Protection of colorectal anastomosis with an intraluminal bypass device for patients undergoing an elective anterior resection: a pilot study.

BACKGROUND: Currently, the only clinically valid method to prevent morbidity and mortality related to colorectal anastomotic leaks is by construction of a protective ileostomy. Intraluminal bypass might also be a possible way to proctect the anastomosis. The aim of the present study was to evaluate the CG-100 intraluminal bypass device for the reduction of anastomosis-related morbidity and stoma creation in cases of rectal resection. METHODS: A prospective study was conducted on patients having sphincter-preserving rectal resection who were treated with the CG-100 device at Soroka University Medical Center, Beer Sheva, Israel between May 2015 and February 2017. The device was implanted during surgery and removed after 10 ± 1 days. All patients underwent a radiologic leak test with water-soluble contrast prior to removal of the device. Patients were followed for 30 days. Information about adverse events, anastomotic leaks, device usability and tolerance were collected. RESULTS: Forty-seven patients participated in the study. Most patients were operated on due to cancer 44 (93.6%). Four (9%) patients received a primary protective stoma on top of the CG-100 device as part of the learning curve of the surgical team and none required a stoma after device removal. Five (9%) serious adverse events were reported, but only 2 (4%) were classified as related to the device. One was a transient enterocutaneous fistula after removal of the device. The second was an asymptomatic radiologic leak in 1 (2.1%) patient which was treated by keeping the device in place and antibiotic treatment for another 10 days without creation of diverting ileostomy. CONCLUSIONS: CG-100 may provide a safe method for fecal diversion over a newly created anastomosis without the complications related to stoma creation and closure. A larger prospective randomized study in patients originally scheduled to receive diverting stoma is needed to confirm these findings.

Risk of adhesive obstruction after colorectal surgery: the benefits of the minimally invasive approach may extend well beyond the perioperative period.

BACKGROUND: Risk of adhesive small-bowel obstruction (SBO) is high following open colorectal surgery. Laparoscopic surgery may induce fewer adhesions; however, the translation of this advantage to a reduced rate of bowel obstruction has not been well demonstrated. This study evaluates whether SBO is lower after laparoscopic compared with open colorectal surgery. METHODS: Patients who underwent laparoscopic abdominal colorectal surgery, without any previous history of open surgery, from 1998 to 2010 were identified from a prospective laparoscopic database. Details regarding occurrence of symptoms of SBO (colicky abdominal pain; nausea and/or vomiting; constipation; abdominal distension not due to infection or gastroenteritis), admissions to hospital with radiological findings confirming SBO, and surgery for obstruction after the laparoscopic colectomy were obtained by contacting patients and mailed questionnaires. Patients undergoing open colorectal surgery for similar operations during the same period and without a history of previous open surgery also were contacted and compared with the laparoscopic group for risk of obstruction. RESULTS: Information pertaining to SBO was available for 205 patients who underwent an elective laparoscopic procedure and 205 similar open operations. The two groups had similar age, gender, and sufficiently long duration of follow-up. Despite a significantly longer duration of follow-up for the laparoscopic group, admission to hospital for SBO was similar between groups. Patients who underwent laparoscopic surgery also had significantly lower operative intervention for SBO (8% vs. 2%, p = 0.006). CONCLUSIONS: Although the rate of SBO was similar after laparoscopic and open colorectal surgery, the need for operative intervention for SBO was significantly lower after laparoscopic operations. These findings especially in the context of the longer follow-up for laparoscopic patients suggests that the lower incidence of adhesions expected after laparoscopic surgery likely translates into long-term benefits in terms of reduced SBO.

Colectomy with ileorectal anastomosis has a worse 30-day outcome when performed for colonic inertia than for a neoplastic indication.

