Chlamydia pneumoniae infection in patients after kidney transplantation treated with spiramycin

INTRODUCTION

Previous research has pointed to a role of Chlamydia pneumoniae infection in the development of chronic renal allograft dysfunction, chronic liver rejection, and vasculopathy in the transplanted heart. The aim of this study was to evaluate the presence of C. pneumoniae prior to and after kidney transplantation as well as to determine the role of spiramycin therapy among kidney transplant recipients.

MATERIALS AND METHODS

The study group consisted of 50 patients (25 pairs) who received kidney transplants from cadaveric donors. One of the 2 kidneys from a donor was transplanted to a patient randomized to spiramycin (2 x 3 million U/d orally for 3 months; group S) and the other to a patient assigned as control (group C). Markers of infection were assessed on day 1 posttransplantation and 3 months later (average, 94 days). All 50 patients were examined for the presence of bacterial DNA in peripheral blood leukocytes using real-time polymerase chain reaction (PCR) and for titers of serum anti C. pneumoniae immunoglobulin (IgG) and IgA antibodies using microimmunofluorescence (MIF). C. pneumoniae infection was diagnosed by the presence of C. pneumoniae DNA in peripheral blood leukocytes or positive antibodies of both classes.

RESULTS

C. pneumoniae infection was initially diagnosed in 14 patients among group S and 8 patients among group C (P = not significant [ns]) and after 3 months in 12 and 9 patients, respectively (P = ns). Conversion from positive to negative C. pneumoniae status occured in 7 patients among group S and 1 patient among group C (P = .04). Conversion from negative to positive C. pneumoniae status occured in 5 patients from group S and 2 patients from group C (P = ns).

CONCLUSIONS

These results suggest a possible role for spiramycin treatment of C pneumoniae infection in kidney allograft recipients. C. pneumoniae infection diagnosis and treatment should be considered to be routine for every patient awaiting transplantation.

Machine perfusion preservation improves renal allograft survival

Machine perfusion (MP) has been used as the kidney preservation method in our center for over 10 years. The first, small (n = 74) prospective, single-blinded randomized study comparing MP and Cold Storage (CS) showed that the incidence of delayed graft function was higher after CS. There have been no reports in the literature on the effect of storage modality on long-term function of renal allografts. This paper presents an analysis of long-term results of renal transplantation in 415 patients operated on between 1994 and 1999. Of those, 227 kidneys were MP-stored prior to KTx. The control group consisted of 188 CS kidney transplants. Kidneys were not randomized to MP or to CS. Donor demographics, medical and biochemical data, cold ischemia time, HLA match and recipient data were collected. Standard triple-drug immunosuppression was administered to both groups. Mortality, graft survival and incidence of return to hemodialysis treatment were analyzed. Despite longer cold ischemia time and poorer donor hemodynamics in MP group, 5-year Kaplan-Meier graft survival was better in MP-stored than in CS-stored kidneys (68.2% vs. 54.2%, p = 0.02).

CONCLUSION

In this nonrandomized analysis, kidney storage by MP improved graft survival and reduced the number of patients who returned to dialysis.

Intraoperative Blood Flow Measurements in Organ Allografts Can Predict Postoperative Function

A reliable method to recognize the extent of ischemia/reperfusion injury in transplantation is needed in order to tailor the immunosuppressive scheme to the needs of a damaged organ. This study sought to assess the correlation between the total and the parenchymal blood flow into a transplanted kidney (n = 71) or liver (n = 15) shortly after revascularization with the early function of the organ after transplantation. The total blood flow in the renal artery in kidney recipients or in the hepatic artery and portal vein in liver recipients was measured by an electromagnetic flowmeter. The parenchymal blood flow (in several parts of the transplanted organ) was assessed using a laser-Doppler flowmeter. Two measurements were always taken after revascularization (5 to 60 minutes apart). Vascular resistance (VR) as calculated by the difference between the mean arterial pressure (MAP) and the central venous pressure (CVP) was correlated with immediate kidney or liver function parameters. Neither total renal blood flow (RBF) nor VR was different between the immediate function (IF) and delayed graft function (DGF) groups of kidney transplant patients. However, the cortical (parenchymal) blood flow was significantly greater in the IF than the DGF group at 5 minutes: 29.98 +/- 6.13 mL/min/100 g vs 23.56 +/- 6.46 mL/min/100 g (P < .001). The difference was even more significant at 35 minutes: 33.94 +/- 7.47 mL/min/100 g vs 15.47 +/- 3.34 mL/min/100 g (P < .0001). Among liver transplant patients, the results suggested a correlation between hepatic arterial blood flow and early graft viability and function. The most reliable predictor of early graft function was the portal blood flow, which correlated with the volume of secreted bile as well as the bilirubin, and transaminase levels and coagulation profile. Further studies must confirm the value of measurements of total and parenchymal blood flow in organ transplant recipients.

