No abstract

Strains of Escherichia coli previously implicated or proven to be causes of diarrhea were examined for production of a toxin similar to that of Shigella dysenteriae type 1 (Shiga). Organisms grown in an iron-depleted broth were lysed by pressure disruption followed by ultracentrifugation. Saline-dialyzed extracts were tested for cytotoxic effects on HeLa cells that were neutralizable with antiserum to Shiga toxin. Among the 13 E. coli strains so analyzed, 11 made a Shiga-like cytotoxin in levels ranging from trace (two avirulent isolates) to amounts equivalent to S. dysenteriae type 1 (two noninvasive strains that did not make E. coli heat-labile or -stable enterotoxins but were isolated from infants with diarrhea). As with extracts of Shiga toxin, lysates of these E. coli strains that produced high levels of Shiga-like toxin were enterotoxic for rabbits, paralytic and lethal for mice, and inhibited protein synthesis in HeLa cells. Thus, these data suggest that Shiga-like toxin may be another heretofore undiscovered factor in the pathogenesis of diarrhea caused by some E. coli strains.

Using prognostic models, it was possible to develop a risk-stratification index that accurately predicted survival in patients presenting with malignant large bowel obstruction. The methodology and model for risk adjusted survival can set the reference point for more accurate and reliable comparative analysis and be used as an adjunct to the process of informed consent.

Birefringence relaxation studies on bovine serum albumin (BSA) reveal transient decay described by a double exponential process. The values of the relaxation times lead to estimation of the size of the equivalent ellipsoid of revolution for BSA. Previous measurements of transient birefringence for BSA have shown a single relaxation process, since the apparatus used in obtaining those data was not fast enough to detect the faster relaxation process.

The results of the study suggest that the minimum number of lymph nodes harvested in colorectal cancer surgery cannot be set at a fixed value. The lymph node harvest model provides a simple tool to the frontline clinician for comparing standards between multidisciplinary bowel cancer teams.

There is a stronger association between surgical specialization in coloproctology and beneficial outcome than with high-volume caseloads. This is not entirely accounted for by case-mix or patient population, and is seen following colonic and rectal surgery and among patients with advanced disease.

Objective: To determine the effectiveness and efficiency of the Department of Health's new general practitioner referral guidelines for bowel cancer. Design: One year prospective audit. Setting: District general hospital serving a population of 550 000. Subjects: All patients with bowel cancer; all patients referred on the basis of the two week standard and to a routine colorectal surgical outpatient clinic. Main outcome measures: Proportion of cancers referred on the basis of the two week standard and to other colorectal clinics; the proportion with the higher risk criteria and their diagnostic yields; stage of cancers diagnosed in outpatient clinics; and time to treatment. Results: A total of 249 cancers were diagnosed in the index year. Sixty five (26.1%) were referred to two week standard clinics, 40 (16.1%) to routine colorectal surgical outpatient clinics, 54 (22%) to other clinics, and 88 (35.3%) were emergencies. Thirteen patients per week were referred to the two week standard clinics and 85% (54/65) of cancers so referred were seen within two weeks. The diagnostic yield of cancer in the two week standard clinic was 9.4% (65/695) compared with 2.2% (40/1815) in the routine colorectal surgical outpatient clinic (p,0.0001). Eighty five per cent of patients with cancer referred to outpatients matched the guidelines for the two week standard clinics. Only 46% of this group were so referred. Overall, delay to treatment and Dukes' stage were not improved in patients diagnosed in the two week standard clinics. Conclusions: Most patients with bowel cancer were not referred on the basis of the two week standard although most fulfilled the referral criteria, which had higher diagnostic yields. The two week standard clinics did not shorten the overall time to treatment or improve the stage of disease because the time lags before referral and after the outpatient appointment are the major causes of delay in the bowel cancer patient's journey.

Delorme's procedure is a simple operation with satisfactory functional results which can be considered in all patients of all ages. However, high recurrence rates for primary and repeat operations should be explained to patients when planning their surgical management.