Current Pediatric Reviews - Volume 8, Issue 1, 2012

Asthma is a chronic respiratory disease that affects 300 million individuals world-wide. Overall, in children and adolescents the prevalence ranges from 1.6 – 36.8%. The highest prevalence of this disease occurs in the U.K., New Zealand, Australia, and Ireland with ranges from 28-36%. An increase in the prevalence of asthma is associated with the westernization of developing countries. Asthma has become a leading public health concern due to the dramatic rise in the incidence of this disease over the past 15 years, particularly in minority populations. This special issue is devoted to the state of the science in pediatric asthma. Experts in the field have authored six articles related to the latest in clinical guidelines and the management of this disease in the pediatric population. The first article focuses on physiology by reviewing the complex airway in children with asthma. This article by Drs. Newcomb & Cauble discusses the inter-related components involved in asthma pathogenesis and its fundamental clinical features. New directions in research for the treatment of pediatric asthma are described. An update on asthma assessment in children is discussed by Dr. Sande Okelo. Referring closely to the Expert Panel 3 Guidelines, the diagnosis, assessment, and responsiveness to treatment are reviewed. Dr. Mona Tsoukleris and colleagues analyze research evidence regarding long-acting beta-agonist safety and specific step up and step down medication recommendations in children that have been published since the release of the Expert Panel 3 report (2007). Management of pediatric asthma includes addressing environmental factors to reduce exposure to allergens. Dr. Arlene Butz and colleagues describe the role of allergens such as dust mites, pets, cockroaches, mold, rodents, and second hand smoke as associated with asthma exacerbations. Best practices for control of these allergens are discussed.

This review seeks to broadly inform the general reader of current thinking regarding the inter-relating components involved in childhood asthma pathogenesis. A holistic approach, typical of the practicing clinician’s perspective is used, to catalog the major cell effectors and molecules involved in asmogenic processes. Developmental characteristics of infants and children that put them at increased risk for wheezing illnesses and asthma are briefly reviewed. Contemporary theories that purport to explain the emergence of asthma in children are discussed and their intersections are highlighted. Although the allergic paradigm remains privileged among asthma theories, its limitations are reviewed. Roles of major cell effectors and selected recent research on their roles in asthma are described, including mast cells, basophils, eosinophils, neutrophils, alveolar macrophages, and Th-2 lymphocytes. Characteristics of diverse molecules and their relationships with cells and each other are described. Fundamental clinical features of asthma are reviewed with recent relevant findings. New directions in research with promising potential for treatment are discussed.

The assessment of asthma in children is critical to determining when to start, stop and adjust daily antiinflammatory controller medications, and to achieving optimal asthma outcomes. Several key aspects of asthma management are discussed including; 1) establishing a diagnosis of asthma, 2) classifying asthma severity or control, 3) assigning treatment (e.g., determining which patients are in need of daily controller medications), and 4) evaluating how well a patient is responding to prescribed asthma therapy. Use of validated control measures has been encouraged in the 2007 EPR-3 NIH asthma guidelines as means of facilitating the assessment of asthma control. Several measures of asthma control are included for use in clinical practice.

Evidence regarding long-acting beta-agonist safety and specific step up and step down recommendations in children that have been published since the National Asthma Education Prevention Program Guidelines for the Diagnosis and Management Expert Panel Report 3 are reviewed. Despite several systematic reviews involving many thousands of patients, the safety of long-acting beta-agonists in children remains under debate. Although the role of inhaled corticosteroids has been well established in children, whether the ideal add on therapy should be a long-acting betaagonist or a leukotriene receptor antagonist, balancing efficacy with safety information, remains controversial. The ideal step down regimen to be used after asthma control has been achieved is similarly not well established. Additional research in children is needed to answer these questions, particularly in the youngest age groups.

Management of pediatric asthma requires addressing environmental factors to reduce exposure to allergens and particulate matter including second hand smoke (SHS), N02 and ozone. Because children spend 80-90% of their time indoors at home and school, the indoor environment is the primary target of prevention of exposures associated with asthma exacerbations. This review will identify factors both in the indoor and outdoor environment that are associated with asthma exacerbations and provide evidence-based recommendations to reduce these exposures.

School-age children face many challenges when a chronic illness is present. Understanding normal school-age development, including a need for increasing independence and mastery of skills, as well as cognitive ability, lay the foundation for teaching self-management skills to school-age children with asthma. The purpose of this paper is to highlight normal maturational development of school-age children that supports an approach to teaching them to manage their asthma, including promoting adherence to the child's treatment regimen. A new model for encouraging children's performance of the recommended self-management behaviors is proposed. This contingency management model, guided by cognitive social learning theory, is a set of behavioral strategies to support behavioral change for school-age children with asthma. Implementation of the model resulted in improved asthma treatment adherence and health outcomes for school-age children when the targeted self-management behavior was daily peak flow monitoring.

The increase in the prevalence, morbidity, and mortality of asthma in adolescents is a public health concern worldwide in both developed and developing countries. The personal, familial, and economic costs associated with this disease are high. The purpose of this article is to describe strategies to support asthma management that are developmentally appropriate and effective for teens. Such strategies can lay the foundation for continued positive asthma management into adulthood. Asthma education/management programs developed specifically for adolescents will be described. Recommendations to address barriers to adolescent asthma self-management will also be discussed.

