Oral versus intravenous corticosteroids in children hospitalized with asthma

BACKGROUND: Previous studies have demonstrated that in the emergency treatment of an asthma exacerbation, corticosteroids used in conjunction with beta-agonists result in lower hospitalization rates for children and adults. Furthermore, orally administered corticosteroids have been found to be effective in the treatment of outpatients with asthma. However, similar data in inpatients is lacking. OBJECTIVE: The purpose of this study was to determine the efficacy of oral prednisone versus intravenous methylprednisolone in equivalent doses for the treatment of an acute asthma exacerbation in hospitalized children. METHODS: We conducted a randomized, double-blind, double-placebo study comparing oral prednisone at 2 mg/kg/dose (maximum 120 mg/dose) twice daily versus intravenous methylprednisolone at 1 mg/kg/dose (maximum 60 mg/dose) four times daily in a group of patients 2 through 18 years of age hospitalized for an acute asthma exacerbation. All patients were assessed by a clinical asthma score 3 times a day. The main study outcome was length of hospitalization; total length of stay and time elapsed before beta-agonists could be administered at 6-hour intervals. Duration of supplemental oxygen administration and peak flow measurements were secondary outcome measures. RESULTS: Sixty-six patients were evaluated. Children in the prednisone group had a mean length of stay of 70 hours compared with 78 hours for the methylprednisolone group (P =.52). Children in the prednisone group were successfully weaned to beta-agonists in 6-hour intervals after 59 hours compared with 68 hours for the methylprednisolone group (P =.47). Patients receiving prednisone required supplemental oxygen for 30 hours compared with 52 hours for the methylprednisolone group (P =.04). CONCLUSION: There was no difference in length of hospital stay between asthmatic patients receiving oral prednisone and those receiving intravenous methylprednisolone. Because hospitalization charges are approximately 10 times greater for intravenous methylprednisolone compared with oral prednisone, the use of oral prednisone to treat inpatients with acute asthma would result in substantial savings.     

Levels of soluble IL-2 receptor in plasma from asthmatics. Correlations with blood eosinophilia, lung function, and corticosteroid therapy.

Evidence now suggests that eosinophils and T lymphocytes infiltrating bronchial tissues may play a key role in the pathophysiology of asthma. Circulating eosinophils, lung function, and plasma soluble IL-2 receptor (sIL-2R) were measured in 42 asthmatic patients referred for symptomatic asthma. The patients were divided into two groups based on the presence or absence of atopy. The group of non-atopic asthmatics was further divided according to the patients' requirement for long term oral corticosteroids. The mean sIL-2R +/- s.d. was 36.3 +/- 9.9 pM in the control group, 28.9 +/- 9.2 pM in the atopic asthmatics, 43.3 +/- 18.07 pM in the non-atopic asthmatics without oral steroid therapy, but was increased in the steroid-treated group (62.2 +/- 19.3 pM, P less than 0.01). A significant correlation was found between FEV1 and circulating eosinophils in atopic asthmatics and in non-atopic asthmatics without oral corticosteroid therapy, but not in the steroid-treated group. Furthermore, significant correlations were found between sIL-2R and FEV1, and between sIL-2R and blood eosinophils, in the group of non-atopic asthmatics not on oral steroid therapy. No such correlations were evidenced in the other groups of asthmatics. Similar results were obtained during the clinical course of three non-atopic patients followed for more than 1 year. These data suggest that T cell activation appears more prominent in non-atopic asthma than in atopic asthma. Moreover, it appears that T cell activation can occur in severe forms of asthma despite steroid treatment. Finally, the results suggest a possible link between T cell activation, eosinophils, and lung function, which may reflect a particular pathogenetic mechanism involved in non-atopic asthma.     

