Ahmed Eid

Effectiveness of Acute Normovolemic Hemodilution to Minimize Allogeneic Blood Transfusion in Major Liver Resections

Background Liver resection is a major operation for which, even with the improvements in surgical and anesthetic techniques, the reported rate of blood transfusion was rarely less than 30%. About 60% of transfused patients require only 1 or 2 units of blood, a blood requirement that may be accommodated by the use of acute normovolemic hemodilution (ANH). Methods The efficacy, hemodynamic effects, and safety of ANH were investigated in a randomized, active-control study in patients with American Society of Anesthesiologists status I–II who were undergoing major liver resection with fentanyl–nitrous oxide–isoflurane anesthesia. Patients were randomized to the ANH (n = 39) or control group (n = 39). Patients in the ANH group underwent hemodilution to a target hematocrit of 24%. The indication for blood transfusion was standardized. In both groups transfusion was started at a hematocrit of 20%. The primary efficacy endpoint was the avoidance of allogeneic blood transfusion in the intraoperative period and first 72 h after surgery. Various laboratory and hemodynamic parameters as well as postoperative morbidity were monitored to define the safety of ANH in this patient population. Results During the perioperative period, 14 control patients (36%) received at least one unit of allogeneic blood compared with 4 patients (10%) in the ANH group (P < 0.05). The hemodilution process was not associated with significant changes in patients’ hemodynamics. Morbidity was similar between the control and the ANH groups. Postoperative hematocrit levels and biochemical liver, renal, and standard coagulation test results were similar in both groups. Conclusions Acute normovolemic hemodilution in patients with American Society of Anesthesiologists status I–II undergoing major liver resection may allow a significant number of patients to avoid exposure to allogeneic blood.

Activation of hepatic stellate cells after phagocytosis of lymphocytes: A novel pathway of fibrogenesis.

Increased CD8‐T lymphocytes and reduced natural killer (NK) cells contribute to hepatic fibrosis. We have characterized pathways regulating the interactions of human hepatic stellate cells (HSCs) with specific lymphocyte subsets in vivo and in vitro. Fluorescence‐activated cell sorting (FACS) was used to characterize human peripheral blood lymphocytes (PBLs) and intrahepatic lymphocytes (IHLs) obtained from healthy controls and from patients with either hepatitis B virus (HBV) or hepatitis C virus (HCV) with advanced fibrosis. Liver sections were analyzed by immunohistochemistry and confocal microscopy. To investigate in vitro interactions, PBLs from healthy controls or patients with HCV cirrhosis were co‐cultured with an immortalized human HSC line (LX2 cells) or with primary HSCs. Significant alterations in lymphocyte distribution were identified in IHLs but not PBLs. The hepatic CD4/CD8 ratio and NK cells were significantly reduced in HBV/HCV patients. Expression of alpha‐smooth muscle actin and infiltration of CD4, CD8, and NK cells were readily apparent in liver sections from patients with cirrhosis but not in healthy controls. Lymphocytes from each subset were in proximity to HSCs primarily within the periportal regions, and some were directly attached or engulfed. In culture, HSC activation was stimulated by HCV‐derived CD8‐subsets but attenuated by NK cells. Confocal microscopy identified lymphocyte phagocytosis within HSCs that was completely prevented by blocking intracellular adhesion molecule 1 (ICAM‐1) and integrin molecules, or by irradiation of HSCs. LX2 knockdown of either Cdc42 or Rac1 [members of the Rho‐guanosine triphosphatase (GTPase) family] prevented both phagocytosis and the activation of HSC by HCV‐derived lymphocytes. Conclusion: The CD4/CD8 ratio and NK cells are significantly decreased in livers with advanced human fibrosis. Moreover, disease‐associated but not healthy lymphocytes are engulfed by cultured HSCs, which is mediated by the Rac1 and Cdc42 pathways. Ingestion of lymphocytes by HSCs in hepatic fibrosis is a novel and potentially important pathway regulating the impact of lymphocytes on the course of hepatic fibrosis. (HEPATOLOGY 2008.)

