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C Aebi

Publications and source records attributed to C Aebi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Age-specific seroprevalence to varicella-zoster virus: study in Swiss children and analysis of European data.

Up to date epidemiological data provide the rationale for potential varicella immunization strategies in Europe. The scope of this study was: (1) to generate new seroprevalence data by evaluating sera of 970 individuals aged 0-16 years for the presence of IgG against Varicella-zoster virus (VZV); and (2) to review existing seroprevalence data. Of 256 individuals >12 years of age, 96.1% (95% confidence interval [CI], 93.7-98.5) were seropositive. Swiss citizens > 12 years of age were less likely to be seronegative than foreign citizens (2.3 vs. 15.4%; odds ratio, 0.17; CI, 0.05-0.58). The age-specific seroprevalence curve demonstrated a peak at 7 years of age (84.9%; CI, 75.2-94.5) followed by lower rates at 8 and 9 years. A peak at 7-10 years of age was found in all previously reported seroprevalence curves (chi(2)-test for trend of pooled data, P = 0.09; Poisson analysis, P < 0.001). It is concluded that: (1) > 90% of individuals in Europe acquire immunity against VZV before adolescence; (2) there is no evidence for a recent upward shift of the age at primary varicella; and (3) there may be a north-to-south gradient of seroprevalence. The peak at 7-10 years may represent a transient loss of detectable antibody by some individuals.

Adolescent↗
PubMed2001

Regional impact of prophylaxis with the monoclonal antibody palivizumab on hospitalisations for respiratory syncytial virus in infants.

QUESTIONS: Palivizumab is approved in Switzerland for prevention of hospitalisation for RSV infection in children with one of the following risk factors: (1) history of prematurity < or = 35 weeks and age < or = 6 months or (2) chronic lung disease and age < or = 1 year. Regional data on the expected effectiveness of this monoclonal antibody are not available. METHODS: (1) Retrospective, descriptive, single-site study on the characteristics of RSV hospitalisations during two consecutive seasons. (2) Extrapolation of data to generate population-based estimates on the impact of palivizumb if used according to the approved indications. RESULTS: Of 242 RSV hospitalisations, 216 (89.3%) and 26 (10.7%) occurred in children without and with risk factors, respectively. Patients without and with risk factors had similar clinical courses with respect to ICU admission rate (11.6 vs. 11.5%) and rate of mechanical ventilation (3.2 vs. 3.8%). Of a total of 28 ICU admissions, 13 (46%) occurred among infants aged < or = 1 month without risk factors. Former premature infants were significantly older than patients with longer gestation (median age 7.5 vs. 3.7 months, p = 0.026). Applying the approved age criteria would have excluded 10 of 26 patients (38.5%) from eligibility for palivizumab. During the 1999/2000 RSV season, 36% of hospitalisations occurred after April 1, 2000. None of them may have been preventable had prophylaxis been started before November 1, 1999 and carried out for 5 months as recommended. In an annual birth cohort of 10,000, palivizumab as indicated would be expected to prevent between 5 and 7 RSV hospitalisations. CONCLUSIONS: The impact of palivizumab on the prevention of RSV hospitalisations in the Canton of Bern, Switerland, is expected to be small, and the approved indications may not target infants at greatest risk for severe disease.

Antibodies, Monoclonal↗
PubMed2001

Growth in human immunodeficiency virus type 1-infected children treated with protease inhibitors.

UNLABELLED: To determine the long-term impact of antiretroviral treatment (ART) including a protease inhibitor (PI) on growth in children infected with the human immunodeficiency virus type I (HIV-1), a prospective multi-centre study was conducted in Switzerland on HIV-1-infected children treated with ritonavir (350 mg/m2 twice a day) or nelfinavir (20-30 mg/kg three times a day) in addition to two nucleoside reverse transcriptase inhibitors. Length or height of HlV-1-infected children from before (weeks -72, -48, -24, and 0) and after (weeks +24, +48, and +72) introducing a PI to the ART were compared. To allow for age- and gender-independent assessment, values were expressed in standard deviations from the mean. Complete data sets on body length were available for 44 children after 72 weeks of treatment with a PI. Preceding initiation of a PI, there was an overall decline in growth to -0.3 SD. Following start of a PI, an increase in growth was noted from weeks 0 to +24 (+0.33 SD, P=0.02) and from weeks +48 to +72 (+0.21 SD, P=0.03). The increase in growth was restricted to children with stunting before a PI was introduced (P=0.03), and was more marked in children younger than 3 years of age. CONCLUSION: children infected with human immunodeficiency virus type 1 showed catch-up growth after addition of a protease inhibitor to their antiretroviral treatment, but this phenomenon was observed almost exclusively in children under 3 years of age.

