A review of the association between oral bacterial flora and obstructive sleep apnea-hypopnea syndrome comorbid with cardiovascular disease.

PURPOSE: Obstructive sleep apnea-hypopnea syndrome (OSAHS), a common sleep disorder, has been shown to be an independent risk factor for cardiovascular disease (CVD). Recent studies have focused on the important roles of microorganisms in human health; for example, microorganisms are reportedly associated with obesity, metabolic disorders, and CVD. The number of oral bacteria in patients with OSAHS is considerably higher than that in healthy individuals, and infection with oral bacterial pathogens is associated with the development of CVD. However, whether changes in the oral microbiota mediate the development of OSAHS and CVD remains unknown. METHODS: Therefore, we attempted to review the association between changes in oral microbiota in patients with OSAHS and the development of CVD. RESULTS: Oral microbiota possibly acts via multiple pathways including direct invasion, platelet aggregation, immune response, inflammatory response, and oxidative stress response, leading to the development of CVD in patients with OSAHS. In particular, the strains Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia have demonstrated profound effects. OSAHS leads to changes in the oral bacterial flora and thus may facilitate the occurrence and development of CVD. CONCLUSION: We propose that the underlying mechanism of CVDs resulting from oral microbiota in patients with OSAHS should be elucidated in further studies.

Differential IL-17A response to S. pneumoniae in adenoid tissue of children with sleep disordered breathing and otitis media with effusion.

Streptococcus pneumonia, one of the major colonizers in nasopharyngeal adenoids, has been the predominant pathogen causing acute otitis media (AOM) in children. Recent evidence suggests an association between IL-17A-mediated immune response and the clearance of pneumococcal colonization in nasopharyngeal adenoids. Here, we evaluated the expressions of IL-17A and associated genes in hypertrophic adenoid tissues of children with sleep-disordered breathing (SDB) and otitis media with effusion (OME) and their association with pneumococcal carriage. Sixty-six pediatric patients with adenoid hypertrophy were enrolled. During adenoidectomy, nasopharyngeal swab and adenoid tissues were used to determine pneumococcal carriage and IL-17A expression. Our results revealed significantly higher levels of IL-17A and IL-17A:IL-10 mRNA in the SDB patients positive for nasopharyngeal pneumococcal carriage than those negative. However, these differences were not significant in the OME group. These results suggested, in OME patients, prolonged or chronic pneumococcal carriage may occur because of insufficient IL-17A-mediated mucosal clearance, and could further lead to AOM and OME development.

Role of the Gut Microbiome in Obstructive Sleep Apnea-Induced Hypertension.

Individuals suffering from obstructive sleep apnea (OSA) are at increased risk for systemic hypertension. The importance of a healthy gut microbiota, and detriment of a dysbiotic microbiota, on host physiology is becoming increasingly evident. We tested the hypothesis that gut dysbiosis contributes to hypertension observed with OSA. OSA was modeled in rats by inflating a tracheal balloon during the sleep cycle (10-s inflations, 60 per hour). On normal chow diet, OSA had no effect on blood pressure; however, in rats fed a high-fat diet, blood pressure increased 24 and 29 mm Hg after 7 and 14 days of OSA, respectively (P<0.05 each). Bacterial community characterization was performed on fecal pellets isolated before and after 14 days of OSA in chow and high-fat fed rats. High-fat diet and OSA led to significant alterations of the gut microbiota, including decreases in bacterial taxa known to produce the short chain fatty acid butyrate (P<0.05). Finally, transplant of dysbiotic cecal contents from hypertensive OSA rats on high-fat diet into OSA recipient rats on normal chow diet (shown to be normotensive) resulted in hypertension similar to that of the donor (increased 14 and 32 mm Hg after 7 and 14 days of OSA, respectively; P<0.05). These studies demonstrate a causal relationship between gut dysbiosis and hypertension, and suggest that manipulation of the microbiota may be a viable treatment for OSA-induced, and possibly other forms of, hypertension.

Presence of different genotypes of Helicobacter pylori in patients with chronic tonsillitis and sleep apnoea syndrome.

