Pulmonary fungal infections after bone marrow transplantation: the value of high-resolution computed tomography in predicting their etiology.

BACKGROUND: The correct diagnosis of etiology of fungal infection after bone marrow transplantation is very important to the choice of antifungal drugs and a premise for improvement of therapeutic efficacy. This study aimed to compare high-resolution computed tomography (HRCT) findings of the pulmonary fungal infections to determine whether the etiology of various fungal infections could be diagnosed with HRCT. METHODS: Eighty-five cases were enrolled. According to the pathogens responsible for fungal infections, the patients were classified into three groups including invasive aspergillosis (n = 52), candidiasis (n = 19) and cryptococcosis (n = 14) groups. All the patients underwent HRCT scans. Two independent radiologists retrospectively analyzed the HRCT scans regarding CT patterns and distribution of lung abnormality. RESULTS: Most fungal infections in the three groups occurred in the neutropenic phase. There was no significant difference in the constituent ratio of fungal infections at different phases after bone marrow transplantation among the three groups. Agreement between the two observers for all the CT characteristics of fungal infections was excellent (k > 0.75). There was a significant difference in occurrence ratio of mass among the three groups (P = 0.02). Occurrence ratio of mass (43.3%, 13/30) in the group with invasive aspergillosis was higher than in each of other two groups (20.0%, 2/10; 14.3%, 1/7). There was no significant difference in other CT characteristics of nodules or masses; including number, margin, halo sign, cavitation and air-crescent sign. There was no significant difference in number, margin, air bronchogram and distribution of air-space consolidation. CONCLUSIONS: The HRCT appearance of various pulmonary fungal infections has a great deal of overlap and is nonspecific. Mass is more common in invasive aspergillosis, which is helpful to the diagnosis of invasive aspergillosis after bone marrow transplantation.