NEW YORK, Oct 26 (Reuters Health) -- A scuba diver's life-threatening asthma attack some 27 meters (almost 90 feet) below the surface was apparently caused by exposure to pollen from the Mediterranean nettle Parietaria, according to Italian researchers.
The investigators warn divers who are allergic to pollen to make sure that a filter is used to remove allergens from air used to fill air tanks.
Reporting in the September issue of the Journal of Allergy and Clinical Immunology, Dr. Gennaro D'Amato and colleagues, of Azienda Ospedaliera ad Alta Specialita A. Cardarelli, Naples, note that their patient had had "long experience of underwater diving without untoward effects."
The 37-year-old man also had bronchial asthma and had tested positive for allergy to the nettle, including "positive skin test responses and a high concentration of specific serum IgE to Parietaria pollen allergen, together with... symptoms in the Parietaria pollen season."
Before the dive in question, the diver used a new supplier to recharge his air tanks. When the investigators later inspected the premises of this supplier, they found that "the compressor was not fitted with an air filter and the area was rich in Parietaria plants," suggesting that air containing pollen from the plant was used to fill the tanks.
In subsequent experiments using air from tanks and pollen traps, D'Amato's team detected "damaged granules of Parietaria pollen that could have released specific allergens responsible for the asthma in the diver."
The evidence that the asthma attack was pollen related is "very persuasive," D'Amato and colleagues say. They advise divers at risk for pollen-induced breathing disorders "to check that the air used to recharge their tanks is filtered to prevent the passage of respirable pollen grains."
NEW YORK, Oct 26 (Reuters Health) -- A scuba diver's life-threatening asthma attack some 27 meters (almost 90 feet) below the surface was apparently caused by exposure to pollen from the Mediterranean nettle Parietaria, according to Italian researchers.
The investigators warn divers who are allergic to pollen to make sure that a filter is used to remove allergens from air used to fill air tanks.
Reporting in the September issue of the Journal of Allergy and Clinical Immunology, Dr. Gennaro D'Amato and colleagues, of Azienda Ospedaliera ad Alta Specialita A. Cardarelli, Naples, note that their patient had had "long experience of underwater diving without untoward effects."
The 37-year-old man also had bronchial asthma and had tested positive for allergy to the nettle, including "positive skin test responses and a high concentration of specific serum IgE to Parietaria pollen allergen, together with... symptoms in the Parietaria pollen season."
Before the dive in question, the diver used a new supplier to recharge his air tanks. When the investigators later inspected the premises of this supplier, they found that "the compressor was not fitted with an air filter and the area was rich in Parietaria plants," suggesting that air containing pollen from the plant was used to fill the tanks.
In subsequent experiments using air from tanks and pollen traps, D'Amato's team detected "damaged granules of Parietaria pollen that could have released specific allergens responsible for the asthma in the diver."
The evidence that the asthma attack was pollen related is "very persuasive," D'Amato and colleagues say. They advise divers at risk for pollen-induced breathing disorders "to check that the air used to recharge their tanks is filtered to prevent the passage of respirable pollen grains."
