Laboratory and clinical evaluation of a portable computerized peak flow meter

A mini-Wright based peak flow meter (VMX Mini-Log), which stores the readings together with the time and date of each measurement, has recently been marketed but has not yet been evaluated. The accuracy, reproducibility, and interdevice variability of this instrument were investigated using a pneumotachograph connected in series as a standard. Flows from 100 to 700 L/min were generated by an explosive decompression chamber. The performance of this instrument was also tested in 20 normal subjects and in 20 patients with airflow obstruction. The accuracy of the instrument was expressed as the percentage of error, and reproducibility and interdevice variability were assessed using the coefficient of variation. In the laboratory evaluation, all devices recorded flow rates that were within +/-10% of the pneumotachograph readings at flows between 200 and 600 L/min. At the extreme flow rates of 100 and 700 L/min, the mean error was higher than 10%. The reproducibility of the VMX was within +/-5% at all the flows tested. The interdevice variability was less than 5% at flow rates between 200 and 700 L/min. When tested on normal subjects with PEF between 400 and 700 L/min, the VMX performed well. In patients with airflow obstruction, four devices had greater than 10% error. The largest error was observed in those patients with PEF below 200 L/min. The VMX Mini-Log peak flow meter is accurate and precise in the flow range between 200 and 600 L/min. Its performance, however, may be affected in subjects with airflow obstruction and PEF below 200 L/min.

In vitro T-lymphocyte response and house dust mite-induced bronchoconstriction

BACKGROUND

There is considerable evidence that T cells may play an important role in asthma. The purpose of this study was to determine whether the responsiveness of T lymphocytes to mite allergen stimulation in vitro is a determinant of bronchial response to house dust mite (HDM) allergen challenge in subjects who are allergic to HDM.

METHODS

Peripheral blood was taken from seven healthy nonatopic subjects and 23 subjects with positive skin test reactions to HDM. Of the subjects in the latter group, 16 had an asthmatic reaction on inhalation challenge with HDM extract (HDM-responders), whereas the remaining seven had a negative reaction (HDM allergic). The proportion of subsets of T lymphocytes and their activation and the amount of IL-2, IL-4, IL-5, and interferon-gamma released in the supernatants with and without stimulation with the HDM extract were determined.

RESULTS

Without stimulation, the proportions of subsets of T lymphocytes and their activation were similar between groups. When stimulated with the HDM allergen, the proportion of CD4+CD25+ cells from HDM responders was significantly higher than those in the control group. Comparison within groups of cell cultures with and without stimulation with the mite allergen showed that the proportion of CD4+, CD4+CD25+, CD4+/CD8+, and CD3+HLADR+ cells were significantly increased in HDM responders with stimulation; there was a trend for CD4+CD25+ cells to be increased in the HDM-allergic subjects; no increase in any T-lymphocyte subsets was found in the control subjects. The release of IL-5 was significantly greater in HDM responsers than in the other two groups. The severity of the immediate asthmatic reaction was significantly associated with the degree of nonallergic bronchial hyperresponsiveness and the amount of IL-5 released but not with the level of specific IgE to the mite allergen or subsets of T lymphocytes with and without stimulation.

CONCLUSION

The findings suggest that responsiveness of T lymphocytes to allergen challenge in vitro may play a role in determining the bronchial response to the allergen in vivo.

Diversity of allergens causing occupational asthma among cereal workers as demonstrated by exposure procedures

BACKGROUND

Occupational asthma among cereal workers is frequently due to cereals but other allergens can also be responsible.

OBJECTIVE

We evaluated the allergens causing occupational asthma in the patients who had been diagnosed in our Department during the last 5 years. Specific bronchial reactivity to the implicated allergens was assessed and compared by standardized bronchial challenge.

METHODS

Twenty-one patients (12 bakers, three millers and six farmers) were studied. We carried out in vivo tests (skin and challenge tests) and in vitro tests (specific IgE measurement) with cereals, enzymes, soyabean, storage mites and egg. A definitive diagnosis was established by means of specific bronchial provocation tests (BPT), except in three patients in whom it could not be carried out due to the severity of their asthma. In these cases the causative agent had to be determined by means of conjunctival challenge.