Surgical complications of simultaneous pancreas-kidney transplantation: a 16-year-experience at one center

Fifty-one simultaneous pancreas-kidney transplants (SPKT) were performed between 1988 and 2004 in patients of mean age 34 years and 23 years duration of diabetes treatment. All kidney and pancreas recipients were on maintenance hemodialysis therapy prior to SPKT. The pancreas with duodenal segment and the kidneys were harvested from cadaveric heart-beating donors. Cold ischemia time in UW solution varied from 4 to 14 hours (mean, 9 hours 35 minutes). Twenty patients had the duodenal segment sutured to the urinary bladder, and the remaining 31 grafts were drained to an isolated ileal loop. Quadruple immunosuppression was administered as well as an anticoagulant and antibiotic prophylaxis. Forty-nine patients (49/51, 96%) regained insulin independence in the immediate postoperative period; 44 (86%) displayed immediate graft function. The remaining patients experienced postoperative ATN, the longest duration was 18 days. Of 51 patients, 38 (14.5%) are alive (follow-up, 6 to 180 months), 26 (68.5%) have good pancreatic function, and 34 (89%), good kidney function. Nineteen (50%) patients regard their quality of life as improved compared to their pretransplant status, which is mainly attributed to being dialysis and insulin free. Of 19 patients, 14 (74%) reported measuring glycemia regularly due to fear of losing the pancreas graft. Of 19 persons, seven (37%) returned to work after transplantation. Four (8.3%) lost their kidney graft secondary to vascular complications (n = 2) or rejection (n = 2). Four pancreas grafts with bladder drainage required conversion to enteric drainage owing to persistent urinary infections or urinary fistulae. Fifteen (29%) patients lost their pancreatic grafts within 1 year of transplantation due to the following: vascular complications (n = 12), septic complications (n = 1), or rejection (n = 2). Thirteen patients died within 1 year after transplantation, 5 of septic complications, 5 of neuroinfection, 1 of pulmonary embolism, and 2 of myocardial infarction. In conclusion, SPKT is a successful treatment for diabetic nephropathy, burdened by the possibility of serious complications.

Increased mRNA Expression of Transforming Growth Factor Beta in the Arterial Wall of Chronically Rejected Renal Allografts in Humans

INTRODUCTION

Transforming growth factor beta (TGF-beta) has an established role in interstitial damage of renal transplants during chronic rejection (CR). However, its involvement in transplant vasculopathy is not clear. The aim of the study was to assess TGF-beta gene expression in the walls of large-caliber arteries within chronically rejecting renal allografts. We evaluated associations between gene expression of this factor and intimal thickness or clinical data.

MATERIAL AND METHODS

Renal artery samples of kidney allografts were obtained from 20 hemodialysis patients with end-stage renal graft disease due to CR, who were undergoing graftectomy. The control group included 32 hemodialysis patients with end-stage renal disease, undergoing nephrectomy due to autosomal dominant polycystic kidney disease (n = 12), chronic pyelonephritis (n = 13), or kidney limited tumor (n = 7). Gene expression of TGF-beta was measured using real-time PCR.

