Subtotal colectomy and ileorectal anastomosis for slow transit constipation: clinical follow-up at median of 15 years.

BACKGROUND: Slow transit constipation is characterised by prolonged colonic transit and reliance on laxatives. The pathophysiology is poorly understood and in its most severe form, total colectomy with ileorectal anastomosis is the final treatment option. We present a follow-up study of the long-term function in patients who had surgery for laxative-resistant slow transit constipation. METHODS: A postal survey was sent to assess bowel frequency, abdominal pain, St Mark's continence score, satisfaction with procedure, likelihood to choose the procedure again, and long-term rates of small bowel obstruction and ileostomy. Longitudinal data from a subgroup studied 23 years previously are reported. RESULTS: Forty-two patients (male = 2) were available for follow-up out of an initial cohort of 102. Mean time since surgery was 15.9 years (range 1.7-29.7) years. Fifty percent had < 4 bowel motions per day, most commonly Bristol stool 6, mean St Mark's score 7.45. Twenty-one percent had severe incontinence. Satisfaction and likelihood to choose surgery were high (median 10/10). There was a high rate of small bowel obstruction, suggesting pan-intestinal dysmotility in some cases. Conversion to ileostomy occurred in 8 patients. In the longitudinal follow-up in 15 subjects, continence deteriorated (p < 0.01), stool consistency softened (p < 0.01), and stool frequency fell (p < 0.01). CONCLUSIONS: Satisfactory stool frequency was achieved in the long term, and although 21% had incontinence scores > 12, patient satisfaction was high. This is the longest reported follow-up of colectomy for slow transit constipation, with longitudinal outcomes reported. There was considerable attrition of patients, so larger, longitudinal studies are required to better ascertain the functional outcomes of these patients.

Colonic motor abnormalities in slow transit constipation defined by high resolution, fibre-optic manometry.

BACKGROUND: Slow transit constipation (STC) is associated with colonic motor abnormalities. The underlying cause(s) of the abnormalities remain poorly defined. In health, utilizing high resolution fiber-optic manometry, we have described a distal colonic propagating motor pattern with a slow wave frequency of 2-6 cycles per minute (cpm). A high calorie meal caused a rapid and significant increase in this activity, suggesting the intrinsic slow wave activity could be mediated by extrinsic neural input. Utilizing the same protocol our aim was to characterize colonic meal response STC patients. METHODS: A fiber-optic manometry catheter (72 sensors at 1 cm intervals) was colonoscopically placed with the tip clipped at the ascending or transverse colon, in 14 patients with scintigraphically confirmed STC. Manometric recordings were taken, for 2 h pre and post a 700 kCal meal. Data were compared to 12 healthy adults. KEY RESULTS: Prior to and/or after the meal the cyclic propagating motor pattern was identified in 13 of 14 patients. However, the meal, did not increase the cyclic motor pattern (preprandial 7.4 ± 7.6 vs postprandial 8.3 ± 4.5 per/2 h), this is in contrast to the dramatic increase observed in health (8.3 ± 13.3 vs 59.1 ± 89.0 per/2 h; p < 0.001). CONCLUSIONS & INFERENCES: In patients with STC a meal fails to induce the normal increase in the distal colonic cyclic propagating motor patterns. We propose that these data may indicate that the normal extrinsic parasympathetic inputs to the colon are attenuated in these patients.

Quantification of in vivo colonic motor patterns in healthy humans before and after a meal revealed by high-resolution fiber-optic manometry.

