Association of adenoid hyperplasia and bacterial biofilm formation in children with adenoiditis in Taiwan

Biofilm formation and molecular analysis of intercellular adhesion gene cluster (icaABCD) among Staphylococcus aureus strains isolated from children with adenoiditis

Background and Objectives:

It is well known that Staphylococcus aureus biofilm plays an important role in adenoiditis and biofilm resistance frequently results in failure of therapy. The goal of this study was to evaluate the biofilm production of S. aureus isolates obtained from adenoid specimens and assess the relationship between biofilm formation ability and ica operon genes.

Materials and Methods:

A total of 112 adenoid samples were obtained from patients under 15 years old with adenoid hypertrophy. All S. aureus isolates were initially identified by standard microbiological tests and amplification of nuc by polymerase chain reaction (PCR) technique. Biofilm formation of S. aureus isolates was evaluated and icaADBC genes were detected by PCR technique.

Results:

There were 46 isolates (41%) identified as S. aureus. The ability to produce biofilm was detected among total S. aureus isolates. Molecular study of ica operon revealed that 2 (6.3%) and 19 (59.4%) isolates carried icaA and icaD, respectively. The prevalence of icaA + icaD was seen among 11 (34.4%) S. aureus isolates, while icaC and icaB were not detected.

Conclusion:

Our findings indicated that icaABCD operon are associated with biofilm formation in S. aureus isolates, however the absence of these genes may not necessarily exclude this property.

Extract of Pyrus nivalis enhances phagocytosis in lungs after particles matter exposure in BALB/c mice

During past few decades, studies have demonstrated that particulate matter (PM) is the most serious environmental pollutant in industrial countries which mainly contributes for increasing prevalence of chronic respiratory inflammatory diseases. Healthy food supplements to prevent the inflammatory diseases are common and show notable effects. The effects of the extract of Pyrus nivalis, a common fruit and herbal medicine in Taiwan, on PM-induced airway inflammation in mice were investigated by feeding the extract orally for 21 days. Results obtained from lung histology and bronchial alveolar lavage fluid (BALF) cell profile showed that oral feeding of P. nivalis extract did not affect the airway inflammation. However, it increased the phagocytic activity in BALF cells and induced M1-dominant macrophage differentiation in lungs. Our study showed that extract of P. nivalis might present the beneficial and therapeutic potential for clearance of PM and pathogens in airway. PRACTICAL APPLICATIONS: Pyrus nivalis is a common fruit and also used extensively in Chinese herbology. The pharmacological effects of P. nivalis have been reported in ancient Chinese Medical literature and known to possess anti-asthma and anti-cough properties as well as to enhance function of lungs. In this study, we found that orally feeding the extract of P. nivalis did not induce airway inflammation and affect particulate matter (PM)-induced inflammatory cells infiltration in lungs but increased phagocytosis with or without PM treatment which might indicate its therapeutic potential for clearance of PM and pathogens in airway.

Adenoidal Disease and Chronic Rhinosinusitis in Children-Is there a Link?

Adenoid hypertrophy (AH) is an extremely common condition in the pediatric and adolescent populations that can lead to various medical conditions, including acute rhinosusitis, with a percentage of these progressing to chronic rhinosinusitis (CRS). The relationship between AH and pediatric CRS has been extensively studied over the past few years and clinical consensus on the treatment has now been reached, allowing this treatment to become the preferred clinical practice. The purpose of this study is to review existing literature and data on the relationship between AH and CRS and the options for treatment. A systematic literature review was performed using a search line for "(Adenoiditis or Adenoid Hypertrophy) and Sinusitis and (Pediatric or Children)". At the end of the evaluation, 36 complete texts were analyzed, 17 of which were considered eligible for the final study, dating from 1997 to 2018. The total population of children assessed in the various studies was of 2371. The studies were categorized as surgical-observational, microbiological, genetic-immunological, and radiological. The analysis of the studies confirms the relationship between AH and CRS and supports the existing consensus on medical and surgical therapy. Furthermore, these studies underline the necessity to adapt medical and surgical treatment considering age, comorbidities including asthma and, if present, the Computed Tomography (CT) score.