RESULTS

Cereals were the main sensitizers among bakers (75%) and farmers (66%). Bakers were also sensitive to alpha-amylase (41%) and soyabean (25%), and farmers, to soyabean (33%) and storage mites (33%). Occupational asthma was due to cereals, soyabean and storage mites among millers.

CONCLUSIONS

Besides cereals, other allergens such as enzymes, leguminous, egg and storage mites can be the causative agents of occupational asthma among cereal workers. Sensitization to different allergens in the different jobs is very likely due to differences in exposure.

Major cat allergen (Fel d I) levels in the homes of patients with asthma and their relationship to sensitization to cat dander

BACKGROUND

Exposure and sensitization to the major cat allergen, Felis domesticus allergen I (Fel d I), significant causes of allergic respiratory disease. Many patients who are allergic to cats, however, do not own a cat and there is not an obvious source of allergen in their home environment.

OBJECTIVE

We investigated the levels of Fel d I in dust from homes of 120 subjects with asthma in two climatologically diverse Canadian cities (Vancouver and Winnipeg). Fel d I levels were related to exposure to cats as well as to skin reactivity to cat dander.

METHODS

Dust samples from bedroom floors and mattresses were collected in four different seasons and Fel d I content was determined by 2-site monoclonal antibody based-ELISA.

RESULTS

Although only 18 patients (15%) were cat owners, detectable levels of Fel d I were found on at least one occasion in all homes. The geometric mean concentration of Fel d I on floors was 1.15 micrograms/g of dust (range 0.07 to 26.3 micrograms/g) and on mattresses 0.89 micrograms/g (range 0.01 to 17.4 micrograms/g). Seasonal variation of Fel d I levels was only observed in Winnipeg, where Fel d I concentrations were highest in the winter and spring compared with either summer (P < .05) or autumn (P < .005). The highest Fel d I levels were found in homes with a cat (P < .05), however, rather high levels were also found in homes of patients who did not have a cat but visited others with cats. Cat dander was the most frequent sensitizer (60%) in these patients but no correlation was found between the size of the wheal induced by cat dander extract and Fel d I levels in dust samples.

CONCLUSION

Cat allergen was universally found in homes of asthmatic patients and this may explain the high frequency of cat sensitization among patients with asthma in these two cities. A seasonal variation in cat allergen was observed in Winnipeg with no variation in Vancouver.

Peak expiratory flow monitoring is not a reliable method for establishing the diagnosis of occupational asthma

This is a study of the reliability of peak expiratory flow (PEF) monitoring using a portable computerized peak flow meter, the VMX Mini-log, in 17 subjects referred for suspected occupational asthma. Subjects were requested to monitor their PEF six times daily using the VMX Mini-Log for 2 wk at work and at least 10 d away from work. They were unaware that their readings were stored by the flow meter in addition to the digital readout. Four subjects (22%) were unable to complete the monitoring. The results recorded by the subjects were compared with the results recorded by the VMX. Of those who completed the monitoring, only 55.3% of the records were completely accurate in terms of the value and the timing of the measurements, 23.3% were inaccurate either in terms of the recorded value or of the timing of the measurement, and the remainder were fabricated results (not recorded by the Mini-Log). Our results suggest that PEF monitoring using ordinary peak flow meters for assessment of work-relatedness of asthma has limitations and is not reliable.

Pickled onion-induced asthma: a model of sulfite-sensitive asthma?

BACKGROUND

Asthma elicited by sulfite ingestion has been mainly described in steroid-dependent and in non-atopic asthmatics. We have studied a group of 18 young extrinsic asthmatics who presented with asthma attacks immediately after eating pickled onions.

OBJECTIVE

The aim of this study is to ascertain if these asthma attacks are elicited by sulfites contained in pickled onions and the influence of the dose and pH of onions.

