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P Bol

Publications and source records attributed to P Bol.

At least 109 records · Page 6Linked to original sources
PubMed1990

Clones of serogroup B Neisseria meningitidis causing systemic disease in The Netherlands, 1958-1986.

Serogroup B isolates of Neisseria meningitidis recovered from 278 patients with systemic disease in the Netherlands between 1958 and 1986 were analyzed with respect to serotype and multilocus enzyme genotype. Of the isolates, 28% were serotype 2b and 53% were neither serotypeable nor serosubtypeable. There were 145 distinct multilocus genotypes (electrophoretic types, ETs), with up to 31 isolates belonging to the same ET. Temporal changes in the genotypic composition of meningococcal populations in the Netherlands were demonstrated by the recent occurrence of disease caused by three clone lineages, I, III, and VI, that were not found before 1975. The epidemic of 1966-1967 and the hyperendemic wave of 1972 were caused, in large part, by two closely related but distinct clones of serotype 2b isolates, ET-11 and ET-17, respectively. Deviations in male-to-female ratio and age distribution of patients were observed for disease caused by isolates of individual clone lineages.

Adolescent↗
PubMed1989

Clinical and epidemiologic aspects of members of Aeromonas DNA hybridization groups isolated from human feces.

Between June 1982 and May 1987 Aeromonas species were isolated from 208 of 34,311 (0.61%) fecal samples submitted to a Regional Public Health Laboratory in The Netherlands. Aeromonas isolates were found most frequently in summer and rarely in winter. Of 169 Aermonas isolates that were available for further study, 19% were isolated from patients with a mixed infection, 5% from patients with underlying diseases, and 15% from patients who used medication that could predispose the intestinal tract to colonization with Aeromonas species. Aeromonas species that produced cytotoxins to Vero cells (cytotoxigenic) were found in hybridization groups 1 (11% of all isolates), 2 (1%), 3 (2%), and 8 (25%) and were identified phenotypically as A. hydrophila or A. sobria. Aeromonas species that did not produce cytotoxins to Vero cells (noncytotoxigenic) were found in hybridization groups 4 (57%) and 5A (4%) and were identified phenotypically as A. caviae. Distribution of Aeromonas species by age showed a predominance of noncytotoxigenic strains in children under the age of 5 years (46% of all noncytotoxigenic strains), while cytotoxigenic strains were mainly cultured from patients aged 50 years or older (54% of all cytotoxigenic strains). Significant correlations were found between cytotoxigenic strains and hospitalization, foreign travel, and contact with surface water. Cytotoxigenic strains were isolated significantly more often than noncytotoxigenic strains from patients with diarrhea, but in a multivariate analysis including age, previous medication, underlying disease, and foreign travel, this association was not significant.

Aeromonas↗
PubMed1988

Comparison of antibiotic resistant and sensitive strains of Haemophilus influenzae type b in The Netherlands by outer-membrane protein subtyping.

The percentage of beta-lactamase producing Haemophilus influenzae strains from patients with meningitis in The Netherlands increased from 0% in 1975/1976 to 4.6% in 1985/1986 (n = 1559). Twenty-three isolates resistant to ampicillin, penicillin, chloramphenicol, rifampicin and/or tetracycline were subtyped to determine if one resistant strain was spreading. (Sub)typing was performed by capsular typing, analysis of the major outer membrane protein patterns on sodium dodecylsulfate gels (SDS-PAGE subtypes), lipopolysaccharide serotyping and biotyping. The (sub)types of the resistant strains were similar to those of sensitive strains, thus indicating that antibiotic resistant strains develop at random.

Anti-Bacterial Agents↗
PubMed1987

Haemophilus influenzae type b strains of outer membrane subtypes 1 and 1c cause different types of invasive disease.

Of 275 consecutive Haemophilus influenzae type b (Hib) strains isolated from children with invasive disease in Finland in 1985-86, 74% were of the common European outer membrane protein (OMP) subtype 1 and 22% were of OMP subtype 1c, which is usually rare. Strains of subtype 1c caused proportionately more meningitis and less epiglottis than did strains of subtype 1c. Furthermore, children with disease due to strains of subtype 1c were younger than those with disease due to strains of subtype 1. The significant difference in association between subtype and the diagnosis of epiglottitis or meningitis remained even when the strong influence of age was accounted for. This finding may suggest a true difference in the virulence between these subtypes not previously demonstrated for Haemophilus influenzae type b.