RESULTS

TGF-beta mRNA expression was 3.25-fold higher in CR than in control patients (P < .001). Expression of mRNA for this cytokine was not influenced by the following factors: intimal thickness; age; serum cholesterol, triglycerides and glucose; BMI; graft survival; time of dialysis before transplantation; total ischemic time; immunosuppressive regimen; incidence of acute rejection episode; panel reactive antibodies; and period of dialysis before graftectomy. TGF-beta is involved in neointimal formation in CR.

Chlamydia Pneumoniae Infection and Ischemic Heart Disease in Hemodialysis Patients

INTRODUCTION

Ischemic heart disease and other atherosclerotic complications are the prominent causes of death among hemodialyzed end-stage renal disease (ESRD) patients and renal transplant recipients. Numerous articles in recent years have raised the possibility of an infective factor, especially Chlamydia pneumoniae, in the development of atherosclerosis and its complications. The aim of this study was to assess the incidence of chronic C pneumoniae infection and its association with ischemic heart disease and atherosclerosis in a population of patients with ESRD awaiting renal transplantation.

MATERIAL AND METHODS

The studied group consisted of 164 subjects: 99 ESRD patients (heart disease [HD] group) who were hospitalized for vascular access creation (27), pretransplantation nephrectomy (47), or kidney transplantation (25), and a control group of 65 subjects consisting of 50 healthy blood donors and 15 multiorgan donors. C pneumoniae was detected in vascular wall fragments, kidney biopsy specimens and peripheral blood monocytes using real time polymerase chain reaction (PCR). Serum immunoglobulin IgG and IgA anti-C pneumoniae antibodies were detected using Enzyme-linked immunosorbent assay (ELISA) and a lipid profile (cholesterol, high-density lipoprotein [HDL], low-density lipoprotein [LDL], and triglycerides [TG]) was obtained. Data on cardiovascular disease events, smoking history, diabetes, hypertension, cause, and length of renal failure were collected and analyzed. The existence of atherosclerotic lesions was detected using ultrasound (US) Doppler examination of aortic bifurcation. Chronic C pneumoniae infection was diagnosed on the basis of detection of both IgA and IgG antibodies and/or the detection of C pneumoniae DNA in vascular wall fragments or peripheral blood monocytes. After a follow-up of 32 months, data on cardiovascular events and patient history were collected again.

RESULTS

Chronic C pneumoniae infection affected 46.5% (46/99) of HD patients and 9% (6/65) of controls (P < .05). Among HD patients, 26.3% (26/99) had ischemic heart disease (IHD) versus 6% in the control group. Among C pneumoniae-infected HD patients, IHD was more frequent (39.1%) than in noninfected HD patients (15%; P < .05). Within the 32-month observation period of the HD group, cardiac pain was observed in 11 (24%; 11/46) infected patients versus 3 (5.7%; 3/53) patients without C pneumoniae infection (P < .05). Exacerbation of previously diagnosed IHD was observed in 8 (44%; 8/18) cases in the C pneumoniae-infected group versus 0 (0%; 0/8) in the uninfected patients (P < .05).

CONCLUSIONS

Chronic C pneumoniae infection affects hemodialysis patients more frequently than healthy subjects. Hemodialysis patients with C pneumoniae infection are at the greater risk of exacerbation of existing IHD.

C4d Complement Split Product in Diagnosis of Immunological Activity of Chronic Allograft Nephropathy

INTRODUCTION

Activation of the humoral branch of the immunological response is currently believed to play an important role in pathogenesis of chronic allograft nephropathy. The impact of humoral alloreactivity, indicated by the presence of C4d deposits in peritubular capillaries of a renal allograft, on the development of chronic allograft nephropathy is a significant problem in transplantation. The aim of the study was to assess and correlate C4d expression in patients with chronic allograft nephropathy, with clinical and morphological variables, as well as to assess the impact of a change in immunosuppression regimen on posttransplant course and renal allograft morphology.

PATIENTS AND METHODS

Twenty-six patients with chronic allograft nephropathy underwent biopsies to correlate C4d expression with clinical parameters and morphological findings. In all patients azathioprine was replaced with mycophenolate mofetil with additional CsA dose reduction in 12 patients. After 1 year, 14 protocol biopsies were performed.

