M1 Macrophages Activate Notch Signalling in Epithelial Cells: Relevance in Crohn's Disease.

BACKGROUND: The Notch signalling pathway plays an essential role in mucosal regeneration, which constitutes a key goal of Crohn's disease (CD) treatment. Macrophages coordinate tissue repair and several phenotypes have been reported which differ in the expression of surface proteins, cytokines and hypoxia-inducible factors (HIFs). We analysed the role of HIFs in the expression of Notch ligands in macrophages and the relevance of this pathway in mucosal regeneration. METHODS: Human monocytes and U937-derived macrophages were polarized towards the M1 and M2 phenotypes and the expression levels of HIF-1α, HIF-2α, Jagged 1 (Jag1) and delta-like 4 (Dll4) were evaluated. The effects of macrophages on the expression of hairy and enhancer of split-1 (HES1, the main target of Notch signalling) and intestinal alkaline phosphatase (IAP, enterocyte marker) in epithelial cells in co-culture were also analysed. Phenotype macrophage markers and Notch signalling were evaluated in the mucosa of CD patients. RESULTS: M1 macrophages were associated with HIF-1-dependent induction of Jag1 and Dll4, which increased HES1 protein levels and IAP activity in co-cultured epithelial cells. In the mucosa of CD patients a high percentage of M1 macrophages expressed both HIF-1α and Jag1 while M2 macrophages mainly expressed HIF-2α and we detected a good correlation between the ratio of M1/M2 macrophages and both HES1 and IAP protein levels. CONCLUSION: M1, but not M2, macrophages are associated with HIF-1-dependent induction of Notch ligands and activation of epithelial Notch signalling pathway. In the mucosa of chronic CD patients, the prevalence of M2 macrophages is associated with diminution of Notch signalling and impaired enterocyte differentiation.

Hypoxic macrophages impair autophagy in epithelial cells through Wnt1: relevance in IBD.

A defective induction of epithelial autophagy may have a role in the pathogenesis of inflammatory bowel diseases. This process is regulated mainly by extracellular factors such as nutrients and growth factors and is highly induced by diverse situations of stress. We hypothesized that epithelial autophagy is regulated by the immune response that in turn is modulated by local hypoxia and inflammatory signals present in the inflamed mucosa. Our results reveal that HIF-1α and Wnt1 were co-localized with CD68 in cells of the mucosa of IBD patients. We have observed increased protein levels of ß-catenin, phosphorylated mTOR, and p62 and decreased expression of LC3II in colonic epithelial crypts from damaged mucosa in which ß-catenin positively correlated with phosphorylated mTOR and negatively correlated with autophagic protein markers. In cultured macrophages, HIF-1 mediated the increase in Wnt1 expression induced by hypoxia, which enhanced protein levels of ß-catenin, activated mTOR, and decreased autophagy in epithelial cells in co-culture. Our results demonstrate a HIF-1-dependent induction of Wnt1 in hypoxic macrophages that undermines autophagy in epithelial cells and suggest a role for Wnt signaling and mTOR pathways in the impaired epithelial autophagy observed in the mucosa of IBD patients.

Fistulectomy and sphincteric reconstruction for complex cryptoglandular fistulas.

OBJECTIVE: Complex anal fistulas (CFs) are difficult to treat. Endoanal advancement flap (EAF) is one of the standard treatment options for such clinical conditions. Immediate sphincter repair after fistulectomy (ISR) is not commonly performed because of the fear of causing postoperative incontinence. The objective of this study was to compare the results of both techniques. METHOD: We retrospectively analysed a prospectively entered database composed of 146 patients (112 M; 34 F), undergoing operations for CF of cryptoglandular origin. The patients were divided in two groups: Group A: (EAF); n = 71 patients; Group B: (ISR); n = 75 patients. RESULTS: Forty-two fistulas (28.7%) were recurrent, 98 trans-sphincteric (TS) and 37 suprasphincteric (SS). Twenty-six (17.7%) patients had some degree of preoperative continence disturbances, 11 in Group A vs 15 in Group B (P = 0.47). After a mean follow up of 13 months (12-60), fistula persisted or recurred in 13 (18.3%) patients in Group A vs eight (10.6%) in Group B (P = 0.19) irrespective of the fistula type (TS or SS). Thirty-one (43.6%) patients in Group A vs 16 (21.3%) in Group B presented postoperative continence disturbances (P < 0.001). No changes were observed with the Faecal Incontinence Quality of Life Scale (FIQLS). Group A patients had a significant reduction of maximal rest pressure after surgery. After ISR, no significant changes in pressures were observed. CONCLUSION: Immediate sphincter repair can be a therapeutic option in selected cases of CF, mainly when associated with incontinence or increased risk factors.

