Smoking compromises cause-specific survival in patients with operable colorectal cancer.

AIMS: To assess whether active smoking compromises survival in patients with colorectal cancer. MATERIALS AND METHODS: We studied a regionally based cohort of 284 consecutive patients referred to the Tayside Cancer Centre for consideration of adjuvant treatment after curative surgery for colorectal cancer. RESULTS: Cause-specific survival was significantly worse (P = 0.0015) in patients who were actively smoking at the time of their first post-operative visit. The absolute difference in 5-year cause-specific survival (active smokers vs the rest) was 21%. In adjusted multi-variate analysis of patients after pathologically complete (R0) resection, the hazard ratio was 2.55 (95% confidence interval 1.40-4.64) in active smokers compared with non-smokers. T stage, number of positive nodes and co-morbidity score were also of independent prognostic influence. CONCLUSIONS: Persistent smoking was, in this small series, an important and independent predictor of cancer-related death after surgery for cancer of the large bowel. Because smoking and deprivation are related, some of the adverse effects of deprivation upon survival in this group of patients may be explained by smoking behaviour.

Deprivation, comorbidity and survival in a cohort of patients with colorectal cancer.

We studied a regionally based cohort of 483 consecutive patients with colorectal cancer referred for chemotherapy and/or radiotherapy. These patients were assessed and managed according to consistent policies. We investigated the effects of socio-economic deprivation and comorbidity upon survival. Significant comorbidity was present in 48% of the patients. Overall survival and cause-specific survival were summarized using Kaplan-Meier curves. Equality of survivor functions was assessed using the logrank procedure and Cox's proportional hazards analysis. In univariate analysis, the following variables significantly affected survival: comorbidity, performance status, age and clinical stage. We could find no correlation between deprivation and comorbidity. The presence of comorbidity significantly affected cause-specific survival (3-year cause-specific survival without comorbidity 54.2%; with comorbidity 44.6%). In adjusted analysis, deprivation had an independently adverse effect on overall survival, hazard ratio 1.04 (95% confidence interval 1.00-1.08), but this was only of borderline statistical significance, P = 0.049. This study demonstrates that the interrelationships between comorbidity, deprivation and outcome in this group of patients are complex: even when care is readily available, patient assessments are uniform, and clinical decision making is consistent.

Multicentre evaluation of a commercial test for the rapid diagnosis of Clostridium difficile-mediated antibiotic-associated diarrhoea.

An immunoassay for the detection of Clostridium difficile toxin A in stool samples (Clearview C. DIFF A; Unipath, UK) was evaluated against the cell cytotoxicity assay using 407 stool samples from patients suspected to have, or considered at risk of, antibiotic-associated diarrhoea. Of the samples tested, 98 were positive and 280 were negative by both tests (sensitivity 83.1%, specificity 96.9%). Following resolution of the 29 discrepant results, the sensitivity and specificity of the immunoassay were 91% and 98%, respectively, and the sensitivity for the cell cytotoxicity assay was calculated as 91.5%, with a specificity of 99%. The Clearview C. DIFF A test proved to be a rapid simple assay for the detection of Clostridium difficile toxin A in stool samples. The test was equally suited to single or batch testing, required minimal sample handling, and provided results within 30 min of applying the sample to the test unit.

The effect of intermittent lighting on growth, feed:gain ratio, and abdominal fat content of broiler chickens of various genotypes and sex.

Intermittent lighting (IL) regimens were tested for rearing broiler chickens from 2 to 7 weeks of age. In Experiments 1 and 2, the effects of 6 cycles of light (L) and darkness (D) of 1L:3D vs. 12 cycles of .25L:1.75 D were compared on the performance of 2400 broiler chickens. Eight genotypes of 5170 mixed-sex broilers were used to compare effects of 6 cycles of 1L:3D vs. 1 cycle per day of 23.5L:.5D on broiler performance (Experiment 3). The sexes responded differently to two IL regimens in Experiment 1. Males had higher body weight, feed intake, and abdominal fat content with 1L:3D; in females, there was no difference in body weight or feed intake, but abdominal fat content was lower with 1L:3D regimen. In Experiment 2, no significant effect of lighting regimen on broiler performance was observed. In Experiment 3, most genotypes had lower feed intake and abdominal fat content for 1L:3D than for 23.5L:.5D, but response of weight gain was variable; one genotype had higher feed intake and another genotype had higher fat content with 1L:3D. It was concluded that sex and genotype should be considered in planning the use of IL techniques for broiler chickens.

