Investigation of the Association Between ITPA Gene 94C>A Sequence Variant and Kidney Transplant Rejection in Iranian Kidney Transplant Recipients

OBJECTIVES

Thiopurine prodrugs are commonly used in kidney transplant recipients. Inosine triphosphate pyrophosphatase is an enzyme encoded by the ITPA gene. Alteration of ITPA gene is one of the pharmacogenetic sequence variants possibly involved in thiopurine metabolism. The ITPA 94C>A sequence variant (C-to-A substitution at nucleotide 94) is associated with an increased risk of adverse drug reactions in patients treated with the thiopurine drug. The aim of the present study was to investigate the effect of the ITPA 94C>A gene sequence variant in kidney transplant recipients.

MATERIALS AND METHODS

The genotyping of the ITPA rs1127354 variant was performed by the polymerase chain reaction restriction fragment length polymorphism method in 140 kidney transplant recipients and in 100 control participants. Data were analyzed with SPSS statistical software.

RESULTS

The results revealed a significant difference between control and nonrejection groups regarding the rs1127354 genotype and allele frequency. No significant difference was found between the rejection and nonrejection groups regarding the rs1127354 genotype and allele frequency. Also, a significant association was observed between the ageofthe control group and age of the rejection group. No significant differences between sex and underlying disease in patients with or without rejection were observed.

CONCLUSIONS

We observed no significant differences between rejection and nonrejection transplant. Further studies are recommended, in a larger population and with different ethnicities.

Investigation of the Association Between the ITPA Gene 94C>A Gene Sequence Variant and Liver Transplant Rejection in Iranian Liver Transplant Recipients

OBJECTIVES

Inosine triphosphate pyrophosphatase is an enzyme encoded by the ITPA gene and functions to prevent the incorporation of thiopurine nucleotides into DNA and RNA. Thiopurine drug metabolites such as azathioprine and 6-mercaptopurine have been included in the lists of inosine triphosphate pyrophosphatase substrates. Inosine triphosphatase gene alterations are other pharmacogenetic sequence variants possibly involved in thiopurine metabolism. This study aimed to evaluate the possible association between ITPA 94C>A gene sequence variant (C-to-A substitution at nucleotide 94) in liver transplant recipients.

MATERIALS AND METHODS

The genotyping of ITPA 94C>A was evaluated by the polymerase chain reaction- restriction fragment length polymorphism method in 200 liver transplant recipients as well as 100 controls. Data were analyzed with SPSS statistical software.

RESULTS

This study showed statistically significant associations between the CA genotype of the ITPA 94C>A sequence variant and liver transplant in the rejection and nonrejection groups. Moreover, the results reported in this study showed no significant differences between sex, age, and blood group in patients with liver transplant (with or without transplant rejection).

CONCLUSIONS

Our results indicated that there were statistically significant associations of the CA genotype of ITPA 94C>A sequence variant with liver transplant in the rejection and nonrejection groups. Further studies are recommended.

Bacterial infections in the early period after liver transplantation in adults: A prospective single-center cohort study

Liver transplantation (LT) is a potentially curative treatment for terminal stage hepatic diseases. Bacterial infections are the main causes of mortality and morbidity in the early period after LT. Identifying the risk factors could help in minimizing their development. We prospectively investigated the incidence, characteristics, and risk factors of bacterial infections among the recipients during hospitalization after LT and assigned a predictive score. All 389 consecutive adults who underwent LT at the main referral hospital of LT in Iran during 1 year were enrolled prospectively in a cohort study. Infection group consisted of 143 recipients (36.8%). Urinary tract and surgical site infections were the most frequent ones. Gram-negative bacteria were more prevalent than Gram-positive ones. Independent risk factors were female sex (relative risks = 2.13), age ≤ 43.5 years (3.70), hospital stay ≥ 9.5 days (5.22), abdominal reoperation (3.03), vancomycin-resistant Enterococci colonization (5.52), hospitalization 3 months prior to LT (3.25), mechanical ventilation ≥48 hr (4.93), and renal replacement therapies (13.40). We developed a risk score for the prediction of bacterial infections with an area under the receiver operating characteristic curve of 0.85 (95% CI, 0.81-0.89) with sensitivity of 88% and specificity of 64%. In the infection group, mortality was higher than in controls (18.9% vs. 2.0%) with longer hospitalization (16 vs. 10 days; P < 0.001). We detected a high rate of bacterial infections leading to longer hospital stay and higher mortality rate. The formulated risk score can help predict bacterial infections; however, it requires clinical validation in further studies.

