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PubMed1997

Influence of age, gender and smoking on Streptococcus pneumoniae, Haemophilus influenzae and Moraxella (Branhamella) catarrhalis antibody titres in an elderly population.

The purpose of this study was to investigate the association of serum antibody levels to Streptococcus pneumoniae, Haemophilus influenzae and Moraxella (Branhamella) catarrhalis with age, gender and smoking in an elderly population. The study population comprised all the inhabitants aged 65 years or over in a rural municipality in south-western Finland. Serum samples were obtained from 1,174 out of a total of 1,360 subjects. Bacterial antibodies were measured by enzyme immunoassay (EIA) using pneumolysin and whole bacterial cells of H. influenzae and M. catarrhalis (mixture of 10 different strains for both) as antigens. The main findings were as follows: (i) antibody levels generally decreased with increasing age both in men and in women; (ii) antibody titres against H. influenzae and M. catarrhalis were higher in men than in women; and (iii) antibody titres to H. influenzae and M. catarrhalis, but not to S. pneumoniae, were significantly higher in smokers than in non-smokers. These data suggest that antibody-mediated protection against respiratory pathogens may be impaired in the elderly, leading to a higher susceptibility to respiratory tract infections, that the exposure to H. influenzae and M. catarrhalis may be higher in men than in women, and that smokers have more respiratory infections or colonization due to these 2 bacteria than do non-smokers.

Age Factors↗
PubMed1984

In vitro adherence of Moraxella bovis to intact corneal epithelium.

An in vitro assay is described using radiolabeled Moraxella bovis for studying adherence to intact bovine corneal epithelial surfaces. The assay was optimized for time (45 min) and for the ratio of epithelial cells to bacteria (1:1000) that demonstrated a significant difference in adherence between M. bovis strain 118F, a piliated organism and a nonpiliated variant, strain 118F/4-2. Adherence of these organisms correlated with previous pathogenicity studies involving experimental infection of calves. Scanning electron microscopy of tissues treated in the assay revealed a predilection of M. bovis for dark epithelial cells and for association with depressions in the tissue surface. This assay technique is discussed in comparison with other in vitro adherence assay methods.

Animals↗
PubMed2001

Isolation and characterization of a novel IgD-binding protein from Moraxella catarrhalis.

A novel surface protein of the bacterial species Moraxella catarrhalis that displays a high affinity for IgD (MID) was solubilized in Empigen and isolated by ion exchange chromatography and gel filtration. The apparent molecular mass of monomeric MID was estimated to approximately 200 kDa by SDS-PAGE. The mid gene was cloned and expressed in Escherichia coli. The complete mid nucleotide gene sequence was determined, and the deduced amino acid sequence consists of 2123 residues. The sequence of MID has no similarity to other Ig-binding proteins and differs from all previously described outer membrane proteins of M. catarrhalis. MID was found to exhibit unique Ig-binding properties. Thus, in ELISA, dot blots, and Western blots, MID bound two purified IgD myeloma proteins, four IgD myeloma sera, and finally one IgD standard serum. No binding of MID was detected to IgG, IgM, IgA, or IgE myeloma proteins. MID also bound to the surface-expressed B cell receptor IgD, but not to other membrane molecules on human PBLs. This novel Ig-binding reagent promises to be of theoretical and practical interest in immunological research.

Adhesins, Bacterial↗
PubMed2000

Association of Moraxella ovis with keratoconjunctivitis in mule deer and moose in Wyoming.

Six cases of infectious keratoconjunctivitis (IKC) in mule deer (Odocoileus hemionus) and moose (Alces alces) in Wyoming (USA) were investigated during fall and winter of 1995 and 1996. Excessive lacrimation, mucopurulent conjunctivitis, keratitis, and corneal opacity were observed in mule deer. Moose had severe mucopurulent conjunctivitis, keratitis, and corneal ulceration. Hemolytic, non-piliated Moraxella ovis was isolated from two mule deer and two moose. We attempted to reproduce IKC in three mule deer fawns using an isolate of M. ovis from a clinically affected mule deer. These fawns did not develop clinical signs of infection and the bacterium was not reisolated from inoculated deer. Inoculated deer may not have developed clinical signs because deer were not exposed to ultraviolet light or mechanical insult before inoculation. In addition, the isolate used for inoculation may have lost virulence factors through passage, or M. ovis may not have been the primary pathogen responsible for clinical disease in the natural cases of IKC we investigated. The etiology of IKC in free-ranging wild ruminants remains poorly understood.