RESULTS

The frequency of C4d peritubular capillary deposition among patients with chronic allograft nephropathy was 30%. C4d expression appeared later after transplantation, was correlated with chronic allograft glomerulopathy and proteinuria but not other clinical or histological variables. C4d deposits displayed no independent impact on serum creatinine level. Proteinuria was significantly more reduced in the C4d(+) group. Progression of chronic morphological changes was significantly accelerated in the C4d(+) group.

CONCLUSION

C4d peritubular capillary expression did not differentiate patients after immunosuppression enhancement, but it predisposed to progression of chronic morphological findings during 1-year observation.

Chlamydia Pneumoniae Infection: An Additional Factor for Chronic Allograft Rejection

INTRODUCTION

Chronic rejection (CHR) of organ allografts, one of the most significant problems in modern transplantation, is not fully understood. This study sought to evaluate the influence of selected parameters on late kidney transplant function.

PATIENTS AND METHOD

The studied group consisted of eighty-six patients who received allogeneic transplants between 1988 and 1999 for leukocyte Chlamydia pneumoniae-DNA, immunoglobulin (Ig)A/IgG anti-C pneumoniae, blood lipids, ischemic damage in the donor and during organ preservation, HLA mismatch, and acute rejection episodes.

RESULTS

Eighty-six patients were segregated as 26 patients (30%) with histologically proven chronic graft rejection (CHR[+]) and 59 patients (70%) without (CHR[-]). The presence of C pneumoniae-DNA in peripheral blood leukocytes was significantly more frequent in CHR(+) than CHR(-) group (46% vs 20%). Patients with leukocytes positive for C pneumoniae-DNA more frequently (50%) had CHR than patients negative for C pneumoniae-DNA (22%). CHR(+) patients showed significantly lower HDL levels (47 mg/dL vs 58 mg/dL) and higher triglyceride levels (193 mg/dL vs 148 mg/dL). To study the cumulative effect of differences between the CHR(+) and CHR(-) groups, we applied a multiple binary logistic regression analysis. An econometric model enabled us to calculate the probability of CHR for a given patient taking into account covariates chosen by means of stepwise selection: the presence of C pneumoniae-DNA in blood leukocytes, the use of continuous pulsatile perfusion in hypothermia, myocardial infarction occurrence, and triglyceride concentrations.

CONCLUSION

The presence of C pneumoniae-DNA in peripheral blood leukocytes increased the risk of CHR, which may be predicted by a multifactor analysis of chosen parameters.

Presence of Chlamydia pneumoniae in patients with and without atherosclerosis

Data published over the past decade show that Chlamydia pneumoniae is likely associated with the development of atherosclerosis. The aim of this study was to ascertain whether C. pneumoniae infections occur more frequently in patients with atherosclerosis than in healthy subjects. A total of 517 persons were studied. Serum samples, leukocytes, and tissue samples were assayed for the presence of C. pneumoniae-specific IgG and IgA antibodies and C. pneumoniae DNA. C. pneumoniae DNA was found in renal, iliac, and brachial vessels, but it was not detected in radial arteries. C. pneumoniae DNA was found most often in directional coronary atherectomy tissue specimens (11/41, 26.8%), but it was also found in the leukocytes of 14.9% (28/188) of patients with atherosclerosis and 24.6% (28/114) of patients without atheroma changes in vessels. Specific IgG and IgA antibodies were present in 63.8 and 49.9% of atheroma patients, respectively. The prevalence of C. pneumoniae antibodies differs significantly in patients with and without atherosclerosis (for IgG, p=0.002, and for IgA, p=0.006). The identification of persons with chlamydial infection of atherosclerotic arteries necessitates the examination of vascular tissues obtained during revascularization procedures. Serological investigation alone cannot identify individuals with vascular chlamydial infections. Detection of C. pneumoniae DNA in peripheral blood mononuclear cells does not seem to be the exclusive marker of persistent vascular infection. A more easily accessible parameter that allows prediction of chlamydial vascular infection is required.