Age Factors↗
PubMed1987

Epidemiology of Haemophilus influenzae meningitis in patients more than 6 years of age.

Haemophilus meningitis was found to be rare in those more than 6 years of age in The Netherlands (incidence: 1/10(6)/year). Persons of this age account for only 6-7% of all cases. The histories of a representative sample of 35 of 73 patients over the age of 6 years with Haemophilus influenzae meningitis were reviewed and correlated with the characteristics of the causal strains. Altogether, these patients had suffered 51 episodes of purulent meningitis. Sequelae were found after five of the 35 H. influenzae episodes studied (14%) but none of the patients died during one of these episodes. Of all the patients, 54% had severe predisposing factors, mainly CSF leaks following road traffic accidents or operations, which often led to recurrent bouts of meningitis; these patients were predominantly males. In the patients aged 15-64 years, predisposing factors were present in 74%. Predisposed patients were infected mainly by unencapsulated strains and, as far as type b strains were involved, by uncommon subtypes. Unencapsulated strains were hardly ever able to invade the bloodstream, primarily or secondarily. Careful review of the patient's history is important in this rare disease, because, in many patients, the presence of a CSF fistula may become evident and surgery is likely to prevent recurrences.

Adolescent↗
PubMed1987

Types and subtypes of 73 strains of Haemophilus influenzae isolated from patients more than 6 years of age with meningitis in The Netherlands.

Strains of Haemophilus influenzae isolated in The Netherlands between 1975 and 1984 from patients with meningitis were analysed in order to determine whether older patients are infected with particular types or subtypes of the organism. Of 1154 patients with H. influenzae meningitis 73 (6.3%) were more than 6 years of age. Thirty-one strains (42%) were of serotype b, one strain was of serotyped, one strain was of serotype f and 40 strains (55%) were non-typable. Twenty-eight type b strains were available for subtyping by analysis of the major outer-membrane proteins by sodium dodecylsulphate (SDS)-polyacrylamide gel electrophoresis (PAGE), by serotyping of their lipopolysaccharides and by biotyping. Twenty-one strains were outer-membrane protein subtype 1,24-lipopolysaccharide serotype 1 and 24 biotype I. Seventeen strains (61%) combined these characteristics. This percentage did not differ significantly from the percentage found for strains isolated from patients of all age groups (80%). The 32 non-typable H. influenzae strains analysed had different outer-membrane protein patterns as seen by SDS-PAGE. Five biotypes were found, among which biotype II was predominant (21/32). The results indicated that (i) patients more than 6 years of age were infected by subtypes of H. influenzae b strains which were not significantly different from the strains isolated from younger patients, (ii) non-typable strains of H. influenzae were much more common (55%) in the older age group than in the younger (1.2%) and (iii) that these non-typable strains were not of a particular subtype.

Adolescent↗
PubMed1987

Association of meningococcal serotypes with the course of disease: serotypes 2a and 2b in the Netherlands, 1959-1981.

Case histories of 692 patients with meningococcal disease due to serogroup B, C, or W (W-135) were reviewed to study the association of the serotypes 2a and 2b with the course of disease. The case-fatality rate in group B disease was significantly associated with serotype 2b (B:2b) strains (P = 0.03). Age and year of admission did not account for this association. Septicemia was also found more frequently with B:2b than with other B serotypes, but neurological complications and sequelae were not. Neither C:2a nor W:2a was associated with a higher case-fatality rate, with more cases of septicemia, or with more sequelae than were other C or W serotypes. We concluded that the 2b antigen, although not likely a causal factor, is a virulence marker among group B strains and that the protective effect of a vaccine containing this protein (among others) needs to be studied.

Antigens, Bacterial↗
PubMed1987

Association of meningococcal serogroups with the course of disease in the Netherlands, 1959-83.

