Fimbriae of Branhamella catarrhalis as possible mediators of adherence to pharyngeal epithelial cells

This study attempted to elucidate the role of fimbriae in the adherence of B. catarrhalis to human oropharyngeal epithelial cells. Antifimbrial immune serum was prepared by immunization of rabbit with whole fimbriated bacteria, and adsorption of the serum with a nonfimbriated B. catarrhalis strain. After pretreatment with the antifimbrial antiserum, the adherence of fimbriated B. catarrhalis to human epithelial cells was significantly decreased (p < 0.05). The adherence was also significantly (p < 0.001) decreased by trypsin treatment. Electron microscopy revealed destruction of fimbriae after trypsin treatment. These observations suggest that fimbriae are involved in the adherence of B. catarrhalis to epithelial cells.

[Clinical study of respiratory infection due to Branhamella catarrhalis using transtracheal aspiration]

We clinically investigated 40 cases of respiratory infection due to B. catarrhalis by transtracheal aspiration (TTA). The cases consisted of acute bronchitis (13 cases), pneumonia (14 cases), and chronic lower respiratory tract infection (13 cases). The infection was monomicrobial in 17 cases and polymicrobial in 23 cases with respect to the organisms isolated from TTA. The principal organisms isolated in combination with B. catarrhalis in cases of polymicrobial infection were S. pneumoniae and H. influenzae. All of the 6 cases of death were patients with pneumonia who had malnutrition and immunological hypofunction. These results suggest that B. catarrhalis is an important pathogen in respiratory infection.

[Perspective: new pathogens: Branhamella catarrhalis, Capnocytophaga turleri, Corynebacterium group JK]

Branhamella catarrhalis is an important pathogen of upper and lower respiratory tract. According to findings in literature, it mostly causes bronchopulmonary infections. Capnocytophaga is a newly recognized genus of the gram negative bacilli. In various reports, it has been recognized that capnocytophaga mostly causes sepsis. Bacteria of Corynebacterium group JK (CJK) cause many important local infections and sepsis.

The role of Branhamella catarrhalis in the "bloody-nose syndrome" of cynomolgus macaques

During a 15-month period, 25 cynomolgus macaques (Macaca fascicularis) at the Johns Hopkins University were observed to have nasal discharge. Fifteen (60%) of these animals had positive nasal cultures for Branhamella catarrhalis. Clinical signs associated with infection by this bacterium were sneezing, epistaxis, and mucohemorrhagic nasal discharge. Treatment with antibiotics resulted in prompt resolution of clinical signs. Post-therapeutic nasal cultures were negative for B. catarrhalis. Two groups of clinically normal, culture-negative, cynomolgus macaques were inoculated with natural isolates of B. catarrhalis which had been passaged in culture for various amounts of time. Five of the eight animals inoculated became culture-positive and had mild nasal discharge. Presence of blood on nasal swabs was indicative of infection with B. catarrhalis. Three of the inoculated animals had post-swabbing epistaxis. This report documents the role of B. catarrhalis as an upper respiratory pathogen in the cynomolgus monkey which causes mild self-limiting disease reminiscent of the so-called "Bloody-Nose Syndrome." In addition to the obvious clinical significance of this finding to primate clinicians, development of an animal model for human disease caused by this organism may be possible.

[Branhamella catarrhalis as a disease pathogen]

Since 1980, numerous reports have been published throughout the world on the pathogenic role of Branhamella catarrhalis. Apparently, Branhamella infections have been increasing in many places. Although they can affect various organs, they are most commonly observed in the airways and eye (both in children and adults). Not infrequently, Branhamella catarrhalis causes sepsis, in particular in immunosuppressed patients. The rapid increase in beta-lactamase-forming Branhamella strains results in frequent ineffectiveness of treatment with penicillin. In patients treated with penicillin for a primary infection by other bacteria, a secondary infection due to penicillin-resistant Branhamella organisms can subsequently occur. For treatment, therefore, beta-lactamase-stable antibiotics should be preferred.

Branhamella (Moraxella) catarrhalis: pathogenic significance in respiratory infections

OBJECTIVES

To assess the pathogenic significance of Branhamella catarrhalis isolates in patients with respiratory infections and to define the clinical characteristics of such patients.

