Intensive care management of influenza-associated pulmonary aspergillosis

Severe pulmonary infections are among the most common reasons for admission to intensive care units (ICU). Within the last decade, increasing reports of severe influenza pneumonia resulting in acute respiratory distress syndrome (ARDS) complicated by Aspergillus infection were published.

To provide a comprehensive review of management of influenza-associated pulmonary aspergillosis in patients with ARDS.

Review of the literature pertaining to severe influenza-associated pulmonary aspergillosis. PubMed database was searched for publications from the database inception to January 2019.

In patients with lower respiratory symptoms, development of respiratory insufficiency should trigger rapid and thorough clinical evaluation, in particular in cases of suspected ARDS, including electrocardiography and echocardiography to exclude cardiac dysfunction, arrhythmias and ischaemia. Bronchoalveolar lavage should obtain lower respiratory tract samples for galactomannan assay, direct microscopy, culture, and bacterial, fungal and viral PCR. In case of positive Aspergillus testing, chest CT is the imaging modality of choice. If influenza pneumonia is diagnosed, neuraminidase inhibitors are the preferred approved drugs. When invasive aspergillosis is confirmed, first-line therapy consists of isavuconazole or voriconazole. Isavuconazole is an alternative in case of intolerance to voriconazole, drug-drug interactions, renal impairment, or if a spectrum of activity including the majority of Mucorales is desired. Primary anti-mould prophylaxis with posaconazole is recommended in haematology patients at high-risk. It may be considered in newly diagnosed influenza and ARDS, but ideally in clinical trials.

The rising reports of influenza-associated pulmonary aspergillosis in patients with ARDS, who are otherwise not considered at risk for fungal pneumonia demands heightened clinical awareness. Tracheobronchitis and Aspergillus in respiratory tract samples should prompt suspicion of invasive fungal infection and further work-up. The management algorithm should comprise bronchoalveolar lavage, CT imaging, sophisticated ventilator-management, rescue extracorporeal membrane oxygenation, and antifungal and antiviral therapy. To decrease the burden of influenza-related illness, vaccination is of utmost importance, specifically in patients with co-morbidities.