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S Emre

Publications and source records attributed to S Emre.

At least 91 records · Page 5Linked to original sources
PubMed1997

Assessment of liver allograft function by hyaluronic acid and endothelin levels.

BACKGROUND: Sinusoidal endothelial cells are considered the primary site of preservation-reperfusion injury occurring during cold storage and reperfusion. Hyaluronic acid (HA) and endothelin-1 (ET) are markers of endothelial cell integrity. The aim of this study was to evaluate the possible correlation between these markers and early graft function following liver transplantation. MATERIALS AND METHODS: Blood samples were collected from 85 adult orthotopic liver transplant recipients at the following time points: before surgery, just before reperfusion, first and last 20 cc of caval effluent, 30, 60, and 120 min after reperfusion, and on postoperative day (POD) 1. Levels of both HA and ET were measured by sandwich enzyme-binding assay. HA uptake was also defined for every sample as the ratio of the actual measurement to the value obtained just before reperfusion. RESULTS: Patients with severe liver disease displayed significantly higher pretransplant HA and ET levels compared with those of less advanced illness. Poor early graft function (PEGF) was defined as peak enzyme levels on the first three PODs higher than 2500 U/L and prothrombin time longer than 16 s on POD 2. Patients with PEGF (n = 9) showed significantly lower HA uptake than patients with good graft function (n = 76) at 60 and 120 min after reperfusion. There was also a significant difference in the average uptake values measured in the last 20 cc of caval effluent between the two groups. We could not find any difference in ET levels between these two groups. CONCLUSIONS: Perioperative HA uptake measurement may be an additional marker to evaluate early graft function.

Adult↗
PubMed1997

Infectious ocular complications in orthotopic liver transplant patients.

We report the frequency and type of infectious ocular complications following orthotopic liver transplantation (OLT) and review diagnostic and therapeutic strategies. During the period September 1988 through November 1994, 684 patients underwent OLT at Mount Sinai Hospital (New York). Nine orthotopic liver transplant patients (1.3%) developed ocular infections: Candida albicans endophthalmitis (2), Aspergillus fumigatus endophthalmitis (1), cytomegalovirus retinitis (4), herpes simplex virus keratitis (1), and varicella-zoster virus panophthalmitis (1). The mean time from OLT to ocular symptoms was 42 days for patients with fungal infections and 128 days for patients with viral infections. Blurred vision was the commonest symptom (five of nine cases). The mean duration of follow-up was 2 years (range, 33 days to 5 years). Permanent loss of vision occurred in three patients, five had improvement in visual acuity, and one died of disseminated aspergillosis 33 days after OLT. Infectious ocular complications following OLT may occur as isolated events or with disseminated disease. Fungal infections occur earlier (mean, 42 days after OLT) than viral infections (mean, 4 months after OLT). The clinical presentation may be atypical; aggressive vitreoretinal procedures and serial examinations may be required to establish the diagnosis. Cytomegalovirus retinitis in orthotopic liver transplant patients may not require life-long maintenance therapy with antiviral agents.

Adult↗
PubMed1997

Effluent levels of thrombomodulin predict early graft function in clinical liver transplantation.

Thrombomodulin is a surface protein on vascular endothelial cells that serves as a binding site for thrombin and plays an important role as an anticoagulant factor. We correlated plasma thrombomodulin levels with early graft function after liver transplant in 58 recipients. Blood samples were collected at the following time points: before surgery, just before reperfusion, 30, 60, 120 min after reperfusion, and post-operative day 1. The first and last 20 cc of caval effluent were also collected. Plasma thrombomodulin levels were measured by a sandwich enzyme-binding assay in the blood samples; tissue expression was determined by immunohistochemistry. Poor early graft function was defined as peak aspartate aminotransferase (AST) or alanine aminotransferase (ALT) >2500 U/l during the first 3 post-operative days and prothrombin time >16 s on post-operative day 2. Thrombomodulin levels in the first 20 cc of caval effluent ranged from 1.33 to 91 FU/ml and showed a significant positive correlation with ischemic time, intra-operative blood transfusion requirement, and early graft function. In grafts with high effluent thrombomodulin (>20 FU/ml, n=12), the incidence of poor early graft function and primary nonfunction was 66.7% and 25.0%, respectively; in grafts with low effluent thrombomodulin (<20 FU/ml, n=46), graft function was not impaired. By immunohistochemistry, thrombomodulin was detected in large vessels of every donor liver. Sinusoidal cells, however, showed positive staining only in livers with poor early graft function. Effluent thrombomodulin levels reflect the extent of preservation injury and might be a useful marker for predicting graft function after liver transplantation.

