Glucocorticosteroids attenuate aspirin-precipitated adverse reactions in aspirin-intolerant patients with asthma

We evaluated the effects of corticosteroid pretreatment on the intensity of adverse reactions to aspirin during carefully controlled aspirin challenges in 13 aspirin-sensitive asthmatics. Two studies were performed. First, using a double-blind crossover design, we administered to five patients 75 mg prednisone daily or placebo for two days preceding the challenge. No consistent protection against adverse reactions was achieved. In the second study, a 10-day pretreatment with 15 mg oral prednisolone and topical intrabronchial and intranasal beclomethasone offered total clinical protection against bronchospasm produced by threshold doses of aspirin in five of eight patients. In two others, the bronchospasm provoked was less severe, and only in one patient did its intensity remained unchanged. There was a significant reduction in fall of mean pulmonary function tests following the second aspirin challenge, which was performed after ten days of steroid treatment. Steroids given for ten days also prevented significantly nasal discharge and nasal blockade. When diagnostic challenge tests with aspirin are carried out in asthmatic patients on long-term corticosteroid therapy, there is an increased possibility of false negative results.

Effects of inhibition of thromboxane A2 synthesis in aspirin-induced asthma

Since inhibition of cyclooxygenase precipitates asthmatic attacks in patients with aspirin idiosyncrasy, we have evaluated the effects of pharmacologic inhibition of thromboxane A2 (TXA2) synthetase, next to cyclooxygenase enzyme in arachidonic acid cascade. Sixteen patients with aspirin-induced asthma received increasing doses on 3 days (25 to 400 mg) of an imidazole derivative, OKY-046, which specifically blocks TXA2 synthetase. Twenty-three healthy control subjects received a single dose of 400 mg of OKY-046. In both patients and control subjects, the inhibitor at a dose of 400 mg produced (1) a pronounced fall in thromboxane B2 serum levels, (2) a rise in serum 6-keto-prostaglandin F1 alpha, and (3) a depression in platelet aggregability to arachidonic acid and adenosine diphosphate. The drug, however, neither precipitated attacks of asthma nor impaired pulmonary function tests throughout a 24-hour observation period. Five patients, but none of the control subjects, developed transient nasal congestion about 1 hour after taking the drug. Thus, inhibition of TXA2 synthetase, contrary to inhibition of cyclooxygenase, does not affect bronchopulmonary function in patients with asthma and aspirin intolerance.

The effect of prostacyclin on asthma precipitated by aspirin

Inhibition of prostacyclin biosynthesis by aspirin might be expected to promote asthmatic attacks in aspirin-intolerant patients. In vitro, prostacyclin inhibits generation of leukotrienes and opposes their bronchoconstrictive action. In a double-blind study we compared the effects of intravenous infusions of prostacyclin with those of its solvent on bronchoconstriction provoked by threshold doses of aspirin in 9 known aspirin-sensitive asthmatics. The intensity of bronchial obstruction precipitated by aspirin was similar during prostacyclin and placebo infusions. There was no difference in other symptoms of intolerance, except for rhinorrhea which seemed accentuated by prostacyclin (possibly because of nasal vasodilatation). Our results suggest that either the inhibitory effects of prostacyclin on leukotrienes described in vitro do not apply in vivo, or the importance of leukotrienes have been overestimated in this type of asthma. Idiosyncrasy to aspirin, which affects 5-10% of adult asthmatics, was thought several decades to be of allergic background, while in fact numerous and extensive immunological studies ruled out typical IgE--mediated allergic mechanisms for aspirin--induced asthma. In 1974, at the Department of Allergy and Clinical Immunology in Cracow, a novel hypothesis was put forward. If stated that in sensitive patients, precipitation of asthmatic attacks by aspirin and by certain nonsteroidal antiinflammatory drugs (NSAID) results from inhibition of specific enzyme in the bronchi, cyclooxygenase, leading to an imbalance of prostanoids in the respiratory tract. Over the years which followed evidence has been accumulated which strongly support this hypothesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Bleeding time and PAF-acether-induced platelet aggregation in atopy

