecting the growth can be expected to change. However, some experts say that this should not be relied upon to distinguish the contaminants from the pathogens in the blood cultures (11). 3. Quantity of growth per culture bottle – Similar to the quantitation of urine, the quantitation of sputum and catheter related blood stream infections can be done for routine blood cultures. However, a low colony count should not be dismissed as a contamination in a high risk population [11,12]. 4. Number of blood culture sets – Usually one set of blood cultures involves one aerobic and one unaerobic bottle. A minimum of two blood culture sets per episode should be drawn. However, these two sets are not obtained always. The results of multiple positive cultures may be helpful, but they are still imperfect with respect to the discernment the contamination. 5. Clinical condition of the patient – The clinical criteria to detect true bacteraemia from the contamination should also be used. In our study, we found that 6 out of 17 CONS isolates in the paediatric age group were MRCONS and that they all grewon the 2nd day, except one that grew on 3rd day. Similarly, in adults, 4 MRCONS grew on 2nd day and one grew on 3rd day. In the neonatal isolates, 2 MRCONS grew on 2nd day. However, MSCONS across all the age groups also grew on 2nd day or 3rd day of the culture. Thus, it becomes difficult for the laboratory to issue a report of bacteraemia. In these cases, we correlated the antibiotic sensitivity pattern of the isolates and the clinical condition of the patients, as surveillance by antibiotyping with attention to the multiresistant profile and the warning to clinicians is necessary [9,13,14,15]. Studies which were done in Jamaica, West Indies, also stressed the need for a careful evaluation of CONS which were isolated from the blood cultures before instituting the therapy, to avoid the unnecessary use of antibiotics, especially vancomycin, and The consequent increase of antibiotic resistance in hospitals (15). Based on the above mentioned criteria, 13 more isolates were reclassified as pathogens, thereby bringing down the rate of contamination from 18% to 16%. The specificity of the blood cultures is directly related to the rate of the false positive results which are increasingly caused by the contamination. Reduction of the contamination rates leads to an improved specificity and a better performance of this test.

The factors which are responsible for the contamination would be: 1. Skin preparation – Skin antisepsis cannot entirely prevent the contamination of the blood culture because as many as 20 % of the skin associated bacteria have been found to survive disinfection. These bacteria can be located in the deep layers of the skin or in other structures where antiseptics cannot penetrate. Investigators have found that the median contamination rate was significantly lower in settings where tincture iodine was used (2.1%) as against an iodophore (2.6% p = 0.036). A study found that 0.5 % Chlorhexidine and alcohol had significantly lowered the contamination rates than the standard povidone iodine group (p=0.065) The time which is required for the antiseptic to have a maximum effect is an important consideration eg. The Povidone iodine preparation requires 1.5–2.00 mins of contact time to have a maximal antiseptic effect, whereas tincture iodine requires only 30 seconds. This difference in the time may possibly account for the differences in contamination which were seen in many of the studies. Experts have recommended, although it is controversial, that the culture site should be prepared with 70 % isopropyl/ethyl alcohol, allowed to air dry and that a second preparation of 1-2 % iodine or 10 % povidone – iodine should also be applied (16). 2. Single needle vs double needle – This effect has been evaluated by several control studies. All the authors admitted to be having inadequate power to detect the level of difference that was actually observed between the two techniques. A CAP survey of 640 institutions in 1997 concluded that the difference in contamination was not statistically significant (17). 3. Phlebotomy team – Dedicated and trained phlebotomy teams have been found to decrease the culture contamination rates [7,18,19]. 4. Preparation of the blood culture bottle – The rubber stopper on each blood culture bottle is not sterile, despite being covered by the lid, that requires its removal prior to the inoculation. It has been found that institution that prepped (preparation of blood culture bottle) the bottle tops had significantly lower contamination rates 2.3 % than those that did not prepped the bottle tops 3.4% (4).

Conclusion

In our study, we found that out of a total of 755 blood cultures, 123 were contaminants, thus bringing the contamination rate to 16 %. However, we did not have any definite criteria to identify the true bacteraemias. Despite the progress that has been made in distinguishing the contamination from the true bacteraemia, significant barriers remain. Without a gold standard for truly distinguishing the contaminant organisms from the true pathogens, studies that seek to measure the success of the prevention strategies are inherently limited. Additional research on the value of time to the positivity and the quantity of growth for differentiating the culture contamination from the bacteraemia is necessary. Information technology may have a role in facilitating the detection of the contamination, in assisting in the clinical decision making and enabling better systems for tracking the c ontamination rates both within and between institutions. In the paediatric age group, additional studies are needed for interpreting the results of single blood cultures that grow CONS. Blood culture contamination is a complex challenging problem that requires a multidisciplinary approach. More research is needed to refine these models and to test them.

References

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Washington Winn, Jr, Stephen Allen, William Janda, Elmer Koneman, et al. Koneman’s Color Atlas and Textbook of Diagnostic Microbiology, 5th Edition.
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Forbes BA, Sahm DF, Weissfeld AS. Bailey and Scott’s Diagnostic Microbiology, 12th Edition, Page 779.
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Mandell GL, Bennett JE, Dolin R. Mandell, Douglas, and Bennett’s Principles and the Practice of Infectious Diseases, 5th Edition, Volume 2, Page 2092.
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Hall KK, Lyman JA. Updated review of blood culture. Clinical Microbiology Review 2006Oct;19 (4): 788-802.
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Chandrasekar PH, Brown WJ. Clinical issues of blood cultures. Arch. Internal Medicine 1994; 154 : 841-49.
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Chapnick EK, Schaffer BC, Gradon JD, Lutwick LL, Krigsman SA, Lev M, Techniques for drawing blood cultures : is changing needles trulynecessary ? Southern Med Journal 1991; 84: 1197-98.
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Weinbaum FL , Lavie S, Danek M, Sixsmith D, Heinrich GF, Mills SS. Doing it right the first time: quality improvement and the contaminant blood culture. J. Clinical Microbiology 1997; 35:563-65.
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Weinstein MP, Towns ML, Quartery SM, Mirrett S, Reimer LG, ParigianiG, Reller LB. The clinical significance of positive blood cultures in the1990s: a prospective comprehensive evaluation of the microbiology, epidimeology and the outcome of bacteremia and fungemia in adults. Clin. Infect. Dis 1997; 24 : 584-602.
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Dias E, Vigneshwaran P. The bacterial profile of neonatal septicaemia in a rural hospital in south India. Journal of Clinical and Diagnostic Research 2010 Dec; 4(6): 3328-31.
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Committee for the Development of Guidelines for the prevention of Vascular Catheter Associated Infections, Indian Society of Critical Care Medicine, Indian Journal of Critical Care Medicine 2003;7-5.
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Kasis C, Rangaraj G, Jiang Y, Hachem RY, Raad I. Differentiating culture samples which represent coagulase negative Staphylococcal bacteremia from those which represent contamination by the use of time to positivity and quantitative blood culture methods. Journal of Clinical Microbiology 2009 Oct;47(10): 3255-60.
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