Impaired antibody memory to varicella zoster virus in HIV-infected children: low antibody levels and avidity*

OBJECTIVE

HIV-infected children have impaired antibody responses after exposure to certain antigens. Our aim was to determine whether HIV-infected children had lower varicella zoster virus (VZV) antibody levels compared with HIV-infected adults or healthy children and, if so, whether this was attributable to an impaired primary response, accelerated antibody loss, or failure to reactivate the memory VZV response.

METHODS

In a prospective, cross-sectional and retrospective longitudinal study, we compared antibody responses, measured by enzyme-linked immunosorbent assay (ELISA), elicited by VZV infection in 97 HIV-infected children and 78 HIV-infected adults treated with antiretroviral therapy, followed over 10 years, and 97 age-matched healthy children. We also tested antibody avidity in HIV-infected and healthy children.

RESULTS

Median anti-VZV immunoglobulin G (IgG) levels were lower in HIV-infected children than in adults (264 vs. 1535 IU/L; P<0.001) and levels became more frequently unprotective over time in the children [odds ratio (OR) 17.74; 95% confidence interval (CI) 4.36-72.25; P<0.001]. High HIV viral load was predictive of VZV antibody waning in HIV-infected children. Anti-VZV antibodies did not decline more rapidly in HIV-infected children than in adults. Antibody levels increased with age in healthy (P=0.004) but not in HIV-infected children. Thus, antibody levels were lower in HIV-infected than in healthy children (median 1151 IU/L; P<0.001). Antibody avidity was lower in HIV-infected than healthy children (P<0.001). A direct correlation between anti-VZV IgG level and avidity was present in HIV-infected children (P=0.001), but not in healthy children.

CONCLUSION

Failure to maintain anti-VZV IgG levels in HIV-infected children results from failure to reactivate memory responses. Further studies are required to investigate long-term protection and the potential benefits of immunization.

Molecular epidemiology of the nasal colonization by methicillin-susceptible Staphylococcus aureus in Swiss children

Nasal carriage of Staphylococcus aureus contributes to an increased risk of developing an infection with the same bacterial strain. Genetic regulatory elements and toxin-expressing genes are virulence factors associated with the pathogenic potential of S. aureus. We undertook an extensive molecular characterization of methicillin-susceptible S. aureus (MSSA) carried by children. MSSA were recovered from the nostrils of children. The presence of Panton-Valentine leukocidin (PVL), exfoliatins A and B (exfoA and exfoB), and the toxic-shock staphylococcal toxin (TSST-1) and agr group typing were determined by quantitative PCR. A multiple-locus variable-number of tandem repeat analysis (MLVA) assay was also performed for genotyping. Five hundred and seventy-two strains of MSSA were analysed. Overall, 30% were positive for toxin-expressing genes: 29% contained one toxin and 1.6% two toxins. The most commonly detected toxin gene was tst, which was present in 145 (25%) strains. The TSST-1 gene was significantly associated with the agr group 3 (OR 56.8, 95% CI 32.0-100.8). MLVA analysis revealed a large diversity of genetic content and no clonal relationship was demonstrated among the analysed MSSA strains. Multilocus sequence typing confirmed this observation of diversity and identified ST45 as a frequent colonizer. This broad diversity in MSSA carriage strains suggests a limited selection pressure in our geographical area.

H-ficolin serum concentration and susceptibility to fever and neutropenia in paediatric cancer patients