Methylprednisolone pulse therapy in severe acute asthma

In a group comparative double blind pilot study six asthmatic patients with an acute exacerbation of their disease were randomly treated with either methylprednisolone pulse therapy (MPPT) (1000 mg daily for 3 days) (n = 2) followed by placebo tablets, or standard doses of methylprednisolone (MP) (50 mg daily gradually decreased to zero over 3 weeks) (n = 4). The results showed that the effect of MPPT did not differ from that of standard doses of MP. MPPT has, however, the potential of being preferable to standard treatment with MP, because of easy administration and optimal patient compliance.     

The effectiveness of high-dose inhaled budesonide therapy in the treatment of acute asthma exacerbations in children.

BACKGROUND: International guidelines recommend the use of systemic steroids for the treatment of acute asthma attack if it has not been resolved within 24 to 36 hours of home management with regular beta2 mimetic inhalation. Such therapy for infrequent exacerbations is unlikely to have serious systemic effects. Unfortunately, many patients receiving frequent courses are potentially at risk for corticosteroid-induced side effects such as adrenal suppression, depression of linear growth, and osteoporosis. OBJECTIVE: To decrease the use of frequent oral corticosteroid courses in children, this study was designed to evaluate the efficacy of high-dose inhaled steroids in comparison with oral steroids, in the therapy of acute asthma exacerbations in children. METHODS: Sixty children who have experienced an acute exacerbation of asthma unresponsive to home management with regular use of inhaled beta2 mimetics, yet not severe enough to hospitalize, were randomized to be treated with either high-dose inhaled budesonide (1,600 microg daily) or oral methylprednisolone (1 mg/kg daily) plus medium-dose inhaled budesonide (800 microg daily, both in addition to inhaled terbutaline, 2,000 microg daily). Pre- and posttreatment pulmonary index scores, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), FEV1/FVC and forced expiratory flow 25% to 75% (FEF25%-75%) were evaluated. RESULTS: The mean number of decrease in pulmonary index score was 2.61 +/- 1.12 in the high-dose budesonide-receiving group (group I) and 1.90 +/- 1.08 in the oral steroid-receiving group (group II). There was a statistically significant difference between the two groups, in favor of group I (P = .038). No statistically significant difference was detected between the two groups with respect to the increase in lung function test measurements (FEV1, FEV1/FVC, FEF25%-75%; P = .790, .959, .819, respectively). CONCLUSIONS: Short-term high-dose budesonide therapy can be considered an alternative for children who are experiencing an acute asthma attack that is unresponsive to home management with regular use of an inhaled beta2 mimetic, yet who are not severe enough to hospitalize.     

Methotrexate therapy in asthma increases T cell susceptibility to corticosteroid inhibition

BACKGROUND: Concomitant methotrexate (MTX) therapy of severe, oral corticosteroid-dependent asthmatics has been shown to be corticosteroid sparing, but the mechanism is unknown. We hypothesized that MTX therapy of these patients increases the susceptibility of their T cells to corticosteroid inhibition. OBJECTIVE: To measure prednisolone inhibition of lectin-induced proliferation of peripheral blood T cells from a group of these patients before, during and following MTX therapy. METHODS: Eighteen severe asthmatics (median (range) age 56 (33-68) years, FEV1 61 (38-69)% predicted, dependent on oral prednisolone 15 (7.5-25) mg/day in addition to high-dose, inhaled corticosteroids) were treated with MTX 15 mg intramuscularly, weekly for 28 weeks. After 12 weeks of MTX, oral prednisolone dosages were reduced systematically over 16 weeks, provided that asthma control did not deteriorate. Patients were followed for a further 12 weeks after MTX withdrawal. Concentration-dependent, prednisolone inhibition of lectin-induced proliferation of peripheral blood T cells was measured just prior to MTX therapy (week 1) and at weeks 12, 28 and 40, and IC50 concentrations were interpolated. RESULTS: By week 28 of MTX therapy, patients were able to reduce oral prednisolone dosages from (median, SIQR) 15 (10-20.5) to 5.9 (1.4-9.4) mg/day (P<0.01) without alteration of lung function and symptoms, while median IC50 values for prednisolone inhibition of peripheral blood T cell proliferation were reduced from 49 (21-144) to 4 (1-9) nm (P<0.0001). These increased again to 15 (9.4-25.7) mg/day and 36 (18-67) nm, respectively, following MTX withdrawal. A correlation (P<0.01) was observed between percentage reductions in prednisolone dosages in vivo and fold changes in prednisolone IC50in vitro between weeks 12 and 28. CONCLUSION: This effect of MTX may at least partly account for its oral corticosteroid-sparing effect in severe asthma.     

