Prevention of Pneumocystis carinii pneumonia in cardiac transplant recipients by trimethoprim sulfamethoxazole.

Pneumocystis carinii pneumonia (PCP) continues to cause significant morbidity in recipients of solid-organ transplants. While some programs administer trimethoprim-sulfamethoxazole (TMP-SMX) prophylactically following transplantation, a prospective determination of the safety and efficacy of TMP-SMX in cardiac transplant recipients has not previously been reported. We therefore prospectively randomized 58 cardiac transplant recipients to receive TMP (160 mg)-SMX (800 mg) twice daily either three days per week (group B), or seven days per week (group C), or to receive no treatment (group A). Treatment began 14 days after transplantation and continued for four months. Age, sex, preexisting pulmonary pathology and immunosuppressive protocols did not differ among the groups. Of 17 patients in the control group (A), 7 developed a clinical syndrome compatible with PCP, with the diagnosis histologically confirmed by bronchoalveolar lavage during the first four months following transplantation. In contrast, no patients in either the daily or intermittent therapy groups developed PCP during the study period (P < 0.005). Both doses of TMP-SMX were well tolerated, and discontinuation of therapy was not necessary in any patient. Total white blood cell count, azathioprine dose, and number of treated episodes of rejection per patient did not differ among the three groups. We conclude that TMP-SMX can safely and effectively be administered to prevent the occurrence of P carinii pneumonia during the first four months following cardiac transplantation.

OKT3 monoclonal antibody given for ten versus fourteen days as immunosuppressive prophylaxis in heart transplantation.

We have previously reported that murine antihuman monoclonal antibody OKT3 (Orthoclone OKT3) given for 14 days after heart transplantation is effective as immunosuppressive prophylaxis. The optimal protocol for OKT3 prophylaxis in heart transplantation is unknown, particularly the duration of OKT3 therapy. We conducted a consecutively allocated overlapping 6-month study with 68 heart transplant patients, comparing 14-day OKT3 (n = 34) to 10-day OKT3 treatment (n = 34). Both protocols included OKT3 given beginning 24 to 48 hours after operation, cyclosporine beginning on postoperative day 3, low-dosage steroids and azathioprine to prevent antibody production to OKT3, and a steroid pulse plus randomization to plus or minus vincristine after stopping OKT3. Pretransplant characteristics including age, sex, cause of congestive heart failure, and absence of positive pretransplant crossmatch were similar between the two groups. Although the infection rate was not significantly different between the two groups and mortality (one patient in each group) did not differ, 14-day prophylaxis decreased the number of treated rejection episodes per patient for the 6-month study (1.59 +/- 0.18 versus 2.24 +/- 0.19, p = 0.016). A 14-day course of OKT3 also decreased the risk of rejection during the 6-month follow-up period (p less than 0.05). In addition to having a decreased number of rejection episodes, patients in the 14-day protocol were also more likely to be withdrawn from maintenance steroids (79% versus 53%, p = 0.02). In conclusion, a measurable dose response efficacy can be demonstrated for 14-day versus 10-day OKT3 prophylaxis.(ABSTRACT TRUNCATED AT 250 WORDS)