METHODS

The bronchial hyperreactivity of the patients was assessed by a methacholine challenge test. Oral challenge tests were performed with sodium metabisulfite (MSB) diluted in lemon juice at pH 4.2 and at pH 3.3 (only in patients who did not react with pH 4.2). Two types of pickled onions, Spanish and Dutch pickled onions, were used for oral challenge in seven of the patients. The Monier-Williams method was used to measure the SO2 concentration in pickled onions.

RESULTS

The oral provocation test with MBS, pH 4.2, elicited a positive response in six patients (33.3%) and the test at pH 3.3 was positive in three out of 12. No significant difference in PD20 values was found between these groups. Three of the seven patients challenged with Spanish pickled onions had a positive reaction but had no reaction with Dutch pickled onions. The SO2 concentration in Spanish pickled onions varied between 765 and 1182 ppm while in Dutch pickled onions were 200 ppm; this exceeded the permitted level (100 ppm). SO2 release in Spanish pickled onion samples was nearly 2.5 times higher when the pH of the sample decreased from 4.2 to 3.3.

CONCLUSION

High levels of SO2 in Spanish pickled onions, and their low pH (3.3) would be the responsible factors of the asthmatic outbreaks after ingestion of Spanish pickled onions by these patients.

Green bean hypersensitivity: an occupational allergy in a homemaker

As a member of the legume family, the green bean is frequently associated with food allergy. However, allergic reactions caused by skin contact or by inhalation of vapors from boiling legumes are rare. This article presents a case of occupational asthma in a homemaker; symptoms occurred during preparation and cooking of raw green beans. Skin prick, rub, and bronchial provocation tests were performed on the patient. In vitro tests were done with the serum samples of the patient and 10 control subjects (5 atopic and 5 nonatopic). Test results indicate that the patient has type I hypersensitivity to raw green bean antigen(s). This case is of interest because it demonstrates that a food allergen, when inhaled, can induce respiratory symptoms in sensitized patients and may even be the source of primary sensitization.

Susceptibility of a grass-pollen oral immunotherapy extract to the saliva and gastric fluid digestive process

The oral and sublingual immunotherapy is still a controversial therapeutic procedure. One of the problems is knowing how much allergenic activity could the extracts loss due to the digestive process into the mouth and stomach. Using a grass-pollen oral and sublingual immunotherapy extract, we studied its degradation until reaching the small intestine. For this purpose we employed an in vitro model using the RAST-inhibition assay. We observed a 3.8 fold loss of allergenic activity after a 30 sec-incubation with saliva; a subsequent 5 min-incubation with gastric fluid got a final loss of allergenic activity of 10.3 fold. The incubation times were those expected occurring during the ingestion of the extract. It was surprising that after the enzymatic and acid actions of the gastric fluid, an important degree of allergenic activity still remained in the extract. This issue should be taken into account when considering the dose to be administered in oral and sublingual immunotherapy.

Asthma and contact urticaria caused by rice in a housewife

We report the case of an atopic housewife who presented with rhinoconjunctivitis-asthma and contact urticaria from handling rice and other cereals. She tolerated cooke cereals. Both skin prick tests with a rice extract (20% w/v) and a rub test with raw rice gave positive results. Bronchial challenge test with methacholine revealed a PC20 of 0.45 mg/ml. The challenge test with raw rice resulted in immediate and late clinical and spirometric responses; pretreatment with DSCG inhibited both responses. The histamine release test (HRT) with rice was positive, and we detected rice-specific IgE antibodies by REIA in the patient's serum. Skin prick tests, HRT, and RAST with a battery of cereals gave positive results. Finally, the rice REIA was inhibited by rice (75%), rye (63%), corn (64%), and wheat (51%) extracts.

Airborne contact dermatitis from Frullania

7 subjects, each giving a history of scaly or vesicular dermatitis in light-exposed areas after going for strolls to the park, the forest or the country during warm weather, were evaluated. Patch testing was carried out with Frullania dilatata and Frullania tamarisci as well as with 2 common members of the Compositae and to alantolactone and the sesquiterpene lactone mix. All the patients were positive to F. dilatata, 3 reacted to F. tamarisci as well, and 2 to florists' chrysanthemum. All of them except 1 gave positive responses to the sesquiterpene lactone mix, but only 3 reacted to alantolactone. Airborne contact dermatitis from these species of Frullania was considered to be the cause of their eczema. Patch testing with the sesquiterpene lactone mix seems to be a good screen for Frullania sensitivity; however, a variable pattern of response to these sesquiterpene-lactone-containing materials was observed, suggesting individual immunologic responses to them.