Adult↗
PubMed1997

Differential contribution of graft and recipient to perioperative TNF-alpha, IL-1 beta, IL-6 and IL-8 levels and correlation with early graft function in clinical liver transplantation.

Cytokines, produced by both the recipient and the newly vascularized allograft, are central mediators in the inflammatory response to allografted tissue. This study examines the relationship between pre- and intraoperative levels of TNF, IL-1, IL-6, and IL-8 and hepatic allograft function in the early postoperative period and also determines which cytokines are produced in a significant amount by the newly vascularized allograft. Baseline levels of IL-6 and IL-8 tended to be higher in patients with more advanced disease and showed an increase during the anhepatic period. TNF and IL-1 remained stable from baseline to anhepatic phase. IL-1 showed an increase from portal vein to effluent samples, suggesting that the graft has an important contribution to circulating IL-1 levels. Analysis of the data according to early graft performance revealed extremely high levels of effluent IL-1, IL-6 and IL-8, and the prolonged elevation of the latter two cytokines in patients with poor early graft function. Our findings demonstrate that sequential perioperative measurements of proinflammatory cytokines can be useful in monitoring graft function.

Adult↗
PubMed1996

Safe use of hepatic allografts from donors older than 70 years.

Between March 1991 and August 1995, 36 livers from donors >/=70 years old were transplanted. In donors, we recorded the following risk factors: alanine aminotransferase > 120 and rising, dopamine dose > 15 microg/kg/min, hypotension (systolic blood pressure <80) >1 hr, stay in the intensive care unit >5 days and body mass index >/=27. In 35 recipients, we recorded pretransplant United Network for Organ Sharing (UNOS) status, cold/warm ischemia time, intraoperative blood loss, and occurrence of poor early graft function or primary nonfunction. Mean recipient age was 55 years (range, 25-75 years). Four recipients were UNOS status 1, 19 were UNOS 2, and 12 were UNOS 3. Two livers were used as second grafts for primary graft nonfunction. Mean donor age was 73 years (range, 70-84 years). Intracranial bleeding was the cause of death in the majority of donors. The 36 donors had 40 risk factors; 10 donors had >1 risk factor. Mean cold and warm ischemia times were 9:08 +/- 2:57 hr and 51 +/- 9 min. Mean total operative time was 7.5 hr. Posttransplant mean peak alanine aminotransferase and aspartate aminotransferase levels were 937.3 +/- 703.1 IU/L and 923.3 +/- 708.5 IU/L, respectively. Mean prothrombin time on postoperative day 2 was 14.9 +/- 1.6 sec. Average total bilirubin on postoperative day 5 was 4.9 mg/dl. Median length of stay in the intensive care unit was 4 days. One recipient had poor early graft function; two recipients had primary nonfunction. Mean follow-up was 503 days (range, 110-1714 days). Three-month actual graft and patient survival rates were 85% and 91%, respectively. One-year actuarial graft and patient survival rates were also 85% and 91%, respectively. We conclude that older livers can be used safely. Advanced donor age should not be a contraindication to liver procurement.

Adult↗
PubMed1996

Nosocomial infections with vancomycin-resistant Enterococcus faecium in liver transplant recipients: risk factors for acquisition and mortality.

