Cumulative Effective and Individual Organ Dose Levels in Paediatric Patients Undergoing Multiple Catheterisations for Congenital Heart Disease

This study examines the cumulative radiation dose levels received by a group of children who underwent multiple cardiac catheterisation procedures during the investigation and management of congenital heart disease (CHD). The purpose is to calculate cumulative doses, identify higher dose individuals, outline the inconsistencies with risk assessment and encourage the establishment of dose databases in order to facilitate the longitudinal research necessary to better understand health risks. A retrospective review of patient records for 117 paediatric patients who have undergone two or more cardiac catheterisations for the investigation of CHD was undertaken. This cohort consisted of patients who were catheterised over a period from September 2002 to August 2014. The age distribution was from newborn to 17 y. Archived kerma-area product (PKA) and fluoroscopy time (T) readings were retrieved and analysed. Cumulative effective and individual organ doses were determined. The cumulative PKA levels ranged from 1.8 to 651.2 Gycm2, whilst cumulative effective dose levels varied from 2 to 259 mSv. The cumulative fluoroscopy time was shown to vary from 8.1 to 193.5 min. Median cumulative organ doses ranged from 3 to 94 mGy. Cumulative effective dose levels are highly variable but may exceed 250 mSv. Individual organ and effective dose measurements remain useful for comparison purposes between institutions although current methodologies used for determining lifetime risks are inadequate.

Meta-analysis of the impact of surgical approach on the grade of mesorectal excision in rectal cancer

BACKGROUND

The subspecialization of colorectal surgeons, and improvements in the quality of mesorectal excision have revolutionized rectal cancer surgery. With the increasing use of minimally invasive techniques, the completeness of the mesorectal excision has been questioned. This study aimed to assess the pathological outcomes of open versus laparoscopic rectal resection.

METHODS

A meta-analysis of RCTs was undertaken. The primary endpoint was the adequacy of the mesorectal excision. Secondary endpoints included circumferential resection margin and distance to resection margins.

RESULTS

Four studies were included, reporting on 2319 patients; 972 (41·9 per cent) had open and 1347 (58·1 per cent) had laparoscopic resections. Meta-analysis of adequacy of the mesorectal excision showed a small difference in achieving an intact mesorectum in favour of open surgery (risk ratio (RR) 1·06, 95 per cent c.i. 1·02 to 1·10; P = 0·001). Superficial defects were more common in laparoscopic surgery (RR 0·70, 0·54 to