Animals↗
PubMed1976

The structlre of pili (fimbriae) of Moraxella bovis.

Cells from rough and smooth colonies of Moraxella bovis were examined by electron microscopy utilizing both shadowing and thin sectioning techniques. Pili were found on the surfaces of cells from rough but not smooth colonies. Pili had a peritrichoud distribution and appeared as delicate (6.5-8.5 nm in diameter), elongated unbranched filaments. When bacteria were sectioned pili did not contain central pores and appeared to originate from opacities on the surface of the cell wall.

Animals↗
PubMed1976

Experimental production of infectious bovine keratoconjunctivitis: comparison of serological and immunological responses using pili fractions of Moraxella bovis.

The effect of vaccinating cattle and mice on the development of keratoconjunctivitis was studied. Cattle were vaccinated with whole cells, disrupted cells and pili fractions of three strains of Moraxella bovis. Mice were vaccinated with pili fractions of three strains. The resistance of all vaccinated animals was challenged with virulent cultures of M. bovis. In an attempt to correlate the response seen after vaccination and challenge with a pili fraction of M. bovis, vaccinated cattle and mice were grouped on the basis of signs of disease manifested and compared on the basis of serological responses. Serum samples were tested for antibodies by a gel diffusion precipitin test. A greater number of the sera of resistant cattle had antibodies to the homologous pili antigen than those of vaccinated nonresistant cattle. Cattle vaccinated with disrupted cells were not resistant to infectious bovine kerato-conjuctivitis and their sera lacked antibodies against the pili antigens. Vaccinated mice were more resistant to infectious bovine kerato-conjuctivitis and their sera lacked antibodies against the pili antigens. Vaccinated mice were more resistant to challenge exposure by homologous than heterologous cultures. A greater number of the sera of resistant mice had antibodies to pili antigens than nonresistant mice.

Animals↗
PubMed1999

Moraxella catarrhalis endocarditis: report of a case and literature review.

A 53-year-old man developed severe acute systemic illness three weeks after an upper respiratory tract infection. Serial blood cultures grew Moraxella catarrhalis. During antibiotic treatment, fever and infectious parameters disappeared, but severe aortic regurgitation developed. Aortic valve replacement was performed, during which extensive destruction of the aortic valve was noted. Endocarditis due to M. catarrhalis is very rare with, to our knowledge, only six cases having been reported to date. M. catarrhalis is a normal commensal of the upper respiratory tract, but in unpredictable circumstances can become an important pathogen. Bacteremia due to this organism therefore requires prompt treatment, as serious organ complications, including endocarditis, can occur.

Aortic Valve Insufficiency↗
PubMed1999

Comparative in vitro evaluation of dirithromycin tested against recent clinical isolates of Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae, including effects of medium supplements and test conditions on MIC results.

The use of macrolides for treatment of respiratory complaints has been complicated by susceptibility test conditions that adversely effect the in vitro test results and perceived potencies of these compounds. Dirithromycin was studied as to its in vitro activity compared to other macrolides as well as the effects that environmental incubation variations and inoculum concentrations may have on susceptibility results. Dirithromycin was less active than other macrolides tested (azithromycin clarithromycin, erythromycin) against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis with MIC90 values of 16, 32, and 1 microgram/ml, respectively; an activity that was most similar to roxithromycin. This reduced activity may be compensated by the superior pharmacokinetic properties that dirithromycin possesses compared to other members in its class. Method variation studies show that incubation in CO2 environments increase the MIC values for all macrolide compounds and dirithromycin was most effected by pH changes in three in vitro methods tested (Etest [AB BIODISK, Solna, Sweden] broth microdilution, and disk diffusion). Variations in inoculum concentration had minimal effect on dirithromycin potency. In addition the variability (lack of reproducibility) of the test results with dirithromycin were not significant. Dirithromycin is an alternative therapeutic choice among macrolide compounds for treatment of community-acquired respiratory infections caused by various streptococci, Legionella pneumophilia, Mycoplasma pneumoniae and M. catarrhalis, and also possesses a modest in vitro potency versus H. influenzae coupled with excellent pharmacokinetic properties. In vitro tests with dirithromycin will continue to be problematic for H. influenzae because of the adverse effects of recommended CO2 incubation for some standardized methods or commercial products (Etest).

