Serum C-reactive protein in pediatric kidney and liver transplant patients

Bacteremia in Pediatric Liver Transplant Recipients

BACKGROUND

We aimed to determine the frequency of bacteremia, septic shock and bacterial meningitis in pediatric liver transplant recipients (pLTRs) in the outpatient setting and to identify clinical factors associated with bacteremia.

METHODS

Multicenter retrospective study of pLTRs evaluated in the emergency department or outpatient clinic between 2010 and 2018 for suspected infection, defined as fever ≥38 °C or a blood culture obtained. We excluded patients with nontransplant immunodeficiency, multiorgan transplants or intestinal failure. The primary outcome was bacteremia; secondary outcomes included fluid-refractory septic shock, bacterial meningitis and antibiotic resistance. The unit of analysis was the encounter.

RESULTS

A total of 151 children had 336 encounters for infection evaluation within 2 years of transplant. Of 307 (91.4%) encounters with blood cultures, 17 (5.5%) had bacteremia, with 10 (58.8%) occurring within 3 months of transplant. Fluid-refractory septic shock and bacterial meningitis occurred in 7 out of 307 (2.8%) and 0 out of 307 encounters, respectively. Factors associated with bacteremia included closer proximity to transplant (<3 months) [odds ratio (OR): 3.6; 95% confidence interval (CI): 1.3-9.8; P = 0.01], shorter duration of illness (OR: 4.3; 95% CI: 1.5-12.0; P < 0.01) and the presence of a central venous catheter (CVC) (OR: 12.7; 95% CI: 4.4-36.6; P < 0.01). However, 5 (29.4%) encounters with bacteremia had none of these factors. Among Gram-positive pathogens, 1 out of 7 (14.2%) isolates were resistant to vancomycin. Among Gram-negative pathogens, 3 out of 13 (23.1%) isolates were resistant to 3rd generation cephalosporins.

CONCLUSIONS

Bacteremia was an important cause of infection within 2 years of pLTR. Clinical factors increased the risk of bacteremia. Further, large sample studies should derive multivariable models to identify those at high and low risk of bacteremia to optimize antibiotic use.

Use of C-Reactive Protein and Ferritin Biomarkers in Daily Pediatric Practice

Recent pediatric clinical research has begun to focus on risk stratification tools using multibiomarker models. C-reactive protein (CRP) and ferriti biomarkers are widely available and used to varying degrees in daily practice, but there is no single source examining the evidence behind their use.We set out to summarize the evidence behind the use of CRP and ferritin biomarkers in pediatric practice and to begin development of a consensus for their future use for pediatricians.All the literature involving CRP and ferritin in pediatrics available on PubMed was surveyed. Research applicable to daily pediatric practice was summarized in the body of the article. Pediatric clinicians of various subspecialties contributed to the summary of the use of CRP and ferritin biomarkers in clinical practice in various disease processes. A clinical decision pathway is described, and evidence is summarized.CRP and ferritin biomarkers have diverse uses with various cutoff values in the literature, making their use in daily practice difficult. Elevation of these markers coincides with their significant elevation in uncontrolled inflammation.CRP and ferritin biomarkers are widely used in pediatrics. This review provides a resource summarizing evidence into a single source. There is sufficient evidence to indicate that these biomarkers of inflammation can be useful in guiding clinical decision making in specific clinical scenarios; however, further work is needed to improve their use in clinical practice.

C-reactive protein at ICU admission as a marker of early graft dysfunction after liver transplant. A prospective, single-center cohort study

OBJECTIVE

To explore the behavior of C-reactive protein (CRP) after orthotopic liver transplantation (OLT) during the first postoperative days, and its usefulness as a marker of severe early allograft dysfunction (EAD).

DESIGN

A prospective, single-center cohort study was carried out.

SETTING

The Intensive Care Unit (ICU) of a regional hospital with a liver transplant program since 1997.

PATIENTS

The study comprised a total of 183 patients admitted to our ICU immediately after liver transplantation between 2009 and 2015.

VARIABLES OF INTEREST

C-reactive protein levels upon ICU admission and after 24 and 48h, severe EAD and hospital mortality.