H-ficolin (Hakata antigen, ficolin-3) activates the lectin pathway of complement similar to mannose-binding lectin. However, its impact on susceptibility to infection is currently unknown. This study investigated whether the serum concentration of H-ficolin at diagnosis is associated with fever and neutropenia (FN) in paediatric cancer patients. H-ficolin was measured by time-resolved immunofluorometric assay in serum taken at cancer diagnosis from 94 children treated with chemotherapy. The association of FN episodes with H-ficolin serum concentration was analysed by multivariate Poisson regression. Median concentration of H-ficolin in serum was 26 mg/l (range 6-83). Seven (7%) children had low H-ficolin (< 14 mg/l). During a cumulative chemotherapy exposure time of 82 years, 177 FN episodes were recorded, 35 (20%) of them with bacteraemia. Children with low H-ficolin had a significantly increased risk to develop FN [relative risk (RR) 2.24; 95% confidence interval (CI) 1.38-3.65; P = 0.004], resulting in prolonged duration of hospitalization and of intravenous anti-microbial therapy. Bacteraemia occurred more frequently in children with low H-ficolin (RR 2.82; CI 1.02-7.76; P = 0.045). In conclusion, low concentration of H-ficolin was associated with an increased risk of FN, particularly FN with bacteraemia, in children treated with chemotherapy for cancer. Low H-ficolin thus represents a novel risk factor for chemotherapy-related infections.

Establishing glycaemic control with continuous subcutaneous insulin infusion in children and adolescents with type 1 diabetes: experience of the PedPump Study in 17 countries

AIMS/HYPOTHESIS

To assess the use of paediatric continuous subcutaneous infusion (CSII) under real-life conditions by analysing data recorded for up to 90 days and relating them to outcome.

METHODS

Pump programming data from patients aged 0-18 years treated with CSII in 30 centres from 16 European countries and Israel were recorded during routine clinical visits. HbA(1c) was measured centrally.

RESULTS

A total of 1,041 patients (age: 11.8 +/- 4.2 years; diabetes duration: 6.0 +/- 3.6 years; average CSII duration: 2.0 +/- 1.3 years; HbA(1c): 8.0 +/- 1.3% [means +/- SD]) participated. Glycaemic control was better in preschool (n = 142; 7.5 +/- 0.9%) and pre-adolescent (6-11 years, n = 321; 7.7 +/- 1.0%) children than in adolescent patients (12-18 years, n = 578; 8.3 +/- 1.4%). There was a significant negative correlation between HbA(1c) and daily bolus number, but not between HbA(1c) and total daily insulin dose. The use of <6.7 daily boluses was a significant predictor of an HbA(1c) level >7.5%. The incidence of severe hypoglycaemia and ketoacidosis was 6.63 and 6.26 events per 100 patient-years, respectively.

CONCLUSIONS/INTERPRETATION

This large paediatric survey of CSII shows that glycaemic targets can be frequently achieved, particularly in young children, and the incidence of acute complications is low. Adequate substitution of basal and prandial insulin is associated with a better HbA(1c).

Swiss recommendations for the management of varicella zoster virus infections

Infections with varicella zoster virus (VZV) are common viral infections associated with significant morbidity. Diagnosis and management are complex, particularly in immunocompromised patients and during pregnancy. The present recommendations have been established by a multidisciplinary panel of specialists and endorsed by numerous Swiss medical societies involved in the medical care of such patients (Appendix). The aim was to improve the care of affected patients and to reduce complications.

Serum levels of mannose-binding lectin and the risk of fever in neutropenia pediatric cancer patients

BACKGROUND

Fever in neutropenia (FN) is a frequent complication in pediatric oncology. Deficiency of mannose-binding lectin (MBL), an important component of innate immunity, is common due to genetic polymorphisms, but its impact on infections in oncologic patients is controversial. This study investigated whether MBL serum levels at cancer diagnosis are associated with the development of FN in pediatric cancer patients.

PROCEDURE

Serum MBL was measured using ELISA. Frequency, duration, and cause of FN were assessed retrospectively. Association with MBL level was analyzed using uni- and multivariate Poisson regression taking into account both intensity and duration of chemotherapy.