Significance of Occult Hepatitis C Virus Infection in Liver Transplant Patients With Cryptogenic Cirrhosis

OBJECTIVES

Investigations into the viral causes of end-stage liver disease in liver transplant patients with cryptogenic underlying disease remain of interest. Hepatitis C virus infection, especially in its silent (occult) form, may play a key role in the introduction and development of cryptogenic cirrhosis. We aimed to determine the prevalence of occult hepatitis C virus infection in liver transplant recipients with cryptogenic cirrhosis.

MATERIALS AND METHODS

In this cross-sectional study, 127 liver transplant recipients confirmed to have cryptogenic cirrhosis were included. Plasma samples of the patients underwent evaluation for hepatitis C virus antibody using the enzyme-linked immunosorbent assay method. Plasma samples and paraffin-embedded liver tissue samples were tested for hepatitis C virus RNA using nested reverse transcriptase-polymerase chain reaction.

RESULTS

Hepatitis C virus RNA was detected in liver tissue sections of 10 patients (7.9%). However, none of the cryptogenic patients had hepatitis C virus RNA or antibody in their plasma samples. None of the patients had hepatitis C or G virus coinfection, but simultaneous detection of hepatitis B and hepatitis C virus was diagnosed in 4 liver tissue samples.

CONCLUSIONS

A finding of hepatitis C virus RNA in liver tissue samples of transplant recipients presents the historical possibility of occult hepatitis C virus infection as underlying disease in our patients with cryptogenic cirrhosis. Results present an important and determinative role of occult hepatitis C virus infection in the pathogenesis of cryptogenic cirrhosis, which needs further confirmation in additional studies.

Evaluation of Interleukin-21, 23 and 27 mRNA Expression and Protein Level in Liver Transplant Patients

Cytokines have prominent roles in activating of different T cells and shifting the immune response, in this study the role of three cytokines (IL-21, IL-23 and IL-27) is investigated in the liver transplant rejection. Three EDTA-treated blood samples were collected from each liver transplanted patient in 1st, 4th and 7th day of post-transplantation. The expression level of the mentioned cytokines was determined using real-time PCR for all samples. Also, the serum levels of cytokines were determined using ELISA tests. In acute rejection (AR) group (51 patients), mRNA expression pattern of IL-21and IL-23 showed a steady increase, but this pattern was converse for IL-27. Our results in non-acute rejection (non-AR) group (54 patients) showed an elevation in day 4 and then a decrease in day 7 for IL-21 and IL-23 genes. This pattern was converse again for IL-27 gene. In comparison between the two groups, in all 3 sampling times the mean of mRNA expression level of IL-21 and IL-23, showed an increase in AR group which this increase was significant for IL-21 in the 3rd (p=0.007) and for IL-23 in 2nd (p=0.048) and 3rd (p=0.049) sampling time, but the pattern of mRNA expression for IL-27 was contrary to the results of IL-21 and IL-23. Furthermore, ELISA technique also, showed the serum level changes the same as cytokines. In this study IL-21 and IL-23 showed pro-inflammatory properties in the liver transplant rejected patients. Also, IL-27 having different expression pattern, showed anti-inflammatory behavior which needs more considerations in future.

A New Consideration in Hepatic Artery Reconstruction in Adult Liver Transplant: Arterial Transposition Versus Extra-Anatomic Jump Grafts

OBJECTIVES

In some cases of liver transplant, standard hepatic artery reconstruction may be difficult or impossible due to inadequate flow of the recipient's hepatic artery, as a result of stenosis, intimal dissection, or anomalies of the hepatic artery. We compared splenic artery transposition with extra-anatomic jump graft as 2 alternative methods for hepatic artery reconstruction in these situations.

MATERIALS AND METHODS

We reviewed the files of 2135 liver transplant recipients from March 2011 to February 2016 at the Shiraz Transplant Center. Data of 93 patients with unusual hepatic artery reconstruction were analyzed to assess outcomes, morbidity, mortality, and pre- and posttransplant parameters (both clinical and paraclinical). Patients were divided into 2 groups: 17 with splenic artery transposition (splenic artery group) and 76 with extra-anatomic jump grafts (control group).

RESULTS

There was only 1 occurrence (5.8%) of hepatic artery thrombosis in the splenic artery group causing extra-anatomic jump graft. However, in the control group, there were 4 occurrences (5.2%) of hepatic artery thrombosis, causing 1 revision of anastomosis and 3 retransplant procedures. No deaths due to hepatic artery complications were reported in the 2 groups. Three-year survival rate was 87.5% in the splenic artery group and 68.9% in the control group.

