Introduction: Kidney transplantation is the best available replacement therapy for patients with end- stage renal disease.Since first successful transplant in United States in the early 1950's, the kidney transplant has made a significant progress.The overall patient and graft survival has improved due to several factors including improved surgical techniques,availability of better immunosuppressive medicines and improved diagnostic,preventive and therapeutic measures for infectious complications.Still,Infections are a major concern in kidney transplant and is associated with increased morbidity and mortality,coupled with higher chronic graft dysfunction and graft loss.
Advances in diagnosis, prevention and therapy, incidence of infections has declined to 15-44% with mortality rate reduced to < 5% in developed countries. However, there is limited data on the etiology and course of post-transplant infections in developing countries.It is estimated that infections complicate the course of 50–70% of transplant recipients in developing countries,with high mortality.Very few studies are available regarding post-transplant infections in India.The spectrum of infections, their chronological occurrence, and the risk factors are different from that of developed regions.We studied timing of different infections, their presentation and outcome during first 12 months of renal transplantation at our Centre, Institute of Kidney Disease and Research Centre, Ahmedabad, India (IKDRC). This study helps to describe the clinical profile and presenting symptoms of patients developing infections, prevalence and time of occurrence of various infections within first 12 months after renal transplant. This study aims to determine the risk factors associated with occurrence of infections, the prevailing etiologic agents and their source of origin in Kidney transplant recipients.This study also helps in determine the influence of infections and their treatment on allograft function, morbidity and mortality.
Methods: We followed 430 patients (deceased donor or live related) who underwent kidney transplant at Institute of Kidney Diseases and Research Centre (IKDRC), Ahmedabad, India over a period of one year. All the patients were studied for a period of first 12 months after renal transplant for occurrence of infections, its management and course. Patients who developed infection after one year of their transplant were not included in the study.
Follow-up was weekly for first month, fortnightly till 3rd month and monthly till 12th months of transplant and also whenever a patient developed any complaints or symptoms of infection.They were analyzed for type of induction agents and immunosuppressant drugs, number of rejection episodes and residual graft dysfunction. Statistical analysis was performed using spss17 software. P value was calculated using Fisher’s exact t test and chi square test. P<0.05 was considered statistically significant.
Results: Total 131 KTR developed 154 episodes of infections; with overall prevalence rate of infection 35.8% during 1st year post transplant.Out of these, 35(22.7%) episodes occurred in 1st month, 70(45.4%) within 1-6th month and 49(31.8%) within 6 to12th month after transplant.In the 1st month of post-transplant, UTI was the commonest among all infections (65.7%), while pneumonia (all causes) was most common during 1st to 12th months. Bacterial agents were the commonest among all causes of infection in present study.
ATG was used as induction agent in 97(74%) KTR and basiliximab in 34 (26.0%) KTR. Out of 299 KTR without infections, ATG was used in 174(58.15%) and basiliximab in 125 (41.8%) KTR. Use of ATG was significantly associated with development of infection as compared to injection basiliximab. (P=0.0017).Rejection before infection occurred in 23(17.5%) KTR, while in 30(10.01%) KTR there was no infection after rejection. Occurrence of rejection was significantly associated with the development of infection episodes subsequently as compared to no rejection group (P=0.03).
Out of 131 KTR with infection, 73(55.7%) had HLA<3 while 58(44.3%) had HLA≥3. Out of 299 KTR without infections, 104(34.8%) had HLA<3 and 195 (65.2%) had HLA ≥3. The data indicate that there is significant increase chance of infection (p=.001) with <3 HLA match as compare to more than 3 HLA match. Delayed graft function (DGF) was present in 14(10.6%) cases and in patients without any infection, DGF was present in 38(12.7%).DGF was not significantly associated with infection episode as compared to no DGF group (P=0.5).
In present study, out of a total of 131 patients developing infections, 117 patients survived (survival rate-89.3%). During infection, 14(10.7%) patients expired, Out of which 3(2.29%) expired during 1st month, 6 (4.58%) expired during 1-6 month and 5(3.81%) during 6-12 month.
Graft dysfunction developed in 83(63.4%) KTR during infection episodes, out of which 57 (43.5%) recovered fully and residual graft dysfunction persisted in 10 (7.6 %) with dialysis dependency in 2 patients.
Conclusion: In conclusion, occurrence of infections following renal transplant is a common complication. Post renal transplant infection significantly increases morbidity and mortality among KTR.
Use of ATG was significantly associated with development of infection. Graft rejection increases the risk of infection after anti-rejection therapy significantly. At our center there was no significant difference in occurrence of infection among live related and deceased donor transplantation. Other factor which is not associated with infection risk is Delayed Graft dysfunction. Poor HLA match increases chance of getting infection .This inference is difficult to accept because of small number of patients in study period which could be affected by many others medical and social factors affecting causes of infection.