Indian Journal of Dental Research

ORIGINAL RESEARCH
Year
: 2012  |  Volume : 23  |  Issue : 6  |  Page : 841-

Microbiology of the white coat in a dental operatory


M Malini1, Titus K Thomas1, Darpan Bhargava2, Smiline Girija3,  
1 Department of Oral and Maxillofacial Surgery, Meenakshi Ammal Dental College and Hospital, Alapakkam Main Road, Maduravoyal, Chennai, Tamil Nadu, India
2 Department of Oral and Maxillofacial Surgery, Peoples College of Dental Sciences and Research Center, Peoples University, Bhanpur, Bhopal (M.P), India
3 Department of Microbiology, Meenakshi Ammal Dental College and Hospital, Alapakkam Main Road, Maduravoyal, Chennai, Tamil Nadu, India

Correspondence Address:
Darpan Bhargava
Department of Oral and Maxillofacial Surgery, Peoples College of Dental Sciences and Research Center, Peoples University, Bhanpur, Bhopal (M.P)
India

Abstract

Background: It remains important to have a thorough knowledge of the micro-flora harboring the white coats of doctors to minimize cross-contamination and improve patient safety by reducing the risk of nosocomial infections. This study presents the microbiological analysis of the white coats in clinical departments of a dental college and hospital. Materials and Methods: The swabs for the study were taken from the white coats of undergraduate students posted in various clinical departments, interns, and the post-graduate students. The microbial contamination was studied by observing and recording the colony morphology on the culture plates, Gram«SQ»s staining with light microscopic screening of the slides, and the biochemical characterization of the isolates using standard microbiology protocols. Results: Microbiological analysis of swabs taken from the white coats in the dental operatory showed that 100% coats had bacterial contamination. Out of 30 swabs collected, 46 cultures were obtained. 50% cultures showed Gram-positive cocci, making it the major microbial group contaminating the white coats in the dental operatory. Conclusion: The presented study highlights the fact that the white coats are a potential source of cross infection. The results of this study mandate a strict audit process and protocols to be set in place for preventing cross-contamination from the white coats in a dental operatory.



How to cite this article:
Malini M, Thomas TK, Bhargava D, Girija S. Microbiology of the white coat in a dental operatory.Indian J Dent Res 2012;23:841-841


How to cite this URL:
Malini M, Thomas TK, Bhargava D, Girija S. Microbiology of the white coat in a dental operatory. Indian J Dent Res [serial online] 2012 [cited 2020 Oct 24 ];23:841-841
Available from: https://www.ijdr.in/text.asp?2012/23/6/841/111289


Full Text

There have been reports that the white coats, nurses' uniforms, and other hospital garments may play an important role in transmitting pathogenic bacteria in a hospital setting. [1] Grys and Pawlaczyk in their interesting article in Polish commented that "although traditionally a big attention is put on wearing white coats by ward staff, in many instances it's protective effect is overestimated, while other factors may be of importance." [2] It is well accepted that proper handling of white coats by physicians and other healthcare workers could minimize cross-contamination and improve patient safety by potentially reducing nosocomial infections; it remains important to have a thorough knowledge of the micro-flora harboring these white coats. [3] Dental operatory has always been a high-priority zone regarding the risk of infections. [4] This study presents the microbiological analysis of the white coats in clinical departments of a dental college and hospital.

 Materials and Methods



The study was conducted by the Department of Oral and Maxillofacial Surgery with technical aid from the Department of Microbiology at Meenakshi Ammal Dental College and Hospital and Clinical Microbiology laboratory at Meenakshi General Hospital, Chennai, India. The study aimed at assessing the profile of microbial contamination of white coats used by the dentists in various clinical departments. For the study, microorganisms needed to be efficiently collected from the sampling site, carried by an inert vector, and then must be recovered from this for subsequent analysis. Medical grade sterile cotton swabs with a plastic casing and brain heart infusion (BHI) media were found suitable to serve the purpose, and were in accordance with "Quality Control of Microbiological Transport Systems; Approved Standard" by Clinical Laboratory Standards Institute (2003). [5] The swabs for the study were taken from the white coats of undergraduate students posted in various clinical departments, interns, and the post-graduate students. Swabs were taken from the doctors' coat of two undergraduate students, two interns, and two post-graduate students from five clinical departments in the dental hospital, with a total of 30 samples collected for the study. For obtaining the samples from the coats, a sterile cotton swab was used, which was transported in the BHI media to the microbiology laboratory after taking the samples. Swabs placed in BHI media were incubated for 2 h at 37°C and then the sub-cultures were transferred to the Mac Conkey and blood agar plates, which were then incubated at 37°C for 24 h. After 24 h of incubation, the colony morphology was observed on the culture plates [Figure 1]. Gram's staining with light microscopic screening of the slides [Figure 2] and the biochemical characterization [Figure 3] of the isolates were performed using standard microbiology protocols [Table 1], [Table 2], [Table 3] and [Table 4]. Biochemical evaluation used for the study included testing for catalase, coagulase, bile, oxidase, triple sugar iron, indole, and citrate using standard prescribed protocols for identification and characterization of microorganisms of medical importance. [6]{Figure 1}{Figure 2}{Figure 3}{Table 1}{Table 2}{Table 3}{Table 4}