DESIGN AND SETTING

Respiratory specimens were assessed in a three-year prospective study performed in a Brisbane metropolitan hospital. Assessment of the pathogenic significance of isolates of B. catarrhalis was based on four predetermined criteria: (i) clinical evidence of respiratory infection based on history, examination and chest x-ray; (ii) isolation of B. catarrhalis as the sole potential pathogen; (iii) absence of antibiotic treatment in the previous two weeks; and (iv) subsequent clinical response to an antibiotic to which the isolate was sensitive.

RESULTS

B. catarrhalis was identified in 118 respiratory samples, 92 (78%) being from patients less than 10 years old. Infection with B. catarrhalis was more commonly seen in winter months and was community-acquired in two-thirds of cases. Isolation of this organism was associated with a broad variety of upper and lower respiratory tract syndromes. Isolates were considered to be of pathogenic significance (all four above criteria satisfied) in 35% of cases and of possible significance (the first and fourth criteria satisfied) in a further 15% of cases. Isolates were more likely to be of pathogenic significance in older patients and in those with pre-existing cardiorespiratory disease; however, a number of serious infections were observed in previously-well children. Expectorated sputum and tracheal aspirates were more likely to yield a clinically significant isolate than nasopharyngeal aspirates. Production of beta-lactamase was demonstrated in 88% of isolates.

CONCLUSION

B. catarrhalis causes respiratory infection more frequently than is generally appreciated. Isolation of this organism from the respiratory tract had pathogenic significance or possible pathogenic significance in 50% of our patients. If therapy is indicated in patients with respiratory infection caused by this organism, traditional beta-lactam regimens cannot be relied upon, as shown by the high rate of beta-lactamase production in this study; a tetracycline, erythromycin, a second or third generation cephalosporin, or the combination of a penicillin derivative and beta-lactamase inhibitor should be considered.

Possible presence of a capsule in Branhamella catarrhalis

Clinical isolates of Branhamella catarrhalis from patients with respiratory infections were used in this study. Electron microscopic observation after treating Branhamella catarrhalis with immune serum and ruthenium red revealed the capsule. In the phagocytosis test, most organisms were not ingested by human polymorphonuclear neutrophils in the presence of normal rabbit serum (NRS), while organisms were primarily cell associated and apparently ingested in the presence of immunized rabbit serum (IRS). The capsule may be one of the virulence factors in this bacteria. This study demonstrates the possible presence of a capsule in Branhamella catarrhalis.

Significance of Haemophilus spp. and Branhamella catarrhalis in upper respiratory tract infections

Haemophilus influenzae and Branhamella catarrhalis can be considered inhabitants of the upper respiratory tract in humans. Although the pathogenetic role of H. influenzae cannot be discussed, the Authors report the mechanisms of pathogenicity of this microorganism; furthermore, they discuss the direct or indirect pathogenicity of B. catarrhalis in respiratory tract diseases and the ability of both microorganisms to produce beta-lactamases. H. influenzae and B. catarrhalis, together with S. pneumoniae, are the most common bacteria responsible for upper respiratory tract infections, namely otitis and sinusitis. The activity of these bacteria in the onset of otitis and sinusitis is reported.

[Bronchopulmonary infection due to Branhamella catarrhalis in patients with obstructive lung disease]

During the period from February 1988 to April 1990, 214 sputum samples from COPD patients with bronchopulmonary infection were quantitatively cultured. 17 strains were identified as Branhamella catarrhalis, being present in 7.9% of all sputum cultures and 11.0% of those positive for a pathogen (Quantity = 10(10)/L of Isolated Organism). Half of B. catarrhalis infection was isolated in mixed with other pathogens. Haemophilus influenza was the most frequently associated pathogen. The second was H. influenza plus Streptococcus pneumoniae. Of 17 B. catarrhalis, 2 strains were positive for beta-lactamase. The incidence of B. catarrhalis infection varied with the seasons, being prevalent in late winter and early spring. Many factors contributed to the pathogenicity of B. catarrhalis, such as the rapid increase of positive beta-lactamase strains and the change of seasons. The result showed that B. catarrhalis was the fourth frequent pathogen in COPD patients accompanied with bronchopulmonary infection. Most of the strains were resistant to penicillin, and beta-lactamase strains were discovered. Therefore, B. catarrhalis should be as a potential pathogen to be identified in sputum. A suitable method was recommended to identified B. catarrhalis.