Occupational asthma and immunologic responses induced by inhaled carmine among employees at a factory making natural dyes

Carmine is a natural red dye widely used as a food coloring agent and for cosmetic manufacture. It is extracted from the dried females of the insect Dactylopius coccus var. Costa (cochineal). Although it has been reported that inhalation of carmine may give rise to occupational asthma and extrinsic allergic alveolitis, there is little evidence of its immunogenic capacity. We studied nine current employees at a factory making natural dyes and one former employee who had left this plant after occupational asthma developed. A current employee had work-related symptoms of rhinitis and asthma that were confirmed by bronchial provocation tests, and another worker had rhinitis. Immunologic sensitization to carmine and cochineal was evaluated by means of skin testing and determination of serum-specific IgE and IgG subclass antibodies by RAST and ELISA, respectively. The specificity of the RAST assay was investigated by RAST inhibition with different fractions of carmine. The three workers with respiratory symptoms had positive skin prick test reactions to both carmine and cochineal. An immediate response to the bronchial provocation test with carmine and cochineal was observed in the current employee with asthma. Specific IgE antibodies against carmine and cochineal were found only in this worker. RAST inhibition studies indicated that the main allergen had a molecular weight between 10 and 30 kd. Specific IgG antibodies against carmine and cochineal, mainly the subclasses IgG1, IgG3, and IgG4, were found in the 10 subjects surveyed. These findings suggest that carmine may induce immunologic responses, most likely IgE mediated in workers with symptoms of occupational asthma.

Hypersensitivity reactions to anthranilic acid derivatives

Anthranilic acid derivatives are a group of nonsteroidal antiinflammatory drugs that include glafenine and fenamates. We report a woman who had immediate adverse reactions to glafenine and meclofenamate sodium. Skin prick and intradermal tests were performed with solutions of glafenine and meclofenamate in phosphate-buffered saline (PBS) and with the drugs bound to human serum albumin (HSA). Prick and intradermal tests with PBS solutions were negative for both drugs as were prick tests with HSA solutions. Intradermal tests with HSA-glafenine, however, were positive at 20 minutes, and at 6 and 24 hours. Intradermal tests with HSA-meclofenamate elicited a positive response at 6 and 24 hours. These tests were negative when performed in control subjects. A leukocyte histamine release test and a RAST assay were negative for both drugs. The patient was challenged following a double-blind placebo-controlled oral procedure and tolerated therapeutic doses of aspirin, indomethacin, ibuprofen, dipyrone, diclofenac, piroxicam, and acetaminophen. The oral challenge with glafenine and meclofenamate reproduced the reactions (eliciting doses: 50 mg and 15 mg, respectively), and the patient also reacted to 30 mg of mefenamic acid, an anthranilic acid derivative she had never previously received. This is an exceptional case of selective adverse reactions to glafenine and fenamates, anthranilic acid derivatives, in a patient tolerating aspirin and other cyclooxygenase inhibitors. Our study implicates an immunologic mechanism, and the existence of cross-reactivity between the drugs (or some active metabolite generated in vivo).

A prospective safety-monitoring study of immunotherapy with biologically standardized extracts

We evaluated the safety of immunotherapy in 419 patients who attended our allergy department for treatment. They were suffering from rhinitis and asthma caused by sensitization to grass pollen or Dermatophagoides pteronyssinus. Immunotherapy was given by biologically standardized aluminum hydroxide adsorbed extracts according to a conventional schedule. Local reactions were recorded in 10.5% of the patients and systemic reactions in 4.8%. Only 0.37% of the doses administered were associated with systemic side-effects. We found that 84% of the patients who showed systemic reactions were asthmatic subjects (P < 0.01), and most of them were sensitized to D. pteronyssinus (71%). Side-effects occurred more frequently during the dose-increase period (P < 0.05). After 9482 doses had been administered, no anaphylactic shock or life-threatening reactions were registered. We believe the risk associated with immunotherapy to be drastically reduced when treatment is carefully monitored by skilled personnel. In such conditions, as shown by our study, immunotherapy is safe.

