Determinants of vaccine immunity in the cohort of human immunodeficiency virus-infected children living in Switzerland

BACKGROUND: Human immunodeficiency virus (HIV)-infected children are at increased risk of infections caused by vaccine preventable pathogens, and specific immunization recommendations have been issued. METHODS: A prospective national multicenter study assessed how these recommendations are followed in Switzerland and how immunization history correlates with vaccine immunity. RESULTS: Among 87 HIV-infected children (mean age: 11.1 years) followed in the 5 Swiss university hospitals and 1 regional hospital, most (76%) had CD4 T cells >25%, were receiving highly active antiretroviral treatment (79%) and had undetectable viral load (60%). Immunization coverage was lower than in the general population and many lacked serum antibodies to vaccine-preventable pathogens, including measles (54%), varicella (39%), and hepatitis B (65%). The presence of vaccine antibodies correlated most significantly with having an up-to-date immunization history (P<0.05). An up-to-date immunization history was not related to age, immunologic stage, or viremia but to the referral medical center. CONCLUSIONS: All pediatricians in charge of HIV-infected children are urged to identify missing immunizations in this high-risk population.

Vaccination of cystic fibrosis patients against Pseudomonas aeruginosa reduces the proportion of patients infected and delays time to infection

INTRODUCTION: Cystic fibrosis (CF) almost always leads to chronic airway infection with Pseudomonas aeruginosa. Despite advances in antibiotic therapy, after chronic infection rapid deterioration in lung function occurs, increasing morbidity and mortality. Prevention of infection by vaccination is desirable, but earlier trials produced disappointing results. The promising short term immunogenicity and safety of a new P. aeruginosa vaccine prompted us to evaluate its long term efficacy. We conducted a 10-year retrospective analysis of outcomes in a group of vaccinated patients. MATERIALS AND METHODS: In 1989-1990, 30 young children with CF, mean age 7 years, with no prior history of infection with P. aeruginosa, were vaccinated against P. aeruginosa with a polyvalent conjugate vaccine. We report the follow-up of 26 of these patients from 1989 to 2001. The patients were given yearly vaccine boosters. Comparisons were made with a CF patient control group matched for gender, age and, where possible, genetic mutation. Vaccinated patients and controls were attending a single CF clinic and received the same clinical management throughout the study period. Main outcomes were time to infection, proportion of patients infected, development of P. aeruginosa mucoid phenotype, lung function and body weight. RESULTS: The time to infection with P. aeruginosa was longer in the vaccination group than in the control group, and fewer vaccinated patients than controls became chronically infected (32% versus 72%; P < 0.001). The proportion of mucoid infections was higher in the control group (44%) than in the vaccinated group (25%). Patients >/=18 years of age at the end of the study had a lower mean forced expiratory volume at 1 s (FEV1) than did those 13-17 years of age, but this difference was small in the vaccinated group (73.6% versus 83.7%) compared with the controls (48.0% versus 78.7%). In the >/=18 year age category the mean FEV1% at 10 years was 73.6% (vaccinated) and 48.0% (controls) (P < 0.05). In the vaccinated group only 11 (44%) of 25 patients were underweight at the 10-year follow-up compared with 18 (72%) of 25 at the beginning of the study. In the control group 17 (68%) of 25 patients were underweight at 10-year follow-up compared with 16 (64%) of 25 at the beginning of the study. CONCLUSION: Regular vaccination of young CF patients for a period of 10 years with a polyvalent conjugate vaccine reduced the frequency of chronic infection with P. aeruginosa. This was associated with better preservation of lung function. Vaccinated patients gained more weight during the study period, a possible indication of an improved overall health status.

Hemostasis management in pediatric mechanical circulatory support

In a 9-year-old boy, bridging to transplantation was successful with an external biventricular device, the Berlin Heart Excor (Berlin Heart, Berlin, Germany), during a 7-month period. Main long-term complications consisted of infection and hypercoagulability with clotting inside the chambers necessitating six pump exchanges, but without thromboembolic events. This report reviews hemostasis monitoring and management of long-term mechanical circulatory support.

Once daily dosing of netilmicin in neonatal and pediatric intensive care

OBJECTIVE: To examine a once daily dosing regimen of netilmicin in critically ill neonates and children. DESIGN AND SETTING: Open, prospective study on 81 antibiotic courses in 77 critically ill neonates and children, hospitalized in a multidisciplinary pediatric/neonatal intensive care unit. For combined empiric therapy (aminoglycoside and beta-lactam), netilmicin was given intravenously over 5 min once every 24 h. The dose ranged from 3.5-6 mg/kg, mainly depending upon gestational and postnatal age. Peak levels were determined by immunoassay 30 min after the second dose and trough levels 1 h before the third and fifth dose or after adaptation of dosing. RESULTS: All peak levels (n = 28) were clearly above 12 mumol/l (mean 22, range 13-41 mumol/l). Eighty-nine trough levels were within desired limits (< 4 mumol/l) and 11 (11%) above 4 mumol/l, mostly in conjunction with impaired renal function. CONCLUSIONS: Optimal peak and trough levels of netilmicin can be achieved by once daily dosing, adapted to gestational/postnatal age and renal function.

