[Isolation of alpha-streptococci with inhibitory activity against pathogens, in the oral cavity and the effect of tobacco and gargling on oral flora]

Microbiology of Acute and Chronic Maxillary Sinusitis in Smokers and Nonsmokers

Objectives:

We evaluated the microbiology of sinus aspirates of smokers and nonsmokers with acute and chronic maxillary sinusitis.

Methods:

Cultures were obtained from 458 patients, 244 (87 smokers and 157 nonsmokers) of whom had acute maxillary sinusitis and 214 (84 smokers and 130 nonsmokers) of whom had chronic maxillary sinusitis, between 2001 and 2007.

Results:

A greater number of Staphylococcus aureus, methicillin-resistant S aureus (MRSA), and beta-lactamase–producing bacteria (BLPB) were found in the 87 smokers with acute sinusitis than in the nonsmokers with acute sinusitis (p < 0.005, p < 0.025, and p < 0.05, respectively). A greater number of these organisms were found in the 84 smokers with chronic sinusitis than in the nonsmokers (p < 0.01, p < 0.025, and p < 0.001, respectively). Eighty-five BLPB isolates were recovered from 73 patients (30%) with acute sinusitis. These included Moraxella catarrhalis, S aureus, Haemophilus influenzae, Prevotella spp, and Fusobacterium spp; 40 BLPB isolates were found in smokers, and 45 in nonsmokers (p < 0.05). One hundred twenty-five BLPB isolates were recovered from 91 patients (43%) with chronic sinusitis, including M catarrhalis, Bacteroides fragilis group, S aureus, H influenzae, Prevotella spp. and Fusobacterium spp; 69 BLPB isolates were found in smokers, and 56 in nonsmokers (p < 0.001). Antimicrobial therapy had been administered in the past month to 130 patients (28%; 60 smokers and 70 nonsmokers; p < 0.025). Both MRSA and BLPB were isolated more often from these individuals (p < 0.025). However, the higher isolation rates of MRSA and BLPB in smokers were independent of previous antimicrobial therapy.

Conclusions:

These data illustrate a greater frequency of isolation of S aureus, MRSA, and BLPB in patients with acute and chronic sinusitis who smoke.

The impact of smoking on oral and nasopharyngeal bacterial flora

Exposure to direct and passive tobacco smoking has significant impact on the gingival and oropharyngeal flora. The effects of exposure to smoking are evident in both children as well as adults. It increases the acquisition of periodontal pathogens and periodontal disease, colonization by respiratory pathogens, and the occurrence of upper respiratory tract infections, including otitis media. The flora of smokers contains fewer aerobic and anaerobic organisms with interfering activity against bacterial pathogens and harbors more potential pathogens as compared with the flora of non-smokers. The high number of pathogens and the low number of interfering organisms found in the nasopharynx of smokers revert to normal levels after complete cessation of smoking. Since parents who smoke harbor more potential pathogens and fewer interfering organisms, they may serve as a source of pathogens that can colonize and/or infect their children. The reduction in the number of members of the normal flora that interfere with the growth of pathogens and the greater adherence of bacterial pathogens to the oral mucosa are associated with the greater frequency of respiratory infections. Analysis of the data presented illustrates the adverse effects of direct and indirect exposure to smoking on colonization with potential pathogens.

Effects of exposure to smoking on the microbial flora of children and their parents

This review presents our studies that investigated the effects of exposure to direct and indirect smoking on the colonization with pathogenic bacteria and organisms that interfere with their growth. The flora of smokers (S) contained less aerobic and anaerobic organisms with interfering capability and more potential pathogens as compared with non-smokers (N-S). The high number of pathogens and the low number of interfering organisms found in the nasopharynx of smokers revert to normal levels after complete cessation of smoking. A high recovery rate of potential pathogens and low number of interfering organisms were observed in otitis media prone (OMP) children. This was not related to their parents smoking habits. The flora of S parents contains more potential pathogens that are similar to the one recovered from their OMP children, and less interfering organisms as compared to N-S parents. Parents that smoked were more often colonized by potential pathogens than parents that did not smoke. The flora of healthy children of S parents contained high number of potential pathogens similar to the one found in their parents and OMP children. Concordance with pathogens in the parent was high among the OMP children of S parents but this was not observed in OMP children of N-S. A higher recovery rate of potential pathogenic organisms was observed in OMP children of both S and N-S parents, as compared to healthy children whose parents were N-S. Since S parents harbor more potential pathogens and less interfering organisms they may serve as a source of pathogens that can colonize and/or infect their children. These studies illustrate the adverse effects of direct and indirect exposure to smoking on colonization with potential pathogens.

Tobacco use increases susceptibility to bacterial infection

Active smokers and those exposed to secondhand smoke are at increased risk of bacterial infection. Tobacco smoke exposure increases susceptibility to respiratory tract infections, including tuberculosis, pneumonia and Legionnaires disease; bacterial vaginosis and sexually transmitted diseases, such as chlamydia and gonorrhoea; Helicobacter pylori infection; periodontitis; meningitis; otitis media; and post-surgical and nosocomial infections. Tobacco smoke compromises the anti-bacterial function of leukocytes, including neutrophils, monocytes, T cells and B cells, providing a mechanistic explanation for increased infection risk. Further epidemiological, clinical and mechanistic research into this important area is warranted.

Recovery of Potential Pathogens and Interfering Bacteria in the Nasopharynx of Smokers and Nonsmokers

BACKGROUND

Active smoking and passive exposure to cigarette smoke are associated with colonization by some potentially pathogenic species of bacteria and an increased risk of respiratory tract infection in both adults and children. In an attempt to explain these observations, this study compared the frequency of isolation of potential pathogens, and aerobic and anaerobic bacteria that possess interfering capabilities (ie, interfering with the in vitro growth of potential pathogens) in the nasopharynx of smokers to their recovery in nonsmokers.

METHODS

Nasopharyngeal specimens for cultures were taken from 20 smokers and 20 nonsmokers. Potential pathogens, and aerobic and anaerobic bacteria with interfering capabilities against these organisms were identified.

RESULTS

Fourteen potential pathogens (0.7 per patient) were isolated from nasopharyngeal cultures obtained from 11 of the 20 smokers, and 4 (0.2 per patient) were recovered from 3 of the 20 nonsmokers (p < 0.01). In vitro bacterial interference between two aerobic (alpha-hemolytic and nonhemolytic streptococci) and two anaerobic species (Prevotella and Peptostreptococcus species), and four potential pathogens (Streptococcus pneumoniae, Haemophilus influenzae [non-type b], Moraxella catarrhalis, and Streptococcus pyogenes) was observed. Bacterial interference was noted in 61 instances against the four potential pathogens by 22 normal flora isolates that were recovered from the group of smokers, and in 155 instances by 50 isolates from the group of nonsmokers (p < 0.01).

CONCLUSIONS

These findings illustrate for the first time that the nasopharyngeal flora of smokers contains fewer aerobic and anaerobic organisms with interfering capabilities and more potential pathogens compared with those of nonsmokers.