It may be fruitful to take an envir

It may be fruitful to take an environmental exposure history at a patient’s entry into the practice; when a patient has a family history of asthma, allergies or autoimmune disease;during prenatal or preconceptual counselling;whena patient links onset of symptoms to environmental exposures;when a patient reports puzzling, nonspecific symptoms;or when a patient or family presents with frequent office visits for various illnesses.In the sample case described earlier, a previously healthy patient presents with a 3-year history of various puzzling,nonspecific symptoms.