Cross-reactivity between quinolones. Report of three cases

Cross-reactivity between quinolones is uncertain. Recently, we studied three patients who had developed suspected allergic reactions to a quinolone. For all of them we performed skin test, histamine release test, RAST, and oral provocation with the suspected quinolone and also with another quinolone of the opposite generation. Five atopic and five nonatopic subjects were used as controls. Neither skin test, histamine release test, nor RAST was useful in the diagnosis. By means of oral controlled provocation, the reactions were reproduced, and all the patients also reacted to another quinolone. We concluded that cross-reactivity between quinolones seems to be very important, and avoidance of any quinolone should be recommended to any patient who has suffered an allergic reaction to one of these drugs.

Occupational asthma and contact urticaria from dried flowers of Limonium tataricum

Dried flowers of Limonium tataricum (LT) are widely used for semipermanent floral arrangements. We report a case of a floral industry worker in whom exposure to LT precipitated rhinoconjunctivitis, asthma, and contact urticaria. Studies revealed the presence of immediate skin test reactivity and positive leukocyte histamine release in response to LT extract. Specific anti-LT antibodies were detected in the patient's serum by direct RAST. Bronchial challenge with LT extract also resulted in an isolated immediate asthmatic response. Both the positive methacholine inhalation test and the significant changes observed in PEFR measurements when the patient handled LT supported the diagnosis of occupational asthma. These findings strongly suggest that an IgE-mediated immunologic mechanism is responsible for the patient's respiratory and cutaneous symptoms.

Fixed eruption caused by ciprofloxacin with cross-sensitivity to norfloxacin

A case of fixed eruption caused by ciprofloxacin is reported. To our knowledge, no other cases have been published. Cross-sensitivity with another fluoroquinolone has been demonstrated.

Occupational asthma in a hairdresser caused by persulphate salts

Persulphate salts, which are common constituents of hair bleaches, have occasionally been reported to cause occupational asthma in hairdressers. We describe the clinical and immunological studies carried out in a hairdresser who developed cutaneous and respiratory symptoms, about 1 year after being employed in a hairdressing salon. Skin prick tests with 1:5 w/v potassium and sodium persulphate extracts were positive in our patient at 15 min and negative in control subjects. The European standard contactans (ECDRG) and a battery of hairdressing agents were patch tested with positive result to KATHON CG (isothiazolinone). The methacholine-inhalation test showed airway hyperresponsiveness. Bronchial provocation test with a 1:50 w/v potassium persulphate extract elicited a nonimmediate asthmatic reaction, followed by recurrent nocturnal fall in FEV1 lasting up to 3 days after the test. Plethysmography results revealed air trapping caused by a marked increase of airway resistance 3 h after the specific bronchial challenge. Histamine release test was not conclusive, and the determinations of specific IgA, IgM, IgG and IgG subclasses by EIA and IgE by RAST against persulphate salts were negative.

Respiratory allergy to Aspergillus-derived enzymes in bakers' asthma

Baking and food industry workers are exposed to several powdered Aspergillus-derived enzymes with carbohydrate-cleaving activity that are commonly used to enhance baked products. We describe a retrospective study of sensitization to fungal alpha-amylase and cellulase on bakers. Five bakers in whom respiratory allergy symptoms developed when they were exposed to bread "improvers" that contained fungal alpha-amylase and cellulase were investigated by in vivo and in vitro tests. Type I hypersensitivity to these enzymes was demonstrated in the five patients by means of skin testing, histamine release test, positive reverse enzyme-immunoassay for specific IgE antibodies, and bronchial provocation test response to alpha-amylase or cellulase or both. Isolated immediate and dual responses to the bronchial challenge tests with these enzymes were observed. Immunoblot analysis with use of a pooled serum identified IgE-binding components in both enzymes. In the reverse-enzyme immunoassay-inhibition assays cross-reactivity between alpha-amylase and cellulase was not found, but some degree of cross-reactivity between alpha-amylase and A. oryzae, and between cellulase and A. niger was demonstrated. Four of the patients were also sensitized to cereal flour. Aspergillus-derived enzymes used as flour additives can elicit IgE-mediated respiratory allergy, and this fact has to be considered in the diagnosis and clinical management of bakers' asthma.