RESULTS

In 94 children, with a cumulative follow-up time of 81.7 years, 177 FN episodes were recorded. Patients with both very low MBL levels (<100 microg/L; risk ratio (RR), 1.93; 95% CI, 1.14-3.28; P = 0.014) and normal MBL levels (>or=1,000 microg/L; RR, P = 0.011) had significantly more frequent FN episodes than patients with low MBL levels (100-999 microg/L). Patients with very low MBL levels had significantly more episodes of FN with severe bacterial infection (bacteremia or pneumonia; RR, 4.49; 1.69 = 11.8; P = 0.003), while those with normal MBL levels had more FN episodes with no microbial etiology identified (RR, 1.85; 1.14 = 3.03; P = 0.014).

CONCLUSIONS

Very low MBL levels are associated with more frequent FN episodes, mainly due to severe bacterial infections. The surprising finding that children with normal MBL levels had more frequent FN episodes than those with low MBL levels needs testing in prospective studies.

[Lymphadenopathy and absences]

A 6-year-old boy presented with deterioration of general well-being during several weeks, headache and swelling of lymph nodes in the neck. In addition, the parents reported brief episodes resembling typical absence seizures. Serological tests and the examination of cerebrospinal fluid revealed neuroborreliosis. At the same time, electroencephalography showed characteristic patterns of absence epilepsy. The boy's condition improved rapidly during a 2-week course of intravenous ceftriaxone and after initiation of antiepileptic therapy. To our knowledge, absence epilepsy has not previously been reported in association with neuroborreliosis. We consider the two conditions to be coincidental.

Swiss recommendations for the management of varicella zoster virus infections

Infections with varicella zoster virus (VZV) are common viral infections associated with significant morbidity. Diagnosis and management are complex, particularly in immunocompromised patients and during pregnancy. The present recommendations have been established by a multidisciplinary panel of specialists and endorsed by numerous Swiss medical societies involved in the medical care of such patients (Appendix). The aim was to improve the care of affected patients and to reduce complications.

The prevalence of penicillin-non-susceptible Streptococcus pneumoniae among children aged < 5 years correlates with the biannual epidemic activity of respiratory syncytial virus

This study investigated whether the epidemiology of penicillin-non-susceptible pneumococci (PNSP) colonising small children correlated with the biannual epidemic activity of respiratory syncytial virus (RSV). Colonisation rates and the prevalence of PNSP among paediatric outpatients aged < 5 years was analysed between January 1998 and September 2003 using an established national surveillance network. Resistance trends were investigated using time-series analysis to assess the correlation with the biannual pattern of RSV infections and national sales of oral paediatric formulations of antibiotics and antibiotic prescriptions to children aged < 5 years for acute respiratory tract infections. PNSP rates exhibited a biannual cycle in phase with the biannual seasonal RSV epidemics (p < 0.05). Resistance rates were higher during the winter seasons of 1998-1999 (20.1%), 2000-2001 (16.0%) and 2002-2003 (19.1%), compared with the winter seasons of 1997-1998 (8.2%), 1999-2000 (11.6%) and 2001-2002 (9.5%). Antibiotic sales and prescriptions showed regular peaks during each winter, with no significant correlation with the biannual pattern of RSV activity and seasonal trends of PNSP. RSV is an important determinant of the spread of PNSP and must be considered in strategies aimed at antimicrobial resistance control.

Prävention der Frühsommer-Meningoenzephalitis (FSME)

Die aktive Immunisierung ist die einzige verfügbare Maßnahme, die zuverlässigen Schutz gegen die FSME vermittelt. Der Impfschutz dürfte bei über 95% liegen, FSME-Fälle bei korrekt Geimpften kommen aber vor. Neue Studien zeigen, dass die Dauer des Impfschutzes nach vollständiger Grundimmunisierung länger ist als bisher angenommen, und dass die meisten Personen ≥ 8 Jahre nach der letzten Dosis noch seropositiv sind. Die gültige Praxis von Auffrischimpfungen in Abständen von 3 Jahren ist deshalb Gegenstand aktueller Diskussionen. Bis zur Veröffentlichung neuer Empfehlungen kann, wenn vom Patienten gewünscht, als Alternative zur Auffrischimpfung eine FSME-IgG Titerbestimmung in Erwägung gezogen werden. Es wurde gezeigt, dass der Antikörpernachweis mit bestimmten kommerziellen ELISA Tests sehr gut mit dem Vorhandensein schützender Antikörper korreliert. Die FSME-Impfung ist in der Schweiz für alle Personen im Alter von über 6 Jahren empfohlen, die sich häufig in Zeckenbiotopen der bekannten FSME-Endemiegebiete aufhalten. Die Kosten der Impfung werden in dieser Indikation seit 2005 von den Krankenversicherern im Rahmen der obligatorischen Grundversicherung übernommen.