Respiratory tract carrier rates of Moraxella (Branhamella) catarrhalis in adults and children and interpretation of the isolation of M. catarrhalis from sputum

Nonselective media and previously described selective media were used to study the occurrence of Moraxella (Branhamella) catarrhalis in sputum samples of good and poor quality and in samples taken from different sites of the upper respiratory tracts of healthy subjects. It was found that in healthy adults the carrier rate was 5.4%, as opposed to 50.8% in children and 26.5% in people older than 60 years. M. catarrhalis was recovered significantly more often from sputum samples of good quality (5%) than from poor quality samples (0.5%), and when present, it was found mostly in the presence of high inocula. From these data gathered from healthy and diseased subjects, it is concluded that the presence of M. catarrhalis in the sputum of adults is rarely due to oronasopharyngeal contamination of the sputum. Similar findings reported by others are discussed, and the origins of the currently held concept that M. catarrhalis is a common commensal organism of the human upper respiratory tract are traced.

[Pathogenesis of bacterial respiratory infection and new approach of the treatment]

Causative agents of respiratory infections has been changed because of increase in number of aged people and compromised host and the rapid development of new chemotherapeutic agents. Especially Branhamella catarrhalis (B. catarrhalis), which is very unique and has become a common respiratory pathogen, since 1980, in my department. Attachment ability of B. catarrhalis to oropharyngeal cells coincided with the acute exacerbation of chronic respiratory infections by this bacterium and the same phenomenon in pneumococcal infections was also established. In the hospital for aged people, two major pathogens Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) are specially seen. In these patients, the two major ones were isolated from the oropharynx. Non-typable Haemophilus influenzae (H. influenzae) is also very important in Japan like USA. Recurrent infection with this pathogen occurred due to the change of OMPs during the time period of more than one month. Complement and some amount of ceftadizim were inactivated by destroyed neutrophils in vitro. This result may explain one of the cause of intractability of P. aeruginosa infection. Monoclonal antibody against P. aeruginosa showed effectiveness in P. aeruginosa pneumonia model in mice. Intraabdominal administration of fibronectin also was effective for staphylococcal pneumonia in rat. Oropharyngeal pathogens like S. aureus, S. pneumonia, B. catarrhalis, H. influenzae and P. aeruginosa were killed by 100-500 times diluted solution of 7% povidonjod solution. Moreover the frequency of recurrence of infection by these bacteria were decreased by gargling this solution 3-4 times/day.(ABSTRACT TRUNCATED AT 250 WORDS)

Branhamella catarrhalis: an organism gaining respect as a pathogen

Branhamella catarrhalis was formerly regarded as a common, essentially harmless inhabitant of the pharynx. This misapprehension was caused, in part, by confusion with another pharyngeal resident, Neisseria cinerea. The two organisms can now be differentiated by the positive reactions of B. catarrhalis in tests for nitrate reduction and hydrolysis of tributyrin and DNase. B. catarrhalis is currently recognized as the third most frequent cause of acute otitis media and acute sinusitis in young children. It often causes acute exacerbations of chronic bronchopulmonary disease in older or immunocompromised adults and is incriminated occasionally in meningitis, endocarditis, bacteremia, conjunctivitis, keratitis, and urogenital infections. Virulence-associated factors, such as pili, capsules, outer membrane vesicles, iron acquisition proteins, histamine-synthesizing ability, resistance to the bactericidal action of normal human serum, and binding to the C1q complement component, have been identified in some strains. beta-Lactamase producing strains, first detected in 1976, have risen to approximately 75% worldwide. Thus far, however, practically all American strains of B. catarrhalis remain susceptible to alternative antibiotics. A possible selective advantage of recent isolates is their reportedly heightened tendency for adherence to oropharyngeal cells from patients with chronic bronchopulmonary disease.

[Branhamella catarrhalis: its respiratory pathogenicity in childhood]

Branhamella catarrhalis is a nasopharyngeal commensal which is being increasingly recognised as a pathogen, causing mainly infective exacerbations of chronic lung disease. It can also originate serious infections, like septicaemia, in patients with chronic predisposing conditions. During the period from 1979 to 1987, 22,501 respiratory tract samples from children were evaluated. Ninety nine isolated of Branhamella catarrhalis were identified (0.44%). Patients' age extended from 12 days to 9 years, with patients younger than two years representing 73%. Sixty three out of 77 cases investigated (82%) were positive for beta-lactamase. The most frequent finding was the recovery of Branhamella catarrhalis in tracheal aspirates from children with a tracheotomy or prolonged nasotracheal intubation. One of these children had a septic episode during which Branhamella catarrhalis was isolated from blood. Also remarkable is a case of pneumonia in a patient with congenital hypogammaglobulinaemia. Branhamella catarrhalis was also recovered in a wide variety of acute upper and lower respiratory tract infections in children without previous predisposing conditions. It is less clear its pathogenic role in these cases.