Paired analysis of the microbiota between surface tissue swabs and biopsies from pediatric patients undergoing adenotonsillectomy

INTRODUCTION

Culture-independent methods, based on bacterial 16 S rRNA gene sequencing, have been used previously to investigate the adenotonsillar microbiota. However, these studies have focused on a single sampling site (usually a surface swab). We aimed to investigate potential differences in adenotonsillar microbiota according to sampling location, both on and within the adenoids and palatine tonsils.

METHODS

Pediatric patients (n = 28, mean age five years) undergoing adenotonsillectomy were recruited for this study. At the time of surgery, a mucosal adenoid surface swab and an adenoid tissue biopsy was collected. Immediately following surgery, the crypts of the right and left tonsils were swabbed, and a surface and core tissue sample from the right tonsil were also collected. Bacterial 16 S rRNA gene-targeted amplicon sequencing was used to determine the bacterial composition of the collected samples.

RESULTS

There was no significant difference in diversity or composition of the adenoid microbiota based on sampling site. However, the Shannon-Wiener and Inverse-Simpson diversity indices differed significantly (p < 0.05) between the microbial communities of the three different tonsil sampling sites. There was a higher average relative abundance of members from the genera Streptococcus, Actinobacillus, and Neisseria in the tonsil crypts when compared with surface and core tonsil tissue samples.

CONCLUSION

Our results indicate that there is variation in bacterial diversity and composition based on sampling sites in the tonsils but not the adenoids. The difference in microbiota between the surface and the tissue may have implications for our understanding of the pathogenesis of recurrent tonsillitis and have treatment implications.

Is there any association between adenoid biofilm and upper airway infections in pediatric patients?

Aim

To evaluate the association of the presence and extent of adenoid biofilms and the frequency of upper airway infections in children with upper airway obstruction.

Material and Methods

This cross-sectional study was conducted from October 2014 to December 2015 on pediatric patients who were candidates for adenoidectomy due to obstructive sleep apnea. After removal of the adenoid tissue and fixation in 2.5% glutaraldehyde, the samples were sent to the electron microscopy unit. The extent of biofilm formation was examined using environmental scanning electron microscopy. These results were then confirmed using image analysis software.

Results

Fifty-seven children with a mean age of 7.31 (±2.65) years were included in the study. Forty-three (75.4%) were male and 14 (24.6%) were female. The average number of upper airway infections during the last 12 months before adenoidectomy was 10.01 (±5.38). Biofilm structures were detected in all (100%) samples. As the main outcome, the extent of biofilm grading exhibited a statistically significant correlation with the frequency of upper airway infections (p<0.001). There was no significant correlation between sex and adenoid size with the biofilm extent.

Conclusion

The present study showed that the extent of adenoid biofilm had a significant relationship with the frequency of upper airway infection rate. It seems that the presence of a biofilm on the adenoid surface as a reservoir for microorganisms could cause chronic inflammation.

Adenoidectomy May Not Be Effective to Reduce the Number of Hospital Visits for Sinusitis

BACKGROUND

The objective of this study was to compare post-operative (post-op) visits for sinusitis between adenoidectomy and non-adenoidectomy participants (control).

METHODS

Using the national cohort study from the Korean Health Insurance Review and Assessment Service, we used 1:4 matching to select 2,593 adenoidectomy participants and 10,372 control participants. Post-op visits for sinusitis were measured from post-op 1 year through post-op 9 years. Equivalence testing was used. Margin of equivalence of difference was set as -0.5 to 0.5 in this study.

RESULTS

There were trivial differences between the two groups from post-op 1 to 2 years. However, there was no difference between the two groups from post-op 3 through 9 years. Visits for sinusitis gradually decreased in both groups. In the rare and frequent pre-operative sinusitis group, there were minor differences in both groups from post-op 1 to 2 years. In contrast, there were no differences between the two groups in rare and frequent pre-operative sinusitis groups from post-op 3 through 9 years. In the 0-4 years old group, there were minor differences between both groups from post-op 1 to 2 years. However, no differences in the number of visits for sinusitis were found between the two groups during follow up periods from post-op 3 through 9 years. Additionally, there were no differences between the two groups during the entire follow up period.