RESULTS

The CRP levels after OLT were: upon ICU admission 57.5 (51.6-63.3)mg/L, after 24h 80.1 (72.9-87.3)mg/L and after 48h 69.9 (62.5-77.4)mg/L. Severe EAD patients (14.2%) had higher mortality (23.1 vs 2.5; OR 11.48: 2.98-44.19) and lower CRP upon ICU admission (39.3 [29.8-48.7]mg/L) than the patients without EAD (0.5 [53.9-67.0]; p<0.05] - the best cut-off point being 68mg/L (sensitivity 92.3%; specificity 40.1%; Youden index 0.33). Lower CRP upon ICU admission was correlated to higher mortality (24.5 [9.2-39.7] vs 59.4 [53.4-65.4]; p<0.01, AUC 0.79 [0.65-0.92]).

CONCLUSION

Liver transplant is a strong inflammatory stimulus accompanied by high levels of C-reactive protein. A blunted rise in CRP on the first postoperative day after OLT may be a marker of poor allograft function and is related to hospital mortality.

Role of C-reactive protein in the pathogenesis of acute kidney injury

Acute kidney injury (AKI) is characterized by both non-inflammatory and inflammatory process, and accumulating evidence has demonstrated that inflammation plays a key role in the pathogenesis and progression of AKI. C-reactive protein (CRP), an acute reactant produced by liver and many inflammatory cells, acts not only as an inflammation biomarker, but also as a pathogenic factor for AKI. Indeed, increased concentration of CRP is associated with poor outcome of varied etiologically related AKI patients. In recent years, the role of CRP is gradually recognized as an active participant in the pathogenesis and progression of AKI by exacerbating local inflammation, impairing the proliferation of damaged tubular epithelial cells and promoting fibrosis of injured renal tissue.

Procalcitonin for infections in the first week after pediatric liver transplantation

Background

Procalcitonin (PCT) has become a commonly used serum inflammatory marker. Our aim was to describe the kinetics and usefulness of serial post-operative PCT measurements to detect bacterial infection in a cohort of children immediately after pediatric liver transplantation (pLT).

Methods

We performed a retrospective chart review of a cohort of pLT recipients with serial serum PCT measurements in the first week following pLT. The presence of infection was determined on clinical and biological parameters. Normal PCT was defined as < 0.5 (ng/ml).

Results

Thirty-nine patients underwent 41 pLT. PCT was measured daily during the first week post pLT. Values first increased following surgery and then decreased, nearing 0.5 ng/ml at day seven. Peak PCT reached a median of 5.61 ng/ml (IQR 3.83-10.8). Seventeen patients were considered to have an infection. There was no significant difference in daily PCT or peak PCT between infected and non infected patients during the first post-operative week. AUC of ROC curve for PCT during first week was never higher than 0.6.

Conclusions

We conclude that serial PCT measurements during the first week after pLT is not useful to identify patients with bacterial infections. Rather, we propose that serum PCT may be useful after the first week post pLT.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2234-y) contains supplementary material, which is available to authorized users.

The 82-plex plasma protein signature that predicts increasing inflammation

The objective of the study was to define the specific plasma protein signature that predicts the increase of the inflammation marker C-reactive protein from index day to next-day using proteome analysis and novel bioinformatics tools. We performed a prospective study of 91 incident kidney transplant recipients and quantified 359 plasma proteins simultaneously using nano-Liquid-Chromatography-Tandem Mass-Spectrometry in individual samples and plasma C-reactive protein on the index day and the next day. Next-day C-reactive protein increased in 59 patients whereas it decreased in 32 patients. The prediction model selected and validated 82 plasma proteins which determined increased next-day C-reactive protein (area under receiver-operator-characteristics curve, 0.772; 95% confidence interval, 0.669 to 0.876; P < 0.0001). Multivariable logistic regression showed that 82-plex protein signature (P < 0.001) was associated with observed increased next-day C-reactive protein. The 82-plex protein signature outperformed routine clinical procedures. The category-free net reclassification index improved with 82-plex plasma protein signature (total net reclassification index, 88.3%). Using the 82-plex plasma protein signature increased net reclassification index with a clinical meaningful 10% increase of risk mainly by the improvement of reclassification of subjects in the event group. An 82-plex plasma protein signature predicts an increase of the inflammatory marker C-reactive protein.

