Invasive pulmonary aspergillosis: identification of risk factors

Aspergillosis is the second most frequent fungal infection after candidiasis in teaching hospitals. Clinical manifestations of pulmonary aspergillosis range from asymptomatic colonization to disseminated disease. The aim of this study was to identify the risk factors associated with invasive pulmonary aspergillosis, in patients with positive pulmonary isolation of Aspergillus species. A review was undertaken of all clinical records with pulmonary isolation of Aspergillus species at Reina Sofia University Hospital from January 1995 to December 1998. Data collected were: age, gender, history of smoking, past medical history, such as chronic pulmonary disease, immunosuppression, granulocytopenia in the past 6 months and during the last admission, history of surgery including within the last year of the study period, number of hospital admissions and clinical evidence of invasive pulmonary aspergillosis. To investigate all the possible risk factors for invasive pulmonary aspergillosis, a multivariable logistic regression model was used. 132 patients with positive pulmonary isolation were identified, of which 42.4% had clinical evidence of invasive pulmonary aspergillosis. The independent factors significantly associated with invasive pulmonary aspergillosis were: granulocytopenia in the past 6 months, immunosuppression in the last admission and the number of hospital admissions within the past year. Patients with a history of granulocytopenia in the past 6 months and immunosuppression in the last admission are the high-risk group for invasive pulmonary aspergillosis. However, invasive pulmonary aspergillosis can also occur in mild granulocytopenic or even immunocompetent patients.