Invasive Aspergillosis in the Intensive Care Unit

Data regarding the incidence of invasive aspergillosis (IA) in the intensive care unit (ICU) are scarce, and the incidence varies. An incidence of 5.8% in a medical ICU has been reported. The majority of patients did not have a hematological malignancy, and conditions such as chronic obstructive pulmonary disease and liver failure became recognized as risk factors. Diagnosis of IA remains difficult. Mechanical ventilation makes it difficult to interpret clinical signs, and radiological diagnoses are clouded by underlying lung pathologies. The significance of a positive respiratory culture result is greatly uncertain, because cultures of respiratory specimens have low sensitivity (50%) and specificity (20%-70%, depending on whether the patient is immunocompromised). The use of serologic markers has never been validated in an ICU population. Limited experience with the detection of galactomannan in bronchoalveolar lavage fluid specimens has yielded promising results. Because of a delay in the diagnosis of IA, the mortality rate exceeds 50%. Recently, our therapeutic armamentarium against IA has improved. Data concerning the safety and efficacy of new antifungal agents in the ICU setting, however, are lacking.