CONCLUSIONS

Splenic artery transposition is an acceptable method for hepatic artery reconstruction in deceased-donor liver transplant procedures with no greater rates of complication or morbidity than extra-anatomic jump grafts. Less operation time and better exposure during surgery are advantages of this method.

Urinary Tract Infections Among Hospitalized Adults in the Early Post-Liver Transplant Period: Prevalence, Risk Factors, Causative Agents, and Microbial Susceptibility

OBJECTIVES

Urinary tract infections are among the most common infections after liver transplant, especially soon after surgery. This study analyzed urinary tract infections or bacteriuria, their causative agents, and related risk factors in the early period after liver transplant in hospitalized adult transplant recipients in the main liver transplant referral center in Iran.

MATERIALS AND METHODS

In this prospective study, 389 consecutive adult patients who underwent liver transplant at the Nemazee Teaching Hospital were enrolled between October 2014 and October 2015. Risk factors were compared for patients who developed urinary tract infections or bacteriuria ("infection group "; n = 63 [16.2% ]) and patients without evidence of infection ("control group "; n = 211 [54.2% ]). Patients with sites of infection other than the urinary tract were excluded. Antimicrobial sus ceptibility testing was performed using the Kirby-Bauer disk-diffusion method. Univariate and multivariate analyses compared variables between the 2 groups.

RESULTS

Seventy-nine episodes of urinary tract infections or bacteriuria occurred in the infection group. Multiple logistic regression analysis showed that female sex, hospitalization 2 to 7 days before transplant, and frequency of abdominal exploration were 11.0, 5.9, and 3.0 times more common in the infection group than in the control group. The chance of infection rises 1.1 times with each one unit increase of body mass index. The most common infection causes were gram-negative bacteria (n = 50; 63.3%), predominantly Escherichia coli (n = 24; 30.4%); followed by gram-positive bacteria (n = 20; 25.3%), predominantly Enterococcus species (n = 14; 17.8%) that had a high incidence of vancomycin resistance (n = 10; 71.4%); and non-Candida albicans species isolates (n = 9; 11.4%).

CONCLUSIONS

Urinary tract infections are a common infection in hospitalized adult patients soon after liver transplant. Female sex, hospitalization shortly before transplant, more frequent abdominal exploration, and higher body mass index substantially increased the risk of developing such infections in this period.

Experience of Liver Transplant in Patients Diagnosed with Budd-Chiari Syndrome

OBJECTIVES

Budd-Chiari syndrome can lead to fulminant hepatic failure and cirrhosis. The treatment depends on the severity of disease. Liver transplant is a successful treatment option for those with advanced-stage disease.

MATERIALS AND METHODS

In this retrospective study, we analyzed all liver transplants conducted for Budd-Chiari syndrome at the organ transplant unit of Shiraz University of Medical Sciences, Iran, from 1993 to January 2016. Overall, 3201 liver transplant procedures were performed. Among these, 68 presented with Budd-Chiari syndrome.

RESULTS

The median age was 31 years among 27 male and 41 female patients. Five patients received pretransplant interventions, with 2 treated with inferior vena cava stenting and 3 having transjugular intrahepatic portosystemic shunts. Sixty-five patients with Budd-Chiari syndrome received deceased-donor grafts and 3 received living-donor grafts. Among the Budd-Chiari transplant patients, 6 patients died. Five deaths occurred in the early posttransplant period, and 1 patient retransplanted after 2 years for recurrence of disease died due to graft failure. The five-year survival rate was 89% among patients with Budd-Chiari syndrome.

CONCLUSIONS

Liver transplant along with posttransplant anticoagulation therapy can improve the survival of patients with advanced-stage Budd-Chiari syndrome.

Antibiotic selective pressure and development of bacterial resistance detected in bacteriuria following kidney transplantation

INTRODUCTION

Bacteriuria (symptomatic and asymptomatic) is the most common infectious complication after kidney transplantation. This study aimed to determine its prevalence among kidney transplant recipients hospitalized after transplantation, respective risk factors, and frequency of isolates and antibacterial susceptibility.

METHODS

Retrospectively, we divided hospitalized patients into 3 groups. Groups 1 and 2 included 78 and 152 recipients with and without bacteriuria, respectively, and the potential risk factors were compared. Cefixime was prescribed as early postsurgical prophylaxis. Group 3 patients were 116 randomly selected nontransplantation patients with urinary tract infection. Frequency of uropathogens and their antibiotic susceptibility were compared in groups 1 and 3.