Adolescent↗
PubMed2000

Myopericarditis associated with central European tick-borne encephalitis.

UNLABELLED: The case of an 11-year-old child with acute myopericarditis associated with central European tick-borne encephalitis is presented. Cardiac involvement was demonstrated by pericardial effusion, elevated serum concentration of troponin-I and cardiac arrhythmia. Co-infections with enteroviruses, Borrelia burgdorferi or the agent of human granulocytic ehrlichiosis were excluded. Recovery was uneventful. CONCLUSION: Central European tick-borne encephalitis can be complicated by cardiac involvement.

Arrhythmias, Cardiac↗
PubMed2000

Staphylococcus aureus septicaemia in a patient with cystic fibrosis.

UNLABELLED: Although bacterial colonisation of bronchi may occur from early childhood onwards, infections extending beyond the lungs are uncommon in patients with cystic fibrosis. A 12-year-old boy with cystic fibrosis, receiving oral corticosteroids for 3 weeks because of allergic bronchopulmonary aspergillosis, experienced pneumonia and septicaemia caused by Staphylococcus aureus. He was treated with flucloxacillin, ticarcillin-clavulanate, aztreonam, cefazolin and rifampin according to resistance testing of S. aureus cultured from the blood. On day 25 the patient finally had recovered. CONCLUSION: Systemic steroid therapy for allergic bronchopulmonary aspergillosis may favour life-threatening systemic bacterial infection which is rare in the immunocompetent patient with cystic fibrosis.

Child↗
PubMed2000

Long-term responses to treatment including ritonavir or nelfinavir in HIV-1-infected children. Pediatric AIDS Group of Switzerland.

BACKGROUND: Knowledge concerning the long-term antiretroviral and immunological efficacy of protease inhibitors in children is limited. PATIENTS AND METHODS: An open-label, prospective, multicenter clinical trial was conducted over a period of 72 weeks in Switzerland. 60 HIV-1 infected children (aged 0.3-16.9 years) naive to protease inhibitors were enrolled. Ritonavir or nelfinavir and at least one new nucleoside reverse transcriptase inhibitor were introduced into the current treatment regimen. HIV-1 RNA levels and CD4 cell counts were monitored after introducing the protease inhibitor, and the tolerability and safety of the drugs were assessed. RESULTS: Dictated by chronological availability, 37 children received ritonavir and 23 nelfinavir. At baseline, children given ritonavir had higher mean plasma HIV-1 RNA levels (5.03 vs 4.63 log10 copies/ml; p = 0.001) and lower mean CD4 cell counts (277 vs 555 cells/microl; p = 0.009) than children given nelfinavir. Antiretroviral treatment (ART) naive children showed higher mean plasma HIV-1 RNA levels than non-naive (5.18 vs 4.64 log10 copies/ml; p = 0.02). The decline in plasma HIV-1 RNA levels 72 weeks after treatment with ritonavir and nelfinavir was -2.17 and -1.30 log10 copies/ml, respectively (p = 0.006) and in ART-naive vs non-naive patients -2.70 vs -1.39 log10 copies/ml (p < or = 0.01). 69% of ART-naive patients and 32% of non-naive patients achieved sustained plasma HIV-1 RNA levels < 400 copies/ml. Increases in CD4 cells were higher in ART-naive compared to non-naive patients (p < 0.04). CONCLUSION: The antiretroviral and immunologic benefits of protease inhibitors are more profound in ART-naive than in non-naive children.

Adolescent↗
PubMed2000

Acute community-acquired diarrhea requiring hospital admission in Swiss children.

In order to ascertain the prevalence of agents that cause childhood diarrheal illness, stool specimens of 312 consecutive children with community-acquired diarrhea requiring admission were evaluated. Pathogens were detected in 166 (53%) of the 312 children (>/=2 pathogens in 28 children): Rotavirus (n=75), Salmonella spp. (n=37), Campylobacter spp. (n=24), Shigella spp. (n=5), Giardia spp. (n=4), Yersinia spp. (n=2), Aeromonas spp. (n=15), Cryptosporidium (n=15), enteropathogenic Escherichia coli (n=13), enterotoxigenic E. coli (n=7), and enterohemorrhagic E. coli (n=5). In conclusion, acute childhood diarrheal illness pathogens, such as Aeromonas, Cryptosporidium, and diarrheagenic E. coli, account for a large proportion of patients with a microbiologically positive stool specimen.

