Background: Polyomavirus BK virus infection is a significant complication of renal transplantation and is an important cause of allograft loss. Today, despite the innovations in the pharmaceutical industry, a curative treatment against the BK virus has not been developed. The management is not standardized and is generally based on reported experience from transplantation centers. However, the literature on the subject with large samples is limited. Therefore, we designed a study to present our countrywide experience with BK virus nephropathy (BKVN) in renal transplant recipients. Methods: Our study was conducted with thirty kidney transplant centers from all provinces of Turkey. Only cases with BKVN proven by allograft biopsy were included in our study. Demographic characteristics and laboratory values of the patients were obtained from the archives and electronic databases of the centers. Results: A total of 13.857 patients from 30 transplantation centers were screened. 207 BKVN cases proven by allograft biopsy were identified and included in the study. The mean age was 46.4±13.1, and 146 (70.5%) patients were male. Twenty-six patients did not receive any induction therapy, 144 patients received anti-T lymphocyte globulin (ATLG), and 37 patients received basiliximab after transplantation. 23.6% of the patients had acute rejection history in the first six months of renal transplantation. all were treated with pulse steroids, and 46 were also treated with ATLG. The mean time to diagnosis of BKVN was 15.8±22.2 months after transplantation. At the time of diagnosis, the patients’ mean creatinine level was 1.8±0.7 mg/dl, and the mean estimated glomerular filtration rate was 45.8±19.6 ml/min. While BKVN was solely reported in 181 cases, there were cellular rejection findings in 21 biopsy specimens and humoral rejection in 4 biopsy specimens. In addition of dose reduction or discontinuation of immunosuppressive drugs, eighteen patients were treated with cidofovir, 11 patients with leflunomide, 17 patients with quinolones, 15 patients with intravenous immunoglobulin (IVIG), five patients with cidofovir+IVIG, and 12 patients with leflunomide+IVIG. None of the patients who received leflunomide and leflunomide+IVIG had allograft loss. Allograft loss was observed in 12 (15%) of 78 patients treated with antivirals or immunomodulators. Allograft loss occurred in 32 patients (15%) during follow-up out of 207 patients with BKVN. Five patients were retransplanted, and none developed BKVN during the follow-up. Conclusions: BKVN is still a significant cause of allograft loss in kidney transplantation, which has not been fully elucidated. Leflunomide appears to be an effective treatment in these patients.

Aim: Kidney transplant patients are amongst the high-risk groups for severe Covid 19. To date, no specific antiviral agent has been found uniformly effective against severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). Favipiravir, the recommended drug by The Turkish Ministry of Health, was uniformly supplied to all patients diagnosed to have COVID 19 with a positive nasopharyngeal swap PCR test. The aim of our study was to retrospectively compare our kidney transplant recipients who developed COVID-19 infection started on Favipiravir to those who did not use Favipiravir for the clinical course of the disease with a special emphasis on the occurrence of side effects/adverse events. Methods: Thirty-seven consecutive KT recipients with a median age of 46 years and of whom 62.2% were women; 8 deceased /29 living related donor, with a 8.0 (5.5-12.5) years median duration of transplantation were included in the study. Results: Twenty-six (70.3%) patients received Favipiravir, 11(29.7%) did not. There was no statistical significance in baseline demographic, clinical and laboratory findings between the groups except that the Favipiravir group was older and had a higher requirement of oxygen treatment. There was no statistically significant difference in the course and outcome of COVID-19 infection, in the occurrence of side effects/adverse events related to Favipiravir between the two groups. Laboratory data at baseline, day7 and 30 were also comparable between the groups. Conclusion: Although the efficacy of Favipiravir in the treatment of COVID-19 infection is currently controversial, Favipiravir can safely be used in kidney transplant patients.

Purpose: Kidney transplant recipients are prone to metabolic bone diseases and consequent fractures. This study aimed to evaluate the incidence of incipient vertebral fractures, osteopenia, osteoporosis, and the clinical factors associated with incipient vertebral fractures in a group of kidney transplant patients. Methods: Two hundred sixty-four patients (F/M:124/140, 45.3±13 years) who had undergone kidney transplantation between 2008 and 2018 and who were followed up at least one year in third care centers were included in this multicenter retrospective study. Bone mineral densitometry was performed using dual-energy X-ray absorptiometry. Vertebral fractures were assessed semi-quantitatively using conventional thoracolumbar lateral radiography in 202 of the patients. Results: Vertebral fractures were observed in 56.4% (n=114) of the study group. Severe vertebral fractures were observed in 30.7% (n=62) of the patients in vertebral X-ray evaluation. The frequency of osteoporosis was 20.0% (53 of 264 patients), and osteopenia was 35.6% (94 of 264 patients). BMD levels were in the normal range in 40.3% (n=46) of the subjects with vertebral fractures. It was in the osteoporotic range in 20.1% (n=23) and the osteopenic range in 40.3% (n=46). Serum calcium, parathormone vitamin, and creatinine levels were similar between the patients with and without vertebral fractures. Femoral neck BMD was negatively correlated with age (r: −0.21, p<0.001) and positively correlated with body mass index (r:0.29, p<0.001). Vertebral fractures were associated with age, duration of hemodialysis, BMI, femoral neck Z score (R2: 37.8%, p=0.027). Conclusion: BMD was in the normal or osteopenic range in 79.8% in our cohort of renal transplant patients with incipient vertebral fractures. As incipient vertebral fractures can be observed in patients with normal BMD levels in kidney transplant recipients, conventional X-ray screening for vertebral fractures may be beneficial for a proper therapy decision of metabolic bone disease in kidney transplant recipients.

Background: The most common infections among renal transplant patients are urinary tract infections (UTI). Our main objective in this study is to determine the incidence of UTIs in patients who have undergone renal transplantation in our hospital, to identify the causative microbiological agents, risk factors and determine the effects of UTI on short-term graft survival. Methods: Adult patients, who underwent renal transplantation between October 2011 and July 2018, were included in this study. Urinary tract infections which developed within the first year of renal transplantation were investigated. Patients were compared regarding demographic, clinical, laboratory characteristics, and graft survival. Results: 102 patients were included in our study. Forty patients (51.9%) were male and 37 (48.1%) were female. Sixty-seven urinary tract infection attacks in 21 patients were recorded. Age (p=0.009; 95% Confidence Interval [CI]: 1.014-1.105), longer indwelling urinary catheter stay time (p=0.027; 95% Confidence Interval [CI]: 1.010-1.174) and urologic complications (p=0.032; 95% Confidence Interval [CI]: 0.094-0.896) were found as risk factors for UTI development in the first year of transplantation. Escherichia coli and Klebsiella pneumoniae were the most frequently isolated microorganisms. Of these bacteria, 63.2 % were found to be extended spectrum beta lactamase (ESBL) positive. Resistant microorganisms were more frequent in male patients (31 episodes in males vs. 12 episodes in females, p=0.0015). UTI had no negative impact on short-term graft survival. Conclusion: Patients with advanced age, who had a longer duration of bladder catheterization and urologic complications should be followed carefully regarding UTI. Since there is a high incidence of UTI in male transplant patients, more frequently caused by resistant microorganisms, infection control methods should be applied more vigorously especially in male transplant patients.