porcine pancreatic extracts ( ppe ) , composed of -amylase and lipase , are widely used as a digestive drug in this country ; however , they can induce ige - mediated occupational rhinitis or asthma in bakery workers or those involved in the pharmaceutical industry ( 1 - 3 ) . although it is widely accepted that allergic rhinitis may precede asthma , few studies have reported about occupational rhinitis developing into occupational asthma ( 4 ) . this is the first case of occupational rhinitis progressing into occupational asthma during a 2-yr follow - up period with chronic exposure to digestive enzymes . a 31-yr - old female who had dispensed digestive drugs to admitted patients during 6 yr of employment as a university hospital nurse presented to allergy clinic 2 yr ago and complained of rhinorrhea and sneezing , but no asthmatic symptoms , when handling ppe powders . the patient was non - atopic and had no history of medical illness or family history of allergic disease . to evaluate her ige responses , a skin prick test ( spt ) was performed , and strongly positive responses were generated to ppe and -amylase ( 5 + and 3 + wheal ratios of allergen to histamine , respectively ) . ppe and other medicinal extracts collected from her workplace were prepared according to the previously described method ( 5 ) and used to detect serum - specific ige by enzyme - linked immunosorbent assay ( elisa ) . the positive cutoff value for a high level of serum - specific ige antibody was defined as the mean3 sd ( standard deviations ) of the absorbance value from unexposed healthy controls . the patient showed high levels of specific ige to ppe and -amylase by elisa ( 1041 and 1003 absorbance value , respectively ) . to confirm bronchial sensitization , a methacholine bronchial challenge test ( mbt ) and a specific bronchial provocation test ( bpt ) were performed with ppe , and both generated negative responses ( table 1 ) . antihistamine and a topical steroid were recommended to control her rhinitis symptoms , and she continued working in the same environment . two years later , she revisited our allergy clinic complaining of rhinitis and additional asthmatic symptoms . a second spt showed increased responses to ppe and -amylase ( 6 + and 6 + wheal ratios of allergen to histamine , respectively ) , and her serum - specific ige level was found to be highly elevated by elisa ( 720 and 718 absorbance values and respectively ) . a second mbt demonstrated positive responses at 1.36 mg / ml , and the bpt showed an early asthmatic response after inhalation of ppe ( table 1 ) ; both tests were performed as previously described ( 5 ) . this case demonstrates that ppe powder inhalation can induce occupational rhinitis , and furthermore develop into   occupational asthma when the causative allergen is not avoided in an exposed nurse working in a hospital . it is commonly accepted that allergic rhinitis precedes the development of asthma , although reports on allergic rhinitis turning into asthma are few , especially in a hospital nurse by drug powder . the patient had been diagnosed as having occupational rhinitis , due to the work - related rhinitis symptoms , strongly positive responses in the spt , and high serum - specific ige levels to ppe and -amylase , but not in the mbt and specific bpt . after 2 yr , she developed occupational asthma , showing the additional symptoms of lower respiratory tract and a positive response on the mbt and specific bpt . ppe are composed of -amylase and lipase , which are common components of digestive enzymes . it may cause asthma , rhino - conjunctivitis , allergic contact dermatitis , and contact urticaria ( 8) . a community - based study recently reported that enzymes could be a specific occupational risk ( 9 ) . there have been some reports of occupational asthma induced by these enzymes inhaled during the course of work , predominantly among pharmaceutical industry workers ( 10 - 13 ) . in our preceding reports , we detected occupational allergy to enzymes , such as -amylase and empynase among hospital personnel ( 5 , 14 ) . the major pathogenic mechanism of occupational allergies induced by high - molecular - weight drugs is an ige - mediated response ( 15 ) . the subject of this case had strongly positive responses in the spt and a high serum level of specific ige by elisa to both ppe and -amylase . these findings suggest that the pathogenic mechanism of occupational rhinitis is an ige - mediated response , and chronic exposure to ppe can result in occupational asthma via an ige - mediated reaction . in this study , the patient showed positive responses to both ppe and -amylase by spt and elisa , which may indicate that -amylase is the major allergenic component within the ppe . in our preceding study , it had been demonstrated that ppe and -amylase had extensive cross - allergenicity by ppe and -amylase elisa inhibition test , and shared one strong ige binding component by ige immunoblot study . however , lipase showed minimal inhibition for both ppe and -amylase elisa inhibition tests , and a lesser degree of inhibition on lipase elisa inhibition test ( 5 ) . in conclusion , it is important to carefully examine , treat , and follow patients with occupational allergic rhinitis , and remove them early enough from allergen exposure , in order to prevent the disease progressing to asthma .
porcine pancreatic extracts ( ppe ) , which are widely used as a digestive drug in korea , are composed of -amylase and lipase . such enzymes are commonly described as occupational allergens . 
 this is the first report of occupational rhinitis caused by ppe developing into occupational asthma in a hospital nurse . 
 she showed strong positive response in the skin prick test ( spt ) ( 5 + , wheal ratio of allergen to histamine ) and had a high serum - specific ige level to ppe , but showed a negative response in the methacholine bronchial challenge test ( mbt ) . 
 she had been exposed to ppe intermittently with intermittent medications for rhinitis . 
 two years later , she presented with rhinitis and additional asthmatic symptoms . 
 in contrast to her first visit , she showed a positive response in the mbt , and developed bronchoconstriction in the ppe - bronchial provocation test ( bpt ) . 
 these findings suggest that inhalation of ppe powder can induce ige - mediated occupational rhinitis in a hospital setting , which will develop into occupational asthma if avoidance is not complete .