Branhamella catarrhalis: phenotypic characteristics

PURPOSE

This review provides a comprehensive description and discussion of recognized phenotypic characteristics of Branhamella catarrhalis. An emphasis is placed on attributes of this organism that are relevant to its recovery and identification in the clinical microbiology laboratory. In addition, characteristics useful in determining strain identity for use in epidemiologic investigations are addressed. Finally, factors are discussed that may account for the infection-causing potential of B. catarrhalis or at least are of potential consequence to investigations of the pathogenesis of Branhamella disease.

CONCLUSIONS

B. catarrhalis is readily isolated from human clinical specimens and can be easily identified using simple, rapid laboratory techniques. Restriction endonuclease analysis of chromosomal deoxyribonucleic acid has proven to be a useful tool in epidemiologic studies. Beta-lactamase isoelectric focusing is of limited value because of the small number of distinct patterns. The lipopolysaccharide and outer membrane proteins of B. catarrhalis have been characterized and found to be relatively non-varying among different strains. Circumstantial evidence exists in support of the hypothesis that the B. catarrhalis beta-lactamase is a virulence determinant.

Spectrum of disease due to Branhamella catarrhalis in children with particular reference to acute otitis media

For many years Branhamella catarrhalis was regarded as a non-pathogenic inhabitant of the respiratory tract. This article outlines the spectrum of B. catarrhalis disease in childhood and the extent of the evidence for a pathogenic role of the organism. B. catarrhalis is a rare etiologic agent in septicemia, meningitis, and other systemic illness in both apparently normal and immunocompromised infants and children. It is an unusual cause of ophthalmia neonatorum, but can be confused with Neisseria gonorrhoeae. Whether or not B. catarrhalis is acquired from the birth canal in these cases has not been established. B. catarrhalis is most common as a respiratory tract pathogen in children, including pneumonia, bacterial tracheitis, sinusitis, and otitis media. Since it is difficult to rigorously document pathogenicity of any bacterium in bronchopulmonary infections in children, it is probable that the spectrum of B. catarrhalis disease is wider than that reported to date. The evidence for pathogenicity in acute otitis media is more extensive than for other infections. Otitis media due to B. catarrhalis is clinically similar to that due to other pathogens. B. catarrhalis can be isolated in pure culture from the middle ear exudate and persists if there is no antibacterial treatment. Gram-negative intracellular and extracellular diplococci can be seen on smears of the inflammatory exudate. There is preliminary evidence that there is an antibody response in B. catarrhalis otitis media. B. catarrhalis has emerged as an important and common pathogen in neonates, infants, and children.

Studies of the outer membrane proteins of Branhamella catarrhalis

PURPOSE

Branhamella catarrhalis has emerged as an important human pathogen in the past several years. Therefore, studies of the outer membrane have been undertaken in order to identify virulence factors and begin to understand the immune response to infection.

MATERIALS AND METHODS

The outer membrane of B. catarrhalis has been purified by sucrose density centrifugation. The outer membrane proteins (OMPs) of 50 strains from diverse sources were isolated by simpler methods and studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Experiments were designed to identify OMPs that express determinants on the surface of the intact bacterium.

RESULTS

Eight major OMPs have been identified (OMPs A through H). The OMP patterns from diverse strains were strikingly similar. OMP E (approximately 56,000 daltons) and OMP G (approximately 28,000 daltons) have determinants that are surface-exposed and these determinants are shared among a majority of strains of B. catarrhalis.

CONCLUSION

These observations have important implications with regard to the immune response to infection and future vaccine development.

[Infections caused by Branhamella catarrhalis]

Branhamella catarrhalis, formerly Neisseria catarrhalis, is a common bacteriological finding in the upper respiratory tract in infancy, and it ranks third on the list of bacterial causes of otitis media and sinusitis. In adults Branhamella catarrhalis may cause acute exacerbations of bronchitis and pneumonia, especially in patients with chronic lung disease. Branhamella catarrhalis is being recognized more frequently as a nosocomial pathogen and it may cause septicaemia in immunocompromised patients. Resistance to penicillin is prevalent and is due to production of beta-lactamases. The pathogenic potential of this agent should not be overlooked.

