Ahmed Zidan - Academia.edu (original) (raw)

Papers by Ahmed Zidan

Hepatoma Research, 2022

The application of minimally invasive liver surgery (MILS) in the field of living donor hepatecto... more The application of minimally invasive liver surgery (MILS) in the field of living donor hepatectomy has been exceedingly slow, and its impact is limited to a handful of centers worldwide. Widespread adoption has been primarily hampered by the technical limitations of laparoscopy, namely rigid instrumentation, suboptimal optics, and a seemingly steep learning curve. These deficiencies are magnified in the donor hepatectomy operation wherein the parenchyma and vasculature must be handled atraumatically to produce a pristine allograft fit for implantation. Donor safety concerns and medicolegal ramifications are also cited as impediments to MILS in donor surgery. In 2013, our institution embraced a purely laparoscopic approach to living donor left lateral sectionectomy, and it quickly became our default technique. However, with donor hemi-hepatectomy, we gravitated to the robotic surgical system as our preferred modality. Herein, we describe our experience with minimally invasive donor ...

HPB Surgery, 2018

Objective. We are trying to investigate the possibility, safety, and benefits of replacing the ro... more Objective. We are trying to investigate the possibility, safety, and benefits of replacing the role of T-tube by another more safe and effective procedure for biliary decompression in the case of common bile duct (CBD) exploration. Methods. Our present study includes fifty consecutive patients who underwent a traditional CBD exploration due to choledocholithiasis. Patients were divided into 2 equal groups. In the 1st group, a spontaneously expelled Nelaton tube is placed in the CBD to aid in bile drainage to the duodenum, while in the 2nd group, a conventional T-tube is placed to decompress the CBD in the early postoperative (PO) days to a drainage bag. Operative and PO data as well as PO hospital stay time were recorded. All data were collected and statistically analyzed. Results. The mean operative time and PO hospital stay days were significantly low (p value < 0.05) in the Nelaton tube drainage group compared with the T-tube drainage group. On the other hand, the mean time ne...

Transplant immunology, Feb 16, 2017

The aim of the present study was to investigate association of serum amino (AA) acids and metabol... more The aim of the present study was to investigate association of serum amino (AA) acids and metabolites of AAs with post-transplant outcome in liver transplant recipients. Eighty-nine patients with end-stage liver diseases and available pre- and early post-transplant serum were characterised as patients with (GI) and without one-year mortality (GII) and patients with and without early graft dysfunction (EAD). A panel of pre- and early post-transplant serum levels of AAs and early and metabolites of tryptophan were measured using tandem mass spectrometry. Patient groups had significantly higher pre-transplant serum levels of phenylalanine, tryptophan, and tryptophan metabolites than healthy controls (for all p<0.001). Pre-transplant serum levels of all these parameters were significantly higher in GI than in GII (for all p<0.001). GI had a higher MELD score and re-transplantation number than GII (p≤0.005 for both investigations). Serum bilirubin on day 5 and serum phenylalanine o...

Implication for health policy/practice/research/medical education: This review will demonstrate t... more Implication for health policy/practice/research/medical education: This review will demonstrate the epidemiological pattern and distribution of HBV and HCV and clarify their roles as risk factors to HCC, with the consequence of HCC distribution throughout the world. Context: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections constitute a major global health problem. About 60,000 and 350,000 deaths occur as the results of HBV and HCV infections, respectively. Chronic hepatitis B and C infections are leading causes of cirrhosis and hepatocellular carcinoma (HCC) which are considered as the third cancer-associated cause of deaths worldwide. Iran suffers from the same problem but to a lesser extent as it is considered as a low endemic area for HBV and HCV infections and also as a low incidence area of HCC. This study was conducted to assess and provide a clear picture about epidemiology of HBV and HCV infections in Iran and worldwide, with the consequence on HCC distribution...