Bronchial inflammation in corticosteroid-sensitive and corticosteroid-resistant asthma at baseline and on oral corticosteroid treatment

BACKGROUND: Pathophysiology of corticosteroid (CS)-resistant asthma remains incompletely understood. OBJECTIVE: To determine if failure of asthma to clinically improve with CS is due to a defective response of airway bronchial inflammation to these drugs. METHODS: Twenty-one asthmatics having a decreased baseline FEV1 that improved >or= 30% with inhaled beta2 agonist got bronchial biopsies before and at the end of an oral CS treatment (methylprednisolone 40 mg daily for 14 days). They were arbitrarily divided into two groups according to baseline FEV1 improvement following this treatment: >or= 23% designated as CS-sensitive (CSS) (n = 10) and < 15% as CS-resistant (CSR) (n = 11). RESULTS: Before oral CS, counts of bronchial mucosa inflammatory cells identified by immunohistochemistry (CD3, MBP, tryptase, CD68, neutrophil elastase and CD25 for lymphocytes, eosinophils, mast cells, macrophages, neutrophils and IL-2 receptors, respectively) were similar in CSS and CSR subjects. Oral CS decreased CD3+ cell counts (medians: 60-20 cells/mm(2); P = 0.014) and MBP+ cell counts (medians: 19-4 cells/mm(2); P = 0.03) in CSS asthmatics, but only tryptase+ cell counts in CSR asthmatics (medians: 30-18 cells/mm(2); P = 0.05). Few bronchial neutrophil elastase+ cells were observed and their counts were similar in the two groups of asthmatics before and when on oral CS (all medians: = 2 cells/mm(2)). CONCLUSIONS: These data show that, in these subjects with moderate to severe asthma, lymphocytes and eosinophils constitute most of the inflammatory cells infiltrating the bronchial mucosa. They also demonstrated that clinical impaired response to CS is associated with a persistent bronchial mucosa cellular infiltrate despite oral CS treatment. Additional studies are required to determine the role of this CS-resistant bronchial inflammation in the impaired asthma clinical response to these drugs.     

Near-fatal asthma phenotype in the ENFUMOSA Cohort

BACKGROUND: Near-fatal asthma (NFA) is characterized by severe asthma attacks usually requiring intensive care unit admission. This phenotype of asthma has been studied mainly in acute conditions. METHODS: The aim of our study was to compare the clinical, functional and inflammatory characteristics of NFA patients with mild to severe asthmatics in stable conditions. We recruited 155 asthmatic patients from five centres of the European Network for Understanding Mechanisms of Severe Asthma: 67 patients with mild-to-moderate asthma controlled by low/medium doses of inhaled corticosteroids; 64 with severe asthma that, despite treatment with high doses of inhaled corticosteroids, long-acting beta2-agonists and for 1/3 also with regular oral corticosteroids, had at least one asthma exacerbation in the previous year; 24 with an NFA episode in the previous 5 years in the absence of inclusion criteria for the previous groups. All the patients were examined in stable conditions. RESULTS: NFA patients were taking less corticosteroids and were less compliant to prescribed asthma medications than the other two groups of patients. Lung function, blood gases, atopic status, sputum and blood inflammatory cell count of NFA patients were similar to mild-to-moderate, but not severe, asthmatic patients. CONCLUSIONS: In stable conditions patients with an NFA attack in the previous 5 years cannot be distinguished from patients with mild-to-moderate asthma, while they are different from severe asthmatics both in terms of lung function and of airway inflammation. The risk factor that characterizes this group of patients is reduced usage of prophylactic corticosteroids.     