[Exanthema as a main symptom in the febrile child]

Distinguishing in febrile children between harmless rashes and those, which require specific action, is a common problem in pediatric primary care. Major exanthematous diseases necessitating emergency hospitalization include invasive meningococcal disease and rarely gram-negative septicaemia caused by other pathogens, staphylococcal and streptococcal toxic shock syndrome, endocarditis, fever and rash in travellers returning from tropical countries and drug hypersensitivity syndrome. Therapeutic intervention is also necessary in patients with scarlet fever, rheumatic fever, varicella in postpuberal and immunocompromised individuals, in Kawasaki's disease, in Still's disease and in other non-infectious, inflammatory diseases (e.g., familial mediterranean fever). Finally, various specific measures need to be taken in reportable diseases, erythema infectiosum (parvovirus B19), primary HIV infection and in Henoch-Schölein purpura.

Orbitale Komplikationen der pädiatrischen Rhinosinusitis: Konservative versus chirurgische Therapie und Analyse der Computertomografie

BACKGROUND

One of the most common complications of acute pediatric rhinosinusitis is orbital complication. For subperiosteal abscess, in particular, there are no generally accepted therapy recommendations.

PATIENTS

A retrospective study of 45 children with acute orbital rhinosinusitis complications, treated on an in-patient basis at the Department of ENT, Inselspital, University of Bern (1999-2004) is presented. The aim was to analyze conservative medical versus surgical treatment with regard to the individual stages of complications (according to the classification of Moloney, 1987) and, subsequently, to arrive at a therapy recommendation.

RESULTS

All children with preseptal cellulitis (stage I), 80 % of children with radiological a subperiosteal phlegmona (Stage IIA) and 67 % of the children with radiological a subperiosteal abscess (Stage IIB) could be treated conservatively. The child with the orbital cellulitis (Stage III) was treated surgically.

CONCLUSION

The preseptal cellulitis can be treated conservatively. We recommend an initial conservative therapy of 24 - 48 hours for subperiosteal phlegmona and subperiosteal abscess in the presence of normal vision. Surgical intervention should take place only if there is no improvement after this time interval. The orbital cellulitis should be treated primary surgically.

Frontotemporal dementia, semantic dementia, and Alzheimer's disease: the contribution of standard neuropsychological tests to differential diagnosis

CERAD-NAB (Consortium to Establish a Registry for Alzheimer's Disease-Neuropsychological Assessment Battery) data were compared between 51 patients with frontotemporal dementia, 13 with semantic dementia, and 69 with Alzheimer's disease. There were statistically significant differences between the 3 groups. Compared with patients with Alzheimer's disease, patients with frontotemporal dementia were more impaired on Animal Fluency but not on any other CERAD-NAB subtest. Patients with semantic dementia performed worse in Animal Fluency and Boston Naming Test compared with frontotemporal dementia and Alzheimer's disease. Multiple logistic regression analysis revealed that in the differentiation between frontotemporal dementia and Alzheimer's disease, the combination of Animal Fluency and Boston Naming Test correctly classified 90.5% of patients. In segregating semantic dementia and Alzheimer's disease, the combination of Boston Naming Test and Mini Mental State Examination resulted in a correct classification of 96.3%. These findings demonstrate that the Mini Mental State Examination and the language subtests of the CERAD-NAB are valuable clinical instruments for the differential diagnosis between early frontotemporal dementia, semantic dementia, and Alzheimer's disease.