CONCLUSION

Adenoidectomy does not reduce post-op visits for sinusitis. Sinusitis decreased over time whether adenoidectomy was performed or not.

Halitosis in children with adenoid hypertrophy

This paper attempts to identify the sources and evaluate the prevalence of halitosis in children with adenoid hypertrophy. The study included pediatric patients admitted for adenoidectomy due to obstructive symptoms. Patients with possibly other causes of halitosis, were excluded from the study. Halitosis was detected in 30 out of 136 children (22.1%). The effect of adenoid hypertrophy on halitosis was confirmed by the significant reduction in the organoleptic score rated according to the Rosenberg scale (on average by 2°) and the levels of volatile sulfur compounds (on average 84 ppb) post-adenoidectomy, as compared to pre-surgery results. In total, we reported a statistically significant decrease in the abovementioned values in 90% of patients with halitosis. It was found that in patients with halitosis, as compared to patients with no oral malodor, anaerobic bacteria and Staphylococcus aureus were more frequently observed in the adenoid tissue. Streptococcus oralis strains were more commonly reported in the material taken during adenoidectomy in children without oral malodor.

[The possibilities for the rational pharmacotherapy of adenoiditis in the children]

The available literature data give evidence that viral infection is the main cause underlying the development of inflammatory nasopharyngeal pathology in the children. According to ICD-10, nether acute nor chronic adenoiditis should be considered as a self-consistent nosological entity. Acute adenoiditis is usually regarded as a form of acute nasopharyngitis (J02) or acute respiratory viral infection (J06.9) whereas chronic adenoiditis is commonly referred to as representing other chronic diseases of the tonsils and adenoids (J 35.8). The reactive changes in the nasopharyngeal tonsils begin to be manifested on days 3-5 after the onset of acute respiratory viral infection; thereafter, they persist and gradually disappear within the next 2-3 weeks. In the majority of the cases, acute adenoiditis is actually a physiological reaction of the nasopharyngeal tonsils as the organs of regional mucosal immunity to antigenic stimulation. There is no universally accepted opinion as regards the duration of the inflammatory process which would allow these pathological changes to be considered as turned into chronic ones. This condition is actually not a serious pathology provided it is not associated with the concomitant complications and produces no clinically significant effect on the child's quality of life. Under practical conditions, such children are most frequently treated with the use of irrigation therapy. Taking into account that otorhinolaryngologists all over the world do not consider chronic adenoiditis as an independent nosological entity but distinguish only hypertrophy of adenoid vegetations or chronic rhinosinusitis (in the presence of inflammatory changes in the nasopharynx), it appears correct to speak about chronic adenoiditis provided the clinical manifestations of the disease persist for more than 12 weeks. Based on the predominant etiological component, the viral, bacterial, and allergic forms of nasopharyngeal adenoiditis can be distinguished even though it is rather difficult to actually determine which etiological factor prevails in each concrete case. The aforedescribed situation poses a large number of questions pertaining to the choice of either systemic or topical antibacterial therapy.

Interleukin-13 Inhibits Lipopolysaccharide-Induced BPIFA1 Expression in Nasal Epithelial Cells

Short palate, lung, and nasal epithelium clone 1 (SPLUNC1) protein is expressed in human nasopharyngeal and respiratory epithelium and has demonstrated antimicrobial activity. SPLUNC1 is now referred to as bactericidal/permeability-increasing fold containing family A, member 1 (BPIFA1). Reduced BPIFA1 expression is associated with bacterial colonization in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). Interleukin 13 (IL-13), predominately secreted by T helper 2 (T_H2) cells, has been found to contribute to airway allergies and suppress BPIFA1 expression in nasal epithelial cells. However, the molecular mechanism of IL-13 perturbation of bacterial infection and BPIFA1 expression in host airways remains unclear. In this study, we found that lipopolysaccharide (LPS)-induced BPIFA1 expression in nasal epithelial cells was mediated through the JNK/c-Jun signaling pathway and AP-1 activation. We further demonstrated that IL-13 downregulated the LPS-induced activation of phosphorylated JNK and c-Jun, followed by attenuation of BPIFA1 expression. Moreover, the immunohistochemical analysis showed that IL-13 prominently suppressed BPIFA1 expression in eosinophilic CRSwNP patients with bacterial infection. Taken together, these results suggest that IL-13 plays a critical role in attenuation of bacteria-induced BPIFA1 expression that may result in eosinophilic CRSwNP.