Anti-Bacterial Agents↗
PubMed1999

Determination of the antimicrobial susceptibilities of Canadian isolates of Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis. Canadian Antimicrobial Study Group.

The susceptibility of Canadian isolates of three respiratory tract pathogens (Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae) to several antimicrobial agents were tested by two different methods. Beta-lactamase was produced by 68/211 (32.2%) of H. influenzae isolates and 64/75 (85.3%) of M. catarrhalis isolates. For S. pneumoniae, 19/156 (12.2%) isolates were resistant to penicillin (MIC > or = 0.12 mg/L) and two isolates had MICs of 1.5 mg/L. For some combinations of agents and organisms, different methods gave different values for the proportion of isolates susceptible. Regardless of methodology, for H. influenzae, the most active antimicrobials based on proportion of strains susceptible were ciprofloxacin (100%) and cefpodoxime (98.5-100%). For M. catarrhalis, the most active agents were azithromycin, cefaclor, cefixime, cefpodoxime, cefuroxime, ciprofloxacin, clarithromycin and loracarbef (100% each); the least active was ampicillin. Against penicillin-sensitive and -resistant pneumococci, the activity was not significantly different for azithromycin and clarithromycin (93.4-100%) and ciprofloxacin (MIC90 2.0 and 1.5 mg/L, respectively) but was different for cefuroxime (99.3% and 31.6%, respectively), cefaclor (MIC90 0.75 and > or = 256 mg/L, respectively), cefpodoxime (MIC90 0.047 and 1.5 mg/L, respectively) and loracarbef (MIC90 0.75 and > or = 256 mg/L, respectively). This study indicates the increasing incidence, in Canada, of beta-lactamase resistance in H. influenzae and M. catarrhalis and penicillin resistance in S. pneumoniae.

Anti-Bacterial Agents↗
PubMed1999

In vitro activities of macrolides against gram-positive aerobes, Haemophilus influenzae, Moraxella catarrhalis and Bacteroides fragilis in Taiwan.

BACKGROUND: New macrolides with improved pharmacokinetic characteristics have been developed and introduced for clinical use in Taiwan. In order to understand the antibacterial activities of these new macrolides, we tested their in vitro activities against common pathogenic bacteria. METHODS: Minimum inhibitory concentrations (MICs) of azithromycin, clarithromycin, dirithromycin, erythromycin and roxithromycin for clinical isolates collected from six teaching hospitals in Taiwan were determined by the agar dilution method. The tested bacteria included methicillin-sensitive and -resistant coagulase-negative staphylococci, methicillin-sensitive and -resistant Staphylococcus aureus, viridans streptococci, Streptococcus pneumoniae, Streptococcus pyogenes, Enterococcus spp, Corynebacterium spp, Haemophilus influenzae, Moraxella catarrhalis and Bacteroides fragilis. RESULTS: High MICs were detected against most of the bacteria tested except for H influenzae and M catarrhalis. The MIC90 for viridans streptococci, S pneumoniae, S pyogenes, Enterococcus spp, S aureus (both methicillin-sensitive and -resistant), coagulase-negative staphylococci (both methicillin-sensitive and -resistant), Coryne-bacterium spp, and B fragilis were all at least 128 micrograms/ml. Wide ranges of MICs were demonstrated. CONCLUSIONS: Most bacteria tested were highly resistant to macrolides. This result is a warning for clinicians that rational use of antibiotics, including macrolides, is mandatory.

