Analysis of aerobic bacterial strains found in chronic rhinosinusitis using the polymerase chain reaction

Histologic and Immunologic Observations of Viral-Induced Rhinosinusitis in the Mouse

Viral upper respiratory infection is one of the most common diagnoses made in primary care offices. Although symptoms resolve within 1 week for many patients, a percentage develops rhinosinusitis, and many of these patients are treated with antibiotics. We have developed a model of viral rhinosinusitis using intranasal inoculation of reovirus into mice that were then killed on postinoculation days 2, 4, 7, 10, 14, or 21 and heads were embedded in paraffin for histological and immunohistochemical analyses. Reovirus-like immunoreactivity was noted in the septa and paranasal sinus mucosa in mice as early as day 2, with peak intensity seen on day 4, and scant staining seen on day 7. Complete absence of viral staining was seen by day 10, which corresponded with increased intracellular adhesion molecule 1 immunostaining in the nose. By day 10, a large mucosal influx of B cells was observed, with a moderate influx of macrophages and smaller influx of T cells. By day 14, there was a peak in the number of B cells with a corresponding, but less pronounced peak in T cells, while macrophages began to decline at this point. By day 21, the panel of immune markers returned to near normal levels. The results of this study suggest that the immune system continues to produce a response as long as 2 weeks after clearance of viral antigens. One proposed mechanism for this phenomenon is that local factors such as cytokines are released continually after infection, even in the absence of persistent viruses or bacteria.

Bacteriology of Chronic Maxillary Sinusitis and Normal Maxillary Sinuses: Using Culture and Multiplex Polymerase Chain Reaction

Background

Although many investigations have been performed on bacteriology of chronic sinusitis and normal sinuses, there still is much discussion. Also a new bacterial agent, Alloiococcus otitidis determined in the nasopharynx and middle ear specimens can be thought as a causative agent of sinusitis.

Methods

The bacteriology of chronic maxillary sinusitis and maxillary sinuses with normal radiogram and endoscopic findings were studied by culture methods for aerobic and anaerobic bacteria. Multiplex polymerase chain reaction (PCR) was used to investigate four bacteria in study and control groups. There were 27 specimens in the study group and 28 specimens in the control group.

Results

In the study group, the bacteria commonly isolated were Staphylococcus aureus (11.1%), α-hemolytic streptococci (11.1%), Streptococcus pneumoniae (11.1%), Haemophilus influenzae (7.4%), coagulase-negative staphylococci (7.4%), and anaerobes (33.3%). Coagulase-negative staphylococci (14.3%), α-hemolytic streptococci (10.7%), and anaerobes (35.7%) were isolated also in the control group. PCR was used to investigate S. pneumoniae, H. influenzae, Moraxella catarrhalis, and A. otitidis in the study and control groups. None of these bacteria was determined in the control group whereas detection rates of these bacteria in the study group were 11.1, 11.1, 3.7, and 7.4%, respectively. It should be considered that PCR yielded faint amplification band for A. otitidis.

Conclusion

Using multiplex PCR can help to increase detection rates of bacterial etiology. Healthy sinuses are not sterile. A. otitidis may be one of the pathogens causing sinusitis.

A comprehensive review of the nasal microbiome in chronic rhinosinusitis (CRS)

Chronic rhinosinusitis (CRS) has been known as a disease with strong infectious and inflammatory components for decades. The recent advancement in methods identifying microbes has helped implicate the airway microbiome in inflammatory respiratory diseases such as asthma and COPD. Such studies support a role of resident microbes in both health and disease of host tissue, especially in the case of inflammatory mucosal diseases. Identifying interactive events between microbes and elements of the immune system can help us to uncover the pathogenic mechanisms underlying CRS. Here we provide a review of the findings on the complex upper respiratory microbiome in CRS in comparison with healthy controls. Furthermore, we have reviewed the defects and alterations of the host immune system that interact with microbes and could be associated with dysbiosis in CRS.

Endoscopically-derived bacterial cultures in chronic rhinosinusitis: A systematic review

BACKGROUND

Culture-directed antibiotic therapy represents an important component in the management paradigm of chronic rhinosinusitis (CRS). The objective of this study was to systematically review the literature to assess culture yield of the most common aerobic and anaerobic pathogens.

METHODS

A total of 43 studies between 1975 and 2010 were included.