Delta Neutrophil Index as a Marker for Differential Diagnosis between Acute Graft Pyelonephritis and Acute Graft Rejection

Introduction

The delta neutrophil index (DNI) is the fraction of circulating immature granulocytes, which reflect infectious and/or septic condition. Acute graft pyelonephritis (AGPN) versus acute graft rejection is a frequently encountered diagnostic and therapeutic dilemma in kidney transplant recipients, but little is known about the clinical usefulness of DNI value in the differentiation of the two conditions.

Material & Methods

A total of 90 episodes of AGPN or acute graft rejection were evaluated at the Kangdong Sacred Heart Hospital between 2008 and 2014. We performed retrospective analysis of demographic, clinical, and laboratory parameters data. Receiver operating curves (ROC) and multivariate logistic regression were conducted to ascertain the utility of DNI in discriminating between AGPN and acute graft rejection.

Results

AGPN group had significantly higher DNI values than acute graft rejection group (2.9% vs. 1.9%, P < 0.001). The area under the ROC curve for DNI value to discriminate between AGPN and acute graft rejection was 0.85 (95% confidence interval [CI]; 0.76–0.92, P < 0.001). A DNI value of 2.7% was selected as the cut-off value for AGPN, and kidney transplant recipients with a DNI value ≥ 2.7% were found to be at a higher risk of infection than those with a DNI < 2.7% (odd ratio [OR] 40.50; 95% CI 8.68–189.08; P < 0.001). In a multivariate logistic regression analysis, DNI was a significant independent factor for predicting AGPN after adjusting age, sex, log WBC count, log neutorphil count, log lymphocyte count, CRP concentration, and procalcitonin concentration (OR 4.32; 95% CI 1.81–10.34, P < 0.001).

Conclusions

This study showed that DNI was an effective marker to differentiate between AGPN and acute graft rejection. Thus, these finding suggest that DNI may be a useful marker in the management of these patients.

Systemic inflammation in xenograft recipients (SIXR): A new paradigm in pig-to-primate xenotransplantation?

Inflammation is a complex response that involves interactions between multiple proteins in the human body. The interaction between inflammation and coagulation is well-recognized, but its role in the dysregulation of coagulation in xenograft recipients is not well-understood. Additionally, inflammation is known to prevent the development of T cell tolerance after transplantation. Recent evidence indicates that systemic inflammation precedes and may be promoting activation of coagulation after pig-to-primate xenotransplantation. Activated recipient innate immune cells expressing tissue factor are increased after xenotransplantation, irrespective of immunosuppressive therapy. With immunosuppression, C-reactive protein (C-RP), fibrinogen, and interleukin-6 levels are significantly increased in pig artery patch recipients. In pig organ recipients, increased C-RP levels are observed prior to the development of features of consumptive coagulopathy. Systemic inflammation in xenograft recipients (Sixr) may be a key factor in the development of dysregulation of coagulation, as well as in resistance to immunosuppressive therapy. While genetic modification of the donor pigs provides protection against humoral responses and the development of thrombotic microangiopathy, therapeutic prevention of Sixr may be essential in order to prevent systemic dysregulation of coagulation in xenograft recipients without the use of intensive immunosuppression.

Febrile reaction associated with the infusion of haploidentical peripheral blood stem cells: incidence, clinical features, and risk factors

BACKGROUND

We reported febrile reaction after the infusion of haploidentical peripheral blood stem cells (PBSCs). The aim of this study was to better characterize this new clinical entity named by infusion-related febrile reaction (IRFR).

STUDY DESIGN AND METHODS

A retrospective analysis of 490 patients received allogeneic stem cell transplantation (SCT) between October 2009 and December 2011 at our institution.

