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Joaquín Sastre

Publications and source records attributed to Joaquín Sastre.

15 recordsLinked to original sources
PubMed2006

Occupational asthma due to chromium and nickel salts.

BACKGROUND: Exposure to chromium and nickel salts is a poorly characterized cause of occupational asthma. METHODS: We describe four patients with work-related asthma due to metallic salts. Skin-prick tests to potassium dichromate and nickel sulfate were performed. The patients underwent methacholine inhalation tests and specific inhalation challenges (SIC) with both chromium and nickel salts. RESULTS: Two patients showed positive skin-prick tests to potassium dichromate and nickel sulfate. All patients had bronchial hyperresponsiveness to methacholine, which increased 24 h after SIC with metallic salts. SIC with potassium dichromate elicited late asthmatic reactions (LAR) in two workers, one subject had an early asthmatic reaction (EAR), and another subject showed a dual asthmatic reaction (DAR). SIC with nickel sulfate induced a DAR in one subject and a late asthmatic reaction in another. CONCLUSIONS: Chromium and nickel salts can give rise to occupational asthma in exposed workers. The underlying mechanism may be IgE-mediated in some cases.

Adult↗
PubMed2006

Hypersensitivity to black locust (Robinia pseudoacacia) pollen: "allergy mirages".

BACKGROUND: The allergenicity of the ornamental tree Robinia pseudoacacia, or black locust, is unknown. OBJECTIVE: To evaluate the prevalence of sensitization to R. pseudoacacia pollen, its possible allergenic cross-reactivity with other common pollens, and the potential implication of pollen panallergens (profilin, polcalcin, and 1,3-beta-glucanase) as a cause of sensitization to R. pseudoacacia pollen. METHODS: Skin prick testing with R. pseudoacacia pollen was performed in 149 patients with pollinosis. Nasal challenge with R. pseudoacacia pollen was performed in 10 patients. The prevalence of sensitization to the recombinant forms of profilin (rChe a 2), polcalcin (rChe a 3), and the N-terminal of the 1,3-beta-glucanase (rNtD of Ole e 9) was investigated. Immunoblotting, enzyme-linked immunosorbent assay, and competitive inhibition assays were performed with R. pseudoacacia pollen and recombinant pollen allergens. RESULTS: Sixty-four patients (43%) had positive skin prick test reactions to R. pseudoacacia pollen. Nasal challenge results were positive in 5 sensitized patients and negative in 4 controls and 1 sensitized patient. The allergenic profile of R. pseudoacacia pollen comprises at least the panallergen profilin, a calcium-binding protein, and a 1,3-beta-glucanase. The prevalence of sensitization to rChe a 2, rChe a 3, and rNtD of Ole e 9 was 60%, 33%, and 87%, respectively, among patients sensitized to R. pseudoacacia pollen. Binding of IgE to R. pseudoacacia extract was completely inhibited by Robinia, Chenopodium, Olea, Cupressus, and Lolium extracts. CONCLUSIONS: The high prevalence of R. pseudoacacia pollen sensitization in patients with pollinosis is likely to be due to cross-sensitization to panallergens (profilin, polcalcin, and 1,3-beta-glucanase) from other common pollens. This phenomenon may lead to a diagnosis of "allergy mirages."

Allergens↗
PubMed2006

Immunotherapy: an option in the management of occupational asthma?

PURPOSE OF REVIEW: To review clinical data on immunotherapy applied to occupational asthma. RECENT FINDINGS: There are very few studies on immunotherapy in occupational asthma. The best documented use of immunotherapy in this disorder corresponds to latex allergy among healthcare workers. There are anecdotic reports of non-well controlled studies using immunotherapy with wheat flour, African maple wood, sea squirt and rat epithelium extracts. Subcutaneous immunotherapy with natural rubber latex extract, at adequate doses, seems to be a useful treatment in reducing cutaneous and respiratory symptoms, but it should be considered as a high-risk treatment due to the appearance of systemic reactions. SUMMARY: At present, subcutaneous immunotherapy with latex extract can only be considered experimental and must be administered by experienced allergists in a hospital setting, similarly to venom immunotherapy. Nevertheless, systemic reactions responded well to treatment. Further clinical trials on efficacy, safety and long-term effectiveness in immunoglobulin E-mediated occupational rhinitis and asthma are clearly needed. Since allergen avoidance is not always possible, no other etiologic treatment but immunotherapy can be offered to patients with occupational rhinitis/asthma.