Infectious Complications After Simultaneous Pancreas–Kidney Transplantation

Simultaneous pancreas-kidney transplantation (SPKT) improves long-term survival of insulin-dependent diabetes mellitus patients with diabetic nephropathy. The increasing success of SPKT is a result of improved surgical technique, better organ preservation, potent antirejection therapy, and effective use of antibiotics to prevent and treat infectious complications. However, morbidity and mortality following SPKT remain high mainly owing to infection. From 1988 to 2004, the 51 patients who underwent SPKT were 32 women and 19 men of mean age 34 +/- 4 years old with diabetes and end-stage renal disease. The mean duration of diabetes mellitus was 23 +/- 4 years. The incidence of HCV and HBV infections were 19.6% and 13.7%, respectively. Preoperative work-up included identification and elimination prior to surgery of potential sources of infection. All patients prior to SPKTx had been treated by dialysis (26 +/- 20 months). The kidneys were always placed into the left retroperitoneal space first; at the same time the pancreatic grafts were prepared on the back table. The reconstruction of the superior mesenteric and the splenic arteries was performed using a Y graft of donor iliac artery to the common or external donor's iliac artery. The pancreas was transplanted intraperitoneally to the right iliac vessels. The portal vein was sutured to the common or external iliac vein and the arterial conduit of donor iliac artery. In 20 of the patients, bladder drainage and in 31, enteric drainage was used for the pancreatic juice exterioration. Patients received immunosuppression with a calcineurin inhibitor (tacrolimus or cyclosporin), mycophenolic acid or azathioprine, and steroids. Antibody induction (alternatively anti-IL-2 monoclonal antibody or ATG) was used in last 38 patients. Antibacterial (tazobactam) and antifungal (fluconazole) as well as antiviral (gancyclovir) prophylactic treatment was given to all patients for 7 to 10 days after transplantation. Thirty-eight recipients are alive, 26 with function of both grafts; 8 with functioning kidney grafts; and 4 with nonfunctioning grafts on dialysis treatment from 1 to 14 years after transplantation. Thirteen patients (24.5%) died during the first year after transplantation. Infectious complications were the main cause of death. Systemic infections accounted for the death of five patients and CNS infection for death of another five patients. Three patients died with functioning grafts due to cardiopulmonary disorders (myocardial infarction, pulmonary embolus) early in the postoperative period. A total of 102 infections were diagnosed in 51 patients during the posttransplant course. Twenty-one episodes of CMV infection (systemic 20, duodenal site 1), 73 bacterial infections (systemic 13, pulmonary 13, urinary tract 15, intestinal 8, wound 23), and 8 fungal infections (central nervous system 5, gastrointestinal tract 3). Some patients had more than one type of infection. Overall mortality in the investigated group was 24.5%. Infectious complications were the main cause of death (77%), including systemic infection (38.5%) and CNS infection (38.5%). The predominant etiology of the systemic infections was bacterial. The etiology of CNS infections was fungal. In conclusion, infectious complications are the main cause of morbidity and mortality following SPKT. The early diagnosis of infection, particularly fungal complications, is necessary. The administration of broad-spectrum prophylactic antibiotics, antifungal, and antiviral agents is recommended.

Quality of Life After Simultaneous Pancreas–Kidney Transplantation

Even recipients with satisfactory function of transplanted pancreas and kidney may show physical and/or social disability due to diabetic complications. Our aims were to evaluate diabetic complications influencing recipient quality of life and to assess patients' psychosociological status. Nineteen patients with functioning grafts who consented to take part in the study, underwent clinical evaluation and answered questions regarding their quality of life. Results showed excellent endocrine pancreatic function in 17 patients. In most recipients, insulin activity and C-peptide levels were elevated owing to systemic venous drainage. Opthalmological examination revealed blindness in 7 patients (in 4 cases with onset following SPKTx) and retinopathy in 13 patients (in 5 cases it appeared after SPKTx). Assessment of the cardiovascular system revealed satisfactory cardiac function in 16 of 19 patients; 4 patients underwent amputation of a lower limb following SPKTx. All 19 recipients admitted to a great benefit of transplantation; most patients declared ability to organize their life activity and social functions and 4 had regular employment. Conversely, most patients were afraid of graft loss, and half were often sad and even depressed.

