Patient Outcomes Following Emergency Bowel Resection for Inflammatory Bowel Disease and the Impact of Surgical Subspecialisation in the North of England: A Retrospective Cohort Study

BACKGROUND

Management of inflammatory bowel disease (IBD) has changed considerably over recent years, which has coincided with increased subspecialisation amongst general surgeons. This study evaluated the demographics and outcomes of patients with IBD undergoing bowel resection and assessed for the potential impact of surgical subspecialisation.

METHODS

Patient demographic, operative and outcome data were collected for patients undergoing a bowel resection secondary to IBD, admitted acutely to NHS trusts in the North of England between 2002 and 2016. The primary outcome of interest was 30-day post-operative mortality, with secondary outcomes: length of stay, stoma and anastomosis rates.

RESULTS

A total of 913 patients were included in the study cohort. A reduction in the number of resections was noted over time (2002-2006: 361 vs. 2012-2016: 262). No change was observed for 30-day mortality over the study period (3.9%, p = 0.233). Length of stay was also unchanged (p = 0.949). Laparoscopic surgery was increasingly utilised (0.6% vs. 17.2%, p < 0.001) in recent years, and by colorectal subspecialists (p = 0.003). More patients were managed by a colorectal consultant latterly (2002-2006: 45.4% vs. 2012-2016: 63.7%, p < 0.001). There was no difference between colorectal and other subspecialists in mortality (p = 0.156), length of stay (p = 0.201), stoma (p = 0.629) or anastomosis (p = 0.659) rates, including following multivariable adjustment.

CONCLUSION

The study demonstrated a significant reduction in the number of resections over time, increased utilisation of a laparoscopic approach and a shift towards the care of IBD surgical patients being by a colorectal subspecialist. However, these changes do not correspond with improved surgical outcomes.

Analysis of germline mutation spectra at the Huntington's disease locus supports a mitotic mutation mechanism

Trinucleotide repeat disease alleles can undergo 'dynamic' mutations in which repeat number may change when a gene is transmitted from parent to offspring. By typing >3500 sperm, we determined the size distribution of Huntington's disease (HD) germline mutations produced by 26 individuals from the Venezuelan cohort with CAG/CTG repeat numbers ranging from 37 to 62. Both the mutation frequency and mean change in allele size increased with increasing somatic repeat number. The mutation frequencies averaged 82% and, for individuals with at least 50 repeats, 98%. The extraordinarily high mutation frequency levels are most consistent with a mutation process that occurs throughout germline mitotic divisions, rather than resulting from a single meiotic event. In several cases, the mean change in repeat number differed significantly among individuals with similar somatic allele sizes. This individual variation could not be attributed to age in a simple way or to ' cis ' sequences, suggesting the influence of genetic background or other factors. A familial effect is suggested in one family where both the father and son gave highly unusual spectra compared with other individuals matched for age and repeat number. A statistical model based on incomplete processing of Okazaki fragments during DNA replication was found to provide an excellent fit to the data but variation in parameter values among individuals suggests that the molecular mechanism might be more complex.

Molecular heterogeneity of late-onset forms of globoid-cell leukodystrophy

Globoid-cell leukodystrophy (GLD) is an autosomal recessive inherited disorder caused by the deficiency of galactocerebrosidase, the lysosomal enzyme responsible for the degradation of the myelin glycolipid galactocerebroside. Although the most common form of the disease is the classical infantile form (Krabbe disease), later-onset forms also have been described. We have analyzed the galactocerebrosidase gene in 17 patients (nine families) with late-onset GLD and in 1 patient with classical Krabbe disease. Half of the patients were heterozygous for the large gene deletion associated with the 502C-->T polymorphism, the most common mutation in infantile patients. Several novel mutations that result in deficient galactocerebrosidase activity were also identified in these patients. They include the missense mutations R63H, G95S, M101L, G268S, Y298C, and I234T; the nonsense mutation S7X; a one-base deletion (805delG); a mutation that interferes with the splicing of intron 1; and a 34-nt insertion in the RNA, caused by the aberrant splicing of intron 6. All of these genetic defects are clustered in the first 10 exons of the galactocerebrosidase gene and therefore affect the 50-kD subunit of the mature enzyme. Studies on the distribution and enzymatic activity of the polymorphic alleles 1637T/C (I546/T546) provided support for previous data that had indicated the existence of two galactocerebrosidase forms with different catalytic activities in the general population. Our data also indicate that the mutations occur preferentially in the "low activity" 1637C allele.

Yeast opsonization defect and immunoglobulin deficiency in severe infantile dermatitis (Leiner's disease)

The defect in Leiner's disease, which presents in early infancy with extensive dermatitis, diarrhoea, and failure to thrive, has been attributed to a defect of the fifth component of complement (C5). We report 2 brothers with extensive dermatitis and dysgammaglobulinaemia. Both died. The older showed symptoms of Leiner's disease: C5 tests were not performed. The younger had extensive dermatitis and was found to have the C5 defect. He developed normally, but died suddenly with pertussis. We postulate that the C5 defect is not the sole cause of Leiner's disease as has been suggested, but that hypogammaglobulinaemia or other lymphoid deficiency is also required for its expression.