BACKGROUND: Until recently, investigations of the normal patterns of motility of the healthy human colon have been limited by the resolution of in vivo recording techniques. METHODS: We have used a new, high-resolution fiber-optic manometry system (72 sensors at 1-cm intervals) to record motor activity from colon in 10 healthy human subjects. KEY RESULTS: In the fasted colon, on the basis of rate and extent of propagation, four types of propagating motor pattern could be identified: (i) cyclic motor patterns (at 2-6/min); (ii) short single motor patterns; (iii) long single motor patterns; and (iv) occasional retrograde, slow motor patterns. For the most part, the cyclic and short single motor patterns propagated in a retrograde direction. Following a 700 kCal meal, a fifth motor pattern appeared; high-amplitude propagating sequences (HAPS) and there was large increase in retrograde cyclic motor patterns (5.6 ± 5.4/2 h vs 34.7 + 19.8/2 h; p < 0.001). The duration and amplitude of individual pressure events were significantly correlated. Discriminant and multivariate analysis of duration, gradient, and amplitude of the pressure events that made up propagating motor patterns distinguished clearly two types of pressure events: those belonging to HAPS and those belonging to all other propagating motor patterns. CONCLUSIONS & INFERENCES: This work provides the first comprehensive description of colonic motor patterns recorded by high-resolution manometry and demonstrates an abundance of retrograde propagating motor patterns. The propagating motor patterns appear to be generated by two independent sources, potentially indicating their neurogenic or myogenic origin.

Low-resolution colonic manometry leads to a gross misinterpretation of the frequency and polarity of propagating sequences: Initial results from fiber-optic high-resolution manometry studies.

BACKGROUND: High-resolution manometry catheters are now being used to record colonic motility. The aim of this study was to determine the influence of pressure sensor spacing on our ability to identify colonic propagating sequences (PS). METHODS: Fiber-optic catheters containing 72-90 sensors spaced at 1 cm intervals were placed colonoscopically to the cecum in 11 patients with proven slow transit constipation, 11 patients with neurogenic fecal incontinence and nine healthy subjects. A 2 h section of trace from each subject was analyzed. Using the 1 cm spaced data as the gold standard, each data set was then sub-sampled, by dropping channels from the data set to simulate sensor spacing of 10, 7, 5, 3, and 2 cm. In blinded fashion, antegrade and retrograde PS were quantified at each test sensor spacing. The data were compared to the PSs identified in the corresponding gold standard data set. KEY RESULTS: In all subject groups as sensor spacing increased; (i) the frequency of identified antegrade and retrograde PSs decreased (P < 0.0001); (ii) the ratio of antegrade to retrograde PSs increased (P < 0.0001); and (iii) the number of incorrectly labeled PSs increased (P < 0.003). CONCLUSIONS & INFERENCES: Doubling the sensor spacing from 1 to 2 cm nearly halves the number of PSs detected. Tripling the sensor spacing from 1 to 3 cm resulted in a 30% chance of incorrectly labeling PSs. Closely spaced pressure recording sites (<2 cm) are mandatory to avoid gross misrepresentation of the frequency, morphology, and directionality of colonic propagating sequences.

Expression and localization of pannexin-1 hemichannels in human colon in health and disease.

BACKGROUND: Pannexin-1 (Panx1) proteins can function as channels for adenosine triphosphate (ATP) release, but there have been limited studies investigating their potential role in the human intestine. The aim of this study was to characterize Panx1 expression and distribution in the human colon and its potential involvement in inflammatory bowel diseases (IBD). METHODS: Human colon segments were dissected into mucosa and muscularis layers, and evaluated for Panx1 expression by real-time PCR and Western blotting. Immunohistochemistry was conducted to localize the cellular distribution of Panx1 in intact tissues. KEY RESULTS: In the colonic muscularis of ulcerative colitis (UC), Panx1 mRNA expression showed a 3.5-fold reduction compared with control (P = 0.0015), but no change was seen in UC mucosa. In contrast, down-regulation of Panx1 mRNA was observed in both muscularis and mucosa of Crohn's disease (CD), showing a 2.7- and 1.8-fold reduction, respectively (P < 0.05). There was reduced Panx1 protein expression in CD muscularis, but no change in CD mucosa, UC muscularis, or UC mucosa. Pannexin-1 immunoreactivity was mainly localized to enteric ganglia, blood vessel endothelium, erythrocytes, epithelial cells, and goblet cells. Inflammatory bowel disease samples showed a similar overall pattern of Panx1 staining, but in UC myenteric ganglia, there was a significant reduction in Panx1 immunoreactivity. Significant Panx1 positive leukocyte infiltrations were seen at the sites of inflammation. CONCLUSIONS & INFERENCES: The presence of Panx1 in the colon and changes to its distribution in disease suggests that Panx1 channels may play an important role in mediating gut function and in IBD pathophysiology.

The effect of sacral nerve stimulation on distal colonic motility in patients with faecal incontinence.