Recurrent pericarditis: a rare complication of allergen immunotherapy

We report on a 29-year-old woman suffering from hay fever due to grass and olive tree pollens. She developed recurrent pericarditis during her first course of immunotherapy with an alum-adsorbed pollen extract. A causal relationship was established between the allergen injections and the acute pericarditis episodes on two consecutive occasions, which presented with blood eosinophilia. Blood cultures and serological tests for microorganisms were negative. There were no signs of autoimmune disease or systemic vasculitis. To the best of our knowledge, allergen immunotherapy-induced pericarditis has not been previously reported.

Immediate allergy to natural latex: clinical and immunological studies

Since 1979 several reports of contact urticaria due to natural latex have been documented. In recent years cases of anaphylaxis, rhinitis, and asthma due to latex have appeared. Nine patients, studied in our clinic between 1986-1991, suffered immediate allergic reactions caused by rubber products. All showed an immediate skin reaction to latex extract. Rub testing with surgical gloves was positive in eight patients. Immunological techniques (RAST, ELISA, HRT) demonstrated specific IgE against latex. Specific bronchial provocation testing was performed in one patient who presented with asthma when she used latex surgical gloves. Patch testing to common rubber additives were negative in our patients. These results suggest that natural latex antigens present in rubber objects can cause hypersensitivity reactions probably due to IgE-mediated mechanisms.

Monoclonal antibodies against major allergen: Allergenic activity of affinity-purified allergen and depleted extract and development of a radioimmunoassay for the quantitation of the allergen

Several monoclonal antibodies (MAbs) were raised against Olea europaea pollen-extract components. Two of these antibodies, named OL 2 and OL 7, recognize two nonoverlapping, nonrepeating epitopes on the olive-allergen Ole e I, as demonstrated by different techniques. The allergen was purified in a single step by MAb-based affinity chromatography, and the allergen revealed a band at molecular weight 20 kd as well as a minor band at 18 kd on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The contribution of allergen Ole e I to the allergenic activity of O. europaea pollen extracts was determined from the effect of allergen depletion by affinity chromatography on skin reactivity and a histamine-release test. The removal of allergen caused a large reduction in the activity of the preparation in 25 monospecific olive-allergic patients. In agreement, the affinity-purified allergen demonstrated a similar response when it was compared with the whole extract in these assays. The results indicated that Ole e I is by far the most important olive-pollen allergen. A two-site solid-phase radioimmunoassay was developed for the quantitation of the allergen Ole e I in mass units. The assay was based on the MAbs, OL 2 and OL 7, and had a detection limit in the nanogram range. A good correlation was found between allergenic activity, as determined by RAST inhibition, and allergen content in 18 olive-pollen extracts. This result indicates that the assay can be a good alternative to RAST inhibition for the standardization of O. europaea extracts.

Bronchial asthma induced by chick pea and lentil

Allergic reactions to legumes through inhalation have rarely been described. We report the case of a 20-year-old man who experienced asthmatic attacks when exposed to the steam from cooking either chick pea or lentil. Type I hypersensitivity to the antigens in these legumes was demonstrated by means of immediate skin reactivity, histamine release tests, RAST and RAST inhibition. Specific bronchial challenges with the heated (75 degrees for 30 min) extracts of chick pea and lentil elicited isolated immediate responses.