RESULTS

The distribution of transplant type was 173 patients in HLA-identical siblings, 30 in unrelated, and 287 in haploidentical. IRFR was defined as unexplained fever of more than 38°C within 24 hours after the infusion of allogeneic PBSCs. We did not observe any IRFRs in patients undergoing HLA-identical sibling and unrelated transfusions. After excluding patients with a known source of infection, we classified haploidentical patients into IRFR and non-IRFR groups. Eighty-eight patients (30.7%) of 287 cases after the infusion of haploidentical PBSCs were diagnosed as IRFRs, chills in 3.5% (10/88), diarrhea in 21.6% (19/88), an erythematous skin rash in 0.3% (1/88), hypoxemia in 1.0% (3/88), and no other accompanying symptoms in 62.5% (55/88). Significantly higher elevation of C-reactive protein and complement C3 was seen in the IRFR group compared with the non-IRFR group. Multivariate analysis showed higher CD34+ dose was a significant predictor for IRFR (p = 0.023; hazard ratio = 1.848; 95% confidence interval, 1.087-3.142).

CONCLUSION

As a clinical feature belonging to haploidentical SCT, IRFR was associated with the higher numbers of CD34+ from PBSCs.

Systemic inflammation in xenograft recipients precedes activation of coagulation

BACKGROUND

Dysregulation of coagulation is considered a major barrier against successful pig organ xenotransplantation in non-human primates. Inflammation is known to promote activation of coagulation. The role of pro-inflammatory factors as well as the relationship between inflammation and activation of coagulation in xenograft recipients is poorly understood.

METHODS

Baboons received kidney (n=3), heart (n=4), or artery patch (n=8) xenografts from α1,3-galactosyltransferase gene-knockout (GTKO) pigs or GTKO pigs additionally transgenic for human complement-regulatory protein CD46 (GTKO/CD46). Immunosuppression (IS) was based on either CTLA4Ig or anti-CD154 costimulation blockade. Three artery patch recipients did not receive IS. Pro-inflammatory cytokines, chemokines, and coagulation parameters were evaluated in the circulation after transplantation. In artery patch recipients, monocytes and dendritic cells (DC) were monitored in peripheral blood. Expression of tissue factor (TF) and CD40 on monocytes and DC were assessed by flow cytometry. C-reactive protein (C-RP) levels in the blood and C-RP deposition in xenografts as well as native organs were evaluated. Baboon and pig C-RP mRNA in heart and kidney xenografts were evaluated.

RESULTS

In heart and kidney xenograft recipients, the levels of INFγ, TNF-α, IL-12, and IL-8 were not significantly higher after transplantation. However, MCP-1 and IL-6 levels were significantly higher after transplantation, particularly in kidney recipients. Elevated C-RP levels preceded activation of coagulation in heart and kidney recipients, where high levels of C-RP were maintained until the time of euthanasia in both heart and kidney recipients. In artery patch recipients, INFγ, TNF-α, IL-12, IL-8, and MCP-1 were elevated with no IS, while IL-6 was not. With IS, INFγ, TNF-α, IL-12, IL-8, and MCP-1 were reduced, but IL-6 was elevated. Elevated IL-6 levels were observed as early as 2 weeks in artery patch recipients. While IS was associated with reduced thrombin activation, fibrinogen and C-RP levels were increased when IS was given. There was a significant positive correlation between C-RP, IL-6, and fibrinogen levels. Additionally, absolute numbers of monocytes were significantly increased when IS was given, but not without IS. This was associated with increased CD40 and TF expression on CD14+ monocytes and lineage(neg) CD11c+ DC, with increased differentiation of the pro-inflammatory CD14+ CD11c+ monocyte population. At the time of euthanasia, C-RP deposition in kidney and heart xenografts, C-RP positive cells in artery patch xenograft and native lungs were detected. Finally, high levels of both pig and baboon C-RP mRNA were detected in heart and kidney xenografts.

CONCLUSIONS

Inflammatory responses precede activation of coagulation after organ xenotransplantation. Early upregulation of C-RP and IL-6 levels may amplify activation of coagulation through upregulation of TF on innate immune cells. Prevention of systemic inflammation in xenograft recipients (SIXR) may be required to prevent dysregulation of coagulation and avoid excessive IS after xenotransplantation.

