Human Palatine Tonsils Are Linked to Alzheimer’s Disease through Function of Reservoir of Amyloid Beta Protein Associated with Bacterial Infection

Amyloid-β (Aβ)-peptide production or deposition in the neuropathology of Alzheimer’s disease (AD) was shown to be caused by chronic inflammation that may be induced by infection, but the role of pathogenic-bacteria-related AD-associated Aβ is not yet clearly understood. In this study, we validated the hypothesis that there is a correlation between the Aβ-protein load and bacterial infection and that there are effects of bacteria, Staphylococcus aureus (S. aureus), on the Aβ load in the inflammatory environment of human tonsils. Here, we detected Aβ-peptide deposits in human tonsil tissue as well as tissue similar to tonsilloliths found in the olfactory cleft. Interestingly, we demonstrated for the first time the presence of Staphylococcus aureus (S. aureus) clustered around or embedded in the Aβ deposits. Notably, we showed that treatment with S. aureus upregulated the Aβ-protein load in cultures of human tonsil organoids and brain organoids, showing the new role of S. aureus in Aβ-protein aggregation. These findings suggest that a reservoir of Aβ and pathogenic bacteria may be a possible therapeutic target in human tonsils, supporting the treatment of antibiotics to prevent the deposition of Aβ peptides via the removal of pathogens in the intervention of AD pathogenesis.

Coblation Versus Bipolar Diathermy Hemostasis in Pediatric Tonsillectomy Patients: Systematic Review and Meta-Analysis

This study aimed to compare the outcomes of coblation versus bipolar diathermy in pediatric patients undergoing tonsillectomy. A systematic review and meta-analysis were performed per the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Guidelines. An electronic search of information was conducted to identify all Randomized Controlled Trials (RCTs) comparing the outcomes of coblation versus bipolar in pediatric patients undergoing tonsillectomy. Primary outcome measures were intraoperative bleeding, reactionary hemorrhage, delayed hemorrhage, and post-operative pain. Secondary outcome measures included a return to a normal diet, effects on the tonsillar bed, operation time, and administration of analgesia. Fixed and random-effects models were used for the analysis. Seven studies enrolling 1328 patients were identified. There was a significant difference between coblation and bipolar groups in terms of delayed hemorrhage (Odds Ratio [OR] = 0.27, P = 0.005) and post-operative pain (standardized mean difference [MD] = -2.13, P = 0.0007). Intraoperative bleeding (MD = -43.26, P = 0.11) and reactionary hemorrhage did not show any significant difference. The coblation group improved analgesia administration, diet and tonsillar tissue recovery, and thermal damage for secondary outcomes. No significant difference was reported in terms of operation time. In conclusion, coblation is comparable to a bipolar technique for pediatric patients undergoing tonsillectomy. It improves postoperative pain and delayed hemorrhage and does not worsen intraoperative bleeding and reactionary hemorrhage.

Impact of Superantigen-Producing Bacteria on T Cells from Tonsillar Hyperplasia

Staphylococcus aureus and Group A Streptococcus (GAS) are common occupants of the tonsils and many strains produce potent exotoxins (mitogens) that directly target T cells, which could be a driver for tonsillar hyperplasia. Tonsil tissues from 41 patients were tested for these bacteria in conjunction with profiling of B and T cells by flow cytometry. S. aureus and GAS were detected in tonsil tissue from 44% and 7%, respectively, of patients by bacteriological culture; immuno-histology showed bacteria in close proximity to both B and T lymphocytes. The presence of tonsillar S. aureus did not alter B or T cell populations, whereas peripheral blood mucosal-associated invariant T (MAIT) cells were significantly increased in S. aureus culture positive individuals (p < 0.006). Alterations of tonsil CD4⁺ TCR Vβ family members relative to peripheral blood were evident in 29 patients. Three patients had strong TCR Vβ skewing indicative of recent exposure to superantigens, their tonsils contained mitogenic bacteria, and supernatants from these bacteria were used to partially recapitulate the skewing profile in vitro, supporting the notion that superantigens can target tonsillar T cells in situ. Tonsils are a reservoir for superantigen-producing bacteria with the capacity to alter the composition and function of key immune cells.

