Pneumocystis pneumonia in solid organ transplant recipients: not yet an infection of the past

Abstract

Solid organ transplant (SOT) recipients are at risk for Pneumocystis pneumonia (PCP), especially in the first year post transplant. Although trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis substantially decreases this risk, there is little data or consensus on optimal duration of prophylaxis. Consequently, there is lack of standardization of prophylaxis duration (3months to lifelong, depending on organ group) in SOT programs. We performed a retrospective chart review of all cases of confirmed PCP, in adult kidney, pancreas, liver, and lung transplant recipients from 2001 to 2011 in our SOT program. Of 1241 patients followed in our clinic (657 kidney, 44 kidney/pancreas, 436 liver, and 104 lung or heart/lung), a total of 14 PCP cases were identified in 2 kidney, 1 kidney/pancreas, 5 liver, 5 single lung, and 1 heart/lung transplant recipient. At the time of PCP diagnosis, immunosuppression in most cases consisted of prednisone, tacrolimus, and mycophenolate mofetil (79% of patients), and 53% had previously received TMP-SMX for prophylaxis. None were on PCP prophylaxis at the time of illness onset. PCP occurred early in all 5 liver transplant recipients and in 1 kidney transplant recipient, none of whom had ever received prophylaxis (17-204days post transplant). Of those who had received 6months of prophylaxis (1 kidney, 1 kidney/pancreas), PCP occurred at 846 and 4778days, respectively. Late onset PCP occurred in lung recipients who had received 12months of prophylaxis (lung 645-1414days, heart/lung 1583days post transplant). Five patients had experienced acute rejection and 6 patients had cytomegalovirus (CMV) viremia on average 59 and 204days preceding PCP, respectively. Three deaths (1 liver, 2 lung) were thought to be directly related to complications of PCP. Our experience with late PCP cases in lung transplant recipients receiving only 1year of prophylaxis lends support to prolonged PCP prophylaxis in this group. Given the number of patients who had experienced an acute rejection episode or CMV disease preceding PCP in non-lung SOT recipients, consideration should be given to re-institution of PCP prophylaxis for a period of time after these events in kidney, kidney/pancreas, and liver transplant recipients.