Adolescent↗
PubMed2000

Autoantibodies directed against bactericidal/permeability-increasing protein in patients with cystic fibrosis: association with microbial respiratory tract colonization.

BACKGROUND: Cystic fibrosis (CF) is associated with the appearance of serum autoantibodies directed against bactericidal/permeability-increasing protein (BPI). OBJECTIVES: To determine the age-specific seroprevalence rates of anti-BPI-IgG and IgA in a population of patients with CF and to correlate anti-BPI antibody concentrations with microbial respiratory tract colonization and pulmonary function variables at the time of serum sampling and 6 years thereafter. METHODS: Determination of BPI antibodies of the IgG and IgA isotypes using a commercial enzyme-linked immunosorbent assay in sera of a CF serum bank of 1992; correlation of anti-BPI antibody concentrations with age, clinical score, pulmonary function variables in 1992 and 1998, total serum immunoglobulin isotype concentrations and respiratory tract colonization with Pseudomonas aeruginosa and Aspergillus spp. RESULTS: Seventy-one patients (age in 1992, 14.1 +/- 7.5 years) were studied. Reactivities for anti-BPI-IgG and IgA were found in 28 (39%) and 26 (37%) patients, respectively. The seroprevalence of anti-BPI-IgA, but not IgG, increased significantly with age. P. aeruginosa colonization was associated with elevated concentrations of anti-BPI-IgG (P = 0.003) and IgA (P = 0.037). There were significant negative correlations between pulmonary function variables (vital capacity, forced expiratory volume in 1 s) in 1992 and 1998, respectively, and concentrations of anti-BPI-IgG or IgA in a multiple regression analysis. Anti-BPI-IgG, but not IgA, remained significantly associated with P. aeruginosa colonization (P = 0.006) and with reduced vital capacity (P = 0.01) in 1998 after correction for total serum isotype concentration. CONCLUSIONS: Anti-BPI-IgG are strongly associated with concurrent P. aeruginosa colonization and with long term restrictive pulmonary function abnormalities.

Adolescent↗
PubMed2000

The UspA1 protein and a second type of UspA2 protein mediate adherence of Moraxella catarrhalis to human epithelial cells in vitro.

The UspA1 and UspA2 proteins of Moraxella catarrhalis are structurally related, are exposed on the bacterial cell surface, and migrate as very high-molecular-weight complexes in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Previous analysis of uspA1 and uspA2 mutants of M. catarrhalis strain 035E indicated that UspA1 was involved in adherence of this organism to Chang conjunctival epithelial cells in vitro and that expression of UspA2 was essential for resistance of this strain to killing by normal human serum (C. Aebi, E. R. Lafontaine, L. D. Cope, J. L. Latimer, S. R. Lumbley, G. H. McCracken, Jr., and E. J. Hansen, Infect. Immun. 66:3113-3119, 1998). In the present study, isogenic uspA1, uspA2, and uspA1 uspA2 mutations were constructed in three additional M. catarrhalis strains: 012E, TTA37, and 046E. The uspA1 mutant of strain 012E had a decreased ability to attach to Chang cells. However, inactivation of the uspA1 gene in both strain TTA37 and strain 046E did not cause a significant decrease in attachment ability. Inactivation of the uspA2 gene of strain TTA37 did result in a loss of attachment ability. Nucleotide sequence analysis revealed that the predicted protein encoded by the uspA2 genes of both strains TTA37 and 046E had a N-terminal half that resembled the N-terminal half of UspA1 proteins, whereas the C-terminal half of this protein was nearly identical to those of previously characterized UspA2 proteins. The gene encoding this "hybrid" protein was designated uspA2H. PCR-based analysis revealed that approximately 20% of M. catarrhalis strains apparently possess a uspA2H gene instead of a uspA2 gene. The M. catarrhalis uspA1, uspA2, and uspA2H genes were cloned and expressed in Haemophilus influenzae cells, which were used to prove that both the UspA1 and UspA2H proteins can function as adhesins in vitro.

Amino Acid Sequence↗
PubMed2000

Early detection of lung disease and its association with the nutritional status, genetic background and life events in patients with cystic fibrosis.