RESULTS

The composite data comprised 3528 patients with 6005 total culture specimens. The cultures were obtained in operating room in 33 (76.7%) and clinic in 10 (23.3%) of the studies, respectively. The most common site of culture was the maxillary sinus in 18 (41.9%) of the studies. The most common assay techniques reported were swab in 19 (44.2%) and aspirate in 12 (27.9%) studies. The most common gram positive aerobes reported were coagulase negative Staphylococcus and Staphylococcus aureus in 630 (34.7%) and 481 (26.5%) of the cultures, respectively. The most common gram negative aerobes included Haemophilus influenzae and Pseudomonas aeruginosa in 245 (27.0%) and 198 (21.6%) cultures, respectively. The most common anaerobes reported were Peptostreptococcus species in 156 (19.6%) and Bacteroides species in 153 (19.2%) cultures.

CONCLUSION

This study provides a composite snapshot of the literature accrued on the microbiology of CRS. It should serve to apprise clinicians on the most common aerobic and anaerobic organisms in CRS patients when employing culture-directed antimicrobial therapy.

Detection of fungi in the sinus mucosa using polymerase chain reaction

OBJECTIVE

To compare the presence of fungi in the sinus mucosa of patients with and without chronic rhinosinusitis.

STUDY DESIGN AND SETTING

Prospective observational study using polymerase chain reaction and conventional culture to detect fungi in the sinus mucosa. Middle meatus mucosal samples were collected from 31 patients with chronic rhinosinusitis and 14 control subjects.

RESULTS

Fungi were detected in 6.5% of subjects with chronic rhinosinusitis and in none of the control subjects using polymerase chain reaction. Fungi were detected in 29% of subjects with the combination of inhalant allergies, nasal polyposis, and asthma. Fungi were detected in none of the subjects without the combination of these three comorbidities (P = 0.03).

CONCLUSION

Polymerase chain reaction assay appears to be able to detect fungi in chronic rhinosinusitis.

SIGNIFICANCE

Fungi may not be implicated in the pathogenesis of most chronic rhinosinusitis.

EBM RATING

B-3b.

Polymerase Chain Reaction for the Rapid Detection of Cerebrospinal Fluid Shunt or Ventriculostomy Infections

OBJECTIVE:

Infection after cerebrospinal fluid (CSF) shunts or ventriculostomies is a common complication associated with significant morbidity and mortality. Polymerase chain reaction (PCR) is a powerful molecular technique that allows rapid and precise amplification of bacterial deoxyribonucleic acid (DNA) and has proven a powerful tool in the detection of a wide variety of clinically important infectious diseases. We analyzed specimens of CSF derived from ventriculoperitoneal shunts or external ventricular drains by using both conventional cultures and PCR and report herein our preliminary results.

METHODS:

We selected 86 CSF samples from adult patients who underwent either shunt tap or routine surveillance cultures of their ventriculostomy. These specimens were chosen from a larger group of 300 specimens that were routinely collected (many serially) in our clinical practice. They were chosen because clinical suspicion of infection was increased because of either patient signs and symptoms (fever, stiff neck, lethargy, worsening neurological examination) or preliminary laboratory analysis of CSF data (increased white blood cell count, increased protein level, decreased glucose). We considered this subgroup optimal to efficiently initiate our investigation of the correlation of PCR and culture results. CSF was increased by using standard culture techniques and by using PCR. Samples of CSF that were to undergo PCR had DNA extracted, purified, and amplified for 16S rRNA using primers 16S-Forward and 16S-Reverse of conserved sequence regions of all bacteria. DNA was PCR-amplified for 30 cycles. One microliter of the first PCR product was subjected to nested PCR using primers specific for gram-positive and gram-negative bacteria. Samples were also subjected to PCR amplification for specific detection of Propionibacterium acnes, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus using specific primers for 16S rRNA Propionibacterium, nuclease gene of Staphylococcus, and Mec gene of methicillin-resistant Staphylococcus aureus.

RESULTS:

For 18 of 86 specimens (21%), both the culture and PCR were positive. For 30 of 86 specimens (35%), both the PCR and culture results were negative. For 42 of 86 specimens (49%), cultures were negative and PCR was positive. There were no positive culture results with negative PCR results. Most negative culture/positive PCR cases occurred after prolonged intravenous antibiotics. Of the 56 PCR-positive specimens, 30 were positive for Propionibacterium acnes, whereas 40 were positive for Staphylococcus aureus. Of the Staphylococcus aureus-positive specimens, two were positive for methicillin resistant-Staphylococcus aureus. Among the 56 PCR-positive specimens, 30 were positive for both Propionibacterium acnes and Staphylococcus aureus; gram-negative organisms were not detected by any method in these specimens.

CONCLUSION:

These preliminary data suggest that PCR is a highly sensitive, rapid, and potentially promising modality for the detection and treatment of CSF shunt ventriculostomy infection.

