Comparison of caspofungin and trimethoprim-sulfamethoxazole combination therapy with standard monotherapy in patients with Pneumocystis jiroveci pneumonia following kidney transplantation: a retrospective analysis of 22 cases

Pneumocystis jiroveci pneumonia (PCP) is one of the most common and fatal opportunistic infections of renal transplant recipients. The objective of this retrospective study was to compare the therapeutic effect and safety of caspofungin and trimethoprim-sulfamethoxazole (TMP-SMZ) combination therapy with standard TMP-SMZ monotherapy in 22 patients with severe PCP following kidney transplantation. The presence of P. jiroveci was determined by direct fluorescence staining, PCR analysis, detection of beta-1, 3-glucan and serum lactate dehydrogenase levels. Thirteen patients received combination therapy, and nine patients received standard TMP-SMZ monotherapy for PCP. There were no significant differences in the baseline demographics and clinical characteristics were detected. Patients in the combination therapy group experienced better overall outcomes characterized by reduced duration of increased body temperature (P < 0.001), respiratory intensive care unit stay (P < 0.001), less requirement for mechanical ventilation (P = 0.005) and shorter high dosage TMP-SMZ treatment course (P < 0.01). 44.4% of patients receiving standard TMP-SMZ progressed to acute respiratory distress syndrome (ARDS), none of the patients in the combination therapy group experienced ARDS (P = 0.017). In addition, patients in the combination treatment group had greater PaO2/FiO(2) (P = 0.007), and experienced less neutropenia. Two patients in the TMP-SMZ monotherapy group died, while no deaths were observed in patients receiving combination therapy. In conclusions, PCP patients receiving caspofungin and TMP-SMZ co-treatment may experience better clinical outcomes with fewer side effects. Large-scale, prospective studies are needed to confirm that the improved clinical outcomes were due to the combination therapy.