Effects of anaerobic exercise on the immune system in eight- to seventeen-year-old trained and untrained boys.

OBJECTIVES: To determine the immunologic response to a brief bout of intense exercise in children and to determine the effects of prolonged activity and maturation level of the subjects on this response. STUDY DESIGN: We determined counts of leukocytes and their subsets, counts of lymphocytes and their subsets, and natural killer (NK) cell activity and cell number before and 3 and 60 minutes after a Wingate anaerobic test (WAnT) in 16 male swimmers (9 to 17 years of age) and 17 male nonswimmers (9 to 17 years of age). Subjects were also categorized by pubertal status based on Tanner staging and by level of physical activity. The Student t test and analysis of variance were used to determine statistical significance, with values expressed as mean +/- SEM. RESULTS: Three minutes after the WAnT, all children had increases in leukocytes (28%), lymphocytes (43%), and NK cells (395%) (p < 0.01). Swimmers had less baseline NK cell activity (54 +/- 6 cytolytic units) than nonswimmers (87 +/- 10 cytolytic units) after the WAnT (p < 0.01), although both groups showed an increase to similar levels of NK activity 3 minutes after exercise. Pubertal effects on these responses were not significant. CONCLUSIONS: Our results demonstrate transient leukocytosis, lymphocytosis, and increases in NK cell number and activity in 8- to 17-year-old boys after a brief bout of intense exercise. Formal athletic training appears to be associated with a lower baseline NK cell activity, and yet such activity is still within the normal range for this age group. Further investigations are necessary to determine the impact of such training on overall health and the ability to fight infection.

Chronic pancreatitis in a patient with cystic fibrosis and clinical pancreatic insufficiency.

Pancreatitis occurs in up to 15% of patients with cystic fibrosis and pancreatic sufficiency, but the possibility of its occurrence in patients with pancreatic insufficiency has not been recognized. We describe a patient with homozygous delta F508 cystic fibrosis and typical symptoms of pancreatic insufficiency (greasy, fatty stools) in whom pancreatitis developed.

Lipid levels in adults with cystic fibrosis.

OBJECTIVE: To examine the hypothesis that an energy-dense, high-fat diet, which is necessary to maintain weight in adults with cystic fibrosis, does not result in high serum cholesterol levels. DESIGN: Dietary, anthropometric, and biochemical data were correlated. SETTING: A cystic fibrosis center in Pittsburgh, Pa. SUBJECTS: Thirty-one adults with cystic fibrosis, 50 obligate carriers of the cystic fibrosis gene, and 26 controls who did not have cystic fibrosis. MAIN OUTCOME MEASURES: Adults with cystic fibrosis had a lower mean serum cholesterol level and higher mean intakes of energy and fat than controls. STATISTICAL ANALYSES PERFORMED: Student's t test was used to determine the statistical significance between two means. Univariate correlation coefficients were determined to measure the relative intensity of association between two variables. RESULTS: Mean total serum cholesterol levels in men with cystic fibrosis was 3.1 mmol/L vs 4.7 mmol/L in male controls (P < .001). Mean total serum cholesterol levels in women with cystic fibrosis was 3.2 mmol/L vs 4.3 mmol/L in female controls (P < .001). Three adults with cystic fibrosis and no signs of pancreatic insufficiency had serum cholesterol levels in the high normal range. Carriers had serum lipid levels in the same range as the controls. CONCLUSIONS/APPLICATIONS: The findings indicate that a high-energy, high-fat diet does not raise serum lipid levels in those patients with cystic fibrosis and pancreatic insufficiency. However, those individuals with cystic fibrosis and normal pancreatic function may be at the same risk as the general population for developing high serum lipid levels. They should have their serum lipid levels monitored and be given appropriate dietary recommendations.

Experience with pediatric lung transplantation.