AIM: Whether bowel related dysfunction adversely affects postoperative recovery after total colectomy with ileorectal anastomosis (C + IRA) for colonic inertia (CI) has not been previously well evaluated. This study compared the early postoperative outcome of C + IRA for CI and for other noninflammatory indications. METHOD: Patients undergoing elective C + IRA from 1999 to 2010 were identified from a prospectively maintained database. Since inflammation in the rectum or small bowel may influence the outcome, patients with inflammatory bowel disease were excluded. Patients undergoing surgery for CI (group A) were compared with patients having the operation for other benign noninflammatory diseases (group B). Demographics, American Society of Anesthesiologists (ASA) score, body mass index (BMI), surgical procedure and 30-day complications were assessed. RESULTS: The study population consisted of 333 patients undergoing elective C + IRA (99 men, mean age 39 ± 16 years). The procedure was laparoscopic in 163 (49%) patients. Groups A (n = 131) and B (n = 202) had similar age and ASA score (39 ± 11 vs 39 ± 19 years, P = 0.4; 2.2 ± 0.5 vs 2.4 ± 0.7). Group A patients had lower BMI (25 ± 5 vs 28 ± 8 kg/m(2) , P = 0.002), more women (99 vs 51%, P < 0.001) and fewer laparoscopic procedures (43 vs 53%, P = 0.04). Compared with group B, group A had a greater incidence of postoperative ileus (32 vs 19%, P = 0.009), higher overall morbidity (36 vs 15%, P < 0.001) and increased length of stay (8.4 ± 6 vs 7.2 ± 5 days, P < 0.006). These differences persisted when subgroups of patients who underwent laparoscopic or open surgery were compared. CONCLUSION: Although CI is considered a 'benign' condition, patients undergoing C + IRA for this indication have significant morbidity compared with patients having the operation for other noninflammatory benign conditions.

Case-matched comparison of perioperative outcomes after surgical treatment of sigmoid diverticulitis in solid organ transplant recipients versus immunocompetent patients.

AIM: To compare the perioperative outcomes following surgery for sigmoid diverticulitis in transplant recipients and immunocompetent patients. METHOD: Solid organ transplant recipients operated on for sigmoid diverticulitis from 1995 to 2010 were case-matched to immunocompetent patients based on surgical procedure, American Society of Anesthesiologists classification, Hinchey score, elective vs urgent surgery, age ± 10 years and year of surgery ± 5 years. Demographics, clinical presentation and perioperative outcomes were assessed. RESULTS: Of 5329 consecutive patients undergoing heart, lung, kidney and liver transplantation since 1995, 51 (0.6%) underwent surgery for diverticulitis between 1995 and 2010 with 14% mortality and 45% morbidity. Urgent surgery in 37/51 patients [Hartmann's procedure 28, sigmoidectomy with diverting ileostomy 8, loop ileostomy 1 (9 cases within 2 months after transplantation)] was associated with significantly increased postoperative mortality (19%vs 0%, P = 0.01), increased morbidity (51%vs 24%, P = 0.03) and longer mean hospital stay (19 vs 13 days, P = 0.1) when compared with immunocompetent patients. Four patients undergoing urgent surgery had suffered previous episodes of diverticulitis treated nonoperatively. Elective surgery was associated with no mortality in 14 transplant recipients (nine sigmoidectomy with diverting ileostomy, five sigmoidectomy without diversion) or in immunocompetent controls. Following elective procedures, transplant recipients had similar morbidity and increased hospital stay (29% and 9.6 vs 6.5 days, P = 0.2, respectively). Permanent stoma rates and postoperative morbidity after stoma takedown were comparable in the two groups. All living patients except one (kidney) retained their graft function. CONCLUSIONS: Urgent surgery for sigmoid diverticulitis in transplant recipients is associated with worse postoperative outcomes when compared with immunocompetent patients, unlike elective surgery. Future studies will need to clarify the role of early surgery after the first diverticulitis episode.

Evidence-based recommendations for the therapeutic management of angioedema owing to hereditary C1 inhibitor deficiency: consensus report of an International Working Group.

Angioedema owing to hereditary deficiency of C1 inhibitor (HAE) is a rare, life-threatening, disabling disease. In the last 2 years, the results of well-designed and controlled trials with existing and new therapies for this condition have been published, and new treatments reached the market. Current guidelines for the treatment for HAE were released before the new trials and before the new treatments became available and were essentially based on observational studies and expert opinion. To provide evidence-based HAE treatment guidelines supported by the new studies, a conference was held in Gargnano del Garda, Italy, from September 26 to 29, 2010. The meeting hosted 58 experienced HAE expert physicians, representatives of pharmaceutical companies and representatives of HAE patients' associations. Here, we report the topics discussed during the meeting and evidence-based consensus about management approaches for HAE in adult/adolescent patients.

The hypereosinophilic syndrome associated with CD4+CD3- helper type 2 (Th2) lymphocytes.