Baseline evaluation of serum markers of inflammation and their utility in clinical practice in paediatric liver transplant recipients

BACKGROUND

Several biomarkers of penetrating infections vs. rejection in liver transplant (LT) have been suggested; however, baseline values in paediatric LT recipients have not been studied.

AIM

We evaluated the baseline concentration of procalcitonin (PCT), C-reactive protein (CRP) and interleukin-6 (IL-6) in a post-LT paediatric group.

METHODS

We measured serum PCT, CRP and IL-6 in 58 consecutive paediatric LT recipients. Specimens were collected for group 1 (n=22) at day 1, group 2 (n=12) at day 7 post-LT and group 3 (n=24) at onset of febrile episode. Day 7 samples were obtained from patients who had no graft dysfunction or signs/symptoms of sepsis.

RESULTS

Median values for PCT were: group 1 was 5.16 μg/L (95% CI, 2.18-21.13); group 2: 0.170 μg/L (95% CI, 0.15-0.36) and, group 3: 1.93 μg/L (95% CI, 1.36-2.66) for bacterial and fungal infection, 0.19 μg/L (95% CI, 0.10-0.48) for rejection, and 0.31 μg/L (95% CI, 0.15-0.44) for viral infection. The area under the ROC (AUROC) for PCT, CRP and IL-6 in bacterial infection vs. rejection was 1.0 (P<0.0001), 0.842 (95% CI 0.686-0.998; P<0.0001) and 0.739 (95% CI 0.559-0.919; P 0.0046), respectively.

CONCLUSION

PCT levels were significantly higher in bacterial and fungal infection in comparison to other inflammatory markers. PCT proved to be the most specific parameter in differentiating bacterial infection from viral infection and allograft rejection.

Increased CD64 expression on polymorphonuclear neutrophils indicates infectious complications following solid organ transplantation

The aim of this study was to evaluate the diagnostic value of monitoring CD64 antigen upregulation on polymorphonuclear neutrophils (PMN) for the identification of infectious complications in the postoperative course of solid organ transplanted patients. Twenty-five kidney, 13 liver, and four pancreas-kidney transplanted patients were included. Beginning with preoperative values up to postoperative values after 3 months for each patient, the PMN CD64 Index, HLA-DR on monocytes, NKp44+ NK and NK/T cells, CXCR3+ NK cells, CXCR3+ T helper cells, CXCR3+ NK/T cells, and CD4/CD8 ratio were measured by flow cytometry. Subsequently they were correlated with confirmed postoperative complications. Measuring the PMN CD64 Index reached a sensitivity of 89% and a specificity of 65% in the detection of infectious complications. Concerning this matter, it was a significantly better marker than all other included parameters except CXCR3+ NK/T cells. In contrast, according to our results the PMN CD64 Index has no diagnostic relevance in detection of rejections. The combination of included parameters showed no improved diagnostic value. Due to its high sensitivity and specificity for infectious complications CD64 on PMN could be proven a very good indicator in evaluating suspected infectious complications in the postoperative course of transplanted patients.

Cytokine kinetics profiling in pediatric renal transplant recipients

Pediatric renal transplant recipients experience side effects of immunosuppression. Few immunoassays exist which can assess the adequacy of immunosuppression. We developed a CKT, whereby cytokine levels are measured in a five-day mixed lymphocyte reaction. We describe the in vitro cytokine responses to donor and third-party antigen in a pilot study of nine children after living-donor renal transplantation. The CKT identified five patterns of IFN-gamma secretion relative to donor and third-party alloantigen: no response to alloantigen (n = 2), hypo-response to donor (n = 3), equal response (n = 1), hyper-response to donor (n = 1), and intermediate response (n = 2). IL-2 and IL-13 patterning correlated with IFN-gamma expression. Two of nine subjects had acute rejection, which correlated with intermediate and hyper-responsive profiles. No rejection occurred during immunosuppression or donor-specific hypo-responsiveness. Significant immunosuppression was universal early after transplantation. Two of four children showed strong pretransplant responses to donor, which were regained three months post-transplant, and associated with rejection in one subject. The CKT reflects the level of immunosuppression and may offer a method to assess the adequacy of immunosuppression. A pattern of complete non-responsiveness or hypo-responsiveness correlated with lack of acute rejection. The CKT may prove useful in titrating immunosuppression and in improving live donor selection.

