At a median of 3 days following admission to the ICU, a diagnosis of invasive pulmonary aspergillosis was determined for 19% of the 432 influenza patients. Similar incident percentages of invasive pulmonary aspergillosis occurring for type A and type B, 71/355 (20%) and 12/77 (16%) patients respectively, showed that there was no clear association of the disease development with influenza subtypes that occurred during different annual seasons.
AspICU or EORTC/MSG criteria characterized only 43% and 58% of cases as proven or possible aspergillosis, respectively. On the other hand, stringent mycological tests yielded better invasive pulmonary aspergillosis classification, with 63% of BAL cultures being positive for Aspergillus, 88% of BAL galactomannan tests being positive, and 65% of serum galactomannan tests being positive in the 81/83 patients tested.
The study found that, for influenza patients, being immunocompromised more than doubled the incidence of invasive pulmonary aspergillosis, at 32% versus the 14% of those patients who were nonimmunocompromised. In contrast only 5% in the control group developed invasive pulmonary aspergillosis.