Anti-Bacterial Agents↗
PubMed1999

Moraxella catarrhalis-induced purulent otitis media in the rat middle ear. Structure, protection, and serum antibodies.

To study the effects of viable and heat-killed Moraxella catarrhalis bacteria on the middle ear mucosa and to evaluate the protection after whole-cell immunizations, Sprague-Dawley rats were challenged and rechallenged with four different M. catarrhalis strains. The animals were monitored by clinical observations, bacterial and histological samples from middle ears, and serum IgG levels. Only viable bacteria at a high concentration induced purulent otitis media, which was culture positive in 58% of the cases on day 4. The infection was characterized by a mild acute reaction lasting otomicroscopically about 8 days, together with quantitative and qualitative changes of the goblet cells. Structurally the mucosal effects of the heat-killed bacteria were less pronounced in the early phase compared to the viable bacteria, but similar at the end of the experiment at 6 months. The intrabullar and subcutaneous immunizations evoked an IgG antibody response in all animals, and the protection rate after immunization was 50% or more. The induced protection was not strain-specific. The study showed the rat to be a possible alternative for the study of different aspects of M. catarrhalis otitis media, an infection that is clinically and structurally different from that elicited by Streptococcus pneumoniae and Haemophilus influenzae in the rat.

Animals↗
PubMed2000

Middle ear secretory capacity after acute otitis media caused by Streptococcus pneumoniae, Moraxella catarrhalis, non-typeable or type B Haemophilus influenzae. A comparative analysis based on goblet cell density.

To investigate whether the type of bacteria is correlated with an increase in goblet cell density during and after acute otitis media, we inoculated the middle ear of 25 rats with either Streptococcus pneumoniae, Moraxella catarrhalis, non-typeable or type b Haemophilus influenzae. Mucosal goblet cell density was determined by a whole-mount method on days 4, 8, 16, 60 and 180 post-inoculation. The goblet cell density was increased on all days of sacrifice, employing either bacteria, except M. catarrhalis 6 months after the acute incident. Type b H. influenzae induced the highest increase, followed by non-typeable H. influenzae, S. pneumoniae and M. catarrhalis. The mucosal area containing goblet cells was enlarged on all examination days, employing either bacteria. We conclude, that mucosal secretory capacity is highly increased during and up to 6 months after acute middle ear infection caused by either bacteria, conceivably predisposing a subsequent development of secretory otitis media. The results indicate that type b H. influenzae seems to be the bacteria most likely to induce a subsequent secretory condition.

Acute Disease↗
PubMed2000

Bacteremia and possible endocarditis caused by Moraxella phenylpyruvica.

Moraxella phenylpyruvica, a gram-negative coccobacillus, is usually considered a nonpathogenic bacterium. Only a few cases of invasive disease caused by this organism were reported in the 1970s. We report a well-documented case of bacteremia and possible endocarditis due to M phenylpyruvica in a previously healthy man.

Adult↗
PubMed1975

Bovine infectious keratoconjunctivitis: carrier state of Moraxella bovis and the development of preventive measures against disease.

Bovine infectious keratoconjunctivitis, which is caused by Moraxella bovis, occurs perennially in all cattle-raising areas. Disease may occur any time during the year but manifests itself often during summer when disease-enhancing factors such as ultraviolet radiation and fly population are increased. Although some recent research findings indicate that cattle can be immunized against the disease, many problems have to be overcome before the cattle industry can benefit from such immunization. Some pressing problems relate to lack of cross-protection between vaccines of different strains of M bovis, resistant or resilient carrier states, and how these factors affect vaccination regimens undertaken. Though cattle vaccinated with 1 strain are somewhat protected against subsequent challange by the same strain, protection against heterologous strains has not been demonstrated. In most herds, cattle harbor M bovis, and these carriers may serve as a source of infection.