Annals of transplantation, Jan 8, 2018

BACKGROUND The Model for End-Stage Liver Disease (MELD) score is a well-established tool for asse... more BACKGROUND The Model for End-Stage Liver Disease (MELD) score is a well-established tool for assessing hepatic failure. The present retrospective study investigated whether serum keratin 18 (M65) and caspase-cleaved cytokeratin (M30) were associated with liver dysfunction and post-transplant graft failure. MATERIAL AND METHODS A total of 147 patients with liver cirrhosis were categorized into 2 groups according to their baseline MELD score (group I: MELD score <20, n=87, and group II: MELD score ≥20, n=60). Serum M65 and M30 levels were measured by ELISA. RESULTS Cirrhotic patients had significantly higher serum M65 and M30 levels than healthy controls (p<0.0001). Serum M65 was correlated with the MELD score and serum bilirubin (p≤0.007) and serum M30 was correlated with the MELD score, international normalized ratio, and serum bilirubin (p≤0.001). Group II had significantly higher serum M65 and M30 levels than group I (M65, p=0.025 and M30, p<0.001). Patients who lost the ...

International Journal of Surgery Case Reports, 2016

INTRODUCTION: Pancreatic resection is the only effective treatment with prolonged survival in ope... more INTRODUCTION: Pancreatic resection is the only effective treatment with prolonged survival in operable pancreatic cancer and peri-ampullary cancer; it is also a procedure of significant morbidity and complications. Vascular injury is one of the most serious intraoperative complications. PRESENTATION OF CASE: We report here a case of common hepatic artery injury during pancreaticodudenectomy followed by complete thrombosis after its repair. As common hepatic artery is the only arterial blood supply of the liver, acute liver failure and necrosis were the usual course. Surprisingly liver enzymes and bilirubin start to improve in post operatively due to small hardly detected accessory left and middle hepatic artery. DISSCUSSION AND CONCLUSION: Although hepatic artery is the only arterial supply of the liver, occasionally small accessory arteries may give significant arterial blood supply. In such a situation liver enzymes act as surrogate markers to assess the sufficiency of this flow to the liver.

The Annals of The Royal College of Surgeons of England, 2015

Giant liver haemangiomas are usually asymptomatic with normal liver function, which makes the cou... more Giant liver haemangiomas are usually asymptomatic with normal liver function, which makes the course long and uneventful. The most commonly reported complications of giant haemangiomas are rupture with intraperitoneal haemorrhage that is either traumatic or non-traumatic, consumption coagulopathy, Budd–Chiari syndrome and congestive heart failure. We describe the first reported complications of a giant liver haemangioma as a fistula between the haemangioma and the gastrointestinal tract.

Hepatitis Monthly, 2012

This review will demonstrate the epidemiological pattern and distribution of HBV and HCV and clar... more This review will demonstrate the epidemiological pattern and distribution of HBV and HCV and clarify their roles as risk factors to HCC, with the consequence of HCC distribution throughout the world. Context: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections constitute a major global health problem. About 60,000 and 350,000 deaths occur as the results of HBV and HCV infections, respectively. Chronic hepatitis B and C infections are leading causes of cirrhosis and hepatocellular carcinoma (HCC) which are considered as the third cancer-associated cause of deaths worldwide. Iran suffers from the same problem but to a lesser extent as it is considered as a low endemic area for HBV and HCV infections and also as a low incidence area of HCC. This study was conducted to assess and provide a clear picture about epidemiology of HBV and HCV infections in Iran and worldwide, with the consequence on HCC distribution all over the world including Iran, and to analyze current literature regarding the modes of transmission and risk factors of HBV and HCV infections. Evidence Acquisition: In this review, we performed electronic and manual searches on available databases such as MEDLINE, PubMed, Ovid, Embase, and the Iranian databases such as IranMedex. We also performed a Google search to find related articles. Results: HBV and HCV infections are the most common risk factors of hepatocellular carcinoma. The epidemiology of HCC usually follows that of HBV and HCV infections. With the introduction of HBV national vaccine in Iran and worldwide, there is a noticeable effect on reduction in HBV prevalence in most countries, and we expect that HCV will replace HBV as a major risk factor of HCC in Iran and worldwide. Alcohol plays a minor role as a risk factor for cirrhosis and HCC in Iran, Asia, and Africa, despite its noticeable role in Europe and the USA. Conclusions: Vaccination against HBV remains the most effective approach against HBV infection with consequence decrease in HBV-related HCC. There is a need to improve the awareness about epidemiology of HBV and HCV infections, modes of transmission, and their complications, specifically HCC among population.