BACKGROUND: Sacral nerve stimulation (SNS) is an effective treatment for neurogenic faecal incontinence (FI). However, the clinical improvement that patients experience cannot be explained adequately by changes in anorectal function. The aim of this study was to examine the effect of SNS on colonic propagating sequences (PSs) in patients with FI in whom urgency and incontinence was the predominant symptom. METHODS: In patients with FI a high-resolution fibre-optic manometry catheter, containing 90 sensors spaced at 1-cm intervals, was positioned colonoscopically and clipped to the caecum. A unipolar or quadripolar tined electrode was implanted into the S3 sacral nerve foramen. Colonic manometry was evaluated in a double-blind randomized crossover trial, using true suprasensory stimulation or sham stimulation. Each stimulation period, lasting 2 h, was preceded by a 2-h basal manometric recording. RESULTS: All 11 patients studied showed a colonic response to SNS. In ten patients there was a significant increase in the frequency of retrograde PSs throughout the colon during true stimulation compared with sham stimulation (P = 0·014). In one outlier, with baseline retrograde PS frequency nine times that of the nearest patient, a reduction in retrograde PS frequency was recorded. Compared with sham stimulation, SNS had no effect on the frequency of antegrade PSs or high-amplitude PSs. CONCLUSION: SNS modulates colonic motility in patients with faecal urge incontinence. These data suggest that SNS may improve continence and urgency through alteration of colonic motility, particularly by increasing retrograde PSs in the left colon.

Pancolonic motor response to subsensory and suprasensory sacral nerve stimulation in patients with slow-transit constipation.

BACKGROUND: Sacral nerve stimulation (SNS) is emerging as a potential treatment for patients with constipation. Although SNS can elicit an increase in colonic propagating sequences (PSs), the optimal stimulus parameters for this response remain unknown. This study evaluated the colonic motor response to subsensory and suprasensory SNS in patients with slow-transit constipation. METHODS: Patients with confirmed slow-transit constipation were studied. Either a water-perfused manometry catheter or a high-resolution fibre-optic manometry catheter was positioned colonoscopically to the caecum. A temporary electrode was implanted transcutaneously in the S3 sacral nerve foramen. In the fasted state, three conditions were evaluated in a double-blind randomized fashion: sham, subsensory and suprasensory stimulation. Each 2-h treatment period was preceded by a 2-h basal period. The delta (Δ) value was calculated as the frequency of the event during stimulation minus that during the basal period. RESULTS: Nine patients had readings taken with a water-perfused catheter and six with a fibre-optic catheter. Compared with sham stimulation, suprasensory stimulation caused a significant increase in the frequency of PSs (mean(s.d.) Δ value - 1·1(7·2) versus 6·1(4·0) PSs per 2 h; P = 0·004). No motor response was recorded in response to subsensory stimulation compared with sham stimulation. Compared with subsensory stimulation, stimulation at suprasensory levels caused a significant increase in the frequency of PSs (P = 0·006). CONCLUSION: In patients with slow-transit constipation, suprasensory SNS increased the frequency of colonic PSs, whereas subsensory SNS stimulation did not. This has implications for the design of therapeutic trials and the clinical application of the device.

Pancolonic spatiotemporal mapping reveals regional deficiencies in, and disorganization of colonic propagating pressure waves in severe constipation.

BACKGROUND: The morphology, motor responses and spatiotemporal organization among colonic propagating sequences (PS) have never been defined throughout the entire colon of patients with slow transit constipation (STC). Utilizing the technique of spatiotemporal mapping, we aimed to demonstrate 'manometric signatures' that may serve as biomarkers of the disorder. METHODS: In 14 female patients with scintigraphically confirmed STC, and eight healthy female controls, a silicone catheter with 16 recording sites spanning the colon at 7.5 cm intervals was positioned colonoscopically with the tip clipped to the cecum. Intraluminal pressures were recorded for 24 h. KEY RESULTS: Pan-colonic, 24 h, spatiotemporal mapping identified for the first time in STC patients: a marked paucity of propagating pressure waves in the midcolon (P = 0.01), as a consequence of a significant (P < 0.0001) decrease in extent of propagation of PS originating in the proximal colon; an increase in frequency of retrograde PS in the proximal colon; a significant reduction in the spatiotemporal organization among PS (P < 0.001); absence of the normal nocturnal suppression of PS. CONCLUSIONS & INFERENCES: Pancolonic, 24 h, spatiotemporal pressure mapping readily identifies characteristic disorganization among consecutive PS, regions of diminished activity and absent or deficient fundamental motor patterns and responses to physiological stimuli. These features are all likely to be important in the pathophysiology of slow transit constipation.