Animals↗
PubMedDate not supplied

Antibiotic-sensitivity of Moraxella catarrhalis isolated from clinical materials in 1997-1998.

Moraxella catarrhalis (M. catarrhalis) may normally be found in the upper respiratory tract. This bacterium, however, may cause infections such as acute otitis media, sinusitis, conjunctivitis, bronchitis chronica, pneumonia, endocarditis, septicaemia and meningitis. Haemophilus influenzae, Streptococcus pneumoniae and M. catarrhalis were the main causative agents responsible for respiratory tract infections. The major resistance problems associated with these species are those which cause resistance to beta-lactams. beta-lactamase was produced by > 80% M. catarrhalis strains. The susceptibility to ampicillin, amoxicillin/clavulanic acid, cefuroxime, erythromycin, ciprofloxacin was tested in 137 M. catarrhalis strains. All the strains resistant to ampicillin produced beta-lactamase and were sensitive to amoxicillin/clavulanic acid. For M. catarrhalis, the most active antimicrobials included cefuroxime (99%), ciprofloxacin (99%) and erythromycin (93%).

Adult↗
PubMedDate not supplied

[Prevalence of Moraxella catarrhalis colonization in asymptomatic carriers under 6 years of age].

OBJECTIVE: To determine the prevalence of upper respiratory tract colonization by Moraxella catarrhalis in children under six years of age. MATERIAL AND METHODS: A survey was conducted between January and December 1998 in Mexico City, among children aged 2 months to 5 years, selected through cluster sampling. Pharyngeal samples were taken for M. catarrhalis identification. The minimal inhibitory concentration to different antibiotics was obtained and beta-lactamases were determined by the iodometric test. Statistical analysis consisted of frequency distributions, odds ratios, 95% confidence intervals, and Mantel-Haenszel chi 2. Statistical significance was set at p < 0.05. RESULTS: After excluding 37 children, the study population was 604 children from Mexico City; M. catarrhalis was present in 130 pharyngeal specimens (22.9%). Most of the strains were positive for beta-lactamase production (75.4%). Eighty percent of the strains was resistant to penicillin and 70% to ampicillin and amoxicillin. None were resistant to cefotaxime, imipenem, meropenem and erythromycin. CONCLUSIONS: Prevalence of M. catarrhalis upper respiratory tract colonization is similar to that of other respiratory pathogens. These findings warrant future research on the role of M. catarrhalis as an etiologic agent in acute and chronic respiratory infections in Mexico.

Age Distribution↗
PubMed2000

Isolation of Moraxella catarrhalis in patients at King Khalid University Hospital, Riyadh.

OBJECTIVE: A retrospective study was carried out to assess the clinical significance of Moraxella catarrhalis (M. catarrhalis) isolated from 32 specimens received from patients seen during a 2 year period. METHODS: The identity of isolates was confirmed by DNAse production and reduction of nitrate to nitrite. Susceptibility testing and B-lactamase production was carried out for each isolate. RESULTS: Twenty three of the patients were adults and 9 were children. Twelve (37%) of the isolates were from the sputum of patients aged more than 50 years with a clinical diagnosis of pneumonia, bronchitis or bronchiactesis. Six (18%) had M. catarrhalis isolated from sputum and had underlying cardiac, liver diseases or diabetes mellitus. The organism was isolated from the blood of one patient with pneumonia and one with leukaemia. It was also isolated from patients with sinusitis, conjunctivitis or otitis media. Twenty seven (84%) of the 32 strains produced B-lactamase, resistance to erythromycin and clindamycin was detected in 13% of the isolates. All isolates were susceptible to ciprofloxacin, tetracycline, trimethoprim-sulfamethoxazle, gentamicin, chloramphenicol, polymyxin B and neomycin. CONCLUSION: This study showed that M. catarrhalis can be an important respiratory tract pathogen in adults and children, able to invade the blood stream of patients with predisposing respiratory conditions and underlying systemic illnesses, as well as immunocompetent patients. Since most strains produce B-lactamase, antibiotic therapy should be guided by in-vitro susceptibility tests.

Adolescent↗