The use of ketotifen in the prophylaxis of seasonal allergic asthma

This double-blind parallel group study evaluated ketotifen 1 mg bid versus placebo in the treatment of 30 adult seasonally allergic asthmatics during the course of the spring pollen season. Those individuals on placebo had a fall in FEV1 through the pollen season, those on Ketotifen generally did not, and some individuals, in fact, showed improvement. Those patients receiving ketotifen had fewer allergic symptoms, better exercise tolerance, and in general had a better spring. This study demonstrated that ketotifen may have some benefit in the treatment of adult allergic asthma.     

Corticosteroid-resistant chronic asthma and monocyte complement receptors.

Monocyte complement receptors (MCR) and enhancement of MCR by a monocyte chemotactic factor (casein) (CRE) were measured in corticosteroid-resistant and corticosteroid-responsive chronic asthmatics. In newly-diagnosed patients who subsequently responded to corticosteroids, the percentage of MCR and CRE was lower after taking oral prednisolone for 7 days and returned to pretreatment values when prednisolone was withdrawn. MCR and CRE in corticosteroid-responsive asthmatics receiving prednisolone were significantly lower than in corticosteroid-resistant asthmatics taking prednisolone. However, there was no significant difference in MCR and CRE between non-responders taking prednisolone and non-responders receiving other forms of therapy. These results suggest that one of the effects of systemic corticosteroids in asthmatics who respond to this form of treatment is a decrease in both MCR and the degree of CRE. Since these changes were not found in corticosteroid-resistant chronic asthmatics such patients may have a defect in the expression and mobilization of complement receptors on the monocyte cell membrane.     

Effects of prednisolone on eosinophils, IL-5, eosinophil cationic protein, EG2+ eosinophils, and nitric oxide metabolites in the sputum of patients with exacerbated asthma

Corticosteroids are considered to be one of the most effective medicine for asthma by suppressing airway inflammation. This study was carried out to investigate the effects of prednisolone in the sputum of exacerbated asthmatics. Clinical severity, cell differentials, levels of interleukin (IL)-5, eosinophil cationic protein (ECP), EG2+ eosinophils, and nitric oxide (NO) metabolites were measured. Sputum was examined 2 weeks apart in 13 exacerbated asthmatics before and after prednisolone treatment, and once in 12 stable asthmatics. We used a sandwich ELISA for IL-5, fluoroimmunoassay for ECP, immunohistochemical staining for EG2+ eosinophils, a NO metabolites assay using modified Griess reaction. Exacerbated asthmatics, in comparison with stable asthmatics, had significantly higher proportion of eosinophils, higher level of ECP, higher percentage of EG2+ eosinophils, and NO metabolites. Exacerbated asthmatics after treatment with prednisolone had reduced the proportions of eosinophils, reduced level of IL-5, ECP and percentage of EG2+ eosinophils. FEV1 was correlated with the proportion of eosinophils, ECP, and IL-5 respectively. These findings suggest that prednisolone is considered to be effective medicine for asthma by suppressing eosinophil activation through IL-5.     