The risk factors for acquisition of and mortality due to nosocomial infection with vancomycin-resistant Enterococcus faecium (VREF) in orthotopic liver transplant (OLT) recipients were studied at a tertiary care hospital; 32 VREF-infected OLT patients (cases) were compared with 33 randomly selected OLT recipients (controls). More antibiotics were administered preoperatively to cases (mean, 4 antibiotics per patient for 474 antibiotic-days) than to controls (mean, 1.8 antibiotics per patient for 131 antibiotic-days). Cases were more likely than controls to have received vancomycin therapy preoperatively and to have been hospitalized in the intensive care unit (ICU) preoperatively. Logistic regression revealed that the risk factors for acquisition of VREF infection were surgical reexploration and a prolonged stay in the surgical ICU postoperatively. In the cases, the risk factors for mortality were admission to the ICU preoperatively and hemodialysis. The mortality rate associated with polymicrobial bloodstream infections was 100% despite appropriate therapy. Sixteen and 18 cases received parenteral chloramphenicol and doxycycline, respectively, for treatment of VREF infection. There were no hematologic adverse effects attributed to chloramphenicol treatment. DNA analysis of selected E. faecium isolates suggested that infections were due to multiple clones. In summary, the source of VREF infection in OLT patients is the gastrointestinal tract. Antibiotic selective pressure may contribute to colonization. Infection with VREF is a predictor of morbidity and mortality in OLT patients.

Anti-Bacterial Agents↗
PubMed1996

Resection of benign hepatic lesions with selective use of total vascular isolation.

BACKGROUND: The main morbidity associated with hepatic resection is related to excessive blood loss. Total vascular isolation (TVI) may be used to minimize blood loss in difficult hepatic resection cases. STUDY DESIGN: We reviewed our criteria for use of TVI and our experience in 43 patients who underwent hepatic resection for benign lesions between January 1990 and January 1995. Total vascular isolation was used in 23 patients; 20 resections were performed without TVI. RESULTS: We found TVI particularly useful for resection of highly vascular lesions, and lesions located centrally or adjacent to major vessels. The use of TVI reduced blood loss in difficult hepatic resections; transfusion requirements for these patients were similar to requirements for the resection of peripheral lesions. Fewer complications directly related to hepatic resection were encountered in the TVI group. CONCLUSIONS: Appropriate use of TVI will improve results after difficult hepatic resections and allow maximal sparing of normal hepatic tissue when operating on benign lesions.

Adolescent↗
PubMed1995

Successful use of an enhanced immunosuppressive protocol with plasmapheresis for ABO-incompatible mismatched grafts in liver transplant recipients.

Graft and patient survival rates after transplantation of ABO-incompatible liver allografts have been poor. We used plasmapheresis and a potent immunosuppressive regimen to control hemagglutinin levels and prevent early rejection. Ten patients who had a United Network for Organ Sharing status of 4 received ABO-incompatible allografts. Quadruple immunosuppression consisted of OKT3, Cytoxan, cyclosporine, and steroid taper; prostaglandin E-1 was administrated intravenously the first week. All patients underwent perioperative plasmapheresis to maintain hemagglutinin levels < 1:16. Patient survival was 80%; graft survival was 60% at 140-505 days. The rejection rate was 90%. Three recipients (A1-->O) lost their grafts to severe rejection at 5, 12, and 30 days after transplantation. All 3 had pretransplantation hemagglutinin levels > or = 1:100. Elevated hemagglutinin levels preceded the diagnosis of severe acute cellular rejection; plasmapheresis failed to lower anti-A titers in these 3 patients. We conclude that in an urgent setting, lowering of preformed hemagglutinins via plasmapheresis in combination with quadruple induction immunosuppression allows liver transplantation across ABO barriers. In patients with high baseline levels of preformed hemagglutinins, the risk of subsequent graft loss may be increased and transplantation with an ABO-incompatible graft may serve as a lifesaving intermediate step.

ABO Blood-Group System↗
PubMed1995

N-acetylcysteine ameliorates reperfusion injury after warm hepatic ischemia.