Postanal repair--do the long-term results justify the procedure?

OBJECTIVE: Early outcomes after postanal repair (PAR) demonstrated excellent results but subsequent reports showed an ever declining success rate in maintaining continence. The aim of this study was to document long-term continence after PAR and relate this to patient satisfaction and quality of life. METHOD: Patients with neurogenic incontinence who underwent PAR from 1986 to 2002 were interviewed by telephone, utilizing a questionnaire which assessed continence, patient satisfaction, overall improvement, and quality of life. RESULTS: One-hundred one patients from four surgeons were identified. Fifty-four patients were excluded because of loss to follow-up. Three had a stoma (two for incontinence), four had undergone a graciloplasty, leaving 57 patients (F = 53), mean duration of follow-up of 9.1 years (2.2-18.7 years). Mean CCS was 11.7 (SD 7.4). 26% (n = 15) scored none to minimal incontinence (CCS 0-5), 26% moderate (CCS 6-12), and 48% (n = 27) severe incontinence (CCS 13-24). 79% (n = 45) were satisfied with the outcome. A low CCS significantly correlated with good patient satisfaction, and was influenced by high QOL score (P < 0.0001). A high CCS significantly correlated with high bowel frequency (P = 0.0007). A favourable CCS was associated with a good QOL, a shorter duration of follow-up, and being able to distinguish flatus and stool. CONCLUSIONS: In patients with neurogenic faecal incontinence selected following anorectal physiology studies, PAR remains a useful treatment. It is associated with low morbidity and results in a satisfactory long-term subjective outcome, despite the fact that many patients have a high incontinence score.

Rectogesic (glyceryl trinitrate 0.2%) ointment relieves symptoms of haemorrhoids associated with high resting anal canal pressures.

OBJECTIVE: Some haemorrhoids are associated with high resting anal canal pressures. The aim of this study was to assess if Rectogesic, a topical glyceryl trinitrate 0.2% ointment was effective in relieving symptoms of early grade haemorrhoids associated with high resting anal canal pressures. METHOD: This was a prospective, two-centre, open label study of 58 patients with persistent haemorrhoidal symptoms. Patients with first or second degree haemorrhoids and a maximum resting anal canal pressure > 70 mmHg were included. Rectogesic was applied three times a day for 14 days. Anorectal manometry was performed 30 min after the first application of Rectogesic. A 28-day diary was completed during 14 days of therapy and for 14 days after cessation of treatment. This recorded the incidence of rectal bleeding, and visual analogue scales for anal pain, throbbing, pruritus, irritation and difficulty in bowel movement. RESULTS: Maximum resting anal canal pressures were reduced after application of Rectogesic (115.0 +/- 40.4 mmHg vs 94.7 +/- 34.1 mmHg, P < 0.001). In the study period and at 14 days after cessation of Rectogesic, there was significant reduction in rectal bleeding (P = 0.0002), and significant improvement of anal pain (P = 0.0024), throbbing (P = 0.0355), pruritus (P = 0.0043), irritation (P = 0.0000) and difficulty in bowel movement (P = 0.001). The main adverse event was headache in 43.1% of patients. CONCLUSION: Rectogesic is a safe and feasible treatment for patients with early grade haemorrhoids associated with high resting anal canal pressures.

Sacral nerve stimulation induces pan-colonic propagating pressure waves and increases defecation frequency in patients with slow-transit constipation.