Animals↗
PubMed2004

[Occupational asthma].

Occupation Asthma is defined as an illness characterized by the existence of a variable limitation of one's air flow or a bronchial hyper-reactivity due to causes and conditions attributed to a determined labor medium and not to stimuli found outside one's work place. We can distinguish two main types of occupational asthma, based on the most likely mechanism involved in causing it: an immune type asthma which has a latent period and includes all those cases which have a proven or probable immune mechanism; and a non-immune type which is manifested by a reactive dysfunction in the respiratory channels syndrome, or in other words, by asthma induced by irritating agents.

Asthma↗
PubMed2003

Specific immunotherapy with a standardized latex extract in allergic workers: a double-blind, placebo-controlled study.

BACKGROUND: Preventive measures have been proposed to reduce the risk of sensitization to natural rubber latex (NRL), but this is not always feasible. OBJECTIVE: The aim of this study was to determine the efficacy and safety of specific immunotherapy with a standardized latex extract in sensitized workers. METHODS: Twenty-four patients allergic to NRL with contact urticaria (n = 8) and rhinitis or asthma (n = 16) were included (16 in the active group and 8 in the placebo group). Treatment started in a cluster immunotherapy protocol, with injections every week for 3 months and then every other week for another 3 months. RESULTS: Patients in the active group had significantly lower values than patients in the placebo group in skin terms of reactivity to NRL (P <.01), rubbing test results (P =.047), and latex glove use test results (P =.046) after 6 months of treatment. There were no significant differences between the active and placebo groups in symptom scores, use of medication, self-assessment, or methacholine test results either before or after treatment. Differences in nasal and bronchial symptoms during specific inhalation challenges (P = not significant and P =.05, respectively) were observed in favor of the active group. In the active group 32 systemic reactions were observed (8% of doses), mostly during the build-up period, being more frequent in patients with respiratory symptoms (P =.004). All reactions responded promptly to treatment. CONCLUSION: Clinical efficacy was shown mainly on cutaneous symptoms, although an improvement in rhinitis and asthma symptoms was also observed during specific inhalation challenges. Latex-specific immunotherapy might be a useful approach for the treatment of latex allergy in sensitized workers.

Adult↗
PubMed2003

Quantified environmental challenge with absorbable dusting powder aerosol from natural rubber latex gloves.

BACKGROUND: There are few data that link quantified natural rubber latex (NRL) absorbable dusting powder aerosol to biologic responses in NRL-sensitized subjects. METHODS: We conducted a study on 30 health care workers with possible occupational asthma. All the subjects but 2 had a positive skin prick test result with NRL extract. Quantified environmental challenge (QEC) with powdered NRL gloves was performed in a 7-m(3) chamber. The patients would don and discard a pair of gloves every 3 minutes up to a maximum of 60 minutes. The concentrations of NRL aeroallergen were measured by a competitive IgE immunoassay. Ocular and respiratory symptoms and pulmonary function were monitored. RESULTS: Twenty-six patients (87%) had rhinoconjunctivitis, 19 (63%) had an asthmatic response (responders), and 1 patient developed eosinophilic bronchitis on QEC. The asthmatic responses were of the early type in 15 patients, dual in 3, and isolated late in 1 patient. The duration of exposures sufficient to elicit asthmatic responses varied from 3 to 114 cumulative minutes. Time-weighted average NRL aeroallergen concentrations during QEC with responders ranged between 199 and 1107 ng/m(3). NRL concentrations measured at various time points during exposure were reproducible. Measured concentrations of NRL aeroallergen between responders (677 +/- 281 ng/m(3)) and nonresponders (611 +/- 351 ng/m(3)) were not statistically different. The cumulative inhaled NRL aeroallergen dose required for an asthmatic response ranged between 25 to 515 ng. CONCLUSION: The total dose of latex aeroallergen eliciting an asthmatic response during QEC was mostly affected by the duration of exposure and varied widely from person to person.

