Purpose: to investigate the incidence and mortality of cryptococcal disease in solid organ transplant recipients in our medical center.
Methods: The diagnosis of cryptococcosis required a positive culture and/or positive cryptococcal antigen together with compatible clinical picture. Cases were electronically searched and identified from microbiology and pathology medical records.
Results: During a 10 year period (1989-1998), 41 cases of cryptococcosis were identified, all secondary to Cryptococcus neoformans. The follow-up was for a median of 5 yrs after transplantation. The cases included: pneumonia (14), disseminated (14), meningitis (9), and other sites (4). The patients comprised liver (24), heart (10), kidney (6), and lung (1) recipients. The immunosuppression treatment included tacrolimus or Cyclosporine A together with steroids. The mean age was 52.8 yrs. (s.d. ± 10.4). There were 29 (70.7%) males. The diagnosis of cryptococcosis was made at a median of 11.8 months (range 16 days- 16 years) after organ transplantation. Cryptococcosis occurred more frequently among heart recipients compared to other organs (p=0.005). The average yearly incidence of cryptococcosis per 1000 transplants was: 5.3, 1.3, 0.6, 0.4 for heart, liver, kidney and lung recipients, respectively. The mortality associated with cryptococcosis was 22%, and was higher in patients with disseminated infection (p=0.04), and in heart recipients (p=0.18).
Conclusions: Cryptococcosis is a late infection and is associated with high mortality after solid organ transplantation. The reason why it tends to occur more frequently among heart recipients compared to other solid organs remains unclear.