In a double-blind cross-over study 20 mg of aspirin or placebo were administered to 18 patients with respiratory atopy without eczema and to 12 healthy controls. Mean bleeding time before administration of either aspirin or placebo was on average about 1 min. longer in atopics than in the controls, and this difference was significant (p 0.05). Atopics' platelets also aggregated less well in response to arachidonic acid in comparison to controls. On the contrary, no difference in platelet aggregability was detected in response to either PAF-acether alone or to combination of subthreshold, synergistic concentrations of PAF-acether and collagen. Aspirin at a dose used did not affect either bleeding time or platelet aggregability. Thus, in respiratory atopy there exists a moderate hemostatic imbalance, the reason of which remains to be established.

Lack of effect of i.v. prostacyclin on aspirin-induced asthma

Inhibition of prostacyclin biosynthesis by aspirin might be expected to promote asthmatic attacks in aspirin-intolerant patients. In vitro, prostacyclin impedes generation of leukotrienes and opposes their bronchoconstrictive action. In a double-blind study we compared the effects of intravenous infusions of prostacyclin with those of its solvent on bronchoconstriction provoked by threshold doses of aspirin in nine known aspirin-sensitive asthmatics. The intensity of bronchial obstruction precipitated by aspirin was similar during prostacyclin and placebo infusions. There was no difference in other symptoms of intolerance, except for rhinorrhea which seemed accentuated by prostacyclin (possibly because of nasal vasodilatation). Our results suggest that either the inhibitory effects of prostacyclin on leukotrienes described in vitro do not apply in vivo, or the importance of leukotrienes has been overestimated in this type of asthma.

Aspirin sensitive asthma and arachidonic acid transformation

Inhibition by nonsteroidal antiinflammatory drugs of cyclooxygenase appears to be the basic mechanism operating in aspirin-sensitive asthma. Evidence in favor of this theory is presented. We also discuss biochemical consequences of blockade of cyclooxygenase for clinical symptomatology, prevention and treatment of aspirin-sensitive asthma.

Hydrocortisone and airflow impairment in aspirin-induced asthma

We studied the effects of intravenous injection of hydrocortisone, as compared to its solvent, in 31 patients with aspirin-induced asthma. Mean FEV1 fell significantly 5 minutes after an intravenous bolus of 300 mg of hydrocortisone, but not after the solvent, and returned to the initial values 1 hour later. Only three of 31 patients displayed at this time clinical signs of increased impairment of airflow that resolved spontaneously. Neither in these three patients nor in another patient known already to respond with bronchoconstriction to 30 to 50 mg of hydrocortisone did intravenous injections of 20 mg of methylprednisolone, 4 mg of dexamethasone, or 4 mg of betamethasone produce any signs of bronchial obstruction. In the whole group of patients, mean FEV1 increased significantly 3 to 5 hours after hydrocortisone injection. It is hypothesized that hydrocortisone might induce early bronchoconstriction in patients with aspirin-induced asthma through its inhibitory effects on prostanoid biosynthesis. Use of intravenous steroids other than hydrocortisone is advisable in patients with aspirin-induced asthma.

Bronchodilatory properties of 2-decarboxy-2-hydroxymethyl prostaglandin E1

We evaluated in a double-blind study the bronchodilatory properties of 2-decarboxy-2-hydroxymethyl prostaglandin E1 (PGE1-carbinol), described recently as a nonirritant bronchodilator in animals. Fifteen asthmatic patients received by inhalation single doses of 1, 10, and 30 micrograms PGE1-carbinol, 55 micrograms PGE2, and placebo (10% ethanol in normal saline, which was also used as diluent for the PGs). Such pulmonary function tests as forced expiratory volume in 1 second, forced vital capacity, and maximal expiratory flow were monitored during 2 hours following inhalation of each compound. 10 and 30 micrograms PGE1-carbinol produced significant but short-acting bronchodilation, similar to that caused by 55 micrograms PGE2. One-third of the patients reported mild cough and throat irritation during and shortly after inhalation of 30 micrograms PGE1-carbinol or 55 micrograms PGE2. Placebo and 1 microgram PGE1-carbinol produced minimal side effects, but neither agent caused bronchodilation. In an adjunctive, unblinded trial, the same patients received 400 micrograms fenoterol. Fenoterol caused greater bronchodilation 15 and 30 minutes after inhalation than did the PGs in the double-blind study.

