Pediatric Pulmonology

Bruce K. Rubin, M.D.(left) and Andrew Bush, M.D.

Pediatric pulmonary disease is a subspecialty borne of the increasing recognition that children with cystic fibrosis (CF) required complex specialty care. The first pediatric pulmonologists some 50 years ago were focused on the care and treatment of children with CF or tuberculosis (TB). This specialty has evolved so that the modern pediatric pulmonary specialist is a scientist who understands developmental physiology, genetic diseases, inflammation and immunity, and the changing of pharmacological response as children grow, as well as a clinician who cares for children with CF and TB still, but is now expected to be an expert in the care of children with asthma, chronic lung disease of the newborn (formerly bronchopulmonary dysplasia), sleep disorders, chronic ventilator management both within the hospital and at home, and the management of a large variety of individually uncommon respiratory conditions. As care has improved and many of these children now live into adulthood, it is critically important for the practicing pulmonary internist to be familiar with these diseases. It wasn't so long ago that few children with CF survived into adulthood, whereas today, nearly half of all patients with CF are over the age of 18. The origins of asthma, chronic obstructive pulmonary disease, and other common pulmonary diseases seen by internists probably reach back as far as infancy or even antenatally.

In this issue of Seminars in Respiratory and Critical Care Medicine we have asked an international group of pediatric pulmonary experts to write about emerging and controversial areas that will be of interest to our colleagues in pulmonary medicine. We have focused on cutting-edge controversy, not merely in pediatric pulmonology but also of relevance for adult chest physicians in the four broad areas of asthma, CF, respiratory infection, and interfaces between pediatric and adult chest disease.

Professors von Mutius and Le Souëf open by discussing recent investigations into the interaction between genetics and early environmental influences in the development of asthma and the changing face (and lungs) of asthma at different ages. This informs our understanding of this complex disease and may lead to important preventive strategies. Although there has been great hope that the early recognition and treatment of the inflammatory component of asthma may prevent long-term morbidity and airway remodeling, there are as yet no data that clearly support this attractive strategy. Drs. van Mastrigt, Gabriele, and de Jongste discuss the appropriate means to measure airway inflammation as a guide toward the therapy of asthma, emphasizing that exhaled nitric oxide measurements may mean something entirely different in infants, children, and adults. Drs. Saglani, Wilson, and Bush then review the controversial role of the use of inhaled corticosteroids in the youngest of infants and children with wheeze, clearly documenting that preschool wheeze is not a sign of airway steroid deficiency and does not mandate replacement therapy!

Chronic inflammation plays a role not only in asthma but also in CF, where it has been hypothesized that the absence of a functional CF transmembrane conductance regulator (CFTR) protein will lead to a hyperinflammatory state and predisposes to chronic airway infection and inflammation. Drs. Elston and Geddes highlight the two-edged sword of inflammation in CF. Drs. Tarran, Donaldson, and Boucher discuss evidence for the use of hypertonic saline in CF lung disease. Professor Elborn then reviews prevention and treatment strategies for the many nonpulmonary features of CF, including diabetes, bone disease, stress incontinence, liver disease, and infertility and what they mean in terms of the management of the child and adult with CF.

Drs. Davies and Rubin then discuss the treatment of emerging infection in CF and the implications of multiply drug resistant organisms on strategies for control of this disease. Many of the nontypical organisms first seen in the CF population seem to show up soon thereafter in other immunocompromised patients, including those in critical care units. Not only are we encountering unusual organisms that are resistant to most antibiotics, but even common organisms such as Pneumococcus and Staphylococcus appear to be transforming into ever more virulent and more resistant bacteria. Drs. Cremonesini and Thomson review the management of empyema as a problem that is becoming far more common with the emergence of these very virulent organisms. The results of treatment of empyema differ markedly between adults and children. Although thrombolytics appear to be ineffective in adults, in children, their documented effectiveness has transformed pediatric empyema from a surgical chest tube deficiency disease.

As more children with severe pulmonary disorders are living longer, internists are finding it necessary to provide care and support for these patients. Dr. Robin Deterding writes about the classification and diagnosis of childhood interstitial lung disease (chILD) and how this differs from interstitial lung disease in the adult. Dr. Simonds discusses respiratory support for the severely handicapped child with neuromuscular diseases, whereas Dr. Eber provides insight into the antenatal diagnosis of congenital thoracic malformations and the implication for early surgical intervention.

It has been said that the child is the father to the man. We are learning that events that occur in early childhood can have a profound impact throughout life. It is our hope that these articles will stimulate interest and investigation and that they will help our patients transition effectively from pediatric care to care by the pulmonologist internist. As guest editors, we have learned much from the authors, and we are grateful for their hard work and patience with us. We would also like to thank Joe Lynch, for asking us to undertake the agreeable task of putting this together; and we thank the publishers for their labors.