Epilepsy surgery has become the major intervention for children as well as adults with pharmacologically resistant epilepsy. Drug resistant epilepsy is defined as failure of appropriate trials of two anticonvulsants which are appropriately chosen depending on the type of epilepsy and adequately prescribed for a reasonable length of time failed to achieve good seizure control [1]. Patients with lesion on their MRI and who have 2 to 3 anticonvulsants are less likely to respond to new pharmacological treatment. Since the last decade advances in technology and clearer identification of seizure focus leading to complete resection have tremendously improved outcomes especially in patients with identifiable lesions on MRI Brain [2, 3]. In this modern era, parents and clinicians should not see surgery as a last resort treatment [4]. Recent research has showed that more pediatric epilepsy patients are becoming seizure free after surgery. In fact, the data from the epilepsy centers support earlier surgical treatment results showing improved outcomes and children leading relatively normal lives [5]. The present series will provide the review up-to-date information of the readers about pediatric epilepsy, treatment options and about the recent advances in the field of pediatric epilepsy including the surgical treatment.

Accurately diagnosing pediatric patients with specific epilepsy syndromes remains a major challenge today. The diagnosis of epilepsy syndrome is established on the basis of the age of onset, type of epilepsy, progressive nature of the disease, interictal EEG abnormalities, gender predominance, precipitating factors, family history, neuropsychological features and prognosis. A diagnosis of pediatric epilepsy syndrome can be complicated by a number of factors and the established diagnosis affects the treatment options. Further, pediatric epilepsy patients respond differently to various treatments making prognosis difficult. Epilepsy syndromes are further divided into generalized, focal, undetermined and “special” syndromes based on the Committee on Classification and Terminology of the International League Against Epilepsy (1989). In this chapter, we will discuss the major epileptic syndromes seen in childhood and adolescence, their salient clinical features, ictal and interictal EEG characteristics, prognosis and treatment options.

Pediatric patients who have failed two or more medications are less likely to respond to medical management. Intractable epilepsy leads to neurological deterioration and cognitive deficits. In this modern age of new technology, it is better to evaluate these patients for early resection of the seizure focus. Patients with an identifiable lesion on imaging and a localized seizure focus detected during intensive seizure monitoring have much higher chances of seizure freedom than with medical management alone. It has also been shown that pediatric epilepsy surgery has improved the quality of life of patients and reduced burden on the caregivers. The selection of candidates for surgery includes a battery of tests. Inpatient video EEG monitoring and phase 2 intracranial EEG monitoring for precise seizure localization are the most important tests. The other tests include neuropsychological and WADA testing to predict and protect against any deficits in memory and language post surgery. Specialized epilepsy centers also have functional MRI (fMRI) to supplement the WADA test. Other specialized imaging techniques including brain MRI with seizure protocol, SPECT, interictal and Ictal SPECT and PET scans are utilized to identify the responsible lesions. Based on the results of the testing, patients can undergo epilepsy surgery. The most common epilepsy surgeries are temporal lobectomies, lesionectomies, extratemporal resections, corpus callosotomies, subpial transections and functional hemispherectomy. The decision regarding the type of epilepsy surgery depends on the localization of the seizure focus.

Intractable epilepsy can have a detrimental impact on children, increasing the likelihood of developmental delays and cognitive dysfunction, and negatively impacting quality of life. The goals of surgical intervention in pediatric epilepsy are multifactorial and include optimal seizure control and/or remission, improvement of functionality, and facilitation of brain development. Several factors contribute to post-surgical outcomes in children, which will be discussed in this article. Research findings suggest that surgical treatment can have a positive effect beyond seizure control, including improvements in cognition, academic skills, neurobehavioral functioning, and emotional state. An important emerging theme in the presented studies is advocacy for early surgical intervention in children. Future expansion of research in long-term pediatric surgery outcomes is necessary, especially regarding epilepsy in posterior brain regions, effect on academic performance, and impact on overall quality of life following surgery. Advances in structural and functional neuroimaging will contribute to greater understanding of the relationship between outcomes and plasticity.

A significant portion of pediatric epilepsy is intractable, resulting in a burden substantial enough to lead a family to choose surgical intervention. In recent years, advancements in clinical practice, technology, and pre-surgical evaluation procedures have improved post-surgical outcomes. In this short review, we highlight some of the pivotal advances in pediatric epilepsy surgery that have contributed to and continue to contribute to increased success rates.

In the US, epilepsy is credited with 2.75 deaths per 1 million people. This number is slightly lower in the UK at 1.79, but higher in Canada at 6.74. (4) Surgery for intractable epilepsy has been in use for hundreds of years, and in recent decades has demonstrated good success. However, many practitioners and the public still view surgery as a last resort, to be explored only after all possible medical therapy combinations have been exhausted and a good length of time has elapsed. Now, however, many major centers have begun to push surgery further and further to the front of their treatment paradigm, predicated on the discovery that medical refractiveness can be predicted after failure of just a few medications. (1) As collective experience grows, the idea that surgery should be planned early in the disease course is gaining momentum. Now that surgical success rates can top 80%percnt; in carefully selected cases (2), the American Academy of Neurology, in association with the American Epilepsy Society and American Association of Neurological Surgeons, after reviewing one class 1 and 24 class 4 studies, recommend referral to an epilepsy center so that patients can be expediently evaluated for surgery. (3) Not only is the length of preoperative disease decreasing in these patients, but they are becoming younger. This raises the question: how early is too early? Even if early intervention makes sense in adults, is there a minimum age for which this holds true? Does intervention before this age cause increased harm? Several studies examining this area were reviewed, which in combination demonstrate that seizure surgery in young patients is efficacious. At Dell Children%apos;s Medical Center, we advocate early evaluation and surgery for patients with medically refractory epilepsy who are candidates. In the last two years we have done 17 surgeries on patients under 4 years of age, 3 of which have been on patients under one year. Once a patient is deemed medically refractory with a high likelihood of surgical benefit and acceptable surgical risk, we will proceed with surgery regardless of age. Patient selection, however, requires the coordinated effort of a quality multidisciplinary team.