Helicobacter pylori, a well-known gastric pathogen, has been detected in the oral cavity and oropharynx in tonsillar tissue. In our study, the presence of H. pylori in the tonsillar tissue of patients with chronic tonsillitis and sleep apnoea syndrome (SAS) was investigated. The aim was to detect and genotype H. pylori for a collection of data supporting the possible role of H. pylori in the aetiology of chronic tonsillitis and SAS. Helicobacter pylori was detected by real-time polymerase chain reaction (rt-PCR). 89 patients, 60 with a diagnosis of chronic tonsillitis and 29 with SAS, were tested. In the chronic tonsillitis group, Helicobacter was detected in 48 (80 %) specimens, cagA gene was detected in 12 samples (25 %) and 12 samples were negative. In SAS group, Helicobacter was found in 24 samples (82.76 %), cagA gene was detected in 5 (20.83 %) and 5 samples (17.24 %) were negative. Helicobacter pylori-specific immunoglobulins were tested by ELISA in the serum of 57 patients only with 41 (71.93 %) showing positive. Our results on H. pylori DNA detection and H. pylori seropositivity show 26.32 % discrepancy, slightly in favour of rt-PCR (15.79 % compared to 10.53 %). The H. pylori presence in tonsillar tissue does not depend on the type of oropharyngeal disease (p = 0.756). This study shows that oropharynx constitutes an extragastric reservoir of H. pylori infection which could serve as an aetiopathogenetic factor for chronic tonsillitis and tonsillar hyperplasia by SAS. No conclusion has yet been drawn about the mechanism of the process.

Prevalence of tonsillar Actinomyces in children undergoing tonsillectomy for sleep disordered breathing compared with recurrent tonsillitis.

OBJECTIVE: To determine the prevalence of tonsillar actinomycosis in pediatric tonsillectomies performed for sleep disordered breathing (SDB) compared with recurrent infective tonsillitis. METHODS: All tonsillectomy specimens performed in a pediatric otolaryngology practice over a 10-year period were sent to the same pathology laboratory for histological analysis for the prevalence of Actinomyces. A database of 1213 children was generated and analyzed to determine any significant differences in Actinomyces carriage between children with a primary diagnosis of sleep disordered breathing, compared with recurrent tonsillitis. Statistical analysis was performed using a 2 way contingency table, and significance analyzed via chi-squared and Fisher's exact test. RESULTS: Four hundred and sixty five children aged less than 16 underwent tonsillectomy for recurrent tonsillitis and 748 for SDB. Actinomyces were identified in 68 of the group with recurrent tonsillitis (14.6%) and in 153 of the group with SDB (20.5%). This difference was statistically significant with p=0.009 on two-tail Fisher's exact test. CONCLUSION: There was a statistically significant higher rate of Actinomyces colonization in children undergoing tonsillectomies for SDB compared to recurrent tonsillitis.

Helicobacter pylori seroprevalence in patients with obstructive sleep apnea syndrome among a Chinese population.

OBJECTIVE: To investigate the seroprevalence of Helicobacter pylori (H. pylori) in patients with obstructive sleep apnea syndrome (OSAS), and to determine any association between H. pylori infection and severity of OSAS. METHODS: Two hundred and forty-three subjects were recruited in this cross-sectional study at the Department of Respiratory Medicine in the West China Hospital, Sichuan, P. R. China, from October 2006 to April 2008. Polysomnography (PSG) was used to determine the apnea-hypopnea index (AHI), and enzyme-linked immunosorbent assay was used to test H. pylori IgG. According to the AHI, subjects were divided into 4 groups: the control group (AHI < 5/hours), patients with mild OSAS group (AHI: 5-14/hours), moderate OSAS group (AHI: 15-29/hours), and severe OSAS group (AHI: > or = 30/hours). RESULTS: The prevalence of H. pylori infection in patients with OSAS was 75.5%, and in the controls it was 53.4% (p=0.000). The prevalence of H. pylori infection in patients with mild OSAS was 57.1%, with moderate OSAS was 76.5%, and with severe OSAS was 90.9%. There were significant differences between patients with moderate and severe OSAS and the controls, as well as among the mild, moderate, and severe OSAS groups. CONCLUSION: Helicobacter pylori infection may be associated with OSAS. In addition, increased severity of OSAS might be associated with higher seroprevalence of H. pylori.

