Liver transplantation in the Kingdom of Saudi Arabia.

The first liver transplantation (LT) in Saudi Arabia was performed in 1991; however, it was not until 1994 that the first structured LT program was launched. Until 1997, all LTs in the Kingdom of Saudi Arabia (KSA) were deceased donor liver transplantations. Programs performing LTs needed the authorization of the Saudi Center for Organ Transplantation (SCOT), which provides the essential support for organ procurement and allocation as well as regulatory support for organ transplantation in the country. Currently, there are 4 LT centers in the KSA. Three centers are in Riyadh, the capital city of KSA, and 1 is in the city of Dammam in the Eastern province. Pediatric living donor liver transplantation (LDLT) began in 1997, while the adult LDLT program started 4 years later in 2001. Currently, more than 2000 LTs have been performed by the 4 centers in the KSA. Over 50% of those were performed at King Faisal Specialist Hospital and Research Center in Riyadh. The outcomes of these transplants have been comparable with the international standards. The aim of this review is to provide an overview of LT in KSA. Liver Transplantation 23 1312-1317 2017 AASLD.

Sheep as a Model for Liver Transplantation.

OBJECTIVE: Experimental animal liver transplantation is the initial step, before the application of the procedure on humans. Canine and swine transplantation were used to perfect the technical aspects of the procedure. Small animals such as rats were mainly utilized to study the metabolic and immunological aspects of liver transplantation. In this paper, we describe our experience with attempting liver transplantation in a sheep animal model. MATERIAL AND METHOD: The animal model used for both donor and recipient was outbred male weanling sheep of Naimi strain (Ovis aries, Awassi). They weigh between 25 and 35 kg. They were put under general anesthesia. Harvested livers were kept in cold storage. Recipients underwent hepatectomy, after construction of an active portal systemic bypass using a Medtronic pump. The implantation was done with caval replacement and direct portal anastomosis. The hepatic artery with its attachments to the aortal was anastomosed directly to the recipient aorta. RESULT: Twelve pairs (24 sheep) were utilized for donor and recipient surgery. Donor surgery was completed successfully in all 12 cases. Recipient surgery was not completed in three cases, when animals were lost in the implantation phase, before reperfusion mainly due to uncontrolled bleeding, resulting in hemodynamic instability. We also lost five recipients immediately after reperfusion, mainly due to post-perfusion bleeding and hemodynamic instability. Four recipients stayed alive after the implantation. CONCLUSION: We demonstrated the feasibility of using sheep as an animal model for liver transplantation. We described the similarities of sheep liver to that of humans, as well as the technical difficulties. This model is suitable in situations where other well-established models are not available for cultural or religious reasons. Further refinement in the technical aspects will be needed, as well as investigation of the biochemical outcome and long-term survival.

Staged hepatectomy for bilobar colorectal hepatic metastases.

OBJECTIVES: This study describes the management of patients with bilobar colorectal liver metastases (CRLM). METHODS: A retrospective collection of data on all patients with CRLM who were considered for staged resection (n= 85) from January 2003 to January 2011 was performed. Patients who underwent one hepatic resection were considered to have had a failed staged resection (FSR), whereas those who underwent a second or third hepatic resection to produce a cure were considered to have had a successful staged resection (SSR). Survival was calculated from the date of diagnosis of liver metastases. Complete follow-up and dates of death were obtained from the Government of Quebec population database. RESULTS: Median survival was 46 months (range: 30-62 months) in the SSR group and 22 months (range: 19-29 months) in the FSR group. Rates of 5-year survival were 42% and 4% in the SSR and FSR groups, respectively. Fifteen of the 19 patients who remained alive at the last follow-up date belonged to the SSR group. CONCLUSIONS: In patients in whom staged resection for bilobar CRLM is feasible, surgery would appear to offer benefit.

Portal vein embolization stimulates tumour growth in patients with colorectal cancer liver metastases.

OBJECTIVES: Portal vein embolization (PVE) can facilitate the resection of previously unresectable colorectal cancer (CRC) liver metastases. Bevacizumab is being used increasingly in the treatment of metastatic CRC, although data regarding its effect on post-embolization liver regeneration and tumour growth are conflicting. The objective of this observational study was to assess the impact of pre-embolization bevacizumab on liver hypertrophy and tumour growth. METHODS: Computed tomography scans before and 4 weeks after PVE were evaluated in patients who received perioperative chemotherapy with or without bevacizumab. Scans were compared with scans obtained in a control group in which no PVE was administered. Future liver remnant (FLR), total liver volume (TLV) and total tumour volume (TTV) were measured. Bevacizumab was discontinued ≥ 4 weeks before PVE. RESULTS: A total of 109 patients and 11 control patients were included. Portal vein embolization induced a significant increase in TTV: the right lobe increased by 33.4% in PVE subjects but decreased by 34.8% in control subjects (P < 0.001), and the left lobe increased by 49.9% in PVE subjects and decreased by 33.2% in controls (P= 0.022). A total of 52.8% of the study group received bevacizumab and 47.2% did not. There was no statistical difference between the two chemotherapy groups in terms of tumour growth. Median FLR after PVE was similar in both groups (28.8% vs. 28.7%; P= 0.825). CONCLUSIONS: Adequate liver regeneration was achieved in patients who underwent PVE. However, significant tumour progression was also observed post-embolization.

The use of ex-vivo liver perfusion circuit in sheep model: Preliminary report.