The potential role of C-reactive protein in distinguishing cytomegalovirus from tuberculosis and bacterial infections in renal transplant recipients

INTRODUCTION

The delay in the diagnosis of infections can be deleterious in renal transplant recipients. Thus, laboratory tests leading to an earlier diagnosis are very useful for these patients.

PURPOSE

To assess the behavior of C-reactive protein (CRP) in renal transplant recipients with a diagnosis of cytomegalovirus (CMV) infection, tuberculosis (TB) and bacterial infection (BI).

METHODS

A retrospective analysis of 129 patients admitted at our hospital, from 2006 to 2008 because of CMV, TB or BI, was carried out. Appropriate statistical analysis was done and values were expressed as medians, range.

RESULTS

When CRP levels were compared among the groups with CMV disease, TB or BI, the group with CMV disease presented lower levels of CRP (18.4 mg/L, 0.28-44 mg/L) than the TB and BI (p < 0.05) groups. The area under the receiver-operating characteristics curve, distinguishing CMV disease from TB/BI, was 0.96 (p < 0.0001), resulting in 100% sensitivity and 90.63% specificity to detect CMV disease when CRP < 44.5 mg/L. The subgroup analysis of CMV infection showed increasing levels of CRP (0.28, 16 and 29.5 mg/L) in the asymptomatic, symptomatic and invasive disease subgroups, respectively (p < 0.05).

CONCLUSION

The measurement of CRP levels may be a useful tool for differentiating CMV infection from the other types (bacterial or TB) of infection in kidney transplant recipients.

Persisting elevation of C-reactive protein after pancreatic resections can indicate developing inflammatory complications

BACKGROUND

Serum C-reactive protein (CRP) is an established discriminating factor for necrotizing pancreatitis. In this study, the CRP response with respect to inflammatory postoperative complications was examined in a large, homogeneous series of pancreatic resections in order to define a relevant clinical parameter for early detection of inflammatory postoperative complications.

METHODS

688 consecutive pancreatic resections with jejunal anastomosis were screened for inflammatory postoperative complications based on a prospective database. Ninety-one patients had at least one inflammatory postoperative complication and were compared to a subgroup of 60 consecutive patients with uneventful postoperative courses.

RESULTS

In the postoperative setting after pancreatic resection, CRP peaked on postoperative day (POD) 3 with a median serum CRP of 132 mg/L, and gradually decreased thereafter in patients with an uncomplicated postoperative course. In complicated cases (with the exception of cholangitis), increase in CRP was significantly greater, peaked on POD 3 (median CRP 173 mg/L), and persisted thereafter, whereas white blood cell count and body temperature did not differ significantly from uneventful courses until POD 6. The median day of diagnosis of inflammatory postoperative complications was POD 9. A cutoff CRP value of 140 mg/dL on POD 4 yielded a positive predictive value of 89.1% (adjusted to the prevalence of inflammatory postoperative complications: 48.7%) with a specificity of 87.1% and a sensitivity of 69.5% for inflammatory postoperative complications.

CONCLUSION

Persistence of CRP elevation above 140 mg/dL on POD 4 is predictive of inflammatory postoperative complications and should prompt an intense clinical search for major septic processes (e.g. pancreatic fistula or abscess) if pneumonia and wound infection are unlikely or excluded.

C-reactive protein as early predictor for infectious postoperative complications in rectal surgery

BACKGROUND

This study evaluated the role of the acute phase C-reactive protein (CRP) in the postoperative course of a large series of rectal resections on the basis of a prospective database. Main focus of this study was the early identification of complications.

MATERIALS AND METHODS

Three hundred eighty-three rectal resections with primary anastomosis for rectal cancer were screened for infectious postoperative complications. Forty-eight complicated cases were identified and matched with 48 patients with an uneventful postoperative course.