Actinomycetes colonization of tonsils: a comparative study between patients with and without recurrent tonsillitis.

OBJECTIVE: To determine the prevalence of tonsillar actinomycetes colonization in patients with and without recurrent tonsillitis and to study the association of this condition with recurrent tonsillitis and tonsillar hypertrophy. STUDY DESIGN AND SETTING: A retrospective study of 834 patients who had undergone tonsillectomy for recurrent tonsillitis (group A) and for sleep-disordered breathing without a history of recurrent tonsillitis (group B). RESULTS: The prevalence of tonsillar actinomycetes colonization was higher in patients who had undergone tonsillectomy for sleep-disordered breathing (44.1 per cent) than in patients who had undergone tonsillectomy for recurrent tonsillitis (33.3 per cent). The prevalence did not differ by sex or age of patient, although the occurrence rate was higher in the adult compared with the paediatric population. There was no statistically significant difference between the mean size of the tonsils removed in the two groups, and actinomycetes colonization did not affect tonsil size. Histopathological analysis of resected tonsils did not show active tissue infection. CONCLUSION: The presence of actinomyces does not indicate active disease. We are of the opinion that, although actinomyces colonization is more prevalent in patients with sleep-disordered breathing, it does not contribute to tonsillar hypertrophy nor to recurrent tonsillitis.

Tonsillar microbial flora: comparison of recurrent tonsillitis and normal tonsils.

Tonsillar microbial flora was studied in cultures of tonsillar core specimens from 34 patients tonsillectomized due to recurrent group A streptococcal pharyngotonsillitis (n = 17) or sleep apnoea (n = 17). Patients in the sleep apnoea subgroup, who had no history of recurrent tonsillitis and manifested no tonsillar hypertrophy at ENT examination, served as controls. Tonsillar core specimens were cultured for semi-quantitative estimation of growth of aerobic, anaerobic and facultative organisms. The recurrent tonsillitis and apnoea subgroups did not differ significantly in the mean number of isolates per patient, either of aerobic spp. (3.8 vs. 4.3) or anaerobic spp. (5.2 vs. 4.7). Nor did the two subgroups differ significantly in the proportion of patients whose specimens manifested beta-lactamase producers (71% vs. 59%), in the isolation frequency of viridans (alpha) streptococci, or in the occurrence of semi-quantitative growth estimates of 3-4+ for aerobic, anaerobic or beta-lactamase-producing spp. Thus, the study provided no support for the hypothesis that inactivation of penicillin V by beta-lactamase-producing bacteria in oral or throat flora, or the eradication of viridans streptococci with their GAS-inhibitory capacity, is an important factor with regard to recurrent group A streptococcal tonsillitis. Other possible explanations, such as poor antibiotic penetration at the site of infection, are discussed.

[Microbiological studies of a nasal positive pressure respirator with and without a humidifier system]. / Mikrobiologische Untersuchungen eines nasalen Uberdruckatmungssystems ohne und mit Benutzung eines Befeuchtersystems.

13 patients with obstructive sleep apnea syndrome treated with CPAP-therapy and complicating affections of the nasal and pharyngeal mucosa were enrolled in a randomized cross-over study comparing therapy with a heated humidifier (HC 100, company Fisher & Paykel) and treatment with a heat and moisture exchanger (Typ I, company Dahlhausen). We assessed the bacterial and fungal colonisation of the nasal masks of all patients. Samples of mask rinses were taken after the two treatment periods (2 weeks each) and the period without humidification in between. All microbes were found to have pathological potency. There was no significant difference in the total concentration of the microbes in the different treatment modalities. In a few cases however, gram negative bacteria were detected on the masks during humidification with a heated humidifier, but not with heat and moisture exchangers. Legionella spec. were not detectable in any of the samples. Candida albicans was the only fungus detectable. No patient had any infection of the upper or lower respiratory system associated with humidification therapy.