RESULTS

In total, 103 bacteriuria episodes were detected in 15.2% of the patients. The frequency of risk factors in groups 1 and 2 was similar. Escherichia coli was the most common isolate in groups 1 (40.8%) and 3 (68.1%; P = .03). Streptococcus faecalis was the most common gram-positive isolate in groups 1 (17.5%) and 3 (6.9%; P = .03). Sensitivity rates in group 1 were 9% to trimethoprim-sulfamethoxazole, 20% to ciprofloxacin, and 38.4% to gentamicin, which was not significantly different from group 3. However, the sensitivity rates of gram-negative isolates to ceftriaxone were 9.5% and 28.4% (P = .004) in groups 1 and 3, respectively, and to cefixime 4.5% and 22% (P = .01).

DISCUSSION

High antibacterial resistance of uropathogens isolated from kidney transplantation and nontransplantation patients is alarming. The higher resistance to third-generation cephalosporins in transplant recipients may be due to antibiotic selection pressure secondary to postsurgical prophylaxis with cefixime.

Liver transplantation as a definitive treatment for familial hypercholesterolemia: A series of 36 cases

FH is a genetic disorder characterized by an increase in serum LDL and total cholesterol values. The afflicted patients are at increased risk of premature atherosclerosis and myocardial infarction. Different treatment modalities are present, including pharmacological agents and surgical procedures. The most effective method of therapy in refractive cases is liver transplantation. Herein, we report our experience on 36 cases of patients with FH undergoing liver transplantation in our center, the main referral center of liver transplantation in Iran. The clinical findings, hospital courses, post-operative complications, and patient follow-up are also described.

Nutcrackerlike Phenomenon Is An Unusual Cause for Gross Hematuria After a Kidney Graft

Nutcracker phenomenon is the condition that occurs most commonly at the morphologic type by compression of the left renal vein between the aorta and superior mesenteric artery. The diagnosis is often delayed because of the variability in manifestations and absence of consensus on diagnostic criteria. We report a 30-year-old woman who presented gross hematuria several days after a kidney transplant. Nutcracker syndrome was established intraoperatively during open surgical approach for bladder clot evacuation. Renal repositioning was done with relief in the degree of hematuria intraoperatively. No episode of gross hematuria was observed on follow-up after 8 months.

Long-term survival and its related factors in pediatric liver transplant recipients of shiraz transplant center, shiraz, iran in 2012

BACKGROUND

Liver transplantation is considered as the standard treatment for both children and adults with end-stage liver diseases. Using this method, children who have no chance for life can live a much longer life .Shiraz Transplant Center is the major pediatric liver transplant center in Iran. Therefore, determining patients' survival and its effective factors can help clinical programming for increasing such patients' survival after liver transplantation.

OBJECTIVES

The present study aimed to investigate the survival of patients below-18-years-old undergoing liver transplantation and the factors affecting their survival.

PATIENTS AND METHODS

The present historical cohort study was conducted on 392 patients below-18-year-sold who had undergone liver transplantation for the first time in the Namazi hospital liver transplant center, Shiraz, Iran between 2000 and 2011. In this study, 1-, 3-, 5-, and 10-year survival of the patients was assessed using Kaplan-Meier and life table methods. The effect of factors related to the recipients, donors, and the transplantation process on the patients' survival was also investigated.

RESULTS

According to the results, 1, 3, 5 and 10-year survival of patients was 73%, 67%, 66%, and 66%, respectively. Besides, 1 ,3, 5, and 10-year survival of the patients who survived 1 and 3 months after the transplantation was 84%, 78%, 77%, and 77% and 89%, 82%, 81%, and 81%, respectively. In the univariate analysis, age, patients' weight at transplantation, initial diagnosis, PELD/MELD score, existence of post-transplant complications, and year of transplantation were found to be effective factors on the patients' survival. In the multivariate analysis, only the type of graft, PELD/MELD score, and existence of post-transplant complications were the prognostic variables.

CONCLUSIONS

In this study, the patients' survival rate was 73%, which is quite low compared to the survival rate reported in other studies. Although we only have a 12-year experience with pediatric liver transplantation, the survival rate has increased in our center through the recent years (2008-2011). However, the survival rate of the patients who had survived 3 months after the transplantation was 89% which is comparable to other studies. Overall, cholestatic diseases (biliary atresia was the most prevalent), type of transplantation (split), PELD/MELD score > 20, and existence of post-transplant complications increased the risk of death after the transplantation.

Histopathology of post-transplant liver biopsies, the first report from iran

BACKGROUND

Evaluation of a transplanted liver by Imaging techniques and enzyme changes is sensitive to hepatocellular or biliary problems, but in most instances liver allograft biopsies are performed in order to find out the final reason for these changes.