The role of atypical bacteria in chronic rhinosinusitis

OBJECTIVE

This study examines the presence of atypical bacteria in chronic rhinosinusitis (CRS) by utilizing the polymerase chain reaction (PCR).

STUDY DESIGN AND SETTING

Eleven patients with CRS were prospectively enrolled. DNA was isolated from the mucosa samples and subjected to PCR using oligonucleotides specific for identification of atypical bacteria including: Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella pneumophila. Also, routine aerobic and anerobic cultures were processed. Sinus tissue samples from 6 fresh corpses without evident sinus disease served as controls.

RESULTS

No atypical bacteria were identified in the 11 patient samples by PCR. One of 6 cadaver controls was positive by PCR for M pneumoniae. The most common organism obtained from routine culture was coagulase negative staphylococci.

CONCLUSION

Using sensitive PCR techniques, CRS mucosa did not reveal DNA from M pneumoniae, C pneumoniae, or L pneumophila.

SIGNIFICANCE

Atypical bacteria were not identified in patients with CRS despite highly effective PCR methods and they may not play a significant role in the cause of CRS.

Molecular analysis of bacterial flora associated with chronically inflamed maxillary sinuses

Chronic maxillary sinusitis is a chronic inflammatory condition in which the role of microbial infection remains undefined. Bacteria have been isolated from chronically inflamed sinuses; however, their role in the chronicity of inflammation is unknown. The objective of this study was to determine whether bacteria are present in clinical samples from chronic maxillary sinusitis and to assess the diversity of the flora present. Washes and/or tissue samples from endoscopic sinus surgery on 11 patients with chronic maxillary sinusitis were subjected to PCR amplification of bacterial 16S rDNA using three universal primer pairs, followed by cloning and sequencing. The samples were also assessed for the presence of bacteria and fungi by conventional culture methods. Viable bacteria and/or bacterial 16S rDNA were detected from maxillary sinus samples of five of the 11 patients examined (45 %). Three sinus samples were positive by both PCR and culture methods, one was positive only by PCR, and one only by culture. Thirteen bacterial species were identified: Abiotrophia defectiva, Enterococcus avium, Eubacterium sp., Granulicatella elegans, Neisseria sp., Prevotella sp., Pseudomonas aeruginosa, Serratia marcescens, Staphylococcus aureus, Stenotrophomonas maltophilia, Streptococcus gordonii, Streptococcus mitis/Streptococcus oralis and Streptococcus sp. Fungi were not detected. In one patient Streptococcus mitis/Streptococcus oralis, and in another patient Pseudomonas aeruginosa, were detected from both the sinus and the oral cavity using species-specific PCR primers. These results suggest that both aerobic and anaerobic bacteria can be detected in nearly half of chronic maxillary sinusitis cases.

Role of anaerobes in chronic sinusitis: Will polymerase chain reaction solve the debate

BACKGROUND

Bacteriology of chronic sinusitis continues to be a matter of debate, particularly the role of anaerobes. Some authors suggest that anaerobes play a significant role whereas others suggest a minimal role. Those who suggest a significant role argue that standard culture techniques are the culprits.

OBJECTIVE

The purpose of this study was to use polymerase chain reaction (PCR) on sinus specimens for the presence of anaerobes and to compare them with standard culture techniques.

METHODS

Sixty-four samples were obtained in a sterile fashion during sinus surgery and were sent for standard anaerobic cultures as well as anaerobic PCR analysis.

RESULTS

Anaerobic bacteria were demonstrated in 5% of culture specimens, which is similar to recently published data. PCR identified anaerobic bacteria in 19% of the specimens (P = 0.01).

CONCLUSION

PCR analysis of surgical samples obtained during endoscopic sinus surgery for chronic sinusitis identified a significantly higher incidence of anaerobes (x4) compared with standard anaerobic culture technique.

The role of infection in chronic rhinosinusitis

Chronic rhinosinusitis is a common condition, yet little is understood about its pathogenesis. Chronic infection traditionally has been considered a significant factor in the etiology and manifestations of chronic rhinosinusitis. Bacteria can be recovered in most cases of chronic rhinosinusitis, most commonly consisting of Staphylococcus species, anaerobes, and in some cases, gram-negative bacteria. Increasing trends toward bacterial resistance have been identified in chronic rhinosinusitis. Recently, a potential role for fungal infection has emerged. A knowledge of the microbiology of chronic rhinosinusitis will help guide treatment, but more research is required to understand further the exact role of infection in the pathophysiology of chronic rhinosinusitis.