Print E-mail
Volume 43, Number 6, December 2010

Time-related Increase of Staphylococci, Enterobacteriaceae and
Yeasts in the Oral Cavities of Comatose Patients

Fabrine Cecon, Luiz Eduardo Nunes Ferreira, Rosimeire Takaki Rosa, Lauren Christine Gursky, Alessandra de Paula e Carvalho, Lakshman Perera Samaranayake, Edvaldo Antonio Ribeiro Rosa

Received: June 9, 2007    Revised: February 6, 2009    Accepted: September 23, 2009   


Corresponding author:

Edvaldo Antonio Ribeiro Rosa, Pontifícia Universidade Católica do Paraná, Centro de Ciências Biológicas e da Saúde, Laboratório de Estomatologia, Rua Imaculada 1155–Prado Velho–80215-901–Curitiba, Brazil.1ConceiçãoE-mail:


Background and purpose: 

The composition of oral microbiota in comatose patients remains uncertain. Some pulmonary pathogens may be found in dental biofilms or as part of the saliva microbiota. It is supposed that some pneumopathogenic microorganisms may overgrow in the mouths of comatose patients and spread to their lungs.



The oral colonization dynamics of staphylococci, Enterobacteriaceae and yeasts in nine comatose patients (group 1), and in 12 conscious patients that brushed their teeth at least twice a day (group 2) was evaluated. Both groups were followed up for 7 days after hospitalization. Daily samples of saliva were obtained, dispersed and plated on selective culture media and colony forming units of each microbial group were obtained



For patients in group 1, the counts of total viable bacteria, staphylococci, Enterobacteriaceae and yeasts progressively increased in a time-dependant manner. For the conscious patients of group 2, there was no increase.



It would appear that concomitant consciousness and brushing teeth are determinants in controlling the selected pneumopathogen counts in resting saliva. The increase in microbial counts in comatose patients is understandable because these microorganisms could spread to the lungs.


Key words:

coma, Enterobacteriaceae, saliva, staphylococci, yeast