OBJECTIVE: Colonic propagating sequences are important for normal colonic transit and defecation. The frequency of these motor patterns is reduced in slow-transit constipation. Sacral nerve stimulation (SNS) is a useful treatment for fecal and urinary incontinence. A high proportion of these patients have also reported altered bowel function. The effects of SNS on colonic propagating sequences in constipation are unknown. Our aims were to evaluate the effect of SNS on colonic pressure patterns and evaluate its therapeutic potential in severe constipation. METHOD: In eight patients with scintigraphically confirmed slow-transit constipation, a manometry catheter (16 recording sites at 7.5 cm intervals) was positioned colonoscopically and the tip fixed in the caecum. Temporary electrodes (Medtronic) were implanted in the S2 and S3 sacral nerve foramina under general anaesthesia. In the fasted state, 14 Hz stimulation was administered and four sets of parameters (pulse width 300 or 400 micros; S2 and S3) were tested in four 2-h epochs, in random order, over 2 days. Patients were then discharged home with the sacral wires in situ and a 3-week trial stimulation commenced during which patients completed a daily stool diary. RESULTS: When compared with basal activity, electrical stimulation to S3 significantly increased pan-colonic antegrade propagating sequence (PS) frequency (5.4 +/- 4.2 vs 11.3 +/- 6.6 PS/h; P=0.01). Stimulation at S2 significantly increased retrograde PSs (basal 2.6 +/- 1.8 vs SNS 5.6 +/- 4.8 PS/h; P=0.03). During the subsequent three-week trial (continuous stimulation), six of eight reported increased bowel frequency with a reduction in laxative usage. CONCLUSION: These data demonstrate that SNS induces pan-colonic propagating pressure waves and therefore shows promise as a potential therapy for severe refractory constipation.

Rigid sigmoidoscopy: a potential hazard for cross-contamination.

BACKGROUND: Rigid sigmoidoscopy using a disposable or nondisposable sigmoidoscope is a common outpatient procedure. It has been assumed that the nondisposable bellows and light head of the sigmoidoscope remain free from enteric organisms so that the procedure is sterile if a disposable or nondisposable (metal) sigmoidoscope shaft is used. The aim of this study was to identify the presence of organisms within the bellows or light head of the sigmoidoscope. METHODS: Of 21 patients undergoing rigid sigmoidoscopy with a disposable instrument, bacterial cultures were taken from the inside of sterile Jackson-Pratt bulbs in 12 patients, with the bulbs being used to simulate the nondisposable insufflation bellows. In an additional nine patients, swabs were taken for culture from the inside of the nondisposable light head. RESULTS: Enteric gram-negative Escherichia coli and mixed anaerobic organisms were cultured from the Jackson-Pratt bulbs in two cases, and gram-positive organisms were cultured in another case. Gram-negative organisms, including Bacillus, Proteus mirabilis, Klebsiella, and Enterococcus faecalis, were cultured from the inside of the light head in two cases. CONCLUSION: Sigmoidoscopy using a disposable instrument is not a sterile procedure and may pose a risk of patient-to-patient cross-contamination by potentially harboring organisms in the bellows or light head.

Extracorporeal magnetic stimulation of the pelvic floor: impact on anorectal function and physiology. A pilot study.

PURPOSE: This study was designed to investigate the effect of extracorporeal magnetic stimulation on anorectal function and physiology. METHODS: A pilot study comparing the physiology of ten incontinent (9 females) and five continent (4 females) patients with and without perineal magnetic stimulation (10 Hz and 50 Hz) was performed. The ten incontinent patients were treated with two sessions weekly for five weeks of perineal magnetic stimulation. At treatment completion, precontinent and postcontinent scores and resting and squeeze anal pressure were compared. Patients also reported symptom improvement and satisfaction on a linear analog scale. RESULTS: The patients' mean age was 57 years. Sitting resting and squeeze anal pressures were significantly greater than lying pressures (P = 0.007, 0.047). Both 10-Hz and 50-Hz stimulation effected a significant increase in anal pressures compared with the baseline resting pressure (P = 0.005). The baseline squeeze pressures were significantly higher than the stimulated pressures compared with 50-Hz pressures (P = 0.022). After six weeks of treatment, there was a statistically significant increase in resting and squeeze anal pressures and a significant decrease in continence scores (P = 0.007, P = 0.008, P = 0.017). The mean percentage subjective improvement was 16 percent, and the mean patient satisfaction score was 3.3, positively correlating with an improvement in the continence score. CONCLUSIONS: Extracorporeal magnetic stimulation results in a significant increase in anal resting pressure irrespective of pretreatment continence. Although the subjective improvement in continence after treatment is small, there is a significant improvement in both resting pressures and patient continence scores.