Quality of mesorectum after laparoscopic resection for rectal cancer - results of an audited teaching programme in Spain.

OBJECTIVE: The aim of this prospective observational study was to compare the quality of total mesorectal excision between laparoscopic and open surgery for rectal cancer. METHOD: In April 2006, the Spanish Association of Surgeons started an audited teaching programme. The project was similar to the Norwegian one and several training courses were arranged. Patients were classified into two groups: laparoscopic rectal resection (LR) and open rectal resection (OR). The quality of the mesorectum was scored: complete, nearly complete or incomplete. The circumferential margin (CRM) was considered positive, if tumour was located 1 mm or less from the surface of the specimen. RESULTS: Between 2006 and 2008, 604 patients underwent rectal resection with total mesorectal excision for rectal cancer: 209 patients were included in the LR group and 395 patients in the OR group. There were no differences in terms of number of lymph nodes affected, distance of the tumour from CRM. The mesorectum was complete in 464 (76.8%), nearly complete in 91 (15.1%) and incomplete in 49 patients (8.1%). CRM was negative in 534 patients (88.4%). No differences were observed between the two groups. The overall postoperative morbidity rate was 38.8% in LR group and 44.6% in OR group (P = 0.170). Overall postoperative mortality rate was 2.5%. One patient died (0.5%) in the LR group and 14 patients died (3.5%) in the OR group (P = 0.021). CONCLUSION: Laparoscopic resection for rectal cancer is feasible with the quality of mesorectal excision and postoperative outcomes similar to those of open surgery.

Prospective study of artificial anal sphincter and dynamic graciloplasty for severe anal incontinence.

BACKGROUND AND AIMS: Dynamic graciloplasty and artificial anal sphincter are two options for refractory incontinence, the efficacy of which was compared in a prospective study. PATIENTS AND METHODS: Between November 1966 and June 1998, 16 patients were operated on (artificial anal sphincter 8, dynamic graciloplasty 8). Four consecutive operations with each technique were performed by two colorectal surgeons (one initiated the study with the neosphincter and the other with dynamic graciloplasty). Two independent observers assessed postoperative results at 4-month intervals. Patients were followed up to January 2001, with a median (interquartile range) of 44 (13) months and 39 (15) months for the nesophincter and the dynamic graciloplasty, respectively. RESULTS: Fourteen patients had complications. In the immediate postoperative period; there were eight cases of wound healing-related problems (four in the graciloplasty group). Perineal infection occurred in one patient in the graciloplasty group. At follow-up there were 11 complications (6 in the neosphincter group). Four patients undergoing neosphincter implantation had erosion or pain at the cuff site and had the implant removed (a new device was reimplanted in one). Four patients undergoing dynamic graciloplasty had the stimulator removed. Postoperatively the neosphincter was associated with a significantly lower score on the continence grading scale of the Cleveland Clinic Florida than graciloplasty. CONCLUSION: The artificial anal sphincter is a more convenient technique than dynamic graciloplasty for institutions treating small number of patients. However, technical failures and complications during follow-up that require reoperation are very high in both types of treatments.

Use of photoplethysmography to determine gastrointestinal perfusion pressure: an experimental canine model.

