M. D'Angelo

Incidence of Urinary Tract Infections Caused by Germs Resistant to Antibiotics Commonly Used After Renal Transplantation

BACKGROUND The inadequate utilization of antibiotics is responsible for the development of urinary tract infections (UTI) after renal transplantation (RT), through the induction of resistance to the antibiotics themselves. The purpose of this study was to evaluate the incidence of resistance to cefotaxime (CEF) and trimethoprim/sulfamethoxazole (TMP-SMX), routinely used for surgical perioperative prophylaxis and prevention of Pneumocystis carinii, respectively. MATERIALS AND METHODS We enrolled all adult patients having received an RT from 2001 to 2006 and having a minimum follow-up of 6 months. Urine cultures (UC) were routinely performed at every outpatient clinic control and whenever required by the onset of significant clinical signs/symptoms. UTI was diagnosed by the presence of a positive UC. The endpoint of the study was the emergence of bacterial strains resistant to either CEF or TMP/SMX. RESULTS We recorded 169 UTI in 76 patients (38 men/38 women, 33%) over a mean follow-up of 779.9+/-523.3 days. Thirty-nine patients (51%) developed more than 1 UTI episode. When gram-negative bacteria were considered, 102/144 (70.8%) tests showed resistance to TMP/SMX, while data were available in about only 7 gram-positive infections (5/7, 71%). CEF was tested less frequently with 21/43 (49%) germs resistant to this molecule. CONCLUSIONS The onset of bacterial resistance to either TMP/SMX or CEF is frequent after RT. A wiser stricter utilization of antibiotics is mandatory. Standard antibiotic protocols should be revised.

Fatal hemorrhage in two renal graft recipients with multi-drug resistant Pseudomonas aeruginosa infection.

Abstract: Pseudomonas aeruginosa (PA) infections occurring after renal transplantation (RT) represent a potentially life‐threatening complication. We present 2 cases of early death following RT in which PA was transmitted, possibly from the donor to the recipients, despite preoperative cultures that were negative. The donor had developed PA‐related bilateral pneumonia while in the intensive care unit. However, after appropriate antibiotic therapy, no signs of infection were present at the time of organ retrieval and cultures were negative. Both recipients received a renal graft from the same donor and developed multi‐drug resistant (MDR)‐PA infections with bacterial phenotypes and resistances similar to the donor. The first recipient died 9 days after RT from rupture of a false aneurysm of the external iliac artery, caused by a fully thickened PA‐related arteritis. The second recipient died postoperatively on day 10 after rupture of an aneurysm in the right vertebral artery. Our experience shows that MDR‐PA infection early after RT may be a catastrophic event. Specific anti‐PA antibiotic therapy in RT patients during the perioperative period is recommended in the case of PA infection in the donor, even after apparent successful therapy with negative cultures.

A Systematic Review of Two Different Trimetoprim–Sulfamethoxazole Regimens Used to Prevent Pneumocystis jirovecii and No Prophylaxis at All in Transplant Recipients: Appraising the Evidence

BACKGROUND The aim of this study was to clarify the potential advantages of a low-dose regimen of trimethoprim-sulfamethoxazole prophylaxis to prevent Pneumocystis jirovecii pneumonia (PJP) in transplant recipients (80/400 mg/d every day or 160/800 mg/d every other day) with those obtained from the full-dose prophylaxis (160/800 mg/d every day) or no prophylaxis. METHODS Prospectively randomized and retrospectively case controlled studies were selected. RESULTS Four studies matched the inclusion criteria-2 randomized and 2 case controls-for a total of 570 patients. The pneumonia incidence was 0% after full-dose prophylaxis (0/181), 1% after the low-dose regimen (1/105), and 11% with no prophylaxis (31/284). Pneumonia occurrences were significant lower between the full-dose prophylaxis versus the no prophylaxis group (0% vs 11%; P < .001), and between the low-dose and no prophylaxis groups (1% vs 11%; P < .001). There was no difference between patients receiving the full-dose prophylaxis versus the low-dose regimen (0% vs 1%; P = NS). CONCLUSIONS The low-dose gives similar results as the full-dose regimen for the prevention of PJP and seems a feasible, safe option for transplanted patients.

De Novo Autoimmune Hepatitis Following Liver Transplantation : A Case Report

De novo autoimmune hepatitis (AIH), a rare disorder first described in 1998, appears in patients with liver transplants due to autoimmune and nonautoimmune etiologies. De novo AIH occurs in 2.5% to 3.4% of allografts; children seem to have a predilection for this syndrome. We have present herein a case of a liver allograft recipient who developed chronic hepatitis associated with autoimmune features outlining the clinical course, liver histology, and response to treatment.

Regenerative Medicine Applied to Solid Organ Transplantation: Where Do We Stand?

The objective of regenerative medicine (RM) and Tissue Engineering (TE) is to create living functional tissues to repair or replace tissues or organ functions. This field holds the promise of regenerating damaged tissues and organs in the body. It has the potential to solve the problems of organ shortage and of toxicities deriving from life-long immunosuppression. In fact, cells in the regenerated organ would match those of the patient, from whom they would normally be derived. In the past decade, RM/TE has achieved striking results which are of interest to the transplant community. However, major roadblocks on the avenue to full success include the need for a deeper understanding of cell biology and of interactions with the extracellular matrix. We are presently not able to grow and expand cells indefinitely and safely in various scenarios where RM/TE may be indicated. The production of adequately vascularized scaffolds to optimize nutrients and oxygen delivery, assessment of the viability and function of the cells in the bioengineered construct, and the costs remain areas of scientific research.