Low incidence of respiratory syncytial virus hospitalisations in haemodynamically significant congenital heart disease

BACKGROUND

Haemodynamically significant congenital heart disease (CHD) is a risk factor for severe respiratory syncytial virus (RSV) disease in young children. Population based data on the incidence of RSV hospitalisations in CHD patients are needed to estimate the potential usefulness of RSV immunoprophylaxis using palivizumab.

AIMS

(1) To obtain population based RSV hospitalisation rates in children <24 months of age with CHD. (2) To compare these rates with non-CHD patients and with previous studies. (3) To determine the number of patients needed to treat (NNT) with palivizumab to prevent one RSV hospitalisation.

METHODS

Six year, longitudinal, population based study at an institution, which is the sole provider of primary to tertiary in-patient care for a precisely defined paediatric population.

RESULTS

RSV hospitalisation rates (per 100 child-years) in CHD patients aged <6, <12, 12-24, and <24 months of age were 2.5 (95% CI 0.8 to 5.6), 2.0 (0.8 to 3.8), 0.5 (0.1 to 1.8), and 1.3 (0.6 to 2.3), respectively, and the relative risk (RR) in comparison with non-CHD patients was 1.4 (0.6 to 3.1), 1.6 (0.8 to 3.2), 2.7 (0.7 to 9.7), and 1.8 (1.0 to 3.3), respectively. NNT was between 80 (35 to 245) and 259 (72 to 2140) for various age groups.

CONCLUSION

RSV hospitalisation rates in CHD patients were fourfold lower than reported from the USA. Based on these low rates and RR, unrestricted use of palivizumab does not appear to be justified in this study area.

Influenza-associated myositis in children

BACKGROUND

Influenza-associated myositis (IAM) is an infrequent and poorly known complication of influenza virus infection in children. The aim of this study was to describe five cases of IAM and to review the literature on IAM in children.

PATIENTS AND METHODS

We conducted a retrospective analysis of cases of IAM diagnosed at two university children's hospitals in Switzerland during two consecutive influenza seasons. Findings were compared with 39 individual case reports and five publications summarizing an additional 272 cases identified by a medical online library (MEDLINE) search.

RESULTS

Overall, 316 cases were analyzed. IAM typically occurred in school-aged children with a 2:1 male predominance. Influenza B and A viruses were identified in 76% and 24% of cases, respectively. The median interval between onset of influenza and onset of IAM was 3 days (range 0-18). The calf muscles were involved alone or together with other muscle groups in 69% and 31% of cases, respectively. Blood creatine phosphokinase (CPK) concentration was invariably elevated. Median duration to clinical recovery was 3 days (range 1-30). Rhabdomyolysis occurred in ten of 316 patients (3%), was more common in girls (80%), more often associated with influenza A (86%), and led to renal failure in eight patients (80%).

CONCLUSION

Clinical and laboratory findings of IAM are highly characteristic and allow a rapid diagnosis during the influenza season.

Two-year periodicity of respiratory syncytial virus epidemics in Switzerland

BACKGROUND

The annual respiratory syncytial virus (RSV) epidemics vary in time and severity. The aims of this study were (1) to describe the time-related pattern of RSV epidemics in Switzerland and (2) to deduce the most effective time period for administration of prophylactic measures to high-risk patients.

PATIENTS AND METHODS

Descriptive study of (1) RSV hospitalizations between 1997 and 2001 at a pediatric hospital serving a population of 1 million and (2) of national RSV detection rates reported by diagnostic laboratories between 1988 and 1999.

