Urinary Tract Infection and Their Risk Factors Association in Renal Transplant Recipients

Background: Urinary tract infection (UTI) remains one of the most common and major complications after renal transplantation. Objective: The study was undertaken to get an insight regar{ing t}re bacterial pathogen which is responsible for UTI in post renal transplant patients and their risk factors association. Methods: This was an observational study, conducted in the Department of Microbiology and Immunology Bangabandhu Sheikh Mujib Medical University (BSMMU) from December 2010 to December 2011. Twentyone renal transplant recipients were evaluated for UTI after surgery up to six weeks. Microscopic examination and culture of urine were performed in every pretransplant period, 3rd POD, 7th POD, within six weeks and as per patient's clinical condition. UTI was considered when bacterial count was ) 103 per ml of urine along with pus cell count of >5 / HPF. Analysis was doneby using SPSS ver. 20.0.The level of significance was taken as 0.05. Student's t test and chi square test were done to compare the variables in UTI and non UTI patients. Result: Total 69 urine specimens were taken from 21 post renal transplant recipients in different periods. Thirteen (61.90Vo) patients developed UTI during the initial post ffansplant period. Among the 69 urine specimens, 22 (3I.88Vo) yielded positive results for culture in which Enterococcus spp. (507o) was the major pathogen isolated. Prolonged urinary catheterization, post operation hospital stay and duration of dialysis were statistically significant risk factors leading to UTI in post renal transplant recipients. Conclusion: Enterococcus spp. is an emerging pathogen responsible for UTI. Prolonged period ofcatheterization, post operation hospital stay and duration ofdialysis are the risk factors for UTI in post renal transplant recipients.


Introduction:
Urinary tractinfections (UTI) are the most common infec- tious complications in patients receiving renal transplant for end stage kidney disease '.UTI is associated with the development of impaired allograft function, allograft loss, and deathz.Urinary tract infection compromises approximately 45 to 47 percent of infectious complications of renal transplantation3.
In BSMMU, Dhaka were Pseudomonas 06 (09Vo), Kleb- siella 05 (087o), Staphylococcus 03 (4.57o) and Entero- coccus 01 (I.57o) Iqbal et als reported about the risk factors, of UTI in post transplant patients including prolonged period of catheterrzatron, prolonged hospital stay, prolonged period of hemodialysis, stent placement was not found to be a significant risk factor 5'10 It is advisable to caffy out urinary culture on kidney trans- plant patients within first few months, because of their extreme vulnerability to UTI.Furthennore, urinary culture gives the opportunity of performing an antibio- gram, which c,&n lead to appropriate medical treatment6.
The incidence of UTI following transplantation has decreased because of improvements in surgical proce- dure, rapid removal of the urethral catheter, refinement of immunosuppressive therapy, and routine administration of antibiotic therapyll.
So early detection of UTI and its risk factors in post renal transplant patients is needed for the management and treatment of post renal complication.Therefore for designing a control program of post renal transplant infection the present study was carried out to identify the 130 etiologic agents and risk factors of UTI in post renal transplant patients in BSMMU that will help to increase the chance of graftr survival.

Methods:
This was an observational study carned out in the Department of Microbiology and Immunology, BSMMU, Shah- bagh, Dhaka, Bangladesh from December 20LO to December z}ll.Institutional review board (IRB) was approved the study to conduct (No.BSMMU/201115465, Date: 2l-05-201I).Informed written consent was taken from the patients.A total 21 post renal transplantpatients from the Department of Nephrology, BSMMU were evaluated for urinary ffact infection and their risk factors association.Among the enrolled patients 17 were male & 3 were female.A Foley catheter was introduced before surgery &, it remains from 5-10 days afterwards.Urine specimens were taken from each patient in preoperative period for screening & directly from the catheter on 3rd, 7th post operative day & within six weeks.
Urinary studies: At first the catheter collection port was disinfected with 70Vo alcohol, and then catheter was clamped below the port and allows the urine to collect in tube for 1O-20 minutes.After that with the help of sterile syringe 5-10 ml of urine was collected in a sterile leak proof container and then transported to the Department of Microbiology and Immunology BSMMU.Microscopic urinary sediment examinations were done after centrifugation of the sample at 1000 g for 15 minutes on a clinical centrifuge 4. Urinary quantitative culture was done on Chromo agff media and incubated at 37 0c for 24 hours.It was considered a positive result for urinary tract infection (UTI) when bacterial counts were recorded up to 103 or more per ml of urine and a WBC count of >5 / HPF12.Isolated Gram negative and Gram positive organisms were identified by standard phenotypic detection meth- ods.Data regarding duration of dialysis, number of days of Foley's catheter was retained and post operative hospital stay was entered in Statistical Package for Social Sciences Version 20.0.Student's t test and chi square test Urinary Tract Infection Ald Their Risk Factors Association In Renal Transplmt Rrcipients.
Rehana Ruak Khan et al were performed to analyze the data.A Significant p value was considered less than 0.05.