To study the association of meningococcal serogroups with the course of disease, we reviewed the case histories of 1221 patients. The meningococci from these patients constituted a sample from isolates collected and serogrouped systematically in the Netherlands since 1959. Of these 1221 isolates, 64% were serogroup B. The overall case fatality rate was 5.1%, and the rate was lowest for patients with serogroup A infections (2.3%) and highest for serogroup W135 (18%) (P < 0.01). The occurrence of septicaemia without meningitis (case fatality rate 15.3%) was similarly distributed among the serogroups (A, 4.0%; W135, 30%). Sequelae occurred in 7.9% of patients (loss of hearing, 3.2%) and were remarkably prevalent after disease due to minor serogroups (X and Y: 4 out of 12). In a log-linear analysis, both age and serogroup were significantly associated with case fatality rate and with the occurrence of septicaemia and sequelae. It is argued that these data are representative, despite the problems inherent in a retrospective investigation. The course and outcome of meningococcal disease appear to be related to the Neisseria meningitidis serogroup and to host factors.

Adolescent↗
PubMed1986

Meningococcal disease in The Netherlands, 1959-1981: the occurrence of serogroups and serotypes 2a and 2b of Neisseria meningitidis.

By means of a filter radioimmunoassay and the use of monoclonal anti-2a and anti-2b antibodies, we have serotyped 3164 of 3688 strains of Neisseria meningitidis isolated from patients in The Netherlands between 1959 and 1981. Serotypes 2a and 2b were distributed differently among the major serogroups A, B, C, and W-135. Neither of the types was found among group A strains. Type 2b strains of serogroup B emerged in 1965, causing a country-wide epidemic which reached a peak incidence in March and April of 1966 and continued to predominate within group B until 1979. Type 2a strains of serogroup C were responsible for a substantial number of sporadic cases over a long period without any association with outbreaks or with a shift in the pattern of the serogroup. After the appearance of group W-135 in 1971, W-135 strains caused a small non-focal epidemic wave. The upsurge of disease due to virulent sub-populations of strains B:2b and C:2a appeared to be closely related to a basic pattern of regular cyclical waves with peak intervals which differed for serogroups A, B, and C. In recent years both serotype 2a and 2b strains within the different serogroups fell to insignificant numbers. Our results show that retrospective large-scale serotyping of collected strains provides insight into the epidemiological patterns of endemic meningococcal disease.

Antibodies, Bacterial↗
PubMed1986

Non-neonatal meningitis due to less common bacterial pathogens, the Netherlands, 1975-83.

In the Netherlands, case histories of 160 patients aged more than 1 month, with meningitis due to bacteria other than Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae were reviewed in order to look for associations between the bacteriological data and the course of disease. The incidence of such cases was about 0.8/100,000/year. Escherichia coli and Listeria monocytogenes each accounted for about 15% of the cases. The case-fatality rate was 18.8% (Gram-negative bacteria, 25%; Gram-positives, 15%) and sequelae occurred in 13.3% of the surviving patients (14 and 13% Gram-negative and Gram-positive, respectively). Hearing loss was the most prevalent sequela (5.0%). Predisposing factors were present in 70% of patients (69 and 71% respectively), especially in meningitis due to enteric Gram-negative bacteria (except for salmonella) and due to staphylococci. Surveillance is important because the incidence of meningitis due to these micro-organisms is likely to increase and because the problems in antibiotic treatment have not yet been solved.

Adolescent↗
PubMed1986

Bacterial meningitis in 366 children in the Netherlands, 1982-1983. Epidemiology and antibiotic therapy.

Records of 366 children 0-15 years with bacterial meningitis (April 1982-March 1983) were reviewed in the framework of a medical audit. The general epidemiological pattern and the antibiotics administered are described and the patients in general hospitals are compared with those in academic hospitals. H. influenzae has been isolated from 31% of patients, N. meningitidis from 23% and S. pneumoniae from 10%. Case-fatality ratio was 6.6% overall, but it was higher in disease due to rare pathogens like E. coli and group B-Streptococcus (up to 25%). These rare pathogens were more common among patients in academic than in general hospitals. However, this difference was not significant, nor were differences in age distribution or case-fatality ratio between the two hospital categories. As initial therapy chloramphenicol plus a penicillin were administered to 30% of patients. On the fifth day of treatment ampicillin was the most frequently used antibiotic in general hospitals (31%), but in academic centres the above-mentioned combination (27%) and penicillin alone (24%) were most popular. It is argued that new antibiotics need to be evaluated carefully. Because this necessitates several hundreds of patients, multi-centered randomised trials should be carried out.

Academic Medical Centers↗