Progression of lung disease is the most prominent cause of morbidity and death in patients with cystic fibrosis (CF), but the severity of lung disease and the rate of lung function decline are highly variable. An attempt was made to define accurate estimates of disease progression in these patients early diagnosed and prospectively evaluated until 10 years of age. The primary question to ask was whether functional abnormalities detected already in infancy are associated with functional derangements later on in life, and may be useful as parameters of prognostic value. Early diagnosis of CF can best be achieved by screening of mutation by new techniques (buccal cell brushing) in infants, even when the sweat test or accurate blood sampling is not available. Moreover, in infants lung function can be assessed by infant whole-body plethysmography enabling the study of the interrelationship with delayed weight gain and growth retardation, as well as the associations with the most common disease-causing mutations. Out of a cohort of 80 infants (39 males, 41 females) with CF a follow-up study was started with 50 CF infants diagnosed during infancy (mean age 4.6 +/- 4.0 months; range 0.1-12.7 months) and prospectively evaluated at 6-month intervals during the first 2 years of life. Moreover, in 32 CF children out of this cohort, follow-up was continued until 10 years of age. Differences were encountered with respect to the different events occurring during the first years of life, especially the onset of chronic colonization with Pseudomonas aeruginosa. The association between infant lung function and specific mutations (DeltaF508 homozygotes, frameshift DeltaF508/3905insT compound heterozygotes and nonsense DeltaF508/R553X compound heterozygotes) furthermore revealed that differences in lung function within the genetic groups are mainly related to the degree of pulmonary hyperinflation. Pulmonary hyperinflation was also associated with the degree of impaired nutritional status. An association between impaired gas exchange characteristics at 10 years of age and the degree of pulmonary hyperinflation during infancy finally demonstrates that by early mutation screening, lung function testing and assessment of the nutritional status predictors of disease progression later on in life can be defined. Therefore, preventive therapeutic measures should primarily be based on such prognostic factors.

Age Factors↗
PubMed1999

Diagnosis by polymerase chain reaction of pneumonia caused by Legionella pneumophila in an immunocompetent child.

A 10-year-old, previously healthy child with pneumonia caused by Legionella pneumophila diagnosed by polymerase chain reaction (PCR) of serum is presented. Diagnostic methods were PCR of serum using two different primer sets, and the detection of specific antibody in paired sera using an indirect immunofluorescence assay. Legionella DNA was amplified from serum obtained before and on day 6, but not after completion of a 14-day course of oral clarithromycin. The etiologic role of L. pneumophila was confirmed by seroconversion. The report illustrates that L. pneumophila PCR of serum may contribute to the identification of this microorganism as a cause of severe pneumonia in immunocompetent children.

Anti-Bacterial Agents↗
PubMed1999

[Infections in pregnancy].

Infections in pregnancy may complicate its course and harm the fetus or newborn after vertical transmission. Treatment of asymptomatic bacteriuria is mandatory in pregnant women given the high risk of secondary pyelonephritis. Intraamniotic infection usually arises by the ascending route and is associated with premature rupture of membranes. Vaginal infections promote preterm labour or premature rupture of membranes and may be transmitted to the child during labour. They must therefore be treated although they often cause little discomfort to the pregnant woman. Systemic infections due to viral, protozoal and bacterial pathogens may be transmitted transplacentally and cause embryopathies, fetopathies or neonatal infections. Depending on the responsible agent the negative impact on the course of pregnancy and on the fetus' or neonate's health can be prevented or reduced by prophylactic or therapeutic interventions.

Adult↗
PubMed1999

Characterization of the Moraxella catarrhalis uspA1 and uspA2 genes and their encoded products.

The uspA1 and uspA2 genes of M. catarrhalis O35E encode two different surface-exposed proteins which were previously shown to share a 140-amino-acid region with 93% identity (C. Aebi, I. Maciver, J. L. Latimer, L. D. Cope, M. K. Stevens, S. E. Thomas, G. H. McCracken, Jr., and E. J. Hansen, Infect. Immun. 65:4367-4377, 1997). The N-terminal amino acid sequences of the mature forms of both UspA1 and UspA2 from strain O35E were determined after enzymatic treatment to remove the N-terminal pyroglutamyl residue that had blocked Edman degradation. Mass spectrometric analysis indicated that the molecular mass of UspA1 from M. catarrhalis O35E was 83,500 +/- 116 Da. Nucleotide sequence analysis of the uspA1 and uspA2 genes from three other M. catarrhalis strains (TTA24, ATCC 25238, and V1171) revealed that the encoded protein products were very similar to those from strain O35E. Western blot analysis was used to confirm that each of these three strains of M. catarrhalis expressed both UspA1 and UspA2 proteins. Several different and repetitive amino acid motifs were present in both UspA1 and UspA2 from these four strains, and some of these were predicted to form coiled coils. Linear DNA templates were used in an in vitro transcription-translation system to determine the sizes of the monomeric forms of the UspA1 and UspA2 proteins from strains O35E and TTA24.