We describe herein the clinical and laboratory manifestations of a unique group of patients (pts) presenting with hypereosinophilic syndrome (HES) who were treated in our medical centers for 4-13 years. Skin biopsies, flow cytometry of peripheral blood mononuclear cells (PBMC), assays for cytokines and immunoglobulin (Ig) production in vitro, and Southern blots of T-cell receptor (TCR) genes were performed. All four pts had a persistent hypereosinophilia (> 1.9 x 10(9)/L) and chronic skin rash. Three of four had elevated IgE, thrombotic manifestations and lung involvement (asthma and/or infiltrates), and one had deforming sero-negative arthritis of the hands. 66-95% of their peripheral T-cells expressed CD4 but not CD3 or TCR molecules on the cell surface membrane. Activated CD4+CD3- cells secreted interleukin (IL)-4 and/or 5, and were required for maximal IgE secretion by autologous B-cells. Two pts had evidence of rearrangement of TCR genes of the CD4+CD3- cells, one of whom died of anaplastic lymphoma. In conclusion, HES with CD4+CD3- lymphocytosis may be associated with high serum IgE, dermatological, pulmonary, thrombotic and rheumatic manifestations which may be due to Th2 effects of CD4+CD3- cells migrating to end organs. Fatal systemic lymphoid malignancy may also develop in some pts with monoclonal expansion of the CD4+CD3- T-cells.

The adenosine-induced mechanism for the acquisition of ischemic tolerance in primary rat neuronal cultures.

Neurons can be preconditioned by various procedures to resist ischemic insult. The preconditioning mechanism induced by adenosine ("the adenosine mechanism") was characterized in primary rat neuronal cultures, employing a model of chemical ischemia. The protective mechanism, initiated by activation of adenosine receptors, consists of a signal transduction pathway, involving activation of protein kinase C (PKC) and opening of ATP-sensitive potassium (K(ATP)) channels. Direct activation (and inhibition) of PKC, as well as opening of K(ATP) channels, also confers protection. The opening of the K(ATP) channels mediates the signal activated by the adenosine receptors, and probably also that activated by PKC. The acquired ischemic resistance lasts up to 5 days, depending on the activating substance. The adenosine-activated cascade of events leading to ischemic tolerance in neurons is similar to that operating in cardiomyocytes.

Ischemic tolerance conferred to cultured rat neurons by heat shock is not mediated by opening of adenosine triphosphate-sensitive potassium channels.

The effect of sublethal heat shock on the capacity of neurons to resist subsequent ischemia-reperfusion-induced cell injury, was studied in a model of primary rat neuronal cultures, subjected to chemical ischemia. Exposure of the cultures to sublethal heat shock (42 degrees C; 20 min) resulted in elevation in cellular content of heat shock protein (HSP)-70, at 4 h following the shock, and in acquisition of a 15 h 'time window of protection' against ischemia-reperfusion insult, with maximum protection at 4 h. Presence in the culture medium of glibenclamide (2 microM), a blocker of ATP sensitive potassium (K(ATP)) channels, did not abolish the acquisition of protection throughout the entire duration of the acquired 'time window of protection'. The results demonstrate that heat shock induces in neurons a protective mechanism against ischemia-reperfusion insult, probably associated with enhanced expression of HSPs, which does not depend on opening of K(ATP) channels. In this respect, the neuronal 'heat-shock mechanism' for the acquisition of ischemic tolerance differs from the neuronal 'adenosine mechanism' and probably also from the heart 'heat shock mechanism' for the acquisition of protection.

Opening of K(ATP) channels is mandatory for acquisition of ischemic tolerance by adenosine.

Binding of adenosine to neuronal adenosine receptors activates a signal transduction pathway (the adenosine mechanism), leading to a temporary ischemic tolerance. We have demonstrated before that induction of this mechanism in primary rat neuronal cultures, by activation of adenosine receptors, or by activation of protein kinase C (PKC), confers a wide time window of ischemic tolerance, lasting up to 72h, the early (immediate) part of which depends on opening of K(ATP) channels (glibenclamide sensitive). Here we demonstrate that the entire duration of the ischemic tolerance conferred by activation of the adenosine mechanism depends on opening of the K(ATP) channels. Thus, opening of the K(ATP) channels appears to be a mandatory step in the adenosine mechanism, leading to the creation of the wide time window of ischemic tolerance.

A cholesterol-lowering gene maps to chromosome 13q.

A cholesterol-lowering gene has been postulated from familial hypercholesterolemia (FH) families having heterozygous persons with normal LDL levels and homozygous individuals with LDL levels similar to those in persons with heterozygous FH. We studied such a family with FH that also had members without FH and with lower-than-normal LDL levels. We performed linkage analyses and identified a locus at 13q, defined by markers D13S156 and D13S158. FASTLINK and GENEHUNTER yielded LOD scores >5 and >4, respectively, whereas an affected-sib-pair analysis gave a peak multipoint LOD score of 4.8, corresponding to a P value of 1.26x10-6. A multipoint quantitative-trait-locus (QTL) linkage analysis with maximum-likelihood binomial QTL verified this locus as a QTL for LDL levels. To test the relevance of this QTL in an independent normal population, we studied MZ and DZ twin subjects. An MZ-DZ comparison confirmed genetic variance with regard to lipid concentrations. We then performed an identity-by-descent linkage analysis on the DZ twins, with markers at the 13q locus. We found strong evidence for linkage at this locus with LDL (P<.0002), HDL (P<.004), total cholesterol (P<.0002), and body-mass index (P<.0001). These data provide support for the existence of a new gene influencing lipid concentrations in humans.

