What is the current status of management of the patient with exercise-induced asthma?

Exercise-induced asthma (EIA) is a very common and troublesome disease frequently impairing optimal athletic performance. Although described as early as the second century A.D. and widely known since 1972, EIA often goes unrecognized by both patient and physician. The goals of treatment are to minimize symptoms thus allowing the athlete to participate fully in a broad array of activities and to utilize the most effective pharmacologic drugs available. The recognition and treatment of exercise-induced asthma (EIA) have made significant progress since 1972 when United States swimmer, Rick Demont had his Olympic gold medal award rescinded because of traces of ephedrine were detected in his urine. Lessons from this episode paid dividends subsequently; in preparation for the 1984 Olympic games in Los Angeles, the U.S. Olympic Committee developed a screening program which identified 67 U.S. team members with EIA. Astoundingly, several of these world-class athletes did not realize they had asthma. Affected individuals were counseled on the prevention of asthma and also on the effective use of medications; 41 won medals in various competitions including track and field, wrestling, basketball, cycling, swimming and rowing. Despite this resounding success, many athletes at all levels of competition still suffer from unrecognized or under-treated EIA despite knowledge of the problem since the second century A.D.(ABSTRACT TRUNCATED AT 250 WORDS)

Topical nasal sprays: treatment of allergic rhinitis.

Topical nasal sprays, especially steroids, have regained favor as treatment for allergic rhinitis. Nasal steroids are widely used and are as safe and effective as antihistamines in controlling symptoms of rhinitis. However, if improperly used, steroids can have side effects. It is essential that patients learn correct techniques for administering nasal steroids and understand complications that can result from nasal steroid use. New steroid drugs, such as budesonide, tripedane and fluticasone, are being evaluated and will be available in the near future. Other topical drugs, such as cromolyn and ipratropium, are also effective. Over-the-counter decongestants are helpful in reducing nasal congestion and allowing other topical medicines to penetrate effectively into the nasal cavity, but their use should be limited to no more than three days. Prolonged use of topical nasal decongestants has no place in the treatment of allergic rhinitis and can be associated with significant side effects.

Activation and differentiation antigens on T cells of healthy, at-risk, and HIV-infected children.

We examined the T-lymphocyte phenotypes of 67 human immunodeficiency virus (HIV)-infected children (P-1 or P-2) and 65 age-matched, healthy, control children stratified into four groups from < 1 to > or = 5 years of age to determine expression of antigens associated with cell activation/differentiation. Immunophenotyping was performed by laser flow cytometry using two-color immunofluorescent labeling. Although the control children showed a decline in total CD4 cell percent with age, the HIV-infected children in all age groups showed significantly decreased CD4 cell numbers compared with the age-matched controls. However, the slope of the CD4 cell decline with age was not significantly different in HIV-infected and control children. The CD4 cell decrease in infected children was reflected in both the CD45RA+ (naive) and CD45RA- (memory) CD4 cell subsets, although the CD45RA+ cells were decreased in greater proportion. Results assessing CD4 cells for expression of the L-selectin (Leu8) molecule were similar to those for CD45RA. The overall CD8 cell percentage was significantly increased in HIV-infected children compared with controls in all age groups. This was due primarily to increases in CD8 cells that were CD38+, CD57+, HLA-DR+, or CD45RA-. In a retrospective analysis of data from 23 P-0 children, we compared phenotype results from 5 children who were HIV+ with those 18 who were HIV-. Although the phenotypic changes seen in the 5 HIV+ children paralleled those described above for P-1 and P-2 subjects, there was no significant difference in the values for HIV+ compared with HIV P-0 children. Although the phenotypic alterations described did not appear to be diagnostic markers in P-0 children, they may serve as useful adjuncts for the evaluation of HIV-infected children.

Antibody responses to bacteriophage phi X174 in patients with adenosine deaminase deficiency.