Methotrexate therapy of oral corticosteroid-dependent asthmatics reduces serum immunoglobulins: correlation with clinical response to therapy

BACKGROUND: Concomitant methotrexate (MTX) therapy of oral corticosteroid (CS)-dependent asthmatics has been shown to spare CS therapy, but the mechanism is unknown. In a previous report, we showed that MTX increases T cell inhibition by CS. In this report we focus on effects of MTX on immunoglobulin concentrations and their possible clinical relevance. OBJECTIVE: To monitor changes in circulating leucocytes and Ig in a group of these patients during MTX therapy, and to relate these changes to clinical 'response' as defined by oral CS reduction. METHODS: Sixteen severe asthmatics dependent on oral prednisolone 15 (7.5-25) mg/day in addition to high dose inhaled CS were treated with MTX 15 mg intramuscularly, weekly for 28 weeks. Prednisolone dosages were maintained constant for 12 weeks then reduced systematically over the next 16 weeks provided that asthma control did not deteriorate. Patients were classified a priori as 'responders' or 'non-responders' to MTX (reduction of initial oral prednisolone requirement by >or=50% or <50%, respectively). Patients were followed-up for a further 12 weeks after MTX withdrawal. Serum Ig and differential blood leucocyte counts were measured at baseline, 12, 28 and 40 weeks. RESULTS: MTX therapy allowed significant, but individually variable, reductions in oral prednisolone dosages (P<0.00001) without alteration of lung function or symptoms. This was associated with significant reductions in mean serum concentrations of Ig of all classes, which reversed following MTX withdrawal. Reductions in IgE and IgG were significantly greater in the MTX 'responders' as compared with 'non-responders', and changes in IgE, IgG and IgM correlated with changes in prednisolone requirements. Differential blood leucocyte counts showed no significant variation. CONCLUSION: MTX therapy reduced oral CS requirements in these severe asthmatics to a degree which correlated with reduced circulating Ig but not lymphopaenia, suggesting a possible cause and effect relationship. These reductions might also contribute to the documented incidence of opportunistic infection in these circumstances.     

Hypogammaglobulinemia in steroid-dependent asthmatics correlates with the daily dose of oral prednisolone

BACKGROUND: Steroid-induced adverse effects including suppression of humoral immunity should be considered in steroid-dependent severe asthma. Only a few studies have determined the exact steroid dose that could potentially suppress humoral immunity in asthmatics. METHODS: Randomly selected 100 adult asthmatics treated with inhaled beclomethasone dipropionate (BDP) were classified into three groups based on the dose of steroid to determine the serum IgG, IgA and IgM levels by radioimmunoassay. Relationships between serum immunoglobulin levels and the daily dose and duration of oral prednisolone (PSL) therapy were examined. RESULTS: None of the patients on inhaled corticosteroid alone had hypogammaglobulinemia. Patients on oral PSL at a dose >12.5 mg/day for at least 1 year had low serum IgG. There was no significant correlation between the duration of oral PSL therapy and serum IgG. CONCLUSIONS: Oral PSL can potentially suppress humoral immunity in severe asthma. In asthmatics, hypogammaglobulinemia could develop in those on a daily dose of PSL >12.5 mg, but is independent of the duration of such treatment. No suppression of humoral immunity was noted on inhaled corticosteroid therapy alone, either at low or high dose.     

Are the asthma guideline goals achieved in daily practice? A population-based study on treatment adequacy and the control of asthma

BACKGROUND: The guidelines for asthma recommend that the use of anti-inflammatory therapy should be adapted to the severity of the disease. However, few data are available to assess the adequacy of the use of drugs and its influence on the control of asthma in 'real life'. METHODS: The adequacy of the current use of anti-asthmatic medication according to the Global Initiative for Asthma (GINA) guidelines was assessed in a random sample of 400 asthmatics identified in the frame of the Italian Study on Asthma in Young Adults. Asthma severity was assessed using the GINA criteria; accordingly, a patient was classified as receiving inadequate treatment if his/her current use of drugs was lower than that suggested by the guidelines for the corresponding severity level. The absence of asthma attacks in the last 3 months was used as an indicator of the disease control. RESULTS: Fifty-five percent of the patients had persistent asthma. Overall, 48% (95% CI 41.2-54.8) of persistent asthmatics were receiving inadequate treatment, and 66% (95% CI 59.5-72.4) had not used their medication daily over the past 3 months. Persistent asthmatics who were inadequately treated had a significantly greater frequency of asthma attacks (geometric mean ratio 3.7; 95% CI 2.1-6.6) than those using an adequate dose of medication. Mild and moderate persistent asthmatics using an adequate medication regimen reported a low number of asthma attacks (median 0). At the multivariate analysis, a good control of the disease was positively associated with an adequate dose of anti-inflammatory medication (OR = 2.2; 95% CI 1.1-4.5) and was negatively associated with a later onset of asthma (OR = 0.96; 95% CI 0.93-0.99) and severe asthma (OR = 0.37; 95% CI 0.17-0.81). CONCLUSIONS: Despite the increase in the use of inhaled corticosteroids, half of the persistent asthmatics from the general population are using a medication regimen below their severity level. When the use of drugs follows the GINA guideline recommendations, a good control of asthma is also achievable in the daily management of the disease, particularly in the case of mild and moderate asthmatics.     

