Lymphocele after pediatric kidney transplantation: incidence and risk factors.

Lymphocele is a well-known postoperative complication after kidney transplantation. The aim of this study was to analyze time trend incidence, risk factors, and outcome of post-transplant lymphocele in a large pediatric cohort. This is a retrospective single institution review of 241 pediatric kidney transplants performed from 2000 to 2013. Etiology of end-stage renal disease, recipient age and gender, transplant year, BMI percentile for age, type of dialysis, living/non-living related donor, acute rejection, and multiple transplantations were analyzed in association with lymphocele formation. Fourteen of 241 (5.81%) children developed a postoperative lymphocele. There has been a reduction in the incidence of lymphocele after 2006 (3.22% vs. 8.55%, p < 0.05). Significant risk factors for lymphocele were older age (≥11 yr), transplant before 2006, male gender, BMI percentile for age ≥95%, and multiple transplantations (p < 0.05). The one-yr graft survival was significantly reduced in the group with lymphocele compared with control (81.2% vs. 92.51%, p < 0.04). This is the first pediatric report showing the following risk factors associated with post-transplant lymphocele: age ≥11 yr, male gender, BMI for age ≥95%, and multiple transplantations. A lymphocele can contribute to graft loss in the first-year post-transplant.

Impact of severe neutropenia and other risk factors on early removal of implanted central venous catheter (ICVC) in children with hematologic malignancies.

BACKGROUND/PURPOSE: In neutropenic children with hematologic malignancies, the optimal timing of implanted central venous catheter (ICVC) insertion is unclear. The policy in our Institution has been to place ICVC at the time of diagnosis of disease regardless of the absolute neutrophil count. The impact of this strategy on the incidence of ICVC removal within 30 days of placement was evaluated in a series of patients. Other possible risk factors for ICVC early removal were also examined. MATERIALS AND METHODS: Records of all children with hematologic malignancies who underwent placement of ICVC during 2007 to 2010 were reviewed. The incidence of catheter-related complications and early removal was compared between subjects who were neutropenic at the time of ICVC placement and those who had a normal absolute neutrophil count. RESULTS: An ICVC was placed in 117 children, and only in 12 (10.2%) children it was removed within 30 days. However, the incidence of complications and removal was not influenced by the presence of neutropenia. Only an age below 2 years was demonstrated to be a risk factor for early complication and removal. CONCLUSIONS: The policy to place ICVC in neutropenic patients has been reasonably safe, in our hands. Meticulous preoperative evaluation, the accurate surgical technique and considerable care in their postoperative management are essential to prevent complications, especially in newborns and infants, who seem to be at greater risk of ICVC removal.

The surgical approach for cervicothoracic masses in children.

BACKGROUND: The surgical approach to masses located in the cervicothoracic juncton represents a challenge for surgeons. Many techniques have been described with good results. METHODS: We analyzed and compared the results obtained in 2 Italian pediatric surgery centers using 2 different techniques in patients with tumors of the thoracic inlet: center 1, using anterior cervical transsternal approach on 7 patients, and center 2, applying "trap-door" technique on 5 patients. RESULTS: Excision was incomplete in 5 patients and complete in 7 patients. Histologic examination revealed 5 patients with neuroblastoma; 3, ganglioneuroblastoma; 1, mixoid liposarcoma; 1, desmoid fibromatosis; 1, Castleman disease; and 1, Schwann cell tumor. The median duration of the procedure was 345 minutes in center 1 and 245 minutes in center 2. The median blood loss was 200 mL in both centers. The median hospital stay was 11 days in center 1 and 9 days in center 2. Globally, 5 patients developed postoperative complications. No significant differences were encountered comparing the main surgical outcome parameters between the 2 approaches. CONCLUSIONS: Both techniques resulted in valid options to achieve a safe excision of thoracic inlet masses with a manageable complication rate and acceptable hospital stay. Surgical risk factors should be carefully investigated preoperatively. Postoperative pain control is important to guarantee early recovery.

Human amniotic fluid-derived stem cells are rejected after transplantation in the myocardium of normal, ischemic, immuno-suppressed or immuno-deficient rat.