Adenosine deaminase (ADA) deficiency and its biochemical consequences cause severe combined immunodeficiency (SCID). Treatment strategies, designed to correct the biochemical abnormalities, include transplantation of matched bone marrow or haploidentical bone marrow stem cells, repeated partial exchange transfusions with frozen irradiated human red blood cells (RBC), or weekly injection of polyethylene glycol-modified bovine ADA (PEG-ADA). To evaluate the effect of these therapeutic options, we studied in vitro T-cell function and in vivo antibody responses to the T-cell-dependent neoantigen, bacteriophage phi X174, in 10 children with ADA-deficient SCID. In untreated patients, T-cell function was severely depressed, and only minute amounts of antibacteriophage antibody were produced. Transplantation of bone marrow from a matched sibling (one patient) or a phenotypically matched parent (one patient) resulted in a stable graft, normal T-cell function, and substantial but subnormal antibody titers to bacteriophage, with reduced memory and impaired switch from IgM to IgG. Patients receiving T-cell-depleted haploidentical bone marrow stem cells had markedly depressed antibody responses for as long as 3 years posttransplantation, despite rapidly improving T-cell function that became normal in two of four patients. Two methods of enzyme replacement were explored. During treatment with human RBC transfusions, antibody responses to bacteriophage were as severely depressed as in untreated ADA-deficient patients. Treatment with weekly injections of PEG-ADA resulted in normalization of T-cell numbers in all four patients, normal or near-normal T-cell function in two, and mildly but variably improved T-cell function in the other two patients. Quantitatively and qualitatively normal antibody responses to bacteriophage were observed in three of four patients. Assessment of antibody responses to immunization with bacteriophage phi X174 is a useful method to monitor humoral immune function in treated ADA-deficient patients and can be used to estimate when intravenous immunoglobulin (IVIG) prophylaxis may be safely discontinued.

Home-based immunoglobulin infusion therapy: quality of life and patient health perceptions.

Thirty-seven antibody-deficient patients who were participating in a multicenter trial evaluating home-based, self-administered IVIG therapy anonymously completed questionnaires regarding beliefs concerning health control, quality of life, and attitudes toward active participation in medical care. Their responses were compared with a group of 29 patients undergoing traditional IVIG therapy in a medical clinic setting. A subsample of the home-based group who later returned to clinic-based IVIG therapy allowed comparison of responses given by the same patients in both settings. Home-based therapy was preferred to clinic-based therapy. Independence, convenience, comfort, decreased disruption of activities, travel time, and costs were specific factors rated most favorably. On the Health Belief Questionnaires, patients preferred informed, self-involved medical care regardless of the setting for their IVIG treatments.

Treatment of adenosine deaminase deficiency with polyethylene glycol-modified adenosine deaminase.

We treated two children who had adenosine deaminase deficiency and severe combined immunodeficiency disease by injecting bovine adenosine deaminase modified by conjugation with polyethylene glycol. The modified enzyme was rapidly absorbed after intramuscular injection and had a half-life in plasma of 48 to 72 hours. Weekly doses of approximately 15 U per kilogram of body weight maintained plasma adenosine deaminase activity at two to three times the level of erythrocyte adenosine deaminase activity in normal subjects. The principal biochemical consequences of adenosine deaminase deficiency were almost completely reversed. In erythrocytes, adenosine nucleotides increased and deoxyadenosine nucleotides decreased to less than 0.5 percent of total adenine nucleotides. The activity of S-adenosylhomocysteine hydrolase, which is inactivated by deoxyadenosine, increased to normal in red cells and nucleated marrow cells. Neither toxic effects nor hypersensitivity reactions were observed. In vitro tests of the cellular immune function of each patient showed marked improvement, along with an increase in circulating T lymphocytes. Clinical improvement was indicated by absence of infection and resumption of weight gain. We conclude that from the standpoints of efficacy, convenience, and safety, polyethylene glycol-modified adenosine deaminase is preferable to red-cell transfusion as a treatment for adenosine deaminase deficiency. Patients with other inherited metabolic diseases in which accumulated metabolites equilibrate with plasma could benefit from treatment with the appropriate polyethylene glycol-modified enzyme.

Galactose inhibition of neonatal neutrophil function.

To investigate possible causes for the significantly increased incidence of sepsis observed in galactosemic neonates, the in vitro effect of galactose on neutrophil function in healthy newborns was studied. Neutrophils from 25 normal newborns and 23 normal adult volunteers were incubated with 100 mg of glucose per dl, 300 mg of galactose per dl and 300 mg of galactose plus 100 mg of glucose per dl, respectively. Tests for neutrophil function included chemiluminescence (CL), chemotaxis (CTX) and adherence. Neutrophil CL (measure of bactericidal activity) was significantly depressed by galactose in both adults (30.2%) and newborns (59.5%); however, neonatal neutrophil function (CL) was depressed to a much greater extent than in adults. CTX was also significantly depressed by galactose in newborns but not in adults. Supplementing the galactose-containing medium with glucose restored both CL and CTX function to normal in adults. However, only CTX was restored in newborns, while CL remained markedly depressed. Neutrophil adhesion, a function which is not energy-dependent, was not affected by galactose in both adults and newborns. These findings indicate that depressed neutrophil function by galactose or its metabolites may contribute to the high incidence of sepsis in galactosemic neonates.