Involvement of the CXCL12/CXCR4 pathway in the advanced liver disease that is associated with hepatitis C virus or hepatitis B virus

Chronic hepatitis C virus (HCV) and hepatitis B virus (HBV) infection is accompanied by inflammation and fibrosis eventually leading to cirrhosis. The chemokine CXCL12 is involved in chronic inflammatory conditions. The role of the CXCL12/CXCR4 pathway in HCV‐ and HBV‐associated liver inflammation and fibrosis was therefore studied. The levels and tissue localization of CXCL12 in liver and plasma of HCV and HBV patients were tested using immunohistochemistry and ELISA. The expression and function of CXCR4 on liver‐infiltrating lymphocytes (LIL) were tested by FACS and transwell migration assays. We found that CXCL12 is expressed by bile duct epithelial cells in normal liver tissue. Bile duct proliferation and liver fibrosis in chronic HCV and HBV infection result in the anatomical re‐distribution of CXCL12 in the liver. Moreover, CXCL12 is up‐regulated in the endothelium of neo‐blood‐vessels formed in active inflammatory foci and is significantly elevated, compared with controls, in the plasma of patients with advanced liver fibrosis. Complementing these observations were others indicating that over 50% of LIL express CXCR4 and, in response to CXCL12, migrated and adhered to fibronectin. These observations suggest an important role for the CXCL12/CXCR4 pathway in recruitment and retention of immune cells in the liver during chronic HCV and HBV infection.

Development of a MicroRNA-Based Molecular Assay for the Detection of Papillary Thyroid Carcinoma in Aspiration Biopsy Samples

BACKGROUND Although thyroid nodules are common and diagnosed in over 5% of the adult population, only 5% harbor malignancy. Patients with clinically suspicious thyroid nodules need to undergo fine-needle aspiration biopsy (FNAB). The main limitation of FNAB remains indeterminate cytopathology. Only 20%-30% of the indeterminate nodules harbor malignancy, and therefore up to 80% of patients undergo unnecessary thyroidectomy. The aim of this study was to identify and validate a panel of microRNAs (miRNAs) that could serve as a platform for an FNAB-based diagnostic for thyroid neoplasms. METHODS The study population included 27 consecutive patients undergoing total thyroidectomy for FNAB-based papillary thyroid cancer (n = 20) and benign disorders (n = 7). Aspiration biopsy was performed from the index lesion and from the opposite lobe normal tissue in all study patients at the time of operation. RNA was extracted from all aspiration biopsy samples. Quantitative polymerase chain reaction on a panel of previously selected miRNAs was performed. Polymerase chain reaction results were compared with final histopathology. miRNA from tumor tissues was amplified using the highest value of each miRNA expression in normal tissue as a threshold for malignancy detection. RESULTS Diagnostic characteristics were most favorable for mir-221 in differentiating benign from malignant thyroid pathology. mir-221 was overexpressed in 19 patients (p < 0.0001) with a sensitive yield of 95%. Specificity, negative and positive predictive value, and accuracy of the miRNA panel were 100%, 96%, 100%, and 98%, respectively. CONCLUSIONS miRNA quantification for differential diagnosis of thyroid neoplasms within aspiration biopsy samples is feasible and may improve the accuracy of FNAB cytology.

Epidural Anesthesia and Analgesia in Liver Resection

IMPLICATIONS In patients undergoing major liver resection, the decision to introduce an epidural catheter and the timing of its removal should be made with care because of the prolonged changes in platelet count and in prothrombin time that develop in some patients.

Pancreaticojejunostomy versus controlled pancreaticocutaneous fistula in pancreaticoduodenectomy for perianipullary carcinoma

BACKGROUND Anastomotic leak of the pancreaticojejunostomy is a major cause of morbidity and mortality following pancreaticoduodenectomy. Reports have described a large variety of techniques for performing this anastomosis and managing the pancreatic stump. In an attempt to obviate the pancreaticojejunostomy, we prospectively studied the technique of ligating the pancreatic duct and using external drains to create a temporary controlled pancreaticocutaneous fistula. PATIENTS AND METHODS Thirty-five consecutive patients who were to undergo pancreaticoduodenectomy for periampullary carcinoma were prospectively randomized to one of two groups: pancreaticojejunostomy (PJ) (n = 18) or controlled pancreaticocutaneous fistula (CPF) (n = 17). The groups were well matched for age, sex, coexisting medical illnesses, type of tumor, and preoperative condition. Except for the management of the pancreatic remnant, all patients in both groups underwent an identical procedure. Major morbidity, length of hospitalization, duration of the controlled pancreatic fistula, and mortality were analyzed over a mean follow-up interval of 26 months (range 5 months to 7.5 years). RESULTS The CPF group experienced lower overall operative morbidity rates than the PJ group (24% versus 56%, P < 0.01). Two patients (11%) in the PJ group and none in the CPF group died (P = NS). Half the morbidity in the PJ group and both mortalities were related to anastomotic leak. The CPF and PJ groups left the hospital after mean stays of 26.4 and 42.2 days respectively (< 0.01). CONCLUSIONS Compared to pancreaticojejunal anastomosis, creation of a temporary controlled pancreaticocutaneous fistula in patients who undergo pancreaticoduodenectomy for periampullary malignancy has no appreciable risk. It is associated with reduced morbidity and shorter length of hospitalization.