Fulminant Branhamella catarrhalis tracheitis

Branhamella catarrhalis, a well known commensal of the normal respiratory flora, is being increasingly implicated as an aetiological agent in various acute respiratory and non-respiratory infections. B. catarrhalis has demonstrated a particular predilection for turning pathogenic in the immunocompromised host. Bacterial tracheitis, presenting as an acute airway obstruction, is commonly caused by Staphylococcus aureus and Haemophilus influenzae. The unusual occurrence of a fulminant B. catarrhalis bacterial tracheitis in a previously normal and healthy Indian child is the subject of this communication.

The significance of Branhamella catarrhalis in bronchopulmonary infection--a case-control study

Data, including clinical features of bronchopulmonary infections, i.e. cough with purulent sputum, fever, peripheral blood leucocytosis, patchy pulmonary shadows on chest radiographs and the presence of crepitations or dullness on examination of the chest, were prospectively recorded in 107 consecutive adult patients whose expectorated sputum yielded Branhamella-like bacterial colonies in routine cultures. Subsequently, isolates from 26 patients were confirmed to be Branhamella catarrhalis. Of 81 patients (unmatched controls) with confirmed commensal Neisseria species, 40 (matched controls) were age and sex matched with the 26 patients (cases) positive for B. catarrhalis. Clinical features of bronchopulmonary infection were significantly more among cases compared to unmatched controls. Compared with matched controls, significantly more of the cases had three or more clinical features of bronchopulmonary infection (P less than 0.05). This is the first study of the clinical significance of B. catarrhalis in expectorated sputum that included controls to circumvent the confounding effects of oropharyngeal and airway colonisation in patients with bronchopulmonary infections. The isolation of this organism in routine sputum culture was found to be significantly related to clinical infection.

[Branhamella catarrhalis in respiratory infections]

Given the increasing interest that Branhamella catarrhalis is acquiring as a possible pathogen of the respiratory tract, we have studied 81 sputum samples of patients with respiratory problems with the aim of evaluating its clinical significance. In 22 of these patients (27.2%) the implication of B. catarrhalis could be established, either as a primary pathogen (40.9%) or in association with other pathogens, especially with Haemophilus influenzae (36.4%). Chronic bronchitis and bronchopneumonia were the clinical manifestations more frequently associated with B. catarrhalis. 79.0% of the strains were beta-lactamase producers, although only 58.0% of them were resistant to ampicillin.

Branhamella catarrhalis bronchopulmonary isolates in PICU patients

Branhamella catarrhalis is commonly considered a respiratory commensal but has recently been implicated as a pathogen, particularly in adults. Over a 28 month period, B. catarrhalis was isolated from bronchopulmonary secretions of 14 PICU patients with acute respiratory infections. Twelve patients had pneumonia and two had tracheitis. The mean age was 3.5 years. Seven patients had chronic cardiopulmonary disease including two who were immunosuppressed. Three had an acute underlying condition and four had no complicating medical problem. Polymorphs and Gram-negative diplococci on Gram stain were found in respiratory secretions of all patients. Twelve of 14 isolates produced beta-lactamase, and six patients had a second potentially pathogenic bronchopulmonary isolate. All patients were treated for B. catarrhalis infection and none died. When isolated in pure culture from bronchopulmonary secretions in symptomatic patients, B. catarrhalis should be considered a pathogen. When isolated in mixed culture, its pathogenic role is uncertain. We conclude that B. catarrhalis can be a bronchopulmonary pathogen in critically ill children with otherwise normal cardiopulmonary function as well as in those with chronic cardiopulmonary dysfunction. When administering antibiotics the high frequency of beta-lactamase-producing strains must be taken into consideration.

Effect of age on adherence of Branhamella catarrhalis to buccal epithelial cells

The role of adherence in the pathogenicity of Branhamella catarrhalis in lower respiratory tract infection in the elderly was investigated. Differential adherence of this organism to buccal epithelial cells of elderly inpatients, outpatients, and young controls was measured. The mean number of bacteria adherent per cell was 36.9 +/- 11.2, 40.2 +/- 6.1 and 16.5 +/- 12.8 for inpatient and outpatient elderly and young controls respectively (significantly different p less than 0.01, Student's t test). This significantly higher level of adherence in the elderly subjects suggests that increased adherence may contribute to the incidence of respiratory tract infection due to B. catarrhalis seen in this group.