Occupational asthma caused by alpha-amylase inhalation: clinical and immunologic findings and bronchial response patterns

Inhalation of dust from different enzymes can be the cause of occupational asthma in exposed workers. alpha-Amylase, derived from Aspergillus oryzae, is one of these enzymes, although there are few studies in the medical literature that refer to its allergologic properties and to clinical studies in sensitized patients. The results obtained in a study performed in 83 pharmaceutical-industry workers exposed to powdered alpha-amylase are described in this article. The existence of sensitization to this enzyme was demonstrated in 26 of the workers by positive skin tests. Specific IgE values were significantly higher in workers with positive skin tests than in workers with negative skin tests (p less than 0.001). The bronchial provocation test with alpha-amylase was positive in six of the 14 patients challenged, and only immediate bronchial responses were observed; the same type of response was obtained by nasal provocation. One of the workers had a positive response to oral provocation with this enzyme, presenting abdominal, skin, and respiratory symptoms a few minutes after ingestion. Consequently, we consider that the bronchial asthma presented by the workers was due to an immediate-type, IgE-dependent, immunologic mechanism.

Swiss chard hypersensitivity: clinical and immunologic study

Allergy to vegetables and fruits seems to be more prevalent in atopics, especially in birch pollen-sensitized individuals. We report a case of a grass pollen-sensitized woman, in whom the inhalation of vapor from boiling Swiss chard precipitated rhinoconjunctivitis and asthma. Type I hypersensitivity to Swiss chard was demonstrated by means of immediate skin test reactivity, specific IgE determination by RAST, basophil degranulation, histamine release test, and an immediate bronchial provocation test response to Swiss chard extract. The controls did not react to any of these tests. RAST inhibition assays suggest the presence of some cross-reactivity among Swiss chard and grass pollen antigens, as well as cross-reactivity between vegetables and weed pollens of the chenopod family.

Occupational asthma due to latex surgical gloves

Since 1979 several reports of contact urticaria due to natural latex have been well documented. Recent case reports suggest that rhinitis and asthma may also be due to rubber exposure. We describe an operating room nurse who was exposed at work to natural rubber (latex) due to the use of latex surgical gloves. After 25 years, she developed contact urticaria, rhinoconjunctivitis and acute asthma following the handling of rubber gloves for surgical purposes. She was symptom-free when on vacation. Skin prick testing demonstrated an immediate skin reaction to latex. Rub testing with surgical gloves was positive. Specific IgE antibodies to latex were found by indirect ELISA. Specific bronchial challenge with latex extract elicited an isolated immediate asthmatic reaction that was inhibited with cromolyn sodium pretreatment. Patch testing to common rubber additives was negative. These results suggest that latex present in surgical rubber gloves and probably acting as inhalant allergen may produce occupational asthma in exposed subjects, probably by means of an IgE-mediated mechanism.

Severe anaphylactic reaction to thymostimulin

Thymostimulin is a partially purified extract of calf thymus, consisting of a group of polypeptides with a total molecular weight of approximately 12,000 D. It is used as an immunologic response modifier in primary and secondary immunodeficiencies. We report a patient who had a severe anaphylactic reaction with the first injection of thymostimulin. Type I hypersensitivity to thymostimulin was suggested by an immediate skin test response, specific IgE determination by indirect ELISA and a positive histamine release test. This patient also reacted to bovine serum albumin (BSA), fetal calf serum (FCS) and cow hair and dander. The controls did not react to any of these tests. Clinicians need to be aware that the use of medical products of xenogeneic origin may lead to severe allergic reactions.

Adverse cutaneous reactions due to macrolides

Macrolides, which are widely prescribed and seldom produce hypersensitivity reactions, are considered to be safe drugs. We present five patients with generalized skin reactions due to erythromycin and/or spiramycin, proved by oral challenge tests. One patient showed reactions to both erythromycin and spiramycin. All skin prick and patch tests and histamine release tests with both macrolides were negative.

Serum sickness-like syndrome associated with minocycline therapy

A 19 year-old youth was taking oral minocycline and after 8 days he presented all four cardinal symptoms of serum sickness (urticaria, fever, lymphadenopathy and joint symptoms). C3, C4 and CH50 evolution imitate experimental serum sickness complement evolution. We exclude other causes of this syndrome. Although other hypersensitivity reactions have occurred with minocycline usage, to our knowledge serum sickness-like syndrome has not been previously reported with this drug.