Analysis of differentially expressed genes in hepatocellular carcinoma using cDNA arrays

Hepatocellular carcinoma (HCC) is characterized by multiple somatic mutations, including DNA rearrangements, that affect many cell‐growth regulatory pathways. Many genes differentially expressed in HCC have been reported previously, but the patterns of expression varied significantly between patients who bore different risk factors for HCC. To identify genes whose differential expression could serve as a “signature” for diagnosis and prognosis of HCC, we performed analyses of differentially expressed genes in three cases of HCC with different risk factors using the Atlas Human Cancer cDNA Expression Arrays. Among all 597 genes present on the array, only three were found to be coordinately differentially expressed in all three HCC cases, in agreement with published data. These three genes, Cu/Zn superoxide dismutase, osteonectin/secreted protein acidic and rich in cysteine, and matrix metalloproteinase 14, could serve as candidates for the HCC “signature.” Ten genes were found to be coordinately differentially expressed in only two of three tested HCC cases. On the other hand, many genes that had been reported previously as differentially expressed in HCC failed to show the described pattern of expression in this group. The results of this study confirm the great variability in gene‐expression patterns in HCC and establish the utility of the array technology for identifying both the HCC signature genes and individual gene‐expression patterns for purposes of patient‐oriented therapy.

Multifocality in well-differentiated thyroid carcinomas calls for total thyroidectomy.

BACKGROUND Multifocality is an important factor when recommending surgery for papillary thyroid cancer (PTC). The aim of this study is to assess the incidence and characterize the spread pattern of multifocal PTC (mPTC) in patients undergoing total thyroidectomy. METHODS All thyroidectomies performed between 2003 and 2008 were reviewed identifying 289 patients. Data were obtained for demographics, clinical data, and histopathological findings. RESULTS Of the patients with papillary carcinoma, mPTC was identified in 150 patients (57%), of which 71% had lesions in the contralateral lobe. There were no significant differences in multifocality rate for gender, pathology type, and all tumor size subgroups including ≤1 cm. Pathology examination of representative sections versus the entire gland examination resulted in a significantly lower incidence of contralateral disease (P = .04). CONCLUSIONS Multifocal and contralateral lesions are common in PTC and their incidence is not related to tumor size. Pathology entire gland examination is strongly recommended to properly assess the rate of mPTC.

Successful renal transplantation from two donors with methanol intoxication

Two patients with acute methanol intoxication are reported, one with acute renal failure. Both were declared brain-dead and kidneys were harvested at 80 and 130 hr after hospital admission. All four kidneys were transplanted and subsequently functioned well. In both donors who had received ethanol treatment, thrombocytopenia was present. The reluctance to use kidneys from such donors and from donors with acute renal failure before harvesting is discussed. Waiting lists for renal transplantation are growing and there is a world-wide shortage of cadaver organs. We were recently surprised to find reluctance to consider two local patients dying from methanol intoxication as suitable organ donors, and we report the outcome of four kidneys transplanted from these donors. We were unable to find any similar cases reported in the English literature.

Is presensitization relevant to liver transplantation outcome

The impact of anti-HLA antibodies and crossmatch (CM) on liver transplantation (LT) outcome is still controversial. In this retrospective study we analyzed LT outcome according to pretransplant pre-formed anti-HLA antibodies and CM status. Serum anti-HLA antibodies were screened by ELISA assay, utilizing One Lambda antigen tray-mixed (LAT-M). CMs were performed by the complement dependent cytotoxicity test using Dithiotreitol treated sera. Anti-HLA antibodies were studied in 80 recipients; 56/80 had positive LAT-M tests (PLAT-M), whereas the remaining 24 recipients tested negative for both classes I and II (NLAT-M). Rejection episodes were more frequent in PLAT-M compared with NLAT-M group in post-LT intervals of <1 week (p = 0.05), 1 week-3 months (p = 0.035), and 3-12 months (p = 0.076). Graft and patient survival rates were better, albeit not significantly, in the NLAT-M compared with PLAT-M recipients. CM status was investigated in 62/80 recipients, 18/62 recipients had positive CM (PCM), and 44 had negative CM (NCM). Five of 18 PCM recipients (28%) experienced early graft loss compared with 1/44 (2%) with NCM (p = 0.006). Rejection episodes were more frequent within first 3 months post-LT in PCM recipients compared with NCM (p = 0.015). One-year graft survival rate was better in NCM, compared with PCM recipients (graft loss of 2/44 vs 5/18). NCM PLAT-M had a higher incidence of rejection episodes compared with the NCM NLAT-M group (p = 0.031). The presence of anti-HLA antibodies suggests a deleterious effect on LT outcome, and was associated with an increased incidence of early graft loss and rejection episodes.