RESULTS

In the postoperative setting, CRP peaked on postoperative day (POD) 2 with a median serum CRP of 140 mg/l and gradually declined thereafter in uncomplicated cases. In complicated cases, CRP elevation generally persisted after POD 2, whereas white blood cells and body temperature were within normal range in the early postoperative period. A cutoff CRP value of 140 mg/dl on PODs 3 and 4 resulted in predictive values of 85.7 and 90.5% (adjusted to the prevalence: 37.6 and 50.3%), sensitivities of 80.0 and 54.3%, and specificities of 81.0 and 92.3% for a complicated postoperative course (P<0.001), respectively.

CONCLUSION

Persistent CRP elevation and elevation of serum CRP above 140 mg/dl on PODs 3-4 are predictive of infectious postoperative complications and should prompt intense clinical search for an inflammatory process, especially for an anastomotic leak if pneumonia and wound infection are unlikely or excluded.

Differentially Expressed Genes in Postperfusion Biopsies Predict Early Graft Dysfunction After Liver Transplantation

BACKGROUND

Preservation induced injury is a major contributing factor to early graft dysfunction in liver allograft recipients. We hypothesized that changes in gene expression represent the earliest indicator of ischemia/reperfusion-related injuries measurable in the graft and could be used as prognostic marker for the occurrence of graft-related complications.

METHODS

We studied the expression of 67 genes, known to play a role in acute inflammatory processes by real-time polymerase chain reaction in 59 postperfusion biopsies. The level of expression was correlated with the occurrence of graft-related complications.

RESULTS

We identified six genes that were significantly correlated with the occurrence of early graft dysfunction (Spearman test, two-tailed; P<0.05). High C-reactive protein (CRP) gene expression levels correlated significantly with the need of therapeutic interventions due to graft-related complications (P=0,011). Furthermore, five genes related to vascular endothelial cell physiology (CTGF, WWP2, CD274, VEGF. and its receptor FLT1) showed significantly reduced expression in the postperfusion biopsies of patients with need of therapeutic interventions due to graft-related complications in the first month (P<0.05). Using a risk score based on the expression of these five genes, complications could be predicted with 96% sensitivity (ROC analysis, specificity: 74%, positive predictive value: 72%, negative predictive value: 96%).

CONCLUSION

Quantitative gene expression analysis in postperfusion biopsies may be a valuable tool to prospectively identify patients at risk for early clinical allograft dysfunction after liver transplantation.

Bloodstream infection following 217 consecutive systemic-enteric drained pancreas transplants

Background

Combined kidney pancreas transplantation (PTx) evolved as excellent treatment for diabetic nephropathy. Infections remain common and serious complications.

Methods

217 consecutive enteric drained PTxs performed from 1997 to 2004 were retrospectively analyzed with regard to bloodstream infection. Immunosuppression consisted of antithymocyteglobuline induction, tacrolimus, mycophenolic acid and steroids for the majority of cases. Standard perioperative antimicrobial prophylaxis consisted of pipercillin/tazobactam in combination with ciprofloxacin and fluconazole.

Results

One year patient, pancreas and kidney graft survival were 96.4%, 88.5% and 94.8%, surgical complication rate was 35%, rejection rate 30% and rate of infection 59%. In total 46 sepsis episodes were diagnosed in 35 patients (16%) with a median onset on day 12 (range 1–45) post transplant. Sepsis source was intraabdominal infection (IAI) (n = 21), a contaminated central venous line (n = 10), wound infection (n = 5), urinary tract infection (n = 2) and graft transmitted (n = 2). Nine patients (4%) experienced multiple episodes of sepsis. Overall 65 pathogens (IAI sepsis 39, line sepsis 15, others 11) were isolated from blood. Gram positive cocci accounted for 50 isolates (77%): Coagulase negative staphylococci (n = 28, i.e. 43%) (nine multi-resistant), Staphylococcus aureus (n = 11, i.e. 17%) (four multi-resistant), enterococci (n = 9, i.e. 14%) (one E. faecium). Gram negative rods were cultured in twelve cases (18%). Patients with blood borne infection had a two year pancreas graft survival of 76.5% versus 89.4% for those without sepsis (p = 0.036), patient survival was not affected.

Conclusion

Sepsis remains a serious complication after PTx with significantly reduced pancreas graft, but not patient survival. The most common source is IAI.