The relationships of salmonellae from infected broiler flocks, transport crates or processing plants to contamination of eviscerated carcases.

Three flocks raised for broiler or roaster performance tests were studied to determine the incidence and sources of salmonellae during the growing period, transport and processing and to relate these to contamination of processed carcasses. Day old chicks in two of the tests, (tests IV and V), were treated with a culture of intestinal anaerobes derived from mature chickens. The incidence of salmonellae during the growing period was too low to permit any conclusions about the efficacy of this culture in preventing Salmonella infection, but it had no adverse effect on flock performance. Carcasses from all three flocks were contaminated with salmonellae. Although the test IV flock was raised free of salmonellae, 46% of the carcasses tested from this flock were contaminated. The apparent source was the transport crates, 99% of which yielded salmonellae before the flock was loaded. In test V, 92% of the carcasses tested yielded salmonellae. The apparent sources were: flock infection (apparently originating from the parent flock), contaminated crates, spread during transport, and plant contamination. The flock of test VI was infected with Salmonella albany, and 54% of the carcasses tested were contaminated with this serovar. Carcasses of chicks infected early in life were more likely to be contaminated than those of chickens which contacted salmonellae later in the growing period.

Flock infection and transport as sources of salmonellae in broiler chickens and carcasses.

Cultural monitoring was used to determine the incidence and sources of salmonellae in a 4160-bird broiler flock raised on litter in 32 pens. Twenty-five of the pens remained apparently free of salmonellae during the 49-day growing period. Salmonella johannesburg, first detected in the meat meal component of the starter ration, was recovered from the litter of seven pens and from the intestines of dead or culled chicks from two pens. Salmonella alachua was also recovered from two of these pens. Culture of swabs collected from the plastic crates used to transport this flock for processing showed that 97/112 (86.6%) were contaminated with salmonellae (15 serovars) before the birds were loaded. The crate washer at the plant did not remove salmonellae from these crates: 97/132 (73.5%) crates sampled after washing yielded salmonellae. Eleven serovar were recovered, including S. johannesburg and S. alachua introduced by the infected flock. Twelve of 31 chickens (38.7%) collected when the birds were unloaded at the processing plant were intestinal carriers of S. johannesburg and/or S. alachua and 29 (93.5%) were external carriers. Salmonella johannesburg, S. alachua and four other serovars were isolated from the feathers of these birds. Eleven of 25 (44%) carcasses tested from this flock yielded salmonellae. Salmonella johannesburg or S. alachua, first isolated from the infected flock, were recovered from five carcasses and S. haardt and S. Typhimurium, first isolated from the transport crates were recovered from six carcasses.

Sources of salmonellae in an uninfected commercially-processed broiler flock.

Cultural monitoring was used to study the incidence and sources of salmonellae in a 4160 bird broiler flock during the growing period, transport and processing in a commercial plant. No salmonellae were isolated from any of 132 litter samples of 189 chickens cultured during the seven-week growing period, even though nest litter samples from four of the eight parent flocks yielded salmonellae and Salmonella worthington was isolated from the meat meal component of the grower ration. On arrival at the plant, 2/23 birds sampled carried S. infantis on their feathers, although intestinal cultures failed to yield salmonellae. Three of 18 processed carcasses samples yielded salmonellae (S. infantis, S. heidelberg, S. typhimurium var copenhagen). The most likely source of these salmonellae was the plastic transport crates, since 15/107 sampled before the birds were loaded yielded salmonellae (S. infantis, S. typhimurium). The crate washer at the plant did not reduce the incidence of Salmonella-contaminated crates, since 16/116 sampled after washing yielded salmonellae (S. infantis, S. typhimurium, S. heidelberg, S. schwarzengrund, S. albany).