Table-I
Organisms causing urinary tract infection in renal transplant recipients (n-22 ) Microorganism N(%) On7 days and onwards of cathetenzatron UTI was found in ll(84.6L7o).Less than 7 days cathetenzation UTI developed rn2(15.387o)Table-II).Among UTI patients mean duration of dialysis (p= 0.003), delay in removal of Foley's catheter (p=0.002) and post transplant hospital stay (p= 0.001) were found statistically significant risk factors for leading to UTI in renal trans- plant patients of BSMMU (Table-Ilf .

Table -III
Comparison of characteristics of risk factors of urinary tract infection and non urinary tract infection groups in post transplant patients (n-21 ) Parameters UTI (n=13) Non-UTI P value (n=08) Among the 2I renal transplant recipients 0l(4.547o)patients developed UTI in 3rd POD and 5th POD, 08(38.09Vo)patients in 7th POD & 09(42.85%o)patients within 6th weeks after transplantation (Fig -l).

8.09
Durationof  Dialysis (months) Mean duration 7+ 2 of Foleys catheter (days) Post-op. UTeveloped in most of the patients (61.90Vo) within 6'h weeks of renal transplantation which was seen in present study.This finding was in consistent with the findings of the study by IslamT in BSMMU. He tudied 3l patients, over a period of 2 years and found 79Vo UTI in these patten{.Iqbal et als tn 2010 reported UTI in'777o patients out of 66 renal transplant recipients within 8 weeks of post renal transplant period.Findings of these studies were similar to our observation.UTI in post renal transplant patients are probably due to use of immunosuppressive drugs, urinary catheterization and increased post transplant hospital stay.
In the present study, major pathogen responsible for UTI was Enterococcus spp.(507o).These observations are also correlate with the data of the study by Mathe et all0 who reported Enterococcus spp. as the leading uropatho- gen causing UTI after renal transplantation.Schies zer et all3 reported in 2008 that, Gram positive organism accounts about 407o of uropathogen for renal transplant population.Among the gram positive organisffis, the predominant pathogen in their studies appear to be Enterococcus spp.Sanchez et ala in their study found Enterococcus spp (477o) to be the major bacterial pathogen of UTI in post renal transplant and they have reported Enterococcus spp. as an emerging bacterium responsible for symptomatic infections in kidney transpl ant patients.
In this study, other pathogen besides Enterococcus spp.
Another study in Pakistan by Iqbal et a15 found E. coli (517o) to be the predominant organism in UTI followed by Pseudomonas aeruginosa, Klebsiella spp.Morganella morgani, Enterobacter spp., Enterococcus.spp .MRSA.
This study showed that, out of 13 UTI patients, 10 patients developed UTI within 7'h POD and 9 patients developed UTI between 10th POD till 6 weeks after renal transplan- Regarding the risk factors, the findings of this study showed that 11 (84.61)patients who had longer duration of catheterrzation (>1 days) developed urinary tract infection out of 13 UTI patients.This findings was consistent with Islam7 study who have reported that 13 (54.L6%o) out of 24 post renal transplant patients had developed UTI who have more than 7 days cathetenzation Schaeffer et aI16 reported that, longer period of urethral catheterrzati.on may cause greater harm to the nofinal flora and may lead to a higher incidence of urinary infection.Rubinl7 also showed, when the urethral catheters are removed within l-4 days of the renal transplant, the development of infection is unusual.
It was observed from this observational study that, prolonged Foley's cathetertzatron and post transplant hospitalizatron were found to be increased risk for leading to UTI.These finding also consistent with study by Iqbal  tation.There is slight increase in the rate of development of UTI in each day a bladder catheter is left in place, prolonged duration of dialysis, increased post transplant hospitalization So early removal of urethral catheter and discharge of patients as early as possible is recommended.

Conclusion:
Most of post renal transplant recipients (6L.907o.)devel- oped UTI in early post transplant periods.Enterococcus spp.(507o) was the major pathogen causing UTI in transplant patients.Risk factors associated with UTI were prolonged urinary cathetenzation, prolonged period of dialysis and prolonged period of post transplant hospitalizatton.
Fig-l: Number of urine transplant periods (3rd, weeks) n-I3 et als rn2010 and Dantas et a118 rn2006 demonstrated that the length of hospitalization was related to the infection in post renal transplant patients.
From above discussion we can see that most of the patients suffered from UTI in early weeks after transplan- t32 Rehma Rzzak Khan et al Urinary Tract Infection And Their Risk Factors Association In Renal Trmsplmt Recipients.

Table - II
Duration of catheter associated with UTI in post renal transplant patients (n-13 ).Chi square test was done to measure the level of signifi- *cance.
tation.Oliveira et ells in 2001 reported highest number of UTI on 4th POD.But we could not compare our results with the study done by Oliveira et al as catheters was removed from these patients after 4'h POD15.