Amino Acid Sequence↗
PubMed1998

Metacarpal osteomyelitis complicating varicella-associated cellulitis of the hand: report of 2 cases.

Hematogenous osteomyelitis is a known complication of varicella. Osteomyelitis accompanying adjacent soft tissue infection, however, has only been described once in the literature. We report 2 cases of metacarpal osteomyelitis complicating varicella-associated cellulitis of the hand. The cases illustrate that this diagnosis should be considered in a patient with varicella, soft tissue infection and lack of clinical improvement despite apparently appropriate therapy.

Cellulitis↗
PubMed1998

Mapping of a protective epitope of the CopB outer membrane protein of Moraxella catarrhalis.

A monoclonal antibody (MAb) (MAb 10F3) directed against the CopB outer membrane protein of Moraxella catarrhalis previously was found to enhance pulmonary clearance of M. catarrhalis in an animal model (M. Helminen, I. Maciver, J. L. Latimer, L. D. Cope, G. H. McCracken, Jr., and E. J. Hansen, Infect. Immun. 61:2003-2010, 1993). In the present study, this same MAb was shown to exert complement-dependent bactericidal activity against this pathogen in vitro. Nucleotide sequence analysis of the copB gene from two MAb 10F3-reactive and two MAb 10F3-unreactive strains of M. catarrhalis revealed that the deduced amino acid sequences of these four CopB proteins were at least 90% identical. Comparison of the amino acid sequences of these proteins allowed localization of possible MAb 10F3 binding sites to five relatively small regions of the CopB protein from M. catarrhalis O35E. When five synthetic peptides representing these regions were tested for their ability to bind MAb 10F3 in a direct enzyme-linked immunosorbent assay system, an oligopeptide containing 26 amino acids was shown to bind this MAb. The actual binding region for MAb 10F3 was localized further through the use of overlapping decapeptides that spanned this 26-mer. A fusion protein containing the same 26-mer readily bound MAb 10F3 and was used to immunize mice. The resultant antiserum contained antibodies that reacted with the CopB protein of the homologous M. catarrhalis strain in Western blot analysis and bound to the surface of both homologous and heterologous strains of M. catarrhalis.

Adult↗
PubMed1998

Phenotypic effect of isogenic uspA1 and uspA2 mutations on Moraxella catarrhalis 035E.

The UspA surface antigen of Moraxella catarrhalis was recently shown to be comprised of two different proteins (UspA1 and UspA2) which share an internal region containing 140 amino acids with 93% identity (C. Aebi, I. Maciver, J. L. Latimer, L. D. Cope, M. K. Stevens, S. E. Thomas, G. H. McCracken, Jr., and E. J. Hansen, Infect. Immun. 65:4367-4377, 1997). Isogenic uspA1, uspA2, and uspA1 uspA2 mutants were tested in a number of in vitro systems to determine what effect these mutations, either individually or together, might exert on the phenotype of M. catarrhalis 035E. Monoclonal antibodies specific for UspA1 or UspA2 were used in an indirect antibody accessibility assay to prove that both of these proteins were expressed on the surface of M. catarrhalis. All three mutants grew in vitro at the same rate and did not exhibit autoagglutination or hemagglutination properties that were detectably different from those of the wild-type parent strain. When tested for the ability to adhere to human epithelial cells, the wild-type parent strain and the uspA2 mutant readily attached to Chang conjunctival cells. In contrast, the uspA1 mutant and the uspA1 uspA2 double mutant both attached to these epithelial cells at a level nearly 2 orders of magnitude lower than that obtained with the wild-type parent strain, a result which suggested that expression of UspA1 by M. catarrhalis is essential for attachment to these epithelial cells. Both the wild-type parent strain and the uspA1 mutant were resistant to the bactericidal activity of normal human serum, whereas the uspA2 mutant and the uspA1 uspA2 double mutant were readily killed by this serum. This latter result indicated that the presence of UspA2 is essential for expression of serum resistance by M. catarrhalis.

Animals↗