Corticosteroid resistance in mild asthma: markers of persistent inflammation.

BACKGROUND: Bronchial hyperresponsiveness (BHR) is an important feature of asthma. Glucocorticosteroids (GCS) reduce BHR, probably by suppressing allergic inflammation. There are, however, two groups of asthmatics with either GCS-responsive or non-responsive BHR to methacholine. We investigated the mechanism of non-GCS-responsive BHR in mild asthma. METHODS: Non-GCS-responsive BHR asthma was defined as failure of reduction of BHR to methacholine after a 2-week course of oral prednisolone (30 mg/day). The expression of interleukin (IL)-4, IL-5, IFN-gamma mRNA in peripheral blood mononuclear cells, eosinophil count, serum cortisol, eosinophilic cationic protein (ECP), and spirometry were measured in five non-GCS-responsive BHR asthmatics and six patients with GCS-responsive BHR asthma before and after prednisolone therapy. RESULTS: With the exception of serum ECP and expression of IL-5 mRNA, no significant differences were observed between GCS-responsive BHR and non-GCS-responsive BHR asthma. The mean ECP level was significantly higher in non-GCS-responsive BHR than in GCS-responsive BHR asthma before and after prednisolone therapy. Interleukin-5 mRNA was detected in all asthmatics before prednisolone therapy; however, after prednisolone therapy, IL-5 mRNA was only detected in non-GCS-responsive BHR asthmatics. CONCLUSIONS: Our findings suggest that activation of eosinophils appears to persist in some asthmatics with non-GCS-responsive BHR due to continuous IL-5 production by lymphocytes.     

Sodium cromoglycate nebulized solution has an acute bronchodilative effect in patients with aspirin-intolerant asthma (AIA)]

Sodium cromoglycate (SCG) (Intal) is a well-known anti-allergic agent which protects against allergen- and exercise-induced bronchospasms. The effect has been recognized non-acute, unlike that of bronchodilators. However, we have found that some patients with aspirin-intolerant asthma (AIA) show significant improvement soon after a single inhalation of SCG nebulized solution. In this study, we investigated the acute bronchodilator effect of SCG given by nebulizer in adult asthmatics, especially compairing AIA with non-AIA (aspirin-tolerant asthma) patients. Twenty patients with AIA and 11 with non-AIA participated in the study. After performing spirometry on remission, they inhaled either SCG via a nebulizer or 4 ml of placebo in a randomized double-blind fashion. After inhalation, spirometry was performed every ten minutes for one hour. The placebo used was a saline solution of the same osmolarity as that of the SCG nebulized solution. Placebo inhalation provoked asthmatic attacks in five of the patients with AIA and one with non-AIA, but SCG did not. In the AIA group, twelve out of the twenty patients also had improved nasal symptoms soon after inhalation of SCG. Forced expiratory volume in one second (FEV1) was significantly improved 10 minutes after inhalation of SCG. Fifty minutes after SCG inhalation, the percent degree of FEV1 improvement was approximately 17%. However, FEV1 was significantly decreased by approximately 14% after inhalation of placebo. In the non-AIA group, FEV1 was not increased after inhalation of SCG. V25 was not changed after inhalation of SCG in AIA and non-AIA groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Lost to Follow-Up in Asthmatics Does Not Mean Treatment Failure: Causes and Clinical Outcomes of Non-Adherence To Outpatient Treatment In Adult Asthma