Extracellular matrix proteins, proteolytic enzymes, and TGF-beta1 in the renal arterial wall of chronically rejected renal allografts

Chronic rejection (CR) is the leading cause of long-term failure of transplanted kidneys. The vascular hallmark is intimal hyperplasia, accompanied by macrophage, foam cell, and T-cell infiltration. Intimal thickening results from the migration and proliferation of smooth muscle cells and increased deposits of extracellular matrix (ECM) proteins, due to release of growth factors and cytokines as well as altered ECM protein turnover. We assessed the content of fibronectin (FN) and transforming growth factor-beta1 (TGF-beta1) as well as the activities of collagenase and cathepsin B and L in renal artery walls of chronically rejected human renal allografts. We investigated renal artery samples from 8 patients with CR undergoing graftectomy, 12 patients undergoing nephrectomy, and 7 organ donors. The results were related to the DNA content of homogenates. Cathepsin B and L activities were significantly higher among those with compared with donors (P =.022). There was a trend toward higher collagenase activity in CR compared with donors and the nephrectomy group. TGF-beta1 was significantly enhanced in CR compared with donors (P =.010), and showed a trend toward higher concentrations in CR compared with the nephrectomy group. The trend was toward lower FN concentrations in CR compared with the nephrectomy group and toward higher concentrations compared with donors. Summarizing, renal CR is accompanied by enhanced proteinase activity, alterations of ECM proteins, and increased TGF-beta1 in the renal artery wall. We conclude that ECM turnover and cytokines play an important role in neointimal formation and CR pathogenesis.

Pneumonia in kidney allograft recipients

Infectious complications, including pneumonia, remain one of the leading causes of morbidity and mortality in kidney allograft recipients. The aim of the study was to evaluate the relationship between pneumonia occurrence and treatment duration and recipient age, cause of native kidney insufficiency, dialysis duration, time between transplantation and onset, HLA matching, PRA immunosuppressive protocol, acute rejection incidence and treatment, kidney function at the pneumonia onset, as well as presence of comorbid conditions. One hundred and twenty pneumonia cases occurred in kidney allograft recipients transplanted between 1991 and 2000 with 12 to 120 months follow-up. Twenty five percentage of pneumonia episodes were diagnosed during the first posttransplant month, 25% between 2 and 6 months, and 25% at 0.5 to 3 years. Treatment duration measured from pneumonia onset to the study endpoint of recovery, which was defined as antibiotic withdrawal, show 50% of patient we cured after 15 days and 75% after 24 days of treatment. The risk of prolonged pneumonia treatment was associated with: second versus first kidney transplantation with RR = 2.3 (P <.02) and medians of treated time 28 versus 15 days; as well as serum creatinine level above 2 mg/dL (RR = 1.4; P <.098). Exposure to enhanced-potency immunosuppressive protocols including induction therapy with mono- or polyclonal antibodies increased the RR = 1.65 (P <.02), and lengthened the time to 18 versus 14 days. Maintenance immunosuppression with agents other than cyclosporine also enhanced the risk. (RR = 2.18; P <.068).

Simultaneous pancreas-kidney transplantation: analysis of donor factors

There are no urgent indications for simultaneous pancreas-kidney transplantation. So our policy is to harvest only a pancreas in good biologic condition. The criteria for acceptance of a pancreas donor are: age 15 to 40 years, ICU stay < 7 days, no clinical signs of infection, negative virologic status, no history of hypotension or cardiac arrest, serum amylase elevation below three times normal values, controllable hyperglycemia, no history of pancreatic disease, no history of abdominal trauma damaging the organ, no history of alcohol addiction, BMI < 25, no functional or anatomical lesions of the kidneys, and expected ischemia time less than 12 hours. The proper selection of a pancreas donor allows one to achieve good insulin secretion immediately after transplantation. In 2000 to 2002 all 20 pancreases transplanted at transplant center displayed immediate secretory function after transplantation.