Background: Cryptococcosis causes significant morbidity and mortality in solid organ transplant (SOT) recipients. However, data regarding clinical characteristics and long-term outcomes of cryptococcosis in this population remain scarce.
Methods: We performed a single-center, retrospective study including all adult SOT recipients who were diagnosed with cryptococcosis during the study period of January 1, 2008 to December 31, 2017. Cryptococcosis was diagnosed according to EORTC/MSG revised criteria.
Results and Discussion: Thirteen patients were included in the study. There were 8 men (61.5%) and median age was 63-year-old (range 41-78). Study population included 5 kidney, 4 lung, 3 liver and 1 heart-lung transplant recipients. Median onset of the disease was 18 months after transplant (1 week to 8 years). Four patients (30.8%) had isolated pulmonary cryptococcosis and six patients (46.2%) had more than one organ involvement. Among 6 patients who had positive cerebrospinal fluid (CSF) culture, two-third had lymphocytic pleocytosis. High CSF protein level and low surgar level were noticed in 83% and 17%, respectively. CSF cryptococcal antigen was positive in only half of these patients, while serum cryptococcal antigen was detected in all patients. Most patients received liposomal amphotericin B with or without flucytosine as induction therapy, followed by fluconazole as consolidation and maintenance treatment.  Immune reconstitution inflammatory syndrome (IRIS) occurred in 2 patients, which resulted in one death. Both of them had disseminated diseases. One had IRIS during consolidation therapy, while one patient who received 7 months of antifungal therapy, developed IRIS 2 months after treatment discontinuation.  Overall 1-year survival rate was 69.2%. All patients (2/2) who had very early onset disease (<1 month) died from cryptococcosis. Overall 1-year graft survival rate was 84.6%.
Conclusion: Cryptococcosis after SOT  occurred late after transplant. It was associated with poor survival. Higher fungal associated mortality rate is associated with very early onset of disease and immune reconstitution syndrome.