OBJECTIVES: To develop an experimental model to assess the parietal perfusion pressure (PPP) of the digestive tract using photoplethysmography. MATERIALS AND METHODS: Twenty-two mongrel dogs were used. Progressive external compression was applied to the intestinal wall and the PPP was assessed with photoplethysmography. The study group was divided into two groups. In group 1 PPP was measured at the levels of the stomach, duodenum, jejunum and transverse colon. In group 2 PPP was measured after temporary occlusion of the truncal and marginal circulation of the jejunum to provide further variables. RESULTS: The PPP decreased significantly for each successive distal section. Correlation coefficients and indices for PPP and mean arterial pressures were statistically significant (p < 0.005). Truncal occlusion provoked a drop in PPP whereas marginal occlusion scarcely modified the basal results. CONCLUSIONS: Photoplethysmography, through measurements of the residual arterial wave amplitude, is a valid method of determining quantitatively the PPP of the digestive tract and could be useful in a clinical environment.

Complications and functional outcome following artificial anal sphincter implantation.

BACKGROUND: The postoperative complications and functional outcome following 24 consecutive implantations of an artificial anal sphincter were assessed prospectively. METHODS: A total of 24 artificial anal sphincters (Acticon Neosphincter) were implanted in 22 patients (mean age 47 years). The mean follow-up period was 28 (range 6-48) months. Results were assessed prospectively by two independent observers at 4-month intervals. The cumulative probability of artificial anal sphincter removal was analysed by the Kaplan-Meier method. RESULTS: Five patients were free of complications. During the postoperative period, complications occurred in nine patients, two of whom required reoperation. During follow-up, complications developed in ten patients, nine of whom were reoperated. Definitive device explantation was necessary in seven patients. The cumulative probability of device explantation was 44 per cent at 48 months. The 15 patients with functioning implants were followed up for a mean of 26 (range 7-48) months. Continence grading improved from a mean of 18 (range 14-20) in the preoperative period to 4 (range 0-14) after operation (P < 0.001). Resting anal canal pressure in patients with a functioning implant increased from a mean of 35 (range 8-87) mmHg before operation to 54 (range 34-70) mmHg after implantation (P < 0.01). CONCLUSION: An artificial anal sphincter is a useful alternative for refractory faecal incontinence but the incidence of late postoperative complications is high.

Utilidad de la ecografía anorrectal en la enfermedad de Crohn perianal / Utility of anorectal echography in perianal Crohn's disease

Introducción. La ecografía anorrectal (EAR) es una exploración sencilla, cuyo valor en el diagnóstico de la patología anorrectal está altamente contrastado en la bibliografía. El propósito de este estudio ha sido examinar la utilidad de la EAR en pacientes con enfermedad de Crohn (EC) intestinal que presentan algún tipo de manifestación perianal de su enfermedad. Material y métodos. Entre octubre de 1996 y febrero de 1999 se han realizado un total de 18 EAR en 16 pacientes diagnosticados de EC intestinal y con sospecha clínica de presentar algún proceso anorrectal. Utilizamos un ecógrafo B&K Medical con un transductor rotatorio de 360°. El motivo más frecuente de petición de EAR fue la valoración de proctalgia de etiología incierta (5 casos, 28 por ciento). Otros motivos fueron: fístulas anales (4 casos, 22 por ciento), sospecha de absceso anal (3 casos, 17 por ciento), control evolutivo (3 casos, 17 por ciento), incontinencia fecal (2 casos, 11 por ciento) y sepsis perianal (un caso, 6 por ciento). Resultados. La orientación diagnóstica del clínico coincidió con los hallazgos ecográficos en 12 casos (67 por ciento). Una imagen compatible con absceso fue reconocida en 10 casos (55 por ciento), dos de ellos ya sospechados clínicamente y los otros ocho fueron hallazgos asociados fundamentalmente a fístulas y proctalgias de etiología no filiada. Se detectaron defectos esfinterianos en los 2 casos de incontinencia fecal y en otros 2 pacientes fue un hallazgo casual. En el caso de las fístulas anorrectales la EAR permitió conocer de modo más preciso la relación de las mismas con los esfínteres. Conclusiones. La EAR es de gran utilidad en la EC perianal ya que es capaz de detectar con precisión los defectos esfinterianos y los abscesos anales, motivo por el que resulta de gran valor en el caso de proctalgias o abscesos no sospechados clínicamente. Creemos que la EAR debe ser realizada después del examen rectal, la rectoscopia o la colonoscopia en estos enfermos (AU)