Purpose

Long-term asthma management is recommended to asthmatics; however, many patients do not adhere to follow-up treatment. It is unclear why many asthmatics do not adhere to follow-up treatment and long-term clinical course after discontinuation of asthma management. This study investigates the factors associated with loss to follow-up and observes the clinical course in asthmatics who discontinued asthma treatment.

Methods

A retrospective investigation was conducted after reviewing medical records of adult patients who were newly diagnosed with asthma at a university hospital in Seoul, South Korea from January 2005 to March 2007. We compared baseline demographics and the clinical and laboratory profiles of patients to see if they successfully adhered to the treatment at an outpatient clinic for at least 3 years. The clinical course and asthma control status were surveyed by telephone for patients who were lost to follow-up within 3 years.

Results

A total of 351 (73.9%) out of 475 patients were lost to follow-up within 3 years of asthma diagnosis. Patients lost to follow-up were younger and had clinical features of less severe asthma at time of diagnosis (higher FEV1 and PC20, and lower grade treatments) compared to patients who adhered to the follow-up for longer than 3 years (all P<0.05). Among the 198 responders to the telephone survey, 124 responders (62.6%) answered that they eventually discontinued asthma medication. A significantly higher proportion of the 124 responders who discontinued asthma treatment maintained symptom improvement compared to the 74 responders who continued asthma medication (77.4% vs. 55.4%, P=0.003).

Conclusions

Almost three quarters of newly diagnosed asthmatics discontinued asthma medication within 3 years despite a medical recommendation. There are considerable numbers of asthmatics who can maintain long-term asthma control status without medication.     

Inhibition of methylprednisolone elimination in the presence of clarithromycin therapy

BACKGROUND: Macrolide antibiotics have long been used as steroid-sparing agents in patients with severe steroid-dependent asthma. Their efficacy and their propensity to potentiate glucocorticoid adverse effects have been attributed in part to their ability to delay glucocorticoid clearance. OBJECTIVE: We sought to determine whether clarithromycin, a newer macrolide antibiotic, can alter the pharmacokinetic profile of oral glucocorticoids and thereby increase the risk of steroid-induced adverse effects. METHODS: An open-label study in a paired design (before and after treatment) was conducted in a hospital-based outpatient clinic. Participants were 6 adult patients (mean age, 30 years) with mild-to-moderate asthma. Prednisone (40 mg/1.73 m2) and methylprednisolone (40 mg/1.73 m2) were given as single randomized doses on consecutive study days before and on days 8 and 9 of a clarithromycin (500 mg twice daily) course. Twelve-hour pharmacokinetic profiles with measurement of plasma methylprednisolone and prednisolone levels were taken before and after clarithromycin therapy. RESULTS: Clarithromycin therapy resulted in a 65% reduction of methylprednisolone clearance and significantly higher mean plasma methylprednisolone concentrations compared with preclarithromycin concentrations but had no significant effect on prednisolone clearance or mean prednisolone plasma concentrations. CONCLUSIONS: Clinicians must be aware of potential drug interactions that could place patients at increased risk for steroid-induced adverse effects. Such an effect has been demonstrated between clarithromycin and methylprednisolone, two drugs that may be administered concomitantly in asthma. To avoid potential steroid-enhancing effects, prednisone should be substituted for methylprednisolone during prolonged courses of clarithromycin therapy.     

