Evaluation of a diagnostic approach to pediatric interstitial lung disease.

OBJECTIVE: To evaluate the value of a systematic approach to the diagnosis of pediatric interstitial lung disease (ILD). METHODS: In this descriptive, observational, prospective study, we evaluated 51 children presenting with ILD of unknown etiology during a 3-year period. Specific clinical information regarding history, physical examination, diagnostic evaluation, and final diagnosis was recorded on each patient. RESULTS: A specific diagnosis was established by history and physical examination alone in 1 patient, noninvasive tests alone in 8 others, and invasive tests, including lung biopsy, in another 26. Of the remaining patients, 8 had a suggestive diagnosis, and 8 had no specific diagnosis. CONCLUSIONS: A systematic approach to the diagnosis of pediatric ILD is useful, and not all patients need lung biopsy for diagnosis.

Vocal cord dysfunction: don't mistake it for asthma.

Vocal cord dysfunction (VCD), with its symptoms of stridor, air hunger, and chest or throat tightness, occurs primarily in active adolescents and young adults and may mimic exercise-induced asthma. Suspicions of VCD will be borne out by a mostly inspiratory stridor, abrupt onset and resolution of symptoms, an unpredictable symptom pattern, and the failure of usual asthma medications to resolve attacks. Laryngoscopy during acute symptoms is the definitive diagnostic tool. Panting can often stop an attack, and preventive treatment consists of patient education, speech therapy, and, when needed, psychological measures.

Asthma in infants and small children.

The wheezy young child is a particularly challenging patient to treat. This article focuses on a diagnostic approach and some of the treatment issues peculiar to this age group. Specifically addressed are (1) the problem of differentiating asthma from wheezy bronchitis in babies and the clinical implications of this; (2) general concepts of treating babies in whom many commonly used drugs are not FDA approved; (3) inhalation therapy, especially the use of metered-dose inhalers with spacers; (4) the standard asthma drugs and their beneficial and adverse effects, with particular reference to inhaled steroids; and (5) the nonpharmacologic management of asthma. A brief discussion of long-term outcome is also included.

Pulmonary vascular disorders masquerading as interstitial lung disease.

During the acquisition of a series of 92 children with interstitial lung disease (ILD) over a 14 year period, a significant minority (8/92 or 9%) were initially diagnosed as having ILD, but were subsequently found to have a variety of arterial, venous, and/or capillary disorders that explained their initial pulmonary findings. This subgroup of patients has had a very high morbidity and mortality, with only three of eight patients currently surviving. The presentation, evaluation, and natural history of these eight children were reviewed. We developed a strategy of cardiac and pulmonary evaluation for children presenting with clinical and radiographic features of ILD that helped us to identify rapidly those with pulmonary vascular disorders.

Parental criticism and treatment outcome in adolescents hospitalized for severe, chronic asthma.

This pilot study investigated the relationship between parental criticism and medical treatment outcome across an inpatient hospitalization in 19 adolescents with severe, chronic asthma. Parental criticism toward their asthmatic adolescent was assessed using the Five Minute Speech Sample technique (FMSS) at the beginning of the adolescent's inpatient stay at a national asthma referral center. Those adolescents whose parents were rated as high in criticism on the FMSS were found to have greater improvement in their overall asthma severity, greater reduction in their steroid medication dose, and shorter lengths of stay in the hospital than those whose parents were rated as low in criticism. The adolescents whose parents were rated as high in criticism also showed lower compliance with their prescribed theophylline and oral steroid medication at admission than the low criticism group. These findings do not appear to be due to misdiagnosis secondary to the presence of vocal cord dysfunction or to the allergy status of the children. Clinical implications and possible causal mechanisms underlying these findings are discussed.

Increased lower airways responsiveness associated with sinusitis in a rabbit model.

The association between sinusitis and asthma has been clinically recognized, but its precise nature is controversial. We studied the relationship between sinusitis and lower airways function in a rabbit model of sterile maxillary sinusitis induced by the chemotactic complement fragment C5a des arg. Animals kept in a head-up position following experimental sinusitis demonstrated a significant increase in airways responsiveness (AWR) to histamine. In contrast, animals of which the sinuses were injected with a saline diluent and in which no sinus inflammation developed had no increase in AWR. Experiments were subsequently carried out to investigate some of the potential mechanisms for these observations. A group of rabbits in which a distal site of inflammation was induced did not demonstrate increased AWR. Likewise, when sinus inflammation was established but passage of fluid to the lower airways was prevented, either by intubation or by head-down positioning, there was no change in AWR. A fourth experiment was designed to decrease complement factor activity before placing the animals in a head-up position. This led to the same degree of increased AWR. Neither the histology nor the bronchoalveolar lavage data demonstrated significant lower airways inflammation in any group. We conclude that sterile sinusitis can increase lower airways responsiveness to histamine in a rabbit model. The most likely mechanism for this effect is the postnasal dripping of cells or cell products into the lower airway. The role of a nasobronchial reflex or inflammatory mediator absorption could not be demonstrated in this model.

Clinical spectrum of chronic interstitial lung disease in children.

To describe the clinical spectrum of interstitial lung disease in children, we reviewed our experience with 48 patients during a 12-year period. Most patients initially had typical findings of restrictive lung disease and hypoxemia. Growth failure or pulmonary hypertension or both were found in more than one third. Specific diagnosis, made in 35 patients (70%), most often required invasive studies, particularly open lung biopsy. Although the diagnostic yield from open lung biopsy was high, the diagnosis of many patients remained uncertain. Many different disorders were encountered. The response to corticosteroids, bronchodilators, and chloroquine was inconsistent. Six patients died, five within 1 year after the initial evaluation. The spectrum of pediatric interstitial lung disease includes a large, heterogeneous group of rare disorders associated with high morbidity and mortality rates.

Vitamin D metabolites in adolescents and young adults with cystic fibrosis: effects of sun and season.

To assess mineral metabolism in patients with cystic fibrosis and to study the effects of season and sunlight exposure on generation of vitamin D metabolites, we quantified serum levels of calcidiol and calcitriol, other measures of bone metabolism, and radiographic bone mass in 20 adolescents and young adults with CF and 20 age-matched normal volunteers. Levels of calcidiol were lower in patients with CF than in controls and lower in Massachusetts than in Arizona in both study groups. Controls in Arizona had higher (P less than 0.05) levels of calcitriol than in Massachusetts throughout the year. All control subjects in both states had higher levels of calcitriol than did patients with CF. Patients in Massachusetts had significantly lower levels of calcitriol in winter than in summer. Summer levels of calcitriol in CF were significantly higher in Massachusetts than in Arizona; during winter, lower levels were found in Massachusetts than in Arizona. Mean bone density in patients with CF was 88% and 89% of normal American standards in Massachusetts and Arizona, respectively. These data indicate a seasonal, sunlight-related influence on levels of vitamin D metabolites in patients with CF receiving approximately 1000 IU vitamin D per day. Older patients with CF with progressively diminishing sunlight exposure may be at increased risk for development of osteopenia. The detected radiographic abnormalities of bone mineralization may also be related to malabsorptive deficiencies of calcium and phosphorus.