The bacterial community and local lymphocyte response are markedly different in patients with recurrent tonsillitis compared to obstructive sleep apnoea

INTRODUCTION

Obstructive sleep apnea (OSA) is now a more common indication for tonsillectomy than recurrent tonsillitis (RT) [1,2]. Few studies have addressed possible differences in pathogenesis between these two conditions. Children with RT and OSA are often being treated in the community with multiple courses of antibiotics before surgery. Current understanding of the role of bacteria in disorders of the tonsils is mainly based on the culture of tonsil swabs. Swab cultures reflect only a very small fraction of the bacteria present on the mucosal surface and may not represent the bacterial communities within the tonsil crypts [3,4]. This study aimed to evaluate the local lymphocyte response and associations with bacterial community composition using molecular techniques of the tonsils removed from children for RT or OSA.

METHOD

The palatine tonsils were removed by extracapsular dissection from 24 patients with age range one to ten years, 14 of whom had RT and 10 had OSA. The fixed tonsil tissues were evaluated for bacteria by Gram-staining and presence of connective tissue by safranin staining. B lymphocytes and T lymphocytes were also measured immunohistochemically. Finally, previously published bacterial community data for this cohort were reassessed for associations with RT and OSA, and with the observed lymphocyte patterns.

RESULTS

In tonsils from patients with RT, large micro-colonies of bacteria were observed in the tonsil crypts, and a large number of B and T lymphocytes were noted immediately adjacent to the tonsil crypt itself. In marked contrast, the tonsils from patients with OSA had no bacteria identified, and no significant skewing of lymphocytes based on site (such as follicles or crypts). We observed that the majority of lymphocytes surrounding the bacterial micro-colonies were B lymphocytes with a mean ratio of 109:55 (B lymphocytes: T lymphocytes). Bacterial community diversity was not different between the two cohorts; however, there were significant differences in bacterial community composition. Children with RT had a higher relative abundance of members from the genera Parvimonas, Prevotella, and Treponema. While children with OSA had a higher relative abundance of Haemophilus, and Capnocytophaga.

CONCLUSION

These results demonstrate significant differences in the local lymphocyte response and bacterial community composition in tonsil tissue between RT and OSA patients. It suggests that the response to antibiotics used in the treatment of these two conditions may be different. Furthermore, the presence of lymphocytes in RT within the tonsil crypt outside the tonsil epithelium is a unique observation of the location of these cells.

Microbiological Profile of Chronic Tonsillitis in the Pediatric Age Group

Introduction

Tonsillitis is a very common disease in children. Understanding the microbiology and pathology of chronic tonsillitis is an important step in its management. The aim of the study was to describe the microbiological profile of core tonsillar tissue in chronic tonsillitis in children.

Materials and methods

Children under 16 years of age with chronic tonsillitis were recruited in the descriptive study. Children with recurrent tonsillitis and recurrent tonsillitis with obstructive symptoms were included. Children who underwent tonsillectomy for obstructive symptoms alone and those who received antibiotics for at least one month prior to surgery were excluded from the study. Dissection and the snare method of tonsillectomy were done on all children. The operated specimen was cut into two halves in a sterile container. The core of the tonsillar tissue was swabbed with two sterile cotton-tipped swabs and sent for the microbiological evaluation of aerobes and anaerobes. The tonsillar tissue was sent for a histopathological examination.

Results

A total of 106 children were operated for chronic tonsillitis in one year. The mean age of children included in this study was 9.4 years. The duration of symptoms due to tonsillar disease ranged from four weeks to 28 months. There were 48 males and 58 females. Recurrent tonsillitis was the most common indication for tonsillectomy in all children. A total of 301 aerobes and 171 anaerobic microorganisms were isolated from 106 children with chronic tonsillitis. The aerobic bacterial species most often isolated was Streptococcus viridans, which was present in 83 children followed by Group A, β-hemolytic Streptococci in 67 children. The anaerobic bacterial most often isolated was Peptococcus species in 49 children. Polymicrobial aerobic and anaerobic flora were present in all tonsillar specimens, yielding an average of 4.1 isolates per specimen. The histopathological examination revealed chronic tonsillitis with reactive follicular hyperplasia in all (100%) children. Actinomycosis was associated with non-specific reactive follicular hyperplasia in four specimens.

