"Aspergillus fumigatus"--a pathogen and allergen.

Aspergillus fumigatus is being increasingly recognised as causing various pathological conditions in man, animals and birds. In man the use of antibiotics has increased the importance of fungi in various clinical situations as opportunistic infective agents. In man, cavities in the lung are often (20 per cent) colonised by Aspergillus species, nearly always A. fumigatus. The mycetoma so formed can be specifically diagnosed by finding precipitating antibodies to A. fumigatus in the serum. In an asthma clinic, the findings of an immediate positive prick skin test to A. fumigatus, with or without precipitating antibodies to the fungus, confirms the diagnosis of pulmonary aspergillosis. These asthmatic patients develop transient lung infiltrations and proximal bronchiectasis, so that they eventually develop some degree of irreversible airways obstruction. Except for a small number of old patients, there are usually multiple positive type I skin responses to other inhalant allergens which will include other aspergilli species. Basically the complaint is a complication of allergic asthma. When first seen the patients often have treated with repeated courses of antibiotics for presumed infective asthma. Some of the findings in 86 asthmatic patients suffering from pulmonary aspergillosis will be presented.