Adverse reactions to suxamethonium and other muscle relaxants under general anesthesia

The mechanisms of anaphylactic reactions to muscle relaxants under general anesthesia are not completely understood. Extending an earlier study, we report 41 cases of anaphylactic shock investigated by intradermal skin tests with muscle relaxants (suxamethonium, pancuronium, gallamine, nortoxiferine), in vitro leukocyte histamine release, and Prausnitz-Küstner tests. Intradermal tests were significantly positive at concentrations ranging from 10 to 10(5) times less than those in controls. Reproducibility tested for suxamethonium at a 1-year interval in five patients was good. Histamine release induced by muscle relaxants in Tris-albumin-Ca++-Mg++ buffer showed positive results in 8/25 instances and was inhibited by antigen excess in seven cases. Addition of 50% deuterium oxide (D2O) caused significant increase of histamine release in positive cases and induced release in all five negative cases studied. Muscle relaxant-induced histamine release was inhibited by in vitro anti-IgE leukocyte desensitization. The mean maximal histamine release dropped from 58.2% +/- 9.7 to 5.8% +/- 2 (p less than 0.01). Similarly, leukocyte desensitization also inhibited histamine release induced by anti-IgE but not by formyl-L-methionyl-L-leucyl-L-phenylalanine or poly-L-arginine. Prausnitz-Küstner tests were positive in five out of 21 cases studied and became negative after heat inactivation. These results confirm the usefulness of intradermal skin tests in diagnosis of patients' reaction to muscle relaxants and suggest an IgE-mediated rather than an idiosyncratic mechanism.

Asthma improved by aspirin-like drugs

In six adult patients with bronchial asthma aspirin in a single dose of 0.3-1.2 g produced bronchodilatation with a marked improvement in both clinical symptoms and pulmonary function tests. In these patients asthma was characterized by the following traits: onset after a flu-like infection, perennial course, lack of relation to specific allergenic exposures, negative skin tests with common aeroallergens, and history of rhinorrhoea or sinusitis. Oral challenge with 12 nonsteroidal anti-inflammatory drugs performed in two patients showed that bronchodilatation could be induced not only by aspirin but also by other drugs which inhibit cyclo-oxygenase. This response to aspirin is rare and proper diagnosis is of vital importance, since the same aspirin-like drugs which proved effective in these patients may provoke dangerous bronchoconstriction in other clinically indistinguishable patients with asthma.

Bronchial reactivity to prostaglandins F2alpha, E2, and histamine in different types of asthma

Bronchial reactivity to prostaglandins F2alpha (PGF2alpha), E2 (PGE2) and histamine has been studied in 27 patients with aspirin-sensitive asthma and in 28 asthmatics without this sensitivity. Of the latter group, 13 patients had atopic, 9 infectious, and 6 mixed type of asthma. Atopic patients were characterized by vivid reactivity to low doses of both PGF2alpha and histamine. In patients with infectious asthma significantly higher doses of both PGF2alpha and histamine were necessary to induce bronchoconstriction as compared to atopics. Aspirin-sensitive patients responded quickly with bronchial spasm to similar doses of histamine as atopics, but tolerated significantly higher doses of PGF2alpha. There was no difference in reactivity to PGF2alpha between patients with aspirin sensitivity and those with infectious asthma. 5 and 10 min after administration of 60 microgram PGE2 significantly better improvement in ventilation occurred in aspirin-sensitive patients than in those of either atopic or infectious groups. The results obtained point to differences in bronchial reactivity to prostaglandins and histamine depending on type of asthma and severity of its symptoms.