Relation between exhaled carbon monoxide levels and clinical severity of asthma

Carbon monoxide (CO) can be detected in exhaled air and is increased in asthmatic patients not treated with corticosteroids. However, it is uncertain whether exhaled CO is related to severity of asthma. To study whether exhaled CO is related to severity of asthma in clinical courses, exhaled CO concentrations were measured on a CO monitor by vital capacity manoeuvre in 20 mild asthmatics treated with inhaled beta2-agonists alone, 20 moderate asthmatics treated with inhaled corticosteroids, and 15 stable asthmatics treated with high dose inhaled corticosteroids and oral corticosteroids once a month over 1 years. Exhaled CO concentrations were also measured in 16 unstable severe asthmatics who visited the hospital every 7 or 14 days for treatment with high dose inhaled corticosteroids and oral corticosteroids. The mean values of exhaled CO in severe asthma over 1 year were 6.7 +/- 9.5 p.p.m. (n = 31, mean +/- SD) and significantly higher than those of non-smoking control subjects (1.2 +/- 0.9 p.p.m., n = 20, P < 0.01). Exhaled CO concentrations in unstable severe asthmatics were significantly higher than those in stable severe asthmatics. However, exhaled CO concentrations in mild and moderate asthmatics did not differ significantly from those in non-smoking control subjects (P > 0.20). There was a significant relationship between the exhaled CO concentrations and forced expiratory volume in one second in all asthmatic patients. These findings suggest that exhaled CO concentrations may relate to the severity of asthma and measurements of exhaled CO concentrations may be a useful means of monitoring airway inflammation in asthma.     

Effect of single dose of prednisolone on hospitalisation in patients of acute bronchial asthma

The present study was undertaken to assess the effect of stat dose of oral prednisolone on rate of hospitalisation in patients of acute bronchial asthma. 259 patients, aged 1-65 years presenting with acute exacerbation of asthma were randomised in a double blind fashion to receive a stat dose of oral prednisolonev (30 mg if age < 5 years; 60 mg if age > 5 years) or equivalent placebo. Then, nebulbutamol (0.15 mg/kg in 2 m/l normal saline) was given to all patients and patients were re-examined after 4 hours to decide about the hospitalisation. The study revealed that only 37 (26.42%) patients required hospitalisation and further management in prednisolone group compared to 50 (42.01%) patients in placebo group (p < 0.01). This suggests that prompt use of single oral dose of prednisolone along with routine bronchodilator therapy can significantly reduce morbidity and need for hospital admission in patients of acute bronchial asthma.     

Toll-like Receptor Expression on Peripheral Blood Mononuclear Cells in Asthmatics; Implications for Asthma Management

Background

Accumulating evidence indicates that cells expressing Toll-like receptors (TLRs) play an important role in allergic diseases. The authors undertook this study to explore the hypothesis that TLR-mediated inflammatory signals are important from the perspective of asthma management.

Methods

The expressions of TLR1, TLR2, TLR3, TLR4, TLR6, and TLR9 and levels of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8, and IFN-γ) on the peripheral blood mononuclear cells (PBMCs) of 36 stable asthmatics on treatment (the on-treatment group), 15 asthmatics (the treatment-naïve group) before and after a 7-day course of oral prednisolone (30 mg/day), and on the PBMCs of 15 healthy controls were measured after in vitro stimulation using TLR-specific ligands.

Results

In the on-treatment group, TLR1, TLR2, TLR6, and TLR9 expressions on PBMCs were significantly different between asthmatics and controls. And the expression of TLR4 on PBMCs and TNF-α production stimulated by lipopolysaccharide (LPS), were significantly higher in mild to moderate than in severe asthmatics. Interestingly, in the treatment-naïve group, short-term prednisolone significantly increased LPS-induced TNF-α and IFN-γ productions by PBMCs.

Conclusion

TLR-mediated inflammatory signals contribute to the development and severity of asthma and are not reduced by glucocorticoid treatment, which suggests that a TLR-specific antagonist and glucocorticoid are required for the effective control of airway inflammation in asthmatics.