Chorionic villus sampling prior to pregnancy termination, a tool for forensic paternity testing.

Chorionic villus sampling (CVS), prior to pregnancy termination (pre-termination CVS), is suggested as a tool for forensic paternity testing. Unlike the abortion material, which consists of ruptured tissues of fetal and maternal origin, extra-embryonic membranes obtained through CVS can provide an uncontaminated source of fetal tissue for genotyping. We discuss the possibility of confined placental mosaicism (CPM) and its implications on the polymerase chain reaction (PCR) based analyses of short tandem repeats (STRs) and the D1S80 loci.

Impact of different low-density lipoprotein (LDL) receptor mutations on the ability of LDL to support lymphocyte proliferation.

Based on the demand for cholesterol for membrane formation, we determined the ability of low-density lipoprotein (LDL) to support proliferation in lymphocytes bearing different LDL receptor mutations, which were treated "in vitro" with lovastatin to inhibit endogenous cholesterol synthesis. Peripheral lymphocytes were isolated from two patients with homozygous familial hypercholesterolemia (FH), one homozygote for the mutation N804K (FH(Colmenar)) in exon 17, herein described for the first time, and a compound heterozygote carrying the mutations D280G and G528V, which determine a transport-defective biochemical phenotype. Flow cytometric analysis with 1,1'-dioctadecyl-3,3,3,3'-tetramethylindocarbocyanineperchlorate (Dil)-LDL showed normal LDL binding but defective internalization in lymphocytes from case 1, whereas in lymphocytes from case 2 both LDL binding and internalization were affected. Studies with mitogen-stimulated lymphocytes demonstrated that despite the different phenotype, the ability of LDL to support proliferation was impaired in both cases to a similar extent. These results indicate that internalization of the LDL particle is required for expression of the mitogenic effect of LDL.

Opening of ATP-sensitive potassium channels by cromakalim confers tolerance against chemical ischemia in rat neuronal cultures.

The effect of opening and of blocking of ATP-sensitive potassium (K(ATP)) channels on the short-term capacity of neurons to resist ischemia-reperfusion-induced cell injury, was studied in a model of primary rat neuronal cultures, subjected to metabolic poisoning by iodoacetic acid (150 microM, 150 min), followed by reperfusion (1 h). The metabolic poisoning resulted in a marked decrease in cellular ATP content (from 65.3 +/- 13.4 to 21.6 +/- 11.7 nmole/mg protein), simulating an ischemia, or hypoxia-induced condition of energy crisis. The degree of neuronal damage was assessed by the trypan blue exclusion test. Exposure of the neurons to the channel-opener cromakalim (10 microM; 15 min), prior to the insult, induced resistance, which could be abolished by the specific channel blocker glibenclamide (2 microM). Glibenclamide also abolished the protection acquired by preconditioning of the neurons with iodoacetate (IA; 100 microM), the adenosine A1 agonist N6-(R)-phenylisopropyladenosine (R-PIA; 100 microM), or with the protein kinase C (PKC) activator 1,2 dioctanoyl-rac-glycerol (DOG; 1 microM). The results indicate that in the neurons, opening of the K(ATP) channels confers protection against an ATP-depleting crisis, and suggest that the protective effects induced by adenosine and by activation of PKC, are mediated by the opening of these channels.

Markedly reduced bile acid synthesis but maintained levels of cholesterol and vitamin D metabolites in mice with disrupted sterol 27-hydroxylase gene.