Targeting Myc in pediatric malignancies of the central and peripheral nervous system

Myc family genes are often deregulated in embryonal tumors of childhood including medulloblastoma and neuroblastoma and are frequently associated with aggressive, poorly differentiated tumors. The Myc protein is a transcription factor that regulates a variety of cellular processes including cell growth and proliferation, cell cycle progression, differentiation, apoptosis, and cell motility. Potential strategies that either inhibit the proliferation-promoting effect of Myc and/or activate its pro-apoptotic function are presently being explored. In this review, we will give an overview of Myc activation in embryonal tumors and discuss current strategies aimed at targeting Myc for cancer treatment.

Gender modulates the expression of calcium-regulating proteins in pediatric atrial myocardium

A differential expression of sarcoplasmic reticulum calcium-ATPase (SERCA2a) and phospholamban (PLB) characterizes the remodeling process in heart failure and atrial arrhythmias in adult patients. Gender is known to modulate the course and prognosis of different forms of heart disease. We hypothesized that gender plays a role in molecular changes of myocardial calcium regulating components already in childhood. Moreover, we studied the influence of volume overloaded (VO) on SERCA2a and PLB in pediatric patients. Quantitative reverse transcription-polymerase chain reaction was used to measure mRNA expression of SERCA2a and PLB in atrial myocardium from 30 pediatric patients (12 girls, 18 boys). Eighteen patients had VO right atria, and 12 patients had not-overloaded atria (NO). Protein expression was studied by Western blot. In the entire population, SERCA2a and PLB expression was not different between girls and boys. If hemodynamic overload was taken into account, SERCA2a mRNA expression was significantly reduced in the VO group compared with the NO group (P = 0.021). The VO versus NO difference was restricted to boys, which corresponds to a highly significant interaction of gender versus VO status (P = 0.002). The PLB to SERCA2a protein ratio was significantly lower in girls (P = 0.028). The decrease in SERCA2a mRNA expression in VO atrial myocardium and the PLB to SERCA2a ratio of protein expression was modulated by gender in this pediatric population. To our knowledge, this study is the first to show the impact of gender on the differential expression of calcium-regulating components in pediatric cardiac patients.

Age-dependent suppression of SERCA2a mRNA in pediatric atrial myocardium

Differential expression of sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2a) and phospholamban (PLB) has been shown in heart failure and atrial arrhythmias. We investigated the influence of volume overload and age on their expression in pediatric atrial myocardium. Right atrial specimens from 18 children with volume overloaded right atrium (VO) and 12 patients without overload were studied. Each group was further divided into patients less than and older than 12 months of age. Only in the younger patients SERCA2a was significantly reduced in the VO group. In younger patients PLB mRNA level tended to be lower in VO. The PLB:SERCA protein ratio was significantly reduced in the VO group. Age itself did not influence the SERCA2a and PLB expression, if the hemodynamic overload was not taken into account. This study is the first to show a combined influence of volume overload and age on atrial SERCA2a expression.

Prevalence of retinal hemorrhages in pediatric patients after in-hospital cardiopulmonary resuscitation: a prospective study

Child abuse occurs in 1% of children in the United States every year; 10% of the traumatic injuries suffered by children under 5 years old are nonaccidental, and 5% to 20% of these nonaccidental injuries are lethal. Rapid characterization of the injury as nonaccidental is of considerable benefit to child protection workers and police investigators seeking to safeguard the child care environment and apprehend and prosecute those who have committed the crime of child abuse. Physically abused children present with a variety of well-described injuries that are usually easily identifiable. In some cases, however, particularly those involving children with the shaken baby syndrome, obvious signs of physical injury may not exist. Although external signs of such an injury are infrequent, the rapid acceleration-deceleration forces involved often cause subdural hematomas and retinal hemorrhages, hallmarks of the syndrome. Frequently, retinal hemorrhages may be the only presenting sign that child abuse has occurred. Complicating the interpretation of the finding of retinal hemorrhages is the belief by some physicians that retinal hemorrhages may be the result of chest compressions given during resuscitative efforts. The objective of this study is to determine the prevalence of retinal hemorrhages after inpatient cardiopulmonary resuscitation (CPR) in pediatric patients hospitalized for nontraumatic illnesses in an intensive care unit.