Annals of Saudi Medicine, 2019

Einleitung: Durch den steigenden Mangel an Spenderorganen in Mitteleuropa werden zur Zeit vor all... more Einleitung: Durch den steigenden Mangel an Spenderorganen in Mitteleuropa werden zur Zeit vor allem Patienten mit sehr hohen lab-MELD-Scores transplantiert. Dies wird durch einen Anstieg der Wartezeit weiter verkompliziert. Ziel dieser Studie war eine Analyse von Patienten, die mit einem lab-MELD >[for full text, please go to the a.m. URL]

Experimental and Clinical Transplantation, 2019

OBJECTIVES Liver retransplant is considered the only hope for patients with irreversible graft fa... more OBJECTIVES Liver retransplant is considered the only hope for patients with irreversible graft failure after primary transplant. In most Western centers, retransplantis done mainly from deceased donors; so far, only few published studies have reported on outcomes of liver retransplant with living donors. In this study, our aim was to analyze the outcomes of living-donor liver retransplant. MATERIALS AND METHODS Patients who underwent liver retransplant between February 2011 and February 2019 were included in the study. Preoperative, operative, and postoperative data were analyzed. Results from 2 patient groups were compared: liver retransplant with living donors and liver retransplant with deceased donors. RESULTS Thirty-two patients underwent liver retransplant (21 adult and 11 pediatric patients). The most common indications for liver retransplant were hepatic artery thrombosis (28.5%) and primary graft nonfunction (23.8%) in adults and hepatic artery thrombosis (45.5%) and chronic rejection (36.4%) in pediatric patients. Seventeen retransplant patients (53.1%) required early retransplant (within 1 mo), mainly due to hepatic artery thrombosis (52.9%) and primary graft nonfunction (35.3%). Late retransplant was mainly due to chronic rejection (40%) and recurrence of primary disease (26.7%). Seventeen patients (53.1%) underwent living-donor retransplant, and 5 donors underwent robotic right hepatectomy. Graft and patient survival rates at 1, 3, and 5 years were 81.3% for living-donor and 51.4% for deceased-donor liver retransplant recipients (P = .08). On multivariate analyses, we observed significant differences between both groups in pretransplant Model for End-Stage Liver Disease and Pediatric End-Stage Liver Disease scores (P = .05), preoperative international normalized ratio (P = .012), and cold ischemia time (P = .046). CONCLUSIONS The use of living donors for liver retransplant, despite its technical demand, was shown to be a safe and feasible option, especially when there is scarcity of deceased donors.

International Journal of Surgery Open, 2016

Introduction: Caroli syndrome is characterized as multiple cystic or saccular dilatations of intr... more Introduction: Caroli syndrome is characterized as multiple cystic or saccular dilatations of intrahepatic bile ducts (Caroli disease) and congenital hepatic fibrosis. Diagnosis depends on histological features and imaging, which shows communications between the sacculi and bile ducts. Presentation of a case: In our case, the patient had segments II/III liver resection six years ago for Caroli syndrome. A follow-up CT after four months of the operation revealed remnant cysts in segment IV, which needed another surgical intervention to resect the remnant cysts and segment IV after six years from the first operation. Disscussion: In our case, we were surprised that patient has remnant of the primary benign disease in the follow-up CT after only four months of the previous operation. This remnant continued to increase in size with recurrent attacks of cholangitis until liver abscess developed and required another surgical intervention. Conclusion: Imaging is essential in planning the operative treatment to detect the extent of the Caroli disease and define the extent of resection. Any residual disease due to inappropriate imaging planning may cost the patient another cycle of suffering and may need another surgical intervention as in our case. We recommend using intraoperative ultrasound for accurate determination of the line of resection.