Glutathione is important in cellular defense against oxidative stress. We postulated that administration of N-acetylcysteine (NAC), a glutathione precursor, might help maintain or replenish hepatic glutathione stores, thereby reducing reperfusion injury in liver grafts after warm ischemia. Eighteen pigs were subjected to 2 hr of warm hepatic ischemia and divided into a control group (group A, n = 6), a preischemia treatment group (group B, n = 6: NAC, 150 mg/kg, continuous i.v. infusion 1 hr before ischemia), and a postischemia treatment group (group C, n = 6: NAC, 150 mg/kg continuous i.v., begun 20 min before reperfusion and continued for 1 hr). At initiation of laparotomy, we measured hepatic levels of reduced glutathione (GSH), its oxidized form (GSSG), ATP, aspartate aminotransferase (AST), and lactate dehydrogenase (LDH). Before reperfusion, after 2 hr of warm ischemia, GSH, GSSG, and ATP were measured. One hour after reperfusion, we measured GSH, GSSG, ATP, AST, and LDH. Bile output was recorded every 10 min. Postoperfusion AST and LDH were significantly lower in both treatment groups than in controls. In group B, hepatic glutathione was maintained at significantly higher levels than in controls, even after ischemia (P < 0.05). In group C, although hepatic GSH levels fell until reperfusion, after administration of NAC, hepatic GSH reached the level of the preischemia treatment group. In both treatment groups, GSH 1 hr after reperfusion was significantly higher than in the controls (P < 0.01): regeneration of glutathione was seen in all 6 animals in group C, compared with 2/6 in group B and none in the control group. ATP recovery, bile output, and survival were all better in the treatment groups than in the control group. Pretreatment with NAC helps maintain hepatic glutathione during warm ischemia; given after ischemia, NAC is effective in replenishing depleted glutathione stores. Adjunctive use of NAC was associated with improved glutathione homeostasis, improved bile output and ATP regeneration, and increased survival.

Acetylcysteine↗
PubMed1995

CA19-9 does not predict cholangiocarcinoma in patients with primary sclerosing cholangitis undergoing liver transplantation.

The results of liver transplantation in patients with cholangiocarcinoma have been poor. It has been suggested that elevated serum CA19-9 levels predict cholangiocarcinoma in patients with primary sclerosing cholangitis. We analyzed the predictive value of CA19-9 antigen as a marker of cholangiocarcinoma in patients with primary sclerosing cholangitis evaluated for liver transplantation. We reviewed the charts of 26 patients with primary sclerosing cholangitis (stage IV) in whom preoperative serum CA19-9 levels were determined; 22 of 26 underwent liver transplant. Explant specimens were serially sectioned and examined for tumor. In 3 of the 26 patients, cholangiocarcinoma was diagnosed during pretransplantation evaluation; exploratory laparotomy on the last patient showed no evidence of cholangiocarcinoma, and this patient is awaiting transplantation. Twelve of the 26 patients had CA19-9 levels more than double the laboratory reference range (0-37 U/mL) (mean 183.1 +/- 103 U/mL, range 77-415 U/mL). Two of the 12 patients with elevated CA19-9 levels had cholangiocarcinoma. Of the 14 patients with normal levels, two had cholangiocarcinoma. No correlation between elevated CA19-9 and bile duct dysplasia was noted. Sensitivity for serum CA19-9 levels more than twice the reference range is 50%, specificity is 54.5%, positive predictive value is 16.6%. An elevated serum CA19-9 level in a patient with stage IV primary sclerosing cholangitis does not reliably predict coexisting cholangiocarcinoma. Persistently high or rising serum CA19-9 levels do not indicate more urgent need for liver transplantation.

Adult↗
PubMed1995

Loss of speech after orthotopic liver transplantation.