Long-term follow-up of dynamic graciloplasty for faecal incontinence.

OBJECTIVE: This paper presents the long-term morbidity, function and quality of life data for patients who have undergone dynamic graciloplasty (DGP) for faecal incontinence. PATIENTS AND METHODS: All patients (n = 38) who had undergone DGP at one institution between 1993 and 2003 are presented. Thirty-three were available for long-term follow-up (median 60 months) and completed a telephone questionnaire assessing quality of life (QOL), bowel and sexual function and patient satisfaction. All patients had interval anorectal physiology studies. RESULTS: At a median follow-up of 5 years, 72% had pain, swelling or paraesthesia in the donor leg and 27% had sexual dysfunction. Sixteen percent of patients had been converted to an end-colostomy for persisting incontinence and 11% for obstructed defaecation. All other patients have a normally functioning graciloplasty. Sixteen percent of patients reported a faecal continence score < 12. Of those patients with a functioning graciloplasty, 50% had obstructed defaecation and 64% reported that their bowel dysfunction had a negative impacted on their QOL. Age, medical comorbidity and anal manometry did not correlate with functional outcome. Quality of life scores and patient satisfaction scores correlated significantly with continence scores. There was a trend toward higher QOL and satisfaction scores with conversion to colostomy compared with a continence score > 12. Sixty percent of patients rated their satisfaction with DGP as 50% or better on a visual analogue scale, and this correlated strongly with the continence score at the time of the assessment (P < 0.001). CONCLUSION: Dynamic graciloplasty significantly improves patient quality of life and anal continence for some patients. Despite increased experience, morbidity remains high and long-term continence scores are poor in a majority of cases. Obstructed defaecation is a significant problem after graciloplasty and antegrade colonic enemas may be needed. Significant prognostic factors for obstructed defaecation remain to be identified. The mechanism of both continence failure and surgical morbidity remains poorly defined in many patients and requires further investigation. The individual patient can expect a 16% chance of normal faecal continence at 5 years, with at least one surgical morbidity as a result of the procedure.

Transanal endoscopic microsurgery excision: is anorectal function compromised?

PURPOSE: Transanal endoscopic microsurgery is a new technique that has not yet found its place in routine practice. The procedure results in dilation of the anal sphincter with a large-diameter operating sigmoidoscope, sometimes for a prolonged period. The purpose of the present study was to assess the effect of transanal endoscopic microsurgery on anorectal function. METHODS: Eighteen consecutive patients undergoing transanal endoscopic microsurgery excision of rectal tumors, of whom 13 were available for evaluation, were included. Continence was scored by a numeric scale before surgery and at three and six weeks after surgery. Anorectal physiology studies were performed preoperatively and six weeks postoperatively with manometry, pudendal nerve motor terminal latency, anal mucosal electrosensitivity, rectal balloon volume studies, and endoanal ultrasound. RESULTS: There was a significant reduction in mean anal resting pressure (104 +/- 32 cm H2O before surgery, 73 +/- 30 cm H2O after surgery; P = 0.0009). There was no significant change in squeeze or cough pressure, pudendal nerve terminal motor latency, anal mucosal electrosensitivity, or rectal balloon study volumes. Fall in resting pressure was significantly correlated with length of operating time (r2 =0.39, P = 0.047). There was no significant change in mean continence score after surgery. CONCLUSION: Transanal endoscopic microsurgery results in a reduction in internal sphincter tone. This did not affect continence in a short-term study.

Neuropeptides and nerve growth in inflammatory bowel diseases: a quantitative immunohistochemical study.