Association of β-Lactam-Sensitive Haemophilus influenzae Type B with Adenoid Biofilm Formation in Patients with Adenoidectomy Surgery

BACKGROUND

Chronic adenoid infection by β-lactam-resistant Haemophilus influenzae type b (Hib) and biofilm formation contribute to adenoid hyperplasia. Middle ear disease consequently remains a critical issue in the pediatric population. The aim of this study was to investigate the correlation of Hib biofilm formation with middle ear effusion with adenoid hyperplasia (MEE-AH) and with pediatric obstructive sleep apnea (OSA).

METHODS

A total of 384 patients with adenoidectomy from January 2008 to December 2012 were recruited in this investigation. Thirty-two patients (14 female and 18 male; age 4-13 years) who obtained routine adenoidectomy surgery had Hib-positive cultures were enrolled in a retrospective manner. By using polysomnography, 18 patients were diagnosed as having MEE-AH with chronic adenotonsillitis, and 14 patients were diagnosed as having pediatric OSA. The results of the Hib biofilm, antibiotic resistance profiles, and scanning electron microscopy observation, which correlated with the clinical diagnosis, were analyzed by the chi-square test and Fisher exact test.

RESULTS

Biofilm formation by Hib was significantly present in the patients with MEE-AH rather than patients with OSA. β-lactam-sensitive Hib were resistant to augmentin because of the adenoid biofilm formation. However, this finding was uncommon in the pediatric OSA group.

CONCLUSIONS

Properly treating β-lactam-sensitive Hib infection may be an important issue in reducing MEE-AH and adenoid vegetation in the pediatric population. Further research is warranted to elucidate the association of Hib-related biofilm formation with treatment failure and the need to consider earlier surgical intervention.

Biofilm formation on tympanostomy tubes depends on methicillin-resistant Staphylococcus aureus genetic lineage

Bacterial biofilm formation has been implicated in the high incidence of persistent otorrhoea after tympanostomy tube insertion. The aim of the study was to investigate whether biofilm formation on tympanostomy tubes depends on the genetic profile of methicillin-resistant Staphylococcus aureus (MRSA) strains. Capacity of biofilm formation on fluoroplastic tympanostomy tubes (TTs) was tested on 30 MRSA strains. Identification and methicillin resistance were confirmed by PCR for nuc and mecA genes. Strains were genotypically characterised (SCCmec, agr and spa typing). Biofilm formation was tested in microtiter plate and on TTs. Tested MRSA strains were classified into SCCmec type I (36.7 %), III (23.3 %), IV (26.7 %) and V (13.3 %), agr type I (50 %), II (36.7 %) and III (13.3 %), and 5 clonal complexes (CCs). All tested MRSA strains showed ability to form biofilm on microtiter plate. Capacity of biofilm formation on TTs was as following: 13.3 % of strains belonged to the category of no biofilm producers, 50 % to the category of weak biofilm producers and 36.7 % to moderate biofilm producers. There was a statistically significant difference between CC, SCCmec and agr types and the category of biofilm production on TTs tubes (p < 0.001): CC5, SCCmecI type and agrII type with a moderate amount of biofilm, and CC8 and agrI type with a low amount of biofilm. Biofilm formation by MRSA on TTs is highly dependent on genetic characteristics of the strains. Therefore, MRSA genotyping may aid the determination of the possibility of biofilm-related post-tympanostomy tube otorrhea.