Estudio cooperativo nacional sobre la utilización de aspiración nasogástrica y alimentación precoz en cirugía colorrectal / Nationwide cooperative study on the utilization of nasogastric aspiration and early feeding in colorectal surgery

Introducción. El objetivo de este estudio fue evaluar la seguridad y eficacia de la sonda nasogástrica y la alimentación oral precoz en cirugía colorrectal. Pacientes y métodos. Hemos realizado un estudio multicéntrico, prospectivo y no aleatorizado que incluía a pacientes sometidos a cirugía colorrectal electiva. Los grupos de estudio fueron: grupo 1: sonda nasogástrica postoperatoria; grupo 2: sin sonda nasogástrica y dieta oral progresiva habitual, y grupo 3: sin sonda nasogástrica y alimentación oral precoz. Las variables analizadas fueron: presencia de náuseas y vómitos, necesidad de colocación de la sonda nasogástrica, tolerancia a la dieta oral, día de comienzo de peristalsis audible, inicio de tránsito para gases y heces, uso de fármacos antieméticos, grado subjetivo de bienestar postoperatorio y aparición de complicaciones. Resultados. Al final del estudio se recibieron 406 encuestas. La distribución ha sido: grupo 1: 200 pacientes (49,3 por ciento), grupo 2: 152 pacientes (37,4 por ciento) y grupo 3: 54 pacientes (13,3 por ciento). La aparición de peristaltismo audible, el inicio de tránsito a gases y heces, así como la tolerancia a la alimentación oral, fueron más precoces en los grupos 2 y 3 (sin sonda nasogástrica) que en el grupo 1, con diferencias estadísticamente significativas (p < 0,05). El grado de comodidad postoperatoria fue mayor en los grupos sin sonda nasogástrica. Las complicaciones aparecieron de forma similar en todos los grupos. Conclusiones. La alimentación oral precoz y la restricción del uso de sonda nasogástrica en cirugía colorrectal electiva son seguras y sin desventajas en relación con el uso sistemático de SNG y dieta oral progresiva (AU)

Anorectal function in patients with complete rectal prolapse. Differences between continent and incontinent individuals.

AIMS: A study is made of the alterations in anorectal physiology among rectal prolapse patients, evaluating the differences between fecal continent and incontinent individuals. PATIENTS AND METHODS: Eighteen patients with complete rectal prolapse were divided into two groups: Group A (8 continent individuals) and Group B (10 incontinent women), while 22 healthy women were used as controls (Group C). Clinical exploration and perineal level measurements were performed, along with anorectal manometry, electrophysiology, and anorectal sensitivity to electrical stimuli. RESULTS: The main antecedents of the continent subjects were excess straining efforts, while the incontinent women presented excess straining and complex deliveries. Pathological perineal descent was a frequent finding in both groups, with a hypotonic anal canal at rest (p < 0.001 vs controls) and at voluntary squeezing (p < 0.001 vs controls). In turn, the incontinent patients exhibited a significantly lower anal canal pressure at rest than the continent women (p < 0.05). There were no significant differences between Groups A and C in terms of pudendal motor latency, though latency was significantly longer in Group B than in the controls (p < 0.01). Moreover, pudendal neuropathy was more common, severe and often bilateral in Group B. There were no differences in rectal sensation to distention or in terms of the volumes required to relax the internal anal sphincter. In turn, both prolapse groups exhibited diminished anal canal and rectal sensitivity to electrical stimuli. CONCLUSIONS: Patients with rectal prolapse exhibit a hypotonic anal canal at rest, regardless of whether they are continent to feces or not. Continent patients have less pudendal neuropathy and therefore less pressure alterations at voluntary sphincter squeeze than incontinent individuals.

Can digital examination substitute anorectal manometry for the evaluation of anal canal pressures?

