Phenotypic and phylogenetic segregation of Alternaria infectoria from small-spored Alternaria species isolated from wheat in Germany and Russia

AIMS

To identify the taxonomic differences between phytopathogenic small-spored Alternaria strains isolated from wheat kernels in Germany and Russia by a polyphasic approach.

METHODS AND RESULTS

Ninety-five Alternaria (A.) strains were characterized by their colony colour, their three-dimensional sporulation patterns, mycotoxin production and phylogenetic relationships based on sequence variation in translation elongation factor 1-α (TEF1-α). The examination of toxin profiles and the phylogenetic features via TEF1-α resulted in two distinct clusters, in each case containing Alternaria infectoria isolates (92 and 96% respectively) in the first and the Alternaria alternata, Alternaria arborescens and Alternaria tenuissima isolates (77 and 79% respectively) in the other combined cluster. The production of Alternariol, Altertoxin and Altenuene has not been reported previously in the A. infectoria species group. The isolates from Germany and Russia differ slightly in species composition and mycotoxin production capacity.

CONCLUSIONS

We identified that the A. infectoria species group can be differentiated from the A. alternata, A. arborescens and A. tenuissima species group by colour, low mycotoxin production and by the sequence variation in TEF1-α gene.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results allow a reliable toxic risk assessment when detecting different Alternaria fungi on cereals.

Meta-analysis of surgical outcome after enucleation versus standard resection for pancreatic neoplasms

BACKGROUND

Pancreatic enucleation is a tissue-sparing approach to pancreatic neoplasms and may result in better postoperative pancreatic function than standard pancreatic resection. The objective of this review was to compare the postoperative outcome after pancreatic enucleation versus standard resection.

METHODS

MEDLINE, Embase and the Cochrane Library were searched systematically until February 2015 to identify studies comparing the outcome of enucleation versus standard resection for pancreatic neoplasms. After critical appraisal, meta-analysis was performed and the findings were presented as odds ratios or weighted mean differences with corresponding 95 per cent c.i.

RESULTS

Twenty-two observational studies (1148 patients) were included. Duration of surgery (P < 0.001), blood loss (P < 0.001), length of hospital stay (P = 0.04), and postoperative endocrine (P < 0.001) and exocrine (P = 0.01) insufficiency were lower after enucleation than after standard resection. Mortality (P = 0.44), overall complications (P = 0.74), reoperation rate (P = 0.93) and delayed gastric emptying (P = 0.15) were not significantly different between the two approaches. The overall rate of postoperative pancreatic fistula (POPF) was higher after enucleation than after standard resection (P < 0.001). However, the raised POPF rate did not result in higher mortality or overall morbidity. Sensitivity analysis of high-volume studies (total of more than 20 enucleations and more than 4 per year) showed that, in specialized centres, enucleation can be performed with no increased risk of POPF (P = 0.12).

CONCLUSION

Compared with standard resection, pancreatic enucleation can be performed effectively and with comparable safety in high-volume institutions. Enucleation should be considered instead of standard resection for selected pancreatic neoplasms.

Pitfalls in the diagnostic evaluation of subacute combined degeneration

We report a case of a 43-year-old man presenting with a 2-week history of painless ascending sensory disturbances, suspected to be suffering from acute inflammatory polyneuropathy. On clinical examination, deep tendon reflexes were preserved and muscle strength was 5/5 everywhere. Gait was ataxic with positive Romberg test. Lumbar puncture was normal and electroneurography demonstrated demyelination. With spinal cord involvement centred on the posterior tracts on MRI, differential diagnosis focused on cobalamin deficiency. Initial laboratory work up showed nearly normal holotranscobalamin (43 pmol/L, normal>50) suggesting no vitamin B12 deficiency. Surprisingly, further testing including methylmalonic acid (3732 nmol/L, normal<271) and homocysteine (48.5 µmol/L, normal<10) showed an impairment of vitamin B12-dependent metabolism leading to the diagnosis of subacute combined degeneration. Only after repeated history taking did the patient remember having taken tablets containing cobalamin for 3 days before hospitalisation. In case of B12 deficiency, holotranscobalamin can rapidly normalise during supplementation, whereas methylmalonic acid and homocysteine might help to detect B12 deficiency in patients who recently started supplementation.