Assessment of pretransplant inflammation in pediatric renal allograft recipients

Pretransplant (Tx) inflammation is linked to adverse outcomes in adult Tx recipients but no such data exist for children. Our study evaluated the predictive value of three pre-Tx inflammatory markers: serum C-reactive protein (CRP), Neopterin (Neo) and interleukin (IL) 12, in determining outcome. Pre-Tx serum on 51 children (mean age 11 years) transplanted between 1985 and 2000 was analyzed. Data on other variables were abstracted from patient records. Primary end-points were graft survival and acute rejection (AR). Kaplan-Meier and log-rank statistics compared endpoints in patients at different quartiles for each marker. Cox regression analysis was used to determine the independent effect of the markers on the end-points. The mean CRP, Neo, and IL-12 were 1.3 mg/l, 1.78 ng/ml, and 123 pg/ml, respectively. The mean CRP, Neo, and IL-12 were not different between the patients with and without AR or graft loss (P > 0.4 for all). Neither rejection-free survival nor graft survival was affected by CRP, Neo, or IL-12 quartiles. Cox-regression analysis demonstrated no predictive value of any marker on outcome. Unlike adults, a single pre-Tx determination of inflammatory markers was not predictive of AR or graft loss in children, indicating that the pathogenesis of AR may be different in children.

Analysis of the cardiovascular risk profile in stable kidney transplant recipients after 50% cyclosporine reduction

BACKGROUND

Long-term use of cyclosporine (CsA) contributes to post-transplant cardiovascular disease (CVD). Hence, a reduction in CsA dosage in kidney transplant recipients (KTR) may improve long-term outcomes. We analyzed the effects of 50% CsA dose reduction on the CVD risk profile in stable KTR.

METHOD

Thirty-one KTR on a regimen of CsA, prednisone and mycophenolate mofetil (MMF) were studied. Patients were randomized to either a) continue their previously determined CsA dose (control group, n = 15) or b) lower their CsA dose by 50% (CsA reduction group, n = 16). Renal function, blood pressure, lipid profile, plasma homocysteine (HCY), C-reactive protein (CRP), fibrinogen, and uric acid were compared at baseline and at 6 months.

RESULTS

At 6 months, there was a significant improvement in allograft function, systolic blood pressure, number of anti-hypertensive medications and serum uric acid levels in the CsA reduction group. No significant decrease in plasma HCY, CRP, fibrinogen or improvement in lipid profile was found. In contrast, in the Control group, there was a significant increase in HCY, uric acid, and triglycerides. No acute rejection occurred in either group.

CONCLUSIONS

A greater reduction in CsA dose could further improve CVD risk profiles, although this may increase the risk of acute or subclinical rejection.

Analytical performance of a highly sensitive C-reactive protein-based immunoassay and the effects of laboratory variables on levels of protein in blood

C-reactive protein (CRP) is an acute-phase reactant whose levels increase in response to a variety of inflammatory stimuli. Elevated levels in serum are observed after trauma, tissue necrosis, infection, surgery, and myocardial infarction and are associated with an increased risk of cardiovascular disease. CRP levels are also elevated in noninflammatory states, such as obesity, sleep disturbances, depression, chronic fatigue, aging, and physical inactivity. In this study, the performance of a highly sensitive CRP enzyme immunoassay was evaluated, along with common laboratory variables (specimen type, processing time, and storage conditions) that may influence measured blood concentrations of CRP. The measurement range of the assay was from 0.4 to 50 microg/liter. Total imprecision (coefficient of variation) ranged from 8.1 to 11.4%. CRP levels obtained with the enzyme immunoassay were highly correlated with those obtained with an automated immunonephelometric assay. Comparable results were obtained for plasma (heparin and EDTA treated) and serum samples, and levels were unaffected by delays in sample processing and storage temperature. CRP levels were also unaffected by up to seven freeze-thaw cycles. The median CRP concentration in healthy adults was determined to be 0.94 mg/liter, with a 95% working reference interval of 0 to 6.9 mg/liter. In view of these data, we recommend that serial serum or plasma samples for CRP should be stored at 4 degrees C for short periods of time or at -70 degrees C for longer periods and tested within the same run to minimize interassay variability.