Conclusion

Polymicrobial aerobic and anaerobic flora are identified in deep tonsillar tissue in children with tonsillitis. The identification of bacterial isolates from the core tissue in recurrent tonsillitis could dictate the management of chronic tonsillitis. The histopathological examination of the core tissues of the tonsils helps in an accurate identification of organisms that are difficult to culture.

[The specific features of the past medical history and etiology of pharyngeal abscess in the children]

The present study was undertaken for the purpose of elucidating the specific features of the past medical history and the etiological factors responsible for the development of tonsillogenic pharyngeal abscesses in the children. We performed the retrospective analysis of the medical histories of 291 children presenting with this condition who had been admitted for the treatment to the ENT Department of the Morozovskzya City Children's Clinical Hospital during the period from January till December 2015. The study has demonstrated the following most common shortcomings of the outpatient treatment of the patients suffering from chronic tonsillitis at the stage preceding formation of paratonsillar abscess: inadequate antibacterial therapy of acute chronic tonsillitis or its exacerbation and limited indications for tonsillectomy at the level of the outpatient treatment. The leading role in the etiology of tonsillogenic pharyngeal abscesses in the children is played by beta-hemolytic Streptococcus of group A. It is concluded that the medical history suggesting past paratonsillar abscess is the absolute indication for the subsequent tonsillectomy in the children of any age.

Adenotonsillectomy can decrease enuresis and sympathetic nervous activity in children with obstructive sleep apnea syndrome

BACKGROUND

The nocturnal intermittent hypoxia caused by obstructive sleep apnea syndrome (OSAS) can provoke the sympathetic nervous activity (SNA). Salivary alpha-amylase (sAA) is a sensitive, non-invasive biomarker for reflecting the SNA, and a useful marker for pediatric OSAS subjects. Adenotonsillar hypertrophy (ATH) is the most commonly identified risk factor in OSAS childhood, therefore, several studies showed that the adenotonsillectomy (T&A) may alleviate nocturnal enuresis (NE) in children with OSAS.

OBJECTIVE

The present study was to investigate the effect of T&A on NE, the change of sAA value in ATH and OSAS children, with/without NE, and with/without the operation.

STUDY DESIGN

37 children (Group A) were admitted for ATH and NE. The saliva samples were taken before and after polysomnography for the measure of sAA. After the T&A, the children were followed-up for 1 year. 35 OSAS children with NE but no T&A were as a NE watchful-waiting group (Group B), 32 subjects without OSAS or NE were as non-OSAS control (Group C), 42 cases who underwent T&A but did not have NE were admitted to evaluate the SNA (Group D). Follow-up included evaluations for NE, sAA and urinary catecholamine after the T&A or at the equivalent time points.

RESULTS

The observational results in the present study showed a significant rate of the disappearance of NE 1 month after the T&A and had an almost complete resolution 1 year later. OSAS may irritate oxidative stress and increase SNA in pediatric subjects, which reflected by increased levels of sAA and urinary catecholamine, while the T&A can decrease enuresis and the SNA in children with OSAS (Figure).

DISCUSSION

Little research has previously focused on the relationship between childhood OSAS and the SNA. No data are currently available regarding comparisons of sAA levels before and after the T&A in children with OSAS and enuresis. Our findings in this present study showed that there was a resolution or decrease in enuresis events and drops in sAA levels following T&A, which were consistent with earlier study. However, there was no significant difference in the urinary catecholamine levels was found between OSAS groups with or without NE. Furthermore, there was no correlation between the urinary catecholamine and polysomnography parameters.

CONCLUSIONS

T&A has a favorable therapeutic effect on NE and may decrease SNA in children with OSAS. sAA might be associated with instability of ANS by OSAS and have a consistent relationship with the apnea-hypopnea index. Our studying aims had been met.

Trends and changes in paediatric tonsil surgery in Sweden 1987-2013: a population-based cohort study

OBJECTIVES

The objective of this study was to longitudinally describe the history of tonsil surgery in Swedish children and adolescents regarding incidence, indications for surgery, surgical methods and the age and gender distributions.

SETTING

A retrospective longitudinal population-based cohort study based on register data from the Swedish National Patient Register (NPR) and population data from Statistics Sweden.