Human amniotic fluid-derived stem (AFS) cells, similarly to embryonic stem cells, could possess privileged immunological characteristics suitable for a successful transplantation even in a discordant xenograft system. We investigated whether AFS cells could be fruitfully used in a rat model of myocardial infarction. c-kit immunomagnetic-sorted AFS cells were characterized by flow cytometric analysis and cytospins as well as reverse-transcription polymerase chain reaction, Western blotting and immunocytochemistry for cardiovascular differentiation markers. In vitro, AFS cell phenotypic conversion was assayed by cardiovascular-specific induction media or co-cultured with rat neonatal cardiomyocytes. AFS cells showed mRNAs and/or protein for endothelial (angiopoietin, CD146) and smooth muscle (smoothelin) cells, and cardiomyocyte (Nkx2.5, MLC-2v, GATA-4, beta-MyHC) markers. Acquisition of a cardiomyocyte-like phenotype in rare AFS cells could be seen only in co-cultures with rat neonatal cells. In vivo, AFS cells xenotransplantated in a rat model of myocardial infarction, with or without cyclosporine treatment, or in intact heart from immuno-competent or immuno-deficient animals were acutely rejected due to the different recruitment of recipient CD4(+), CD8(+) T and B lymphocytes, NK cells and macrophages. This reaction is most likely to be linked to expression of B7 co-stimulatory molecules CD80 and CD86 as well as macrophage marker CD68 on AFS cells. Xenotransplanted AFS cells gave also rise in some animals to cell masses in the subendocardium and myocardium suggestive of a process of chondro-osteogenic differentiation. Despite AFS cells in vitro can differentiate to some extent to cells of cardiovascular lineages, their in vivo use in xenotransplantation for cell therapy of myocardial infarction is hampered by their peculiar immunogenic properties and phenotypic instability.

Cadaver kidney transplantation and vascular anomalies: a pediatric experience.

BACKGROUND: The incidence of donor kidneys with vascular anomalies ranges from 18% to 30%; such kidneys are usually at increased risk of vascular and urological complications. The aim of this study was to determine whether the use of cadaver kidneys with vascular anomalies would adversely affect posttransplant graft and patient outcome. METHODS: From October 1987 to January 2004, 241 patients underwent kidney transplantation in our pediatric surgery department. Vascular anomalies were noted in 77/241 grafts (31.9%); 50 (64.9%) had multiple renal arteries and 22 (28.5%) venous anomalies. Patients were divided into three groups: Group A (1 renal artery and vein, 1 arterial and venous anastomosis [n = 161]), Group B (> 1 renal artery or vein, 1 arterial and venous anastomosis [n = 33]), and Group C (> 1 renal artery or vein, > 1 arterial and venous anastomosis [n = 47]). We compared the three groups for: patient and graft survival, incidence of posttransplant acute tubular necrosis, vascular and urological complications, postoperative mean creatinine levels, and posttransplantation hypertension. RESULTS: We found no significant differences among the three groups regarding episodes of acute rejection or acute tubular necrosis. Creatinine levels reached normal levels within 30 days in all the groups without any significant differences. Furthermore, patient and graft survival were excellent (100% and 97%). CONCLUSIONS: The presence of vascular anomalies and their multiple or complex repair does not represent a theoretical disadvantage even in pediatric patients. In order to maximize the quantity and quality of donor kidneys especially in pediatric population, kidneys with vascular anomalies may be implanted with very little risk.

Renal transplantation in prune-belly syndrome.

We assess the effect of the prune-belly syndrome (PBS) on renal transplantation outcome. Six renal transplantations were performed in five boys affected by PBS (median age 5.8+/-2.1 years, median weight 13.6+/-2.4kg). Renal graft survival, graft function, lower urinary tract dysfunction, urinary tract infections (UTIs), associated complications and patients' survival after 1 and 5 years of follow-up were analysed. The rate for 1-5-year graft survival was 66.7% (mean serum creatinine 98-103 micromol/l). The surgical treatment of the documented bladder obstruction (two patients) and the severe abdominal wall deficit (one patient) led to a reduction of UTI: the patients maintained their native urinary tract and none received prophylactic antibiotics. The lack of abdominal wall musculature led to severe mechanical complication in one patient, but Monfort's abdominal wall reconstruction was able to restore the graft's function. The outcome of patients with PBS who undergo renal transplantation is good. Before the transplant, an accurate assessment of urinary tract anomalies and deficiency of the abdominal wall musculature is mandatory, to program the appropriate treatment and obtain a good long-term prognosis for the renal graft.

CMV and BKV ureteritis: which prognosis for the renal graft?

This report describes two cases of ureteral stricture in renal graft recipients related to cytomegalovirus (CMV) and human polyoma BK virus (BKV) ureteritis with the same onset characterized by acute graft failure with no clinical signs of systemic viral infections. The histological analysis did not show other causes of graft impairment (i.e. drug toxicity and acute rejection). Ultrasound scan (US) revealed absent or mild hydronephrosis. The diuretic-MAG3 renal scan showed a urinary flow obstruction. The viral genomes were isolated from urine, peripheral blood and graft or ureteral tissues samples. A percutaneous nephrostomy confirmed the stricture, but it restored urine flow only in the graft affected by CMV ureteritis, the association with a specific antiviral therapy probably produced a stable restoration of graft function. In BKV ureteritis,the graft prognosis was poor; graft loss could be due to the progress of BKV nephropathy. A correct differential diagnosis of the etiologic agent responsible for the ureteritis is mandatory, because treatment and outcome of the infection are different.