Effect of nifedipine on skin prick tests

The immediate skin test due to interaction between allergen and mast cell bound IgE is one of the cornerstones in the clinical allergy workup. The release of histamine and other mediators from basophils and mast cells depends on the influx of Ca2+ into these cells when stimulated. The aim of this study was to evaluate the effect of common therapeutic doses of nifedipine (NFD), one of the calcium channel blockers, on the allergen skin tests. We prick tested 23 grass sensitive individuals with 7 different grass pollens at three times: at basal conditions (T0), 30 min. after having taken 20 mg of NFD s. l. (T1), and 17 of them after a week of receiving twice a day 20 mg of a NFD retard form (T2). The wheal surface obtained for each substance (allergen, histamine) at T0 was considered as basal value and compared with the one obtained at T1 and T2 for the same substance by the Wilcoxon's test. We found a significant increase in the wheal surfaces, both with allergen and histamine, at T1 and T2. In contrast to what could be expected, common therapeutic doses of NFD produce a discrete but statistically significant increase of the PT. Factors such as arteriolar vasodilation could be implicated. The increase of the allergen prick test and the increase of the histamine prick test both at T1 and T2 were not statistically different. Therefore, we do not think it necessary to stop NFD before allergen skin testing.

Stinging insect allergy: sensitization to vespids in Madrid and surroundings. Cross-reactivity study

The study comprised 28 patients from the centre of Spain (Madrid and surroundings) who had suffered systemic reactions when stung by vespids. Specific IgE antibodies to Vespula spp. and Polistes spp. venoms were measured by RAST. All patients had positive RAST to Vespula venom and half of them also had positive RAST to Polistes venom. A patient can be sensitive to both venoms due to either a clinical sensitization to both venoms, or common antigenic determinants. To differentiate these states we used a RAST inhibition assay. We could inhibit Polistes RAST with either Polistes or Vespula venom to a similar degree. Inhibition of Vespula RAST was possible with Vespula venom, but only to a limited degree with Polistes venom. Direct RAST and RAST inhibition studies indicate that in our geographic region sensitization to Vespula venom is more common than to Polistes venom and Polistes might have cross-reactivity in our patients.

Housewives with raw potato-induced bronchial asthma

Allergy to white potato has rarely been described. We report two cases of atopic patients, housewives, in whom peeling raw potatoes precipitated rhinoconjunctivitis and asthmatic attacks, and, in one of them, contact urticaria. Type I hypersensitivity to raw potato antigens was demonstrated by means of immediate skin test reactivity, specific IgE determination by RAST, basophil degranulation, histamine release test and an immediate bronchial provocation test response to raw potato extract. The controls did not react to any of these tests. Potato allergenic constituent is currently being investigated but, as far as we know, it is heat-labile and has an MW of more than 10 Kd.

Bronchial asthma caused by Lathyrus sativus flour

A 10-year-old child with asthmatic attacks related to Lathyrus sativus flour inhalation was studied in our department. Skin test and specific bronchial provocation challenge were positive. Specific IgE antibodies to Lathyrus sativus flour was demonstrated by indirect enzyme immunoassay. We suggest that our patient's allergic symptoms were due to the development of Type I allergic reactivity to L. sativus antigens.

Specific bronchial challenge in cockroach asthma

Clinical characteristics of allergic asthma due to inhalation of cockroach antigens have been reported sporadically in the literature. To assess the patterns of bronchial response in cockroach asthma we performed bronchial provocation tests (BPT) with cockroach extract in 25 asthmatic patients who had positive skin test with this extract. Of 25 patients, 23 had cockroach-specific-IgE-antibodies. Seventeen subjects presented only immediate asthmatic reaction, five patients had dual response (immediate + late), and one patient developed only late asthmatic response. BPT were negative in two patients who did not have cockroach-specific-IgE-antibodies. These results indicate that BPT with cockroach antigen is a very specific test for cockroach asthma. It shows immediate, dual and late responses, and correlates well with the presence of specific IgE antibodies against this allergen.