RESULTS

497 RSV hospitalizations and 8,574 reported RSV detections occurring during four and 12 epidemics, respectively, were analyzed. There was fixed alternation of minor and major epidemics differing in the number of RSV infections (two to fourfold), evolution (median interval from onset to peak 13 weeks, range 4-13 weeks vs 8 weeks, range 7-10 weeks; p = 0.065) and median duration (26 weeks, range 24-29 weeks vs 19.5 weeks, range 18-21 weeks; p = 0.005). For minor epidemics it was estimated that a maximum of 85.6% (range, 79.4-86.6%) of annual RSV infections could be covered by a standard five-dose regimen of the monoclonal anti-RSV antibody palivizumab, if initiated in week 50. During major epidemics the most effective time of initiation would be week 43 (88.7%; range 81.9-94.6%).

CONCLUSION

RSV epidemiology in Switzerland is characterized by fixed biannual variation. In the absence of active RSV surveillance, such periodicity is useful for scheduling RSV prophylaxis and for hospital resources management.

[Update on childhood immunization in Switzerland]

The recommendations for routine childhood immunizations undergo continuous re-evaluation and are periodically amended. As a result of the near complete elimination of wild-type poliomyelitis, the oral poliomyelitis live vaccine (OPV) has been replaced by the inactivated vaccine (IPV) for the primary series in infancy. Recent seroepidemiologic data on the dynamics of decay of maternal measles antibodies in infants may lead to the recommendation of administering the first dose of the measles mumps rubella (MMR) vaccine at twelve months rather than at 15 to 23 months of age. The recently introduced hexavalent vaccines for the primary series in infancy provide immunization against hepatitis B without the need for additional injections. Finally, the introduction of pneumococcal conjugate vaccines, which are highly efficacious in infants and young children, will provide the opportunity for successful prevention of vaccine-type invasive pneumococcal infections.

[Antimicrobial resistance--consequences for ambulatory treatment of infections in children]

Increasing antimicrobial resistance among clinical isolates of Streptococcus pneumoniae calls for a revision of treatment strategies for pediatric infections, particularly for acute otitis media. Restrictive use of antimicrobials is the key strategy for slowing the spread of resistances. Before initiation of antimicrobial therapy, suspected bacterial infections should be confirmed clinically (e.g. by observation of the natural evolution) or microbiologically. For acute otitis media, oral amoxicillin remains the drug of choice because of superior middle ear pharmacokinetics and pharmacodynamics. Treatment failure caused by resistance of the infecting pneumococcus can be overcome be increasing the dose, and not by switching to another class of antibiotics (e.g., cephalosporin, macrolide, cotrimoxazole), which is less likely to achieve middle ear eradication a priori. Widespread macrolide resistance among isolates of S. pneumoniae precludes the use of this class of antimicrobials for empiric therapy of community-acquired pneumonia in children. Aminopenicillins are preferred because of their rapidly bactericidal activity against the most common organisms causing potentially progressive pneumonia in children.

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

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.

Febrile seizures and parental anxiety: does information help?

AIM OF THE STUDY

To investigate the effect of febrile seizures on the behaviour and emotional situation of parents in order to improve our attitude towards these children and parents in future.

METHODS

We analysed 135 questionnaires on parents' behaviour and emotional situation during and after a febrile seizure in their children.

RESULTS

Febrile seizures were unknown to 44% of the parents. 121 parents (91%) reported severe anxiety on witnessing the first febrile seizure. In 69% the anxiety was so strong, that the parents believed their child would die. Severe anxiety was significantly associated with lack of knowledge about febrile seizures: 79% (no knowledge of febrile seizures) versus 59% (with knowledge). The level of anxiety appeared to be associated with low educational level, but not with ethnic background or income.

CONCLUSIONS

Our study shows that knowledge of febrile seizures among concerned parents in our region remains insufficient. The results are ambiguous. On the one hand we found an association between severe anxiety and lack of knowledge on febrile seizures, suggesting that information prior to the first febrile seizure might reduce the anxiety level and thus lead to appropriate reactions in case of recurrence. On the other hand although parents knew about febrile seizures, they still had very high anxiety levels and would react inappropriately in case of recurrence. Therefore if information is provided to parents, it must be specific, especially about which measures are to be taken or avoided respectively. A prospective study to observe positive and negative effects of preventive information is needed.