Adult↗
PubMed2003

Need for monitoring nonspecific bronchial hyperresponsiveness before and after isocyanate inhalation challenge.

BACKGROUND: Specific and nonspecific bronchial responsiveness may decline or disappear after cessation of exposure in the workplace in patients with occupational asthma, leading to false-negative specific inhalation challenge (SIC) results. METHODS: Twenty-two patients with suspected diisocyanate-induced asthma were studied. SIC with diisocyanates (toluene diisocyanate [TDI] or hexamethylene diisocyanate [HDI]) was carried out in a 7-m(3) dynamic chamber up to a maximum concentration of 19 parts per billion for 120 min. Methacholine inhalation challenges were performed before and 24 h after SIC with TDI or HDI. Patients who did not show an asthmatic reaction after SIC but had a greater than twofold reduction in provocative concentration of methacholine causing a 20% fall in FEV(1) (PC(20)) after the first isocyanate challenge underwent a second isocyanate SIC 2 days later. RESULTS: The first SIC with isocyanates elicited an asthmatic reaction in 13 patients (59%). In five patients who did not show an asthmatic reaction after the first SIC, PC(20) exhibited more than a twofold reduction. In three of the five patients, a second SIC with isocyanates elicited an immediate positive asthmatic reaction. Therefore, 3 of 16 patients (19%) were ultimately shown to have bronchial responsiveness to isocyanate; occupational asthma was demonstrated due to post-SIC monitoring of bronchial hyperresponsiveness to methacholine. CONCLUSION: PC(20) should be systematically assessed before and after SIC with isocyanates in the absence of significant changes in FEV(1) during SIC to avoid false-negative results.

Adult↗
PubMed2002

Glucoamylase: another fungal enzyme associated with baker's asthma.

BACKGROUND: Aspergillus-derived enzymes are widely used as dough additives in the baking industry. These enzymes may give rise to immunoglobulin (Ig)E-mediated sensitization and occupational asthma. Glucoamylase (or amyloglucosidase) is an important industrial enzyme obtained from Aspergillus niger and used to provide fermentable sugars for yeast to improve loaf volume and texture. OBJECTIVE: The aim of our study was to investigate the potential allergenic role of glucoamylase in baker's asthma. METHODS: We report four subjects with work-related allergic respiratory symptoms who were exposed to glucoamylase and other starch-cleaving enzymes used as baking additives. The causative role of glucoamylase in work-related asthma was investigated by immunologic tests and specific inhalation challenges (SIC). Glucoamylase allergenic components were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. RESULTS: Skin prick tests to glucoamylase (10 mg/mL) gave a positive response in all patients. Further, a positive skin prick test to alpha-amylase was obtained in the four patients and to hemicellulase in two of them. SIC to glucoamylase elicited isolated early asthmatic responses in the three patients tested, and SIC to alpha-amylase elicited early asthmatic responses in two patients and a dual asthmatic response in another patient. Immunoblotting with glucoamylase showed several IgE-binding bands with molecular masses between 33 and 96 kD. IgE-inhibition assays showed scarce to moderate allergenic cross-reactivity between glucoamylase and alpha-amylase. CONCLUSIONS: These bakers had developed IgE-mediated occupational asthma to glucoamylase and alpha-amylase. Fungal glucoamylase is widely used as a baking additive and this enzyme may give rise to allergic respiratory reactions among exposed workers.

Adult↗