Heart-lung transplantation and lung transplantation have become accepted techniques in adult patients with end-stage cardiopulmonary disease. We report here our experience between July 1985 and March 1993 with 34 children (< 20 years) who underwent heart-lung (n = 18) or lung transplantation (n = 17). Indications for transplantation included cystic fibrosis (n = 9), congenital heart disease with Eisenmenger complex (n = 9), primary pulmonary hypertension (n = 8), pulmonary arteriovenous malformations (n = 2), desquamative interstitial pneumonia (n = 2), Proteus syndrome with multicystic pulmonary disease (n = 1), graft-versus-host disease (n = 1), rheumatoid lung disease (n = 1), and bronchiolitis obliterans and emphysema (n = 1). Twenty-six patients (76%) have survived from 1 to 88 months after transplantation; most patients have returned to an active lifestyle. Of the eight deaths, four were due to infections, two to multiorgan failure, 1 to posttransplant lymphoproliferative disease, and one to donor organ failure. Four of the patients who died had cystic fibrosis. Despite considerable morbidity related to infection, rejection, and function of the heart-lung and lung allograft in some patients, our results with this potentially lifesaving procedure in the pediatric population have been encouraging.

The prognostic value of exercise testing in patients with cystic fibrosis.

BACKGROUND: Previous studies have shown female sex, impaired pulmonary function, older age, malnutrition, and colonization of the respiratory tract with Pseudomonas cepacia to be associated with a poor prognosis in patients with cystic fibrosis. We sought to determine the prognostic value of exercise testing in addition to the other prognostic factors. METHODS: A total of 109 patients with cystic fibrosis, 7 to 35 years old, underwent pulmonary-function and exercise testing in the late 1970s. They were followed for eight years to determine the factors associated with subsequent mortality. Survival rates were calculated with standard life-table methods. Cox proportional-hazards regression models were used to determine crude relative risks of mortality and relative risks adjusted for age, sex, body-mass index, forced expiratory volume in one second (FEV1) end-tidal partial pressure of carbon dioxide (PCO2) at peak exercise, and oxygen consumption at peak exercise (VO2 peak). RESULTS: Patients with the highest levels of aerobic fitness (VO2 peak, > or = 82 percent of predicted) had a survival rate of 83 percent at eight years, as compared with rates of 51 percent and 28 percent for patients with middle (VO2 peak, 59 to 81 percent of predicted) and lowest (VO2 peak, < or = 58 percent of predicted) levels of fitness, respectively. After adjustment for other risk factors, patients with higher levels of aerobic fitness were more than three times as likely to survive than patients with lower levels of fitness. Colonization with P. cepacia was associated with a risk of dying that was increased fivefold. Age, sex, body-mass index, FEV1, and end-tidal PCO2 at peak exercise were not independently correlated with mortality. CONCLUSIONS: Higher levels of aerobic fitness in patients with cystic fibrosis are associated with a significantly lower risk of dying. Although better aerobic fitness may simply be a marker for less severe illness, measurement of VO2 peak appears to be valuable for predicting prognosis. Further research is warranted to determine whether improving aerobic fitness through exercise programs will result in a better prognosis.

Pancreatitis in young children with cystic fibrosis.

Five young children with cystic fibrosis and abdominal pain were found to have pancreatitis. Diagnosis was delayed in four patients because of the belief that pancreatitis occurs only in older patients with cystic fibrosis. In one patient pancreatitis was diagnosed before cystic fibrosis and diagnosis of cystic fibrosis was delayed. Pancreatitis should be considered as a possible cause of abdominal pain in pancreatic-sufficient children with cystic fibrosis and cystic fibrosis should be considered as a possible cause of pancreatitis, even in the young child.

Exercise conditioning in children with asthma.

A controlled study of 20 children with asthma who participated in a 4-month running program (30 min/day, 3 days/wk), using inhalation of a beta-2 stimulant prior to each running session to prevent exercise-induced asthma, showed significant increases in work tolerance (120.5 +/- 45.0 W before, 131.5 +/- 43.5 W after, P = 0.002) and cardiopulmonary fitness (peak oxygen consumption 37.6 +/- 8.6 ml/kg/min before, 43.1 +/- 10.5 ml/kg/min after, P less than 0.001). Asthma severity judged by daily asthma diary scores and twice daily peak flows did not change. Thirteen control patients with asthma did not exercise and demonstrated no change in work tolerance, fitness, or severity of asthma. Thus, children with asthma can safely engage in a running program and can increase work tolerance and fitness without worsening their asthma.