Alteration of speech is a rare but distressing complication of orthotopic liver transplantation (OLT). We describe a characteristic speech disorder identified in a large series of consecutive patients undergoing OLT. Between 1988 and 1993, 525 adults underwent OLT. For all recipients with neurologic complications, we reviewed clinical findings, imaging and electrophysiologic test results, and perioperative laboratory data. Five patients (ages 23-52; UNOS status 3-4) exhibited a characteristic pattern of stuttering dysarthria, leading to complete loss of speech production, occasionally with elements of aphasia. In four of the five patients, right-sided focal seizures were subsequently noted. All cases presented within the first 10 postoperative days and improved with 1 month of cessation of cyclosporin (CyA), although halting, monotonous speech was evident to some degree in all five for up to 1 year. There was no correlation between onset of symptoms and CyA levels. None of the patients has clinical or radiologic findings suggestive of central pontine myelinolysis or akinetic mutism. EEGs and Spect scan results were consistent with dysfunction in the left frontotemporoparietal regions of the brain. A characteristic speech disorder, which may be described as cortical dysarthria or speech apraxia, occurs in approximately 1% of adults undergoing OLT. Prompt recognition of this syndrome and temporary cessation of CyA therapy may favorable affect the course.

Adult↗
PubMed1995

High-dose acyclovir and intravenous immune globulin reduce the incidence of CMV disease after liver transplantation.

We attempted to prevent cytomegalovirus (CMV) disease in liver transplant (LTx) recipients by means of a combined prophylaxis regimen consisting of high-dose acyclovir (HDA) and immune globulin (IVIG). In 259 consecutive patients, HDA was given for 3 months post-LTx; recipients seronegative for CMV also received IVIG. The previous 94 patients comprised our control group; in this group, low dose acyclovir was given to prevent herpes, and prophylaxis of CMV consisted of IVIG given only to seronegative recipients of seropositive donors. The overall incidence of CMV disease was lower in the HDA group (10.8%) than in the control group (27.6%); (P < 0.001). The CMV disease rate associated with primary exposure was 26.3% in the HDA group and 83.3% in the control group (P < 0.001). The incidence of CMV disease occurring after acute rejection was 9.5% in HDA patients and 24.6% in controls (P < 0.005) The HDA protocol was associated with a trend toward a lower incidence of CMV in patients requiring OKT3 therapy (16.7% vs 29%). High-dose acyclovir/IVIG thus reduces the incidence of CMV disease in seronegative recipients after LTx and lowers the risk of CMV disease associated with therapy for rejection.

Acyclovir↗
PubMed1995

Etiology of chronic renal failure in Turkish children.

The etiology of chronic renal failure (CRF) was studied in 459 Turkish children (205 girls, 254 boys) for the period January 1979-December 1993. Their mean age at onset of CRF was 9.5 +/- 4.2 years (range 1-16 years); CRF was defined as a glomerular filtration rate (GFR) below 50 ml/min per 1.73 m2 for at least 6 months. When a GFR determination was not available, the serum creatinine concentration was used: greater than 1 mg/dl for children aged 1-3 years, greater than 1.5 mg/dl for those 3-10 years and greater than 2 mg/dl for those 10-16 years. Primary renal disorders were as follows: reflux nephropathy 32.4% glomerular diseases 22.2%, hereditary renal disorders 11.4%, amyloidosis 10.6%, urinary stones 8% and other renal disorders 15.4%. Twenty-three cases of reflux nephropathy (15.4%) were associated with neural tube defects (NTD) and 20 (13.4%) were caused by infravesical obstruction. CRF caused vesicoureteral reflux associated with NTD and amyloidosis are more frequent in our series compared with west European and Nordic countries.

Adolescent↗
PubMed1995

Causes of increased renal medullary echogenicity in Turkish children.

The primary disorders of 50 children with increased renal medullary echogenicity on renal ultrasound were studied; 28 girls and 22 boys aged from 1 month to 16 years were classified into four groups based on underlying disease and ultrasound findings. Group 1 was composed of 17 patients with distal renal tubular acidosis (34%); intense echoes throughout the pyramid were predominant. Group 2 consisted of 14 patients with vitamin D toxicity (28%) and an intense echogenic rim around the pyramids. Group 3 included 10 patients with different types of tubulopathies. A slight hyperechogenic rim around the sides and tip of the medullary pyramids was detected. Group 4 was made up of 9 patients with rare underlying conditions. Abdominal X-rays detected medullary calcinosis in only 12 (24%) of the total 50 patients. Ultrasonography appears to be an important tool in the early diagnosis of increased renal medullary echogenicity and medullary nephrocalcinosis.

Acidosis, Renal Tubular↗