 Results



Microbiological analysis of swabs taken from the white coats in the dental operatory showed that 100% coats had bacterial contamination. Out of 30 swabs collected, 46 cultures were obtained [Table 1]. Gram-positive cocci dominated the colonization on white coats, followed by Gram-negative cocci [Table 2], [Table 3] and [Table 4]. 50% cultures showed Gram-positive cocci, making it the major microbial group contaminating the white coats in the dental operatory [Figure 4]. Among the Gram-positive cocci, coagulase-negative staphylococcus was the dominant microbe. Gram-negative coccus (24%), Gram-positive bacilli (15%), and Gram-negative bacilli (11%) constituted the remaining 50% of the white coat microbial contamination. The organisms isolated from the white coats are summarized in [Table 3] and [Table 4]. This is a uni-centric pilot study, done to create awareness among our dental colleagues. This study reflects center-specific microbial contamination in a dental operatory. To reach a more generalized conclusion, the study requires a multicentric evaluation with a larger sample size.{Figure 4}

 Discussion



This study evaluated the type of microbial contamination present on the white coats of the clinicians working in a dental operatory. Gram-positive cocci were isolated in high numbers in this study (50% of the total cultures obtained); this remains consistent with other studies performed. [5],[7] The intervals at which the coats were washed were not included as a study parameter as it has been emphasized in literature that the coats become contaminated quickly once worn and there appears to be little difference between the colony counts according to the frequency of laundering. [7] Wong et al. in their research paper on the microbial flora on doctors' white coats have concluded that the white coats that were judged to be dirty (by appearance) did not differ in the level or type of microbial contamination from the clean white coats, which suggests that appearance does not necessarily indicate the degree of microbial colonization. [1] They also commented in their study that the microbial counts do not vary with "time in use" of the white coat and a steady state of maximal microbial contamination is attained within the first week of use and does not change significantly thereafter. [1]

Most of the organisms isolated in this study from the doctor's coats were potentially pathogenic. Among the Gram-positive cocci isolated in the study, the coagulase-negative staphylococci are clinically significant organisms implicated for nosocomial infection. These organisms are common colonizers of skin and possess a risk of cross-contamination to patients with prosthetic devices, intravascular catheters, and immunocompromised hosts. Streptococcus viridans is the organism that causes endocarditis in individuals with damaged heart valves. Micrococci are a common cause of bloodstream infections and can become an opportunistic pathogen in patients with compromised immune system. Pneumococci are potential pathogenic organisms that can cause pneumonia, endocarditis, cellulites, and sinusitis. Enterococcus faecalis is another organism implicated for endocarditis. It is also a predominant pathogen in endodontic infections, peri-radicular abscess, marginal periodontitis, and persistent drug-resistant infections. The Gram-negative cocci - Neisseria catarrhalis - though are non-pathogenic normally, may cause upper and lower respiratory tract infections in cases of altered immune response. Among the Gram-negative bacilli isolated in the study, Escherichia coli is potentially pathogenic and may cause opportunistic infection of the urinary tract and septicemia in extreme cases. Klebsiella pnuemoniae is one of the most common causes of nosocomial infection affecting lower respiratory tract, surgical wound sites, and urinary tract. Pseudomonas aeruginosa is an opportunistic pathogen that infects the pulmonary tract, burn wounds, and is also implicated for surgical site infections. [6]

The white coat is a symbol of the medical profession; many a times, a doctor is identified in a medical setup with his white coat. The presented study highlights the fact that these white coats are a potential source of cross infection. As emphasized in a number of studies, the potential solution to this problem may be wearing of impermeable clothing, such as plastic aprons and gloves. [8],[9] The material from which white coats are made may also be altered to a plastic-laminated clothing or a closely woven waterproof cotton, which can reduce the bacterial transfer rate and cross-contamination. [9] The results of this study mandate a strict audit process and protocols to be set in place for preventing cross-contamination from the white coats in a dental operatory.

References

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