Febrile seizures and parental anxiety: does information help?

AIM OF THE STUDY

To investigate the effect of febrile seizures on the behaviour and emotional situation of parents in order to improve our attitude towards these children and parents in future.

METHODS

We analysed 135 questionnaires on parents' behaviour and emotional situation during and after a febrile seizure in their children.

RESULTS

Febrile seizures were unknown to 44% of the parents. 121 parents (91%) reported severe anxiety on witnessing the first febrile seizure. In 69% the anxiety was so strong, that the parents believed their child would die. Severe anxiety was significantly associated with lack of knowledge about febrile seizures: 79% (no knowledge of febrile seizures) versus 59% (with knowledge). The level of anxiety appeared to be associated with low educational level, but not with ethnic background or income.

CONCLUSIONS

Our study shows that knowledge of febrile seizures among concerned parents in our region remains insufficient. The results are ambiguous. On the one hand we found an association between severe anxiety and lack of knowledge on febrile seizures, suggesting that information prior to the first febrile seizure might reduce the anxiety level and thus lead to appropriate reactions in case of recurrence. On the other hand although parents knew about febrile seizures, they still had very high anxiety levels and would react inappropriately in case of recurrence. Therefore if information is provided to parents, it must be specific, especially about which measures are to be taken or avoided respectively. A prospective study to observe positive and negative effects of preventive information is needed.

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-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.

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.

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.

Myopericarditis associated with central European tick-borne encephalitis

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.

Staphylococcus aureus septicaemia in a patient with cystic fibrosis

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.

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.

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.

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.

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.

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.

Outbreak among drug users caused by a clonal strain of group A streptococcus

We describe an outbreak among drug users of severe soft-tissue infections caused by a clonal strain of group A streptococcus of M-type 25. Cases (n = 19) in drug users were defined as infections (mainly needle abscesses) due to the outbreak strain. Comparison with controls showed that infected drug users bought drugs more often at a specific place. Drug purchase and use habits may have contributed to this outbreak.

[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.

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.

Complications of varicella in a defined central European population

AIMS

To describe complications of varicella requiring hospitalisation in a defined population (canton of Bern) and to compare the hospitalisation rates for varicella with published data.

METHODS

Retrospective analysis of hospital records of patients less than 16 years of age admitted with complications of varicella to the hospitals serving this population (University Children's Hospital of Bern and the Wildermeth Children's Hospital of Biel, Switzerland), and calculation of hospitalisation rates for varicella and its complications based on birth rates and varicella antibody prevalence rates.

RESULTS

From 1986 to 1996, 113 cases (median age, 5.6 years) were identified. Younger siblings were overrepresented (odds ratio (OR), 1.42; 95% confidence interval (CI), 1.09 to 1.84). Central nervous system (CNS) complications (26 patients; 23%) were found predominantly in previously healthy children (relative risk, 7.1; 95% CI, 1.01 to 49.86). Group A beta haemolytic streptococci were recovered from only one of 35 patients with bacterial complications. The hospitalisation rates for primary varicella (9.2/10(4) cases; 95% CI, 7.4 to 11/10(4), skin infections (2.0/10(4) cases; 95% CI, 1.2 to 2.9/10(4), and pneumonia (0.8/10(4) cases; 95% CI, 0.3 to 1.3/10(4)) were significantly lower than reported previously. The CNS complication rate (2.2/10(4) cases; 95% CI, 1.3 to 3.1/10(4) was among the highest rates reported.

CONCLUSIONS

The low hospitalisation rate in comparison with studies from elsewhere indicates that there is a large regional variability in complications associated with varicella. Such data should be taken into consideration when local varicella immunisation strategies are developed.