Many studies have indicated changes in neuropeptides in inflammatory bowel disease (IBD), but with contradictory results. Nerve growth factor also has a potential role in the maintenance of enteric nerves and may be associated with IBD. A quantitative immunohistochemical method was used to measure area density of immunoreactive nerves in the colonic mucosa of surgical specimens. No significant differences in immunoreactivity for substance P, vasoactive intestinal polypeptide, growth associated protein 43, and the neurotrophin receptor p75 were seen in the control, Crohn's, and ulcerative colitis groups. Compared to age-matched normal colon (N = 18), there was an increase in neutrophil number in Crohn's (P < 0.05) and ulcerative colitis (P < 0.01) (both N = 9). There were positive correlations (P < 0.05) between neutrophil number and growth associated protein, between p75 and substance P immunoreactive nerves in ulcerative colitis, and between p75 and vasoactive intestinal polypeptide in Crohn's specimens. These data indicate a link between the immunologic and nervous systems in IBD.

The proximal colonic motor response to rectal mechanical and chemical stimulation.

We aimed to determine whether rectal distension and/or infusion of bile acids stimulates propagating or nonpropagating activity in the unprepared proximal colon in 10 healthy volunteers using a nasocolonic manometric catheter (16 recording sites at 7.5-cm spacing). Sensory thresholds and proximal colonic motor responses were assessed following rectal distension by balloon inflation and rectal instillation of chenodeoxycholic acid. Maximum tolerated balloon volume and the volume that stimulated a desire to defecate were both significantly (P < 0.01) reduced after rectal chenodeoxycholic acid. The frequency of colonic propagating pressure wave sequences decreased significantly in response to initial balloon inflations (P < 0.05), but the frequency doubled after subsequent chenodeoxycholic acid infusion (P < 0.002). Nonpropagating activity decreased after balloon inflation, was not influenced by acid infusion, and demonstrated a further decrease in response to repeat balloon inflation. We concluded that rectal chenodeoxycholic acid in physiological concentrations is a potent stimulus for propagating pressure waves arising in the proximal colon and reduces rectal sensory thresholds. Rectal distension inhibits all colonic motor activity.

Clostridium septicum and malignancy.

BACKGROUND: Clostridium septicum is known to be associated with malignancy or immunosuppression. It has a variable clinical presentation and is associated with a high mortality. The aim of the present study was to review the experience at St George Hospital, Sydney, over a 10-year period, with particular reference to the association of this condition with colorectal cancer. METHODS: The records of five patients with blood culture-proven Clostridium septicum infection, among a larger group of 31 patients with clostridial infections, presenting to St George Hospital between 1990 and 2000 were reviewed. RESULTS: Associated malignancy was found in four (80%) of the patients with Clostridium septicum infection. Two infections were related to colorectal cancer, two to haematological malignancies and one to radiation-induced recto-urethral fistula. Those patients who had colorectal cancer presented with septicaemia and vague abdominal symptoms. CONCLUSIONS: Clostridium septicum infections have a strong association with malignancy. When this infection occurs without an obvious underlying aetiology there should be a high index of suspicion about associated malignancy. In the absence of haematological malignancy a colonoscopy is warranted. Early diagnosis and aggressive treatment is essential in order to improve prognosis.

Do patients assess rectal bleeding accurately?

BACKGROUND: The accuracy of a patient's assessment of the volume of blood passed per rectum is unknown. The aim of the present study was to compare subjective estimations with known amounts of blood. METHODS: Thirty subjects (10 patients, 10 nurses and 10 doctors) made a visual estimation of four volumes of blood (0.25 mL, 10 mL, 50 mL, 200 mL), each placed in a standardized way into a toilet bowl. Subjects gave their estimations in mL, and also by drawing a line on a cup at the level to which they estimated that the amount of blood would fill the cup. Statistical analysis was carried out using Student's t-test. Multiple comparisons were analysed by anova. RESULTS: There was no significant difference between the groups in their estimations of each of the four volumes. Each group made a statistically significant overestimation for the 0.25 mL, 10 mL and 50 mL volumes with cup marking, as well as with estimation in mL (except for patients with the 50 mL volume, where there was a non-significant overestimation). For the 200 mL volume, patients and doctors made statistically significant underestimations with cup marking, but for nurses the underestimation did not reach significance. For the 200 mL volume estimations in mL, both nurses and doctors made underestimations that were not significant. CONCLUSIONS: Small to moderate amounts of blood in the toilet bowl are subjectively significantly overestimated, whereas larger volumes tend to be underestimated. This may have implications for the management of patients presenting with rectal bleeding.