PARTICIPANTS

All Swedish children 1-<18 years registered in the NPR with a tonsil surgery procedure 1987-2013.

RESULTS

167 894 tonsil surgeries were registered in the NPR 1987-2013. An increase in the total incidence rate was observed, from 22/10 000 person years in 1987 to 47/10 000 in 2013. The most marked increase was noted in children 1-3 years of age, increasing from 17 to 73/10 000 person years over the period. The proportion children with obstructive/sleep disordered breathing (SDB) indications increased from 42.4% in 1987 to 73.6% in 2013. Partial tonsillectomy, tonsillotomy (TT), increased since 1996 and in 2013 55.1% of all tonsil procedures were TTs.

CONCLUSIONS

There have been considerable changes in clinical practice for tonsil surgery in Swedish children over the past few decades. Overall, a doubling in the total incidence rate was observed. This increase consisted mainly of an increase in surgical procedures due to obstructive/SDB indications, particularly among the youngest age group (1-3 years old). TT has gradually replaced tonsillectomy as the predominant method for tonsil surgery.

Group A beta-hemolytic streptococcal pharyngitis and carriage rate among Egyptian children: a case-control study

BACKGROUND

Improper prescription of antibiotics for treatment of acute pharyngitis predisposes to emergence of a carrier state and antibiotic-resistant strains of group A streptococci (GAS). We sought to identify the frequency and antimicrobial susceptibility patterns of group A streptococci among Egyptian children with acute pharyngitis compared with asymptomatic children.

DESIGN AND SETTING

Case-control study conducted from September 2013 to August 2014 at a pediatric outpatient clinic in Egypt.

PATIENTS AND METHODS

Throat swabs were collected from children with acute pharyngitis and from asymptomatic children. We evaluated the accuracy of McIsaac scores and the rapid antigen detection test (RADT) for diagnosis of GAS pharyngitis with throat culture as a reference test. Antimicrobial susceptibility testing of GAS isolates was done by the disc diffusion method.

RESULTS

Of 142 children with acute pharyngitis (cases) and 300 asymptomatic children (controls) (age range, 4-16 years), GAS pharyngitis was diagnosed in 60/142 children (42.2%); 48/300 (16%) were found to be carriers. All GAS isolates in the case group were sensitive to penicillin; however, an MIC90 (0.12 micro g/mL) for penicillin is high and an alarming sign. The resistance rate to macrolides was 70% with the cMLSB phenotype in 65.1%. The sensitivities and specificities were 78.3% and 73.2% for McIsaac score of >=4 and 81.1% and 93.9% for RADT, respectively. GAS isolates in the control group were 100% sensitive to penicillin, while 12.5% and 37.5% were resistant to macrolides and tetracycline, respectively.

CONCLUSION

An increased MIC90 for GAS isolates to penicillin is an alarming sign. A high frequency of resistance to macrolides was also observed.

Accumulation of CD5+CD19+ B lymphocytes expressing PD-1 and PD-1L in hypertrophied pharyngeal tonsils

Programmed death-1 (PD-1) is one of the most important inhibitory co-receptors expressed predominantly on activated T and B lymphocytes whose expression could be sustained by permanent antigenic stimulation accompanying chronic or recurrent tonsillitis. The expression of PD-1 and PD-1L was analyzed using flow cytometry on hypertrophied tonsils collected from 57 children. We observed high expression of PD-1 and PD-1L on certain lymphocytes subpopulations of hypertrophied tonsils; among T cells, the expression of PD-1 on protein level was higher on CD4⁺ cells (70.3 %) than on CD8⁺ cells (35 %). Interestingly, a limited expression of PD-1 was observed on CD19⁺ B lymphocytes (6.5 %), while CD5⁺CD19⁺ B cells overexpressed PD-1 (52.5 %). Moreover, the expression of PD-1L was also higher on CD5⁺CD19⁺ B cells (16.5 %) than on CD19⁺ B cells (3.5 %) and on CD4⁺ T cells (20 %) than on CD8⁺ T cells (10 %). PD-1 and PD-1L expressions correlated only on CD5⁺CD19⁺ cells. In conclusion, high expression of PD-1 and PD-1L on T and B cells could represent hallmark of immune system adaptation to chronic antigenic exposition in patients with tonsillitis.