The bacterial interactions in the nasopharynx of children receiving adenoidectomy

Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae are the common pathogens that colonize in the nasopharynx of children. Polymicrobial interactions are thought to play an important role in different sites throughout the human body. However, there are currently very few studies that investigate the interactions between S. aureus, S. pneumoniae, and H. influenzae in the nasopharynx. We retrospectively analyzed the adenoid tissue culture from 269 children who received adenoidectomy. S. aureus, S. pneumoniae, and H. influenzae constituted the major microorganisms which were cultured from these adenoidectomies, at 23.4%, 21.6%, and 18.2%, respectively. S. pneumoniae and H. influenzae were the most prevalent in the preschool-aged children (3 < age ≤ 6), whereas S. aureus was more prevalent in infants and toddlers (age ≤ 3) and school-aged children (age > 6). Bacterial interference was found between S. aureus and S. pneumoniae and between S. aureus and H. influenzae, whereas there was an association found between S. pneumoniae and H. influenzae. The synergism and antagonism among these three species are investigated in the following paper, with the possible mechanisms involved in these interactions also discussed.

Decreased PLUNC expression in nasal polyps is associated with multibacterial colonization in chronic rhinosinusitis patients

PLUNC (palate, lung, and nasal epithelium clone) is an epithelium-secreted protein that plays a crucial role in the host's defense against bacterial infection. The function of PLUNC in the sinus remains poorly understood. To examine whether the expression levels of PLUNC could serve as a predictive outcome biomarker for patients with CRSwNP and bacterial colonization, we investigated the association of PLUNC expression levels with bacterial colonization in the sinuses. A total of 174 patients who underwent sinus surgery for chronic rhinosinusitis with nasal polyps (CRSwNP) were enrolled in this study. The tissue samples obtained from patients were examined using preoperative sinus computed tomography (CT) scans, postoperative bacterial cultures, and nasal polyp examinations. PLUNC mRNA and protein expression were quantified using RT-PCR and immunohistochemistry. We identified that decreased PLUNC expression is associated with multibacterial colonization (P = 0.0001), specifically those mediated by Staphyloccocus aureus (P = 0.037) and Pseudomonas aeruginosa (P = 0.002). The patients who required repeated sinus surgeries for recurrent or persistent sinusitis also presented much lower PLUNC expression than those who did not require repeated sinus surgery (P = 0.001). However, gender, age, and CT scores were not associated with PLUNC expression. These results suggest that reduced PLUNC expression is associated with bacterial colonization as well as treatment outcome in CRSwNP patients. Investigation of the association between PLUNC expressions and chronic rhinosinusitis may lead to the development of a novel biomarker for treatment outcome in CRSwNP patients.

Biofilm Formations in Nasopharyngeal Tissues of Patients with Nasopharyngeal Osteoradionecrosis

Objective

Determine the presence of nasopharynx biofilms in patients with nasopharyngeal cancer (NPC) and osteoradionecrosis (ORN) and patients with NPC but no ORN.

Study Design

Cross-sectional study.

Setting

Tertiary referral medical center.

Subjects and Methods

We enrolled 27 patients with NPC from our outpatient clinic during January 2010 to June 2012. These patients were diagnosed with NPC between 1980 and 2012, and all had received radiotherapy. Of these 27 patients, 15 presented with ORN, and 12 did not. The nasopharynx biopsied specimens were processed and analyzed within 2 hours of collection with the FilmTracer LIVE_DEAD Biofilm Viability Kit (Molecular Probes, Invitrogen, Carlsbad, California). A blinded investigator determined the formation of biofilms by fluorescence microscopy. Bacterial cultures were collected.

Results

Eleven of 15 (73%) ORN patients had biofilm formations in nasopharynx biopsy specimens. Five of these samples (45%) yielded positive cultures, and 4 of these cultures indicated the presence of methicillin-resistant Staphylococcus aureus (MRSA). Only 1 of 12 NPC patients without ORN had nasopharynx biofilm formation, and all culture results were negative.

Conclusion

Biofilm formations were common in nasopharynx samples of NPC patients with ORN but rare in samples of NPC patients without ORN. The presence of biofilms, especially MRSA, may have a role in the disease progression of ORN or may contribute to the chronicity and resistance to antibiotic treatment.