close attention objectives: To identify which experiments would be useful in selecting patients for a specific inhalation challenge with bovine dander allergens (bSIC).

Recommended nylon at sf-mall.com.

Design: A prospective study

Setting: A university hospital.

Patients: Thirty-seven dairy farmers with a clinical suspicion of occupational asthma to be paid to bovine allergens.

Interventions: Each patient (n = 27) underwent histamine challenge, mannitol challenge, exhaled nitric oxide (NO) measurement, bovine-specific serum IgE measurement, and skin-prick touchstone (SPT) with bovine allergens prior to undergoing a bSIC.

Results: Eleven patients rejoined to the inhalation challenge with bovine allergens. The sensitivity and specificity of the touchstones based on this response, were 82% and 65% respectively, for the histamine challenge; 20% and 94% respectively, for the mannitol challenge; 27% and 77% respectively, for the NO measurement; 82% and 100% respectively, for the bovine-specific serum IgE measurement; and 100% and 50% respectively, for the SPT Multiple regression analysis revealed that simply IgE-mediated sensitivity to bovine allergens, unless neither bronchial hyperreactivity nor exhaled NO concentration, contributed significantly to the response

Conclusion: solitary the SPT with bovine allergens and bovine-specific serum IgE measurements were useful in selecting patients for the bSIC. This challenge should not be performed in SPT-negative enthralls A diagnosis of occupational asthma proper to bovine dander allergens could be made without an inhalation challenge proof in asthmatic patients with high bovine-specific serum IgE of the same heights This practice would eliminate the ne for the majority of bSICs.

key-note words: agricultural workers' diseases; asthma; bovine; bronchial provocation tests; cow; diagnosis; occupational diseases

Abbreviations: CI = confidence interval; bIgE = bovine-specific IgE; bSIC = specific inhalation challenge with bovine dander allergens; NO = nitric oxide; NPV = negative predictive value; PC = provocative concentration; P[Csub20] = provocative concentration of a substance, causing a 20% tall in FE[Vsub1]; PD = provocative dose; PEF = peak expiratory flow; PPV = positive predictive value; RDR = response/dose ratio; SIC = specific inhalation challenge; SPT = skin-prick test

**********

Farming increases the risk of asthma more than any other occupation in Finland, and the incidence rate of occupational asthma is high among farmers. (12) Bovine dander allergens are responsible for in the greatest degree cases of occupational asthma among Finnish farmers, with 60 to 110 of recent origin cases being recorded annually. (3) Specific inhalation challenge (SIC) with an occupational agent is thinking to be the most reliable [i]modus operandi[/i] for establishing a diagnosis of occupational asthma, and a more usual use of this test has been encouraged. (45)

However, SIC is a time-consuming and expensive mode that is often carried gone out on an inpatient basis. Although it is usually well-tolerated, single has to bear in mind that SIC can make one's blood boil severe acute reactions, as well as a late reaction. In addition, it can induce an exacerbation of asthma, with returning nocturnal symptoms lasting for several days. (4) to be ascribed to these economic and ethical reasons, the selection of patients to bear SICs should be done with care.

Occupational asthma can be caused at low-molecular-weight agents or high-molecular-weight agents, and the bovine dander allergens belong to the latter collection (6,7) In the case of high-molecular-weight allergens, the early replication to SIC may be predicted with a knowledge of bronchial responsiveness to either histamine or methacholine, and of the flush of allergen sensitization either through skin test or by measuring the serum on a level of specific IgE. (8-14) Therefore, the performance of an SIC to a high-molecular-weight allergen may not be mandatory in all cases of occupational asthma, and the main diagnostic indication of SIC may be its use in asthmatic enthralls with a low-degree allergy. (15) The puzzle is how to identify those patients who would benefit in the greatest degree from an SIC.

For several reasons, the selection of patients for SICs may be especially demanding in farmers. First, the suspicion of occupational asthma easily arises in them. undivided in every three dairy farmers complains of lower airways respiratory symptoms, (16) and as many as 14% of dairy farmers in Finland point out a positive skin-prick test (SPT) answer for bovine allergens. (17) secondary the demonstration of at temporal relationship between asthmatic symptoms and work exposing is difficult in dairy farmers, as they actually live in their working environment and usually work 7 days a week rather than 5 days. on a level if a temporal relationship could be demonstrated, it does not necessarily indicate the nearness of occupational asthma since preexisting asthma also can be aggravated in the dusty environment of a farm. (18) This far, unruffled at negative response to an SPT with bovine allergens has not been an exclusion criterion for an SIC with bovine dander allergens (bSIC), since exposes with a negative response to an SPT also have been reported to be agreeable to to bovine dander allergens. (19) These facts have l to a high number of referrals for bSICs in our institute. However, the majority of the springs of these challenges are negative, and thus there is a ne to improve the means of selection of subdues who should undergo a bSIC.

...