Frontiers in Transplantology, 2016

Liver transplantation is the most effective treatment for the patients with acute liver failure o... more Liver transplantation is the most effective treatment for the patients with acute liver failure or end-stage liver diseases. Liver transplantation is also indicated for patients with hepatocellular carcinoma to yield a best result if the tumor/tumors meet Milan criteria, University of California San Francisco(UCSF) criteria, or up-to-seven criteria. It is no doubt that more and more people need liver transplantation to save their lives. However, liver donation is always short to match the demand of liver transplantation. Therefore, how to expand the donor pool to increase the opportunities of liver transplantation is paramount. Splitting liver is one of the ways to expand the donor pool and offers an additional chance of liver transplantation. At the beginning of split liver transplantation (SLT), the liver was split and transplanted to an adult and a child. Now, the liver can be split into full right and left lobes and transplanted to two adults. When split liver transplantation is to be performed, there are many considerations that should be clarified. With the improvement of surgical skill, the outcomes of split liver transplantation are similar to that of deceased whole liver transplantation. It is worth to promote the policy of split liver transplantation.

Human immunology, Jan 27, 2016

Early allograft dysfunction (EAD) after liver transplantation is mostly a reversible event caused... more Early allograft dysfunction (EAD) after liver transplantation is mostly a reversible event caused by factors related to ischemia/reperfusion (I/R) injury. EAD represents a hepatic injury associated with pre- and early post-transplant inflammatory cytokine responses. Aim of the present study was to evaluate the prognostic and diagnostic value of CRP in liver transplant recipients with EAD. Forty-seven patients with EAD were compared with 115 non-EAD patients. Pre- and post-transplant parameters were analyzed. EAD was defined based on postoperative liver function tests such as INR, bilirubin and liver enzymes. Statistical analysis was performed using SPSS version 18.0. Pre-transplant liver enzyme were not significantly different in the two groups. At day 3, 5 and 10 post-transplant CRP was significantly higher in patients with EAD than in non-EAD patients (p⩽0.001 for all investigations) and remained consistently high in patients with EAD and low in non-EAD patients. EAD patients with...

Transplantation Journal, 2012

Purpose: At the time of transplantation, the recipient serum is tested with the prospective donor... more Purpose: At the time of transplantation, the recipient serum is tested with the prospective donor lymphocytes to identify specific reactivity in the donor-specific crossmatch. A positive crossmatch is a contraindication for kidney transplantation because of the higher incidence of antibody mediated rejection. However, numerous studies has found that the liver is resistant to it. We investigated the relationship between the pretransplant lymphocytotoxic crossmatch results and the long-term outcome after liver transplantation in a single center. Methods: From January 1996 to December 2010, 1021 living or deceased donor liver transplant recipients were included. Their medical records and pretransplant crossmatch results were collected. Results: 69 of 1021 (6.8%) liver transplants were performed with a positive crossmatch and their outcome was compared with the remaining 952 performed with a negative crossmatch. No significant differences in rejection, biliary complication, vascular complication, primary disease recurrence and de novo malignancy were found in negative and positive T-or B-lymphocytotoxic crossmatch recipients. Graft loss and patient survival were not inferior in the recipient group testing positive crossmatch. Besides, T and B cell crossmatch against donor showed positive results initially. But recipient´s autocontrol (recipient´s cell + recipient´s serum) also showed similar positive results. After dithiothreitol(DTT) treatment, all previous positive result was converted to negative. So, IgM class autoantibody against recipient´s own antigen was strongly suggested. We defined these subpopulation as false positive crossmatch group, accounting for 41 (4.0%) recipients. Significantly high incidences of de novo malignancies, especially lymphoid malignancy including posttransplant lymphoproliferative disorder, were observed in false positive crossmatch recipients compared to those of negative controls. (P=0.018 in overall de novo malignancy, p=0.029 in lymphoid malignancy) Conclusion: This study demonstrated that the presence of circulating IgM autoantibody in the recipient may be a risk factor for de novo malignancy, specially lymphoid malignancy. Although the precise mechanism remains unclear, immunologic factors is considered to involve in the pathogenesis of de novo malignancy.