Fungal empyema thoracis in cancer patients
April 20 2016
Fungal empyema thoracis (FET) is a rare life-threatening infection with mortality rates as high as 73% amongst cancer patients. Fortunately it is rare but there are too few reports of its diagnosis and management. This lack of data is particularly problematic in subjects with underlying malignancy, given their high risk for developing severe fungal infections.
A recent paper describes the outcomes of patients in a large cancer centre, who had a positive fungal isolate in their pleural fluid. Of the 708 positive pleural fluid cultures in the study period, 106 fungal isolates were recovered from a total of 97 patients and these were included in the study. In 69% patients, a solid tumour was the underlying mailgnancy.
The most frequently reported symptoms were dyspnea (78%), followed by cough (44%) and fever (27%). The pleural fluid analyses met criteria for an exudate in all cases. Of note one of the most important risk factors for FET caused by C. albicans was the history of an invasive procedure within the previous 30-day period, but not for Aspergillus species.
Yeasts accounted for 62% of the isolates recovered (n = 66), whereas a mold was identified in the remaining 38% (n = 40). The genera and species of the fungal isolates are summarized in Fig. 1. Candida species predominated with C. albicans being most frequently recovered (n =20), followed by C. glabrata (n =18) and C. tropicalis (n = 11). Aspergillus species (n = 12) accounted for the majority of the isolated molds and only one dimorphic fungus was identified (Coccidioides immitis). Overall, a concomitant bacterial organism was recovered from pleural fluid in 24 patients. Fig1
A total of 86 (88%) patients met criteria for proven or probable invasive fungal infection, while the remaining 11 cases did not fulfil criteria for such categories.
Most patients infected with Aspergillus or Candida received systemic antifungals but there are limited data on the effective penetration of antifungals in the pleural cavity. Two studies have indicated voriconazole achieves therapeutic concentration in the pleural fluid with similar trough concentrations to paired plasma levels; for Amphotericin B deoxycholate, pleural fluid concentrations are around 50% of those in plasma, or much lower in the case of liposomal amphotericin B. Penetration of echinocandins into the pleural fluid seems very low. (Review: Felton et al 2014). A chest tube was inserted in 30 patients and decortication (formal surgical drainage) was undertaken in 8. This is a relatively low rate of surgical intervention and more proactive surgical or thorascopic drainage is usually advocated. There are no data on the use of fibrinolytic therapy such as urokinase for FET, whereas it is helpful for complicated post-pneumonic empyema, and may avoid surgery.
Overall, 6-week mortality was high, with no significant differences between Candida and Aspergillus infection (31% vs. 45%, respectively [p = 0.48]). Interestingly only one of 11 patients with a rare mould infection died at 6 weeks so rare moulds were linked with a lower mortality.
Article :Nigo et al 2016
Review: Felton et al 2014