Meta-analysis of reconstruction techniques after low anterior resection for rectal cancer

BACKGROUND

Options for reconstruction after low anterior resection (LAR) for rectal cancer include straight or side-to-end coloanal anastomosis (CAA), colonic J pouch and transverse coloplasty. This systematic review compared these techniques in terms of function, surgical outcomes and quality of life.

METHODS

A systematic literature search (MEDLINE, Embase and the Cochrane Library, from inception of the databases until November 2014) was conducted to identify randomized clinical trials comparing reconstructive techniques after LAR. Random-effects meta-analyses were carried out, and results presented as weighted odds ratios or mean differences with corresponding 95 per cent c.i. A network meta-analysis was conducted for the outcome anastomotic leakage.

RESULTS

The search yielded 965 results; 21 trials comprising data from 1636 patients were included. Colonic J pouch was associated with lower stool frequency and antidiarrhoeal medication use for up to 1 year after surgery compared with straight CAA. Transverse coloplasty and side-to-end CAA had similar functional outcomes to the colonic J pouch. No superiority was found for any of the techniques in terms of anastomotic leak rate.

CONCLUSION

Colonic J pouch and side-to-end CAA or transverse coloplasty lead to a better functional outcome than straight CAA for the first year after surgery.

[Surgical options in cancer of unknown primary (CUP)]

BACKGROUND

Cancer of unknown primary site (CUP) comprises a relatively frequently occurring group of heterogeneous malignant tumors in the clinical routine, which currently has an abysmal prognosis for affected patients. Based on the improved diagnostic tools it is now possible to identify subgroups of patients with different clinical prognoses. New therapies adapted to these identified subgroups are becoming increasingly more relevant.

AIM

This review aims to evaluate the role of surgery and different surgical options in the therapy of patients with CUP.

RESULTS

For the treatment of patients with CUP it is important to identify subgroups of patients with a better prognosis. Surgical resection of CUP metastasis is a therapy option leading to a prolonged survival in (1) women with papillary peritoneal adenocarcinomatosis, (2) women with axillary lymph node metastasis of adenocarcinoma, (3) patients with cervical lymph node metastasis of squamous cell carcinoma, (4) patients with inguinal lymph node metastasis, (5) patients with poorly differentiated carcinomas with midline distribution (e.g. extragonadal germ cell syndrome) and (6) patients with small resectable tumors.

CONCLUSION

Surgery is an important therapy option in different subgroups of patients with CUP. Together with multimodal therapy, adjusted according to the identified most likely origin of the primary tumor, it is possible to prolong patient survival.

Incisional hernia rate 3 years after midline laparotomy

BACKGROUND

Incisional hernia is the most frequent long-term complication after visceral surgery, with an incidence of between 9 and 20 per cent 1 year after operation. Most controlled studies provide only short-term follow-up, and the actual incidence remains unclear. This study evaluated the incidence of incisional hernia up to 3 years after midline laparotomy in two prospective trials.

METHODS

Three-year follow-up data from the ISSAAC (prospective, multicentre, historically controlled) and INSECT (randomized, controlled, multicentre) trials focused on the rate of incisional hernia 1 and 3 years after surgery. Differences between the two groups were compared using t tests for continuous data and the χ2 test for categorical data.

RESULTS

Analysis of 775 patients included in the two trials suggested that the incisional hernia rate increased significantly from 12.6 per cent at 1 year to 22.4 per cent 3 years after surgery (P < 0.001), a relative increase of more than 60 per cent.

CONCLUSION

This follow-up of two trials demonstrated that 1 year of clinical follow-up for detection of incisional hernia is not sufficient; follow-up for at least 3 years should be mandatory in any study evaluating the rate of postoperative incisional hernia after midline laparotomy.