OBJECTIVES

It's been about 17 years (with more than 1326 cases) since the first liver transplantation in the Namazi Hospital of Shiraz University of Medical Sciences while during the last five years the number of post liver transplant biopsies have increased. Until now there has been no report of the pathological results of post liver transplant needle biopsies from Iran.

MATERIALS AND METHODS

During the last 5 years, there have been 382 post liver transplant biopsies. We studied the clinical charts and pathological results of all needle biopsies.

RESULTS

A total of 382 needle biopsies were performed on 287 patients aged between 1 and 64 years old. The earliest specimen was obtained within the first few hours following transplantation, and the last was gathered 3209 days (261 ± 523) post-transplantation. Acute rejection was the most common diagnosis, which occurred in 180 (47%) of specimens. Among other complications were vascular problems (8.6%), preservation/reperfusion (I/R) injury (7%), chronic rejection (5.2%), biliary injury/obstruction (3.4%), recurrence of primary disease (2.6%), drug-induced hepatic injury (1.8%), cirrhosis (1.6%), sepsis (1.4%), cytomegalovirus hepatitis (1.4%), post-transplantation lymphoproliferative disease (1%) and Venous outflow obstruction (0.5%).

CONCLUSIONS

The most common pathological diagnosis of post-transplant liver needle biopsies has been acute rejection, followed by ischemia due to hepatic artery thrombosis, preservation/reperfusion injury, and chronic rejection.

The use of micro pulse oximetery as a new detector of tissue perfusion in solid organ transplantation

Vascular complications are a frequent cause of transplant failure; angiography, duplex sonography, computerized tomography (CT) scan, CT-angiography and microdialysis are the methods that were suggested for the detection of arterial obstruction after transplantation. In this study, we suggest a new method. Eight healthy adult dogs were included in the trial. All cases were operated by the same surgeon and the liver, pancreas, spleen, kidney and bowel tissue were exposed. The probes of the device, which were designed for this study, were inserted on the organ parenchyma. The device, a neonatal pulse oximeter, has two probes that were fixed by a holder in front of each other; the distance between the probes was changeable via a spring. The pulse and the oxygen saturation of the tissue were measured initially. Following this, by inducing ischemia with vessel clamping, the pulse and the oxygen saturation were measured again. The collected data were analyzed under the supervision of a statistician. In the liver and spleen, we could not detect a clear pulse wave and oxygenation. On the other hand, in the pancreas, kidney and bowel, we detected a clear curve of oxygenation and pulse in all cases. Obstruction caused significant changes: the pulse was not detected and the oxygenation decreased significantly. Our study suggests that with early diagnosis, the surgeons can detect arterial occlusion immediately and early intervention may decrease parenchymal damage. This study is the first experience in this field, and these findings need to be validated with further studies.

Reduction of the severity of ischemia reperfusion-induced pancreatitis by ischemic pre-conditioning of the liver

Pre-conditioning by brief exposure to ischemia does not only protect the concerned organ against subsequent severe ischemic damage, but also has protective effect on other organs, which is called remote pre-conditioning. Our aim in this study was to evaluate the protective effect of brief liver ischemia on the pancreas against severe ischemia-reperfusion-induced pancreatitis. This study was performed on 30 male Wistar rats. Ischemic pre-conditioning of liver was performed by first clamping of the hepatic pedicle for 10 minutes. Following this, ischemia-reperfusion of the pancreas was performed by first clamping the inferior splenic artery for 30 minutes, followed by reperfusion for one hour. The rats were divided into three groups (10 rats in each group). Group one was the sham operated group, without clamping of any artery. Group two developed ischemia-reperfusion-induced pancreatitis, without ischemic pre-conditioning of the liver, while Group three underwent ischemic pre-conditioning of the liver followed by ischemia-reperfusion of the pancreas. Ischemic pre-conditioning, applied prior to induction of pancreatitis, caused a reduction in plasma lipase, plasma interleukin-1beta and histological signs of pancreatic damage, but plasma interleukin-10 levels were not significantly different between the three groups. Ischemic pre-conditioning of the liver did not cause any alteration of the liver enzymes. Our study suggests that ischemic pre-conditioning of the liver reduces the severity of ischemia-reperfusion-induced pancreatitis. These effects are partly related to the reduction of pro-inflammatory interleukin -1beta.

Inflammatory pseudotumor of the liver: two case reports and a review of the literature

Rare cases of inflammatory pseudotumor (IPT) in two adolescents are reported. Both of them presented with significant weight loss and were operated upon with the impression of liver abscess and malignant liver tumor. These two cases are reported to emphasize IPT of the liver as a differential diagnosis of hepatic masses in children because recognition of this condition before operation can avoid unnecessary surgery.