Clinical Operational Tolerance After Kidney Transplantation: A Short Literature Review

The clinical era of solid organ transplantation started with a renal transplantation (RT) performed between identical twins in Boston in 1954. The patient did not receive any immunosuppression, thus representing the very first case of operational tolerance (Tol). However, more than half a century later, we must admit the inadequacy of our knowledge regarding such a fundamental aspect of transplant immunology, as demonstrated by the fact that Tol has never been achieved in an intention-to-treat protocol. Herein we aim to shortly review the worldwide experience on clinical operational Tol after RT. Thus far, reports on successful cases of Tol after RT have been anecdotal: the largest series included no more than 10 individuals. We will understand that Tol can develop even in the presence of either HLA mismatches or blood group incompatibility at baseline, in the presence of anti-HLA antibodies during follow-up, as well as in patients having experienced acute rejection. Despite the lack of robust evidence, the fact that Tol is often accidentally discovered by transplant physicians during follow-up in noncompliant patients justifies the hypothesis that the real number of Tol cases might be much higher than currently reported.

Clinical Operational Tolerance After Solid Organ Transplantation

Clinical operational tolerance (COT) is a clinical condition obtainable with difficulty after solid organ transplantation (SOT). It is characterized by perfectly normal graft function in the total absence of maintenance immunosuppression. Major benefits deriving from the onset of COT are the reduction of risk for immunosuppression-related side effects and the improved quality of life. Currently, COT can be safely achieved in stable liver transplant recipients; it remains a challenge after renal transplantation. Only 1 case of COT has been reported after lung transplantation; no cases have been described after other types of SOT. Overall, mechanisms of COT are unclear and strategies to induce COT cannot be applied on a regular base to a large cohort of SOT recipients. Due to the failure of molecularly based tolerogenic protocols, great hope relies in the adoption of cell-based strategies.

A Rare Case of Herpes Simplex Type 1 Bronchopneumonia Associated With Cardiomegaly in Renal Transplantation

INTRODUCTION We report a rare case of herpes simplex virus (HSV) type 1B in patient with kidney transplant as a possible cause of patient death. CASE REPORT A 32-year-old renal transplanted Caucasian man was referred for asthenia, fever, anemia, chest pain, cough, dyspnea, myalgias, peripheral edema, acute renal failure, diffuse cutaneus and mucous vesicles, and acute weight gain. The home therapy consisted of tacrolimus, sodic mycophenolate, and steroids. Laboratory data, bronchoscopy, and bronchial mucosal biopsy revealed HSV1B. We administered antiviral and antibiotic agents and reduced tacrolimus with clinical resolution. But after 10 days from discharge, the patient was admitted for acute cardiomegaly. So using ex adiuvantibus criteria we administered antiviral therapy with complete clinical improvement. CONCLUSION According to the literature, posttransplant HSV1B infection is a rare but severe complication of kidney transplantation associated with poor graft survival and a high mortality. Only an early, accurate diagnosis with efficient treatment permitted resolution of the problem. Our report stresses the difficulty of HSV2B clinical diagnosis and treatment.

Surgical Antibiotic Prophylaxis After Renal Transplantation: Time to Reconsider

The optimal regimen for perioperative antibiotic prophylaxis after renal transplantation remains to be determined. Worldwide, it seems there is a trend toward decreased use of prophylaxis from the first 48 hours to several days after surgery. However, bacterial strains resistant to common antibiotic agents arise even if only a single dose of a molecule is administered at any time. Inasmuch as infections currently are the primary cause of hospitalization after renal transplantation, it is desirable to not favor selection of resistant strains that may not be treated appropriately in the event of onset of infection. Therefore, antibiotic therapy, whether for therapeutic or prophylactic purposes, should be administered based exclusively on clinical evidence. Because systemic antibiotic prophylaxis is not effective against infections of the urinary tract, the objective of perioperative antibiotic prophylaxis should be to prevent infection of the surgical wound. In this case, administration of a single dose of an antibiotic agent (1-shot regimen) at the induction of anesthesia is effective and safe. For these reasons, it is urgent that new guidelines be defined for perioperative antibiotic prophylaxis. Multicenter prospective randomized trials comparing 1-shot vs multiple-dose regimens should be performed to establish the optimal regimen.

Scrotal Herniation of the Ureter: A Rare Late Complication After Renal Transplantation

Although late ureteral obstruction represents the most frequent urologic complication after renal transplantation, its etiology remains poorly understood. Benign prostatic hyperplasia (BPH) is the most common cause of urinary tract obstruction in the adult male population, but information regarding BPH epidemiology and its impact on clinical outcomes are lacking. We herein have described a case of ureteral herniation into the scrotum, secondary to concomitant upper and lower urinary tract obstruction: namely, BPH and ureterovesical junction stenosis causing massive urine retention and acute renal failure. The simultaneous presence of the 2 lesions rendered the diagnosis difficult. In addition, urine outflow responsible for bladder outlet obstruction resumed after transurethral resection of the prostate (TURP). The hydroureteronephrosis, which persisted after the TURP resolved only after positioning a double J stent, but renal function did not normalize. Attention must be paid to BPH in the differential diagnosis of urinary tract obstruction. Stenosis of the ureterovesical junction may occur very late after transplantation.