Occupational Asthma in Antibiotic Manufacturing Workers: Case Reports and Systematic Review

Figure 1

Changes in FEV₁ and histamine reactivity following bronchial provocation testing in four antibiotic manufacturing workers. Serial FEV₁ measurements (y-axis) are plotted against time after provocation (x-axis); a fall of greater than 15% from baseline indicated a significant response. A late reaction (greater than two hours after challenge) is seen in all cases; an early reaction was also seen in case c. The numerical value associated with each challenge plot is the postchallenge histamine PC₂₀ result (mg/ml histamine): the lower the PC₂₀ the greater the degree of bronchial hyperresponsiveness.

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