Sterol 27-hydroxylase is important for the degradation of the steroid side chain in conversion of cholesterol into bile acids and has been ascribed a regulatory role in cholesterol homeostasis. Its deficiency causes the autosomal recessive disease cerebrotendinous xanthomatosis (CTX), characterized by progressive dementia, xanthomatosis, and accelerated atherosclerosis. Mice with a disrupted cyp27 (cyp27(-/-)) had normal plasma levels of cholesterol, retinol, tocopherol, and 1,25-dihydroxyvitamin D. Excretion of fecal bile acids was decreased (<20% of normal), and formation of bile acids from tritium-labeled 7alpha-hydroxycholesterol was less than 15% of normal. Compensatory up-regulation of hepatic cholesterol 7alpha-hydroxylase and hydroxymethylglutaryl-CoA reductase (9- and 2-3-fold increases in mRNA levels, respectively) was found. No CTX-related pathological abnormalities were observed. In CTX, there is an increased formation of 25-hydroxylated bile alcohols and cholestanol. In bile and feces of the cyp27(-/-) mice only traces of bile alcohols were found, and there was no cholestanol accumulation. It is evident that sterol 27-hydroxylase is more important for bile acid synthesis in mice than in humans. The results do not support the contention that 27-hydroxylated steroids are critical for maintenance of cholesterol homeostasis or levels of vitamin D metabolites in the circulation.

Elimination of cholesterol in macrophages and endothelial cells by the sterol 27-hydroxylase mechanism. Comparison with high density lipoprotein-mediated reverse cholesterol transport.

Cultured macrophages and endothelial cells have been reported to secrete 27-oxygenated metabolites of cholesterol. This mechanism was compared with the classical high density lipoprotein (HDL)-dependent reverse cholesterol transport. Under standard conditions, macrophage preparations had considerably higher capacity to secrete 27-hydroxycholesterol and 3beta-hydroxy-5-cholestenoic acid than had endothelial cells and fibroblasts. Western blotting showed that lung macrophages contained the most sterol 27-hydroxylase protein of the cells tested. The relative amounts of 3beta-hydroxy-5-cholestenoic acid produced by the macrophages were also highest. Macrophages derived from monocytes of patients with sterol 27-hydroxylase deficiency did not secrete 27-oxygenated products, demonstrating that sterol 27-hydroxylase is the critical enzyme for the conversion of cholesterol into the 27-oxygenated steroids. That sterol 27-hydroxylase is responsible not only for 27-hydroxylation of cholesterol but also for the further oxidation of this steroid into 3beta-hydroxy-5-cholestenoic acid was shown with use of tritium-labeled 27-hydroxycholesterol and an inhibitor of sterol 27-hydroxylase. Secretion of 27-oxygenated products by the cultured macrophages as well as the ratio between the alcohol and the acid appeared to be dependent upon total 27-hydroxylase activity, the availability of substrate cholesterol, and the presence of an acceptor for 27-hydroxycholesterol in the medium. With albumin as extracellular acceptor, the major secreted product was 3beta-hydroxy-5-cholestenoic acid. Under such conditions, secretion of labeled 27-oxygenated products was higher than that of labeled cholesterol from lung alveolar macrophages preloaded with [4-14C]cholesterol. With HDL as acceptor, 27-hydroxycholesterol was the major secreted product, and the total secretion of labeled 27-oxygenated products was only about 10% of that of labeled cholesterol. Thus, 27-hydroxycholesterol and cholesterol may compete for HDL-mediated efflux from the cells. The results support the contention that the sterol 27-hydroxylase-mediated elimination of cholesterol is more important in macrophages than in endothelial cells. This mechanism may be an alternative and/or a complement to the classical HDL-mediated reverse cholesterol transport in macrophages, in particular when the concentration of HDL is low.

Identification of two novel LDL receptor gene defects in French-Canadian pediatric population: mutational analysis and biochemical studies.

Familial hypercholesterolemia (FH) is at least twofold more prevalent in French Canadians from Québec than in most Western populations. Although our recent data confirmed this high frequency of heterozygous FH in our pediatric population with hypercholesterolemia, none of the five established molecular defects for the French-Canadian population was detected in 29% of the unrelated French-Canadian children characterized by a persistent increase in LDL (low density lipoprotein receptor) cholesterol and a positive parental history of hyperlipidemia (Assouline et al., 1995). To probe for new mutations, six of these molecularly undiagnosed children were investigated as index patients. By using single-strand conformation polymorphism analysis and DNA sequencing, two novel mutations were identified in two of these subjects: (1) 7-base pair (bp) duplication following nucleotide 681 (according to the cDNA sequence) in exon 4 (681ins7), which causes a frameshift, the introduction of a stop at codon 208, and premature chain termination, and (2) A to G change in exon 8 substituting a tyrosine for a cysteine at amino acid 354 (Y354C). A third subject carried the recently reported exon 10 mutation (Y468X), whereas the remaining three patients demonstrated various known polymorphisms with no effect on gene product. Rapid molecular assays were developed to detect the two new mutations as well as the Y468X mutation. Screening of our cohort showed heterozygosity in 1/88, in 2/88, and in 2/88 of patients for the 681ins7, the Y354C, and the Y468X mutations, respectively.