Dynamic research of serum cryptococcal capsular polysaccharide antigen titer and chest CT of pulmonary cryptococcosis after antifungal therapy

Abstract

Objective: To observe the dynamic changes of serum cryptococcal capsular polysaccharide antigen (CrAg) titer and chest CT of pulmonary cryptococcosis (PC) after antifungal therapy. Methods: A retrospective study was performed for patients with PC admitted to the Department of Pulmonary and Critical Care Medicine of the First Affiliated Hospital of Wenzhou Medical University from January 2015 to April 2018. Serum CrAg titers and Chest CT examination were performed for all the cases before and after treatment. The difference between immunocompetent hosts group and immunocompromised hosts group were compared and analyzed. Results: Eighty-two patients with PC including 46 male (56.1%) and 36 (43.9%) female were enrolled. Fifty-two (63.4%) patients were proven PC and thirty (36.6%) patients were probable PC. Forty-five (54.9%) patients had underlying diseases. Fifty-four (65.9%) patients were immunocompetent hosts and twenty-eight (34.1%) patients were immunocompromised hosts. The mean duration of treatment was (7.9±2.4) months and the mean follow-up was (24.0±10.0) months. Improvement (≥75%) in chest CT were found in 64.8% of the cases in immunocompetent group and 67.9% in immunocompromised group after 6 months' treatment. Improvement (≥75%) was found in 88.9% of the cases with patchy infiltrates or consolidation and only 63.0% in nodular or mass-like type and mixed patterns of PC. The serum CrAg titer of 55 cases ranged from 1∶4 to 1∶160 before treatment (median 1∶40) and decreased for all cases after treatment. The serum CrAg titer became negative in 20 cases at last. Mean time of serum CrAg titer turning negative was (11.8±8.1) months. The serum CrAg titer became negative or decreased to 1∶1 in 24 cases after treatment cessation, of whom the serum CrAg titer ranged from 1∶5 to 1∶160 before treatment (median 1∶20). The serum CrAg titer of 31 cases ranged from 1∶4 to 1∶640 before treatment (median 1∶64), of whom the serum CrAg detections were still positive after treatment cessation, and CrAg titer was 1∶10 (ranged from 1∶2 to 1∶160). Conclusions: In PC, chest CT improves after antifungal treatment, and the infiltrates or consolidation type of PC resolves faster than nodular or mass-like shadows and mixed patterns in CT. The serum CrAg titer decreases after antifungal treatment.