OBJECTIVES: To describe a novel animal model for ex-vivo liver perfusion. METHODS: This study was carried out at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia, between September 2016 and January 2019. We assembled a perfusion circuit operated by a continuous pressure-driven arterial pump with continuous portal and arterial pressure and volume measurements. We used normothermic oxygenated perfusate. The livers used were retrieved from the sheep. RESULTS: Ex-vivo continuous perfusion of the liver was achieved for up to 9 hours with stable pressure and volume in both hepatic artery and portal vein. In 4 experiments the arterial pressure was kept in a range of 48-52 mmHg with a mean of 51.75±4.31 resulting in arterial volume at steady state of 223.5±48.25 ml/minute (95% confidence level). At steady state the mean portal pressure was 16.25±1.45 mmHg with a mean volume of 854±313.75 ml/minute (95% confidence level). Bile production was observed during the perfusion period. Hemodynamic parameters were similar to the physiological parameters observed in normothermic perfusion model of the porcine liver. CONCLUSION: A normothermic oxygenated ex-vivo perfusion circuit was successfully constructed using the sheep liver. A sustainable functional circuit with physiological hemodynamic parameters was achieved. Further study on sheep model seems to be feasible.

Elizabethkingia Meningoseptica in a Case of Biliary Tract Infection Following Liver Transplantation.

BACKGROUND Elizabethkingia meningoseptica (E. meningoseptica) is an aerobic Gram-negative bacillus known to thrive in moist environments, and is now recognized as a hospital-acquired infection, being found to contaminate hospital equipment, respiratory apparatus, hospital solutions, water, and drainage systems. Nosocomial infection with E. meningoseptica occurs in immunocompromised patients, requires specialized identification methods, and is resistant to conventional antibiotics. We report a case of E. meningoseptica infection arising from a percutaneous transhepatic biliary drainage (PTBD) tube. CASE REPORT A 55-year-old Saudi woman underwent liver transplantation. The post-operative period immediately following transplantation was complicated by anastomotic biliary stricture and bile leak, which was managed with percutaneous transhepatic cholangiography (PTC) with PTBD. She developed right upper quadrant abdominal pain, and her ultrasound (US) showed a subdiaphragmatic collection. Microbial culture from the PTBD tube was positive for E. meningoseptica, which was treated with intravenous ciprofloxacin and metronidazole. This case is the second identified infection with E. meningoseptica at our specialist center, fifteen years after isolating the first case in a hemodialysis patient. We believe that this is the first case of E. meningoseptica infection to be reported in a liver transplant patient. CONCLUSIONS The emerging nosocomial infectious organism, E. meningoseptica is being seen more often on hospital equipment and medical devices and in water. This case report highlights the need for awareness of this infection in hospitalized immunocompromised patients and the appropriate identification and management of infection with E. meningoseptica.

Appendicitis in northern aboriginal children: does delay in definitive treatment affect outcome?

BACKGROUND: The treatment of northern aboriginal children (NAC) is often complicated by distance from a treating facility. We sought to compare outcomes of NAC requiring transfer with appendicitis to those who presented locally. We hypothesized that NAC with appendicitis experienced higher rates of perforation and increased length of stay (LOS). METHODS: A retrospective chart review of 210 appendectomies was performed. Charts were reviewed for age, sex, weight, days of symptoms before presentation, time of transfer, leukocyte count (white blood cell count), usage of antibiotics prior to transfer, time to operation, type of procedure and findings, pathology, postoperative outcomes, and LOS. RESULTS: Sixty-eight children were NAC, whereas 142 were local. The average transfer times for NAC was 10 hours (range, 4-20 hours). The two groups had similar ages (11.1 vs 10.7 years), time to presentation (1.64 vs 1.85 days), and LOS (2.91 vs 2.90 days). Significantly higher perforation rates (44 vs 28%; P = .02), higher white blood cell count (17.9 vs 16.0; P = .02), and longer times to operation after arrival (10.3 vs 7.0 hours; P = .0002) were noted in NAC. Postoperative complications were similar between groups. Forty-seven (69%) NAC received antibiotics prior to transfer, which did not affect rate of rupture. CONCLUSION: NAC with appendicitis experience longer transfer times and higher perforation rates than local children without a difference in length of stay or complications. Pretransfer antibiotics do not reduce perforation rates but may impact complications. We endorse their use if a delay in transfer is anticipated.

The effect of in vitro tracheal occlusion on branching morphogenesis in fetal lung explants from the rat nitrofen model of congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Fetal tracheal occlusion (TO) has been investigated as a treatment option for lung hypoplasia secondary to congenital diaphragmatic hernia. Tracheal occlusion has been shown to accelerate lung growth, but its effect on bronchial branching is unknown. In this study, we characterize the effects of in vitro TO on bronchial branch development in fetal lung explants derived from the nitrofen rat model of congenital diaphragmatic hernia. METHODS: Rat dams were gavaged nitrofen on gestational day 9.5, and fetal lungs were harvested for explant culture on gestational day 14 (term, 22 days). Four experimental groups were investigated, with TO performed ex vivo using cautery: control, control + TO, nitrofen, and nitrofen + TO. Explants were incubated for 72 hours. Representative photographs were taken at 0, 24, 48, and 72 hours from the time of culture, and the number of distal branches was counted for each explant. The Student t test was used to compare distal branch measurements. RESULTS: A minimum of 12 fetal lung explants were cultured for each group. By 24 hours, all explants undergoing TO had more branch iterations than explants that did not. Moreover, TO in nitrofen-exposed explants increased bronchial branching to control levels by 24 hours in culture. CONCLUSION: Our results suggest that TO at day 14 increases branching in normal and nitrofen-exposed lung explants. In addition, TO increases airway branching in nitrofen-exposed explants to control levels suggesting that early TO reverses the lung hypoplasia seen in this model.