INTRODUCTION: Anorectal manometry provides objective information on the sphincter function of the anal canal. However, in many centers sphincter function is evaluated by digital examination, due to the unavailability of manometry. OBJECTIVE: A study is made to correlate the sensitivity and specificity of a quantitative digital examination in the analysis of sphincter tone with the pressures recorded by manometry, and to examine the capacity of both techniques to discriminate continent subjects and incontinent patients. PATIENTS AND METHODS: A total of 191 patients were divided into three groups: control (C), obstructive defecation (OD) and fecal incontinence (FI). Subjective quantitative digital evaluation of anal tone was performed on a scale of 0 to 5 points at rest, and 0 to 10 points at squeeze. A correlation analysis was performed, and the sensitivity and specificity of each fecal incontinence diagnostic test was determined. RESULTS: Digital examination found rectal tone to be diminished in elderly patients. A significant correlation was established between the digital and manometric tone readings, both at rest and at squeeze. Both techniques showed a low anal sphincter pressure in the FI group versus the C and OD groups. Differences in tone were recorded between the C and OD groups with manometry, but not with digital examination. The latter was in turn found to be more sensitive but less specific than manometry in differentiating between fecal continence and incontinence. CONCLUSIONS: Although digital examination does not substitute anorectal manometry, a good correlation exists between the two techniques. In this sense, digital examination may afford an approximate clinical evaluation of some fecal continence mechanisms in those centers where manometry is not available.

Intraoperative photoplethysmographic diagnosis of ischemic colitis.

Intraoperative evaluation of ischemic colitis presents several problems related to diagnosis, severity, and extension. The aim of this study was to determine the usefulness of photopletysmography (PPG) to detect colonic arterial wave amplitude changes in patients operated on for ischemic colitis, comparing the affected area with a control area on the transverse colon. Four patients were studied, two with gangrenous colitis, and two with protracted "transient" ischemic colitis. All four patients survived. PPG is a useful method for intraoperative diagnosis and surgical assessment of ischemic colitis.

Evolutive study of the functional results after restorative proctocolectomy for ulcerative colitis.

AIM: Evolutive study of the functional results after restorative proctocolectomy for ulcerative colitis. PATIENTS AND METHODS: Prospective study in 24 patients with an ileoanal "J" pouch (n = 8: mucosectomy and hand-sewn anastomosis; n = 16: stapled anastomosis without mucosectomy). A clinical survey was carried out during two evolutive follow-ups of the functional pouch (medians: 14.5 and 39.0 months) as well as an anorectal manometry study during the preoperative period and in two follow-ups after the creation of the pouch (medians: 6.0 and 35.5 months). RESULTS: The mean frequency of defecation per 24 hours and per night was significantly reduced in the first follow-up (5.5 [24 h]; p < 0.003 and 1.0 [per night]; p < 0.009) compared with the postoperative period (7.9 [24 h] and 1.4 [per night]), with no significant changes in the second follow-up (5.5 [24 h] and 0.9 [per night]). At the same time, it has been significantly lower in patients with stapled anastomosis in the different evolutive follow-ups. One patient (4.2%) had major fecal incontinence in the two evolutive follow-ups and 7 (29.2%) and 6 (25%) patients had minor incontinence in the first and second follow-up respectively. The mean maximum resting anal pressure in the first follow-up was significantly lower (p = 0.002) in patients with mucosectomy than the values observed in patients with stapled anastomosis (35.4 vs 68.0 mmHg). In the second follow-up increased significantly (p = 0.046) only in patients with mucosectomy (55.1 mmHg). Recto-anal inhibitory reflex was present in 2 (10%) and 9 (45%) patients in the first and second follow-up respectively. CONCLUSIONS: The functional results improve significantly with the follow-up time, fundamentally during the first year of the functional pouch.

Prevalence of pudendal neuropathy in fecal incontinence. Results of a prospective study.

PURPOSE: A prospective study was made of the prevalence and associations of pudendal neuropathy in 96 patients with fecal incontinence (72 females and 24 males). METHODS: Clinical exploration, perineal level measurement, anorectal manometry, and electrophysiologic evaluations (pudendal nerve terminal motor latency (PNTML) and external sphincter fiber density (FD)) were performed. RESULTS: Pudendal neuropathy (defined as PNTML > 2.2 ms or FD > 1.65) was found in 67 patients (69.8 percent) and was more common in females (75 percent) than in males (50 percent; P = 0.05). Pudendal neuropathy was also more frequent in patients with pathologic perineal descent (85 percent vs. 55 percent; P < 0.01) or exhibiting risk factors such as difficult labor or excessive defecatory straining (P < 0.01). Perineal level at staining correlated inversely with both PNTML and FD (P < 0.01). Manometric findings suggested greater external anal sphincter damage in patients with pudendal neuropathy than in those suffering fecal incontinence but no neuropathy (P < 0.05). Pressure caused by the striated anal sphincter was also inversely correlated to PNTML. Pudendal neuropathy was encountered in 37 of 33 (58.7 percent) patients with sphincter injury vs. in 31 of 33 (93.9 percent) patients with idiopathic fecal incontinence (P < 0.01). CONCLUSIONS: Pudendal neuropathy is an etiologic or associated factor often present in patients with fecal incontinence. In this sense, clinical, perineometric, and manometric findings correlate with pudendal neuropathy, though such explorations do not suffice to detect it.

Evaluation of residual vascularisation in oesophageal substitution gastroplasty by surface oximetry-capnography and photoplethysmography. An experimental study.

OBJECTIVE: To evaluate residual vascularisation in gastroplasty and its possible relation to the development of anastomotic fistulas or dehiscences after oesophageal resection. DESIGN: Experimental open study. MATERIAL: Eleven mongrel dogs. INTERVENTIONS: Gastric parietal blood flow was evaluated by photoplethysmography and measurement of surface oxygen and carbon dioxide tensions under basal conditions and after Akiyama's tubular gastroplasty. Temperature, heart rate, and electrocardiogram; arterial pressure, pulmonary arterial pressure, pulmonary capillary pressure, central venous pressure, cardiac output, venous oxygen saturation, and arterial blood gas tensions were monitored under stable haemodynamic conditions. RESULTS: After gastroplasty, the mean serosal oxygen tension (pO2) of 8.6 mmHg and carbon dioxide tension (pCO2) of 99.5 mmHg and residual photoplethysmographic wave amplitude (8%) indicated considerable severe ischaemia at the fundus. There was relative ischaemia of the mid-stomach with residual mean values of 52.7 mmHg, 77.8 mmHg, and 57% for pO2; pCO2 and PPG wave amplitude, respectively. CONCLUSIONS: Important devascularisation of the fundus, theoretically incompatible with healing, occurs after gastroplasty. Operative photoplethysmography and surface measurements of pO2 and pCO2 are good ways of evaluating the level and degree of ischaemia in gastric tubes for oesophageal replacement.

The use of photoplethysmography and Doppler ultrasound to predict anastomotic viability after segmental intestinal ischaemia in dogs.

OBJECTIVE: To compare photoplethysmography and Doppler ultrasonography in the prediction of the viability of experimental jejunoileal anastomoses in the presence of arterial (n = 11), venous (n = 11), and mixed arterial and venous (n = 9) segmental ischaemia. DESIGN: Experimental open study. MATERIAL: 31 Mongrel dogs. INTERVENTIONS: Laparotomy, selective devascularisation, and anastomosis. In 20 of the experiments a bolus injection of papaverine was given into the superior mesenteric artery. Second laparotomy on day 15, or earlier if indicated. OUTCOME MEASURES: Correlation between photoplethysmography, Doppler ultrasonography, and macroscopic and histological findings. RESULTS: All non-viable anastomoses had photoplethysmographic wave amplitudes of less than 10% of the control value, with sensitivity and specificity of 100%. Venous volume and maximum venous outflow had a sensitivity of 72% and a specificity of 77%. Doppler ultrasonography had a sensitivity of 100%, but a specificity of only 67%. Papaverine had no effect on photoplethysmographic wave amplitude in these experiments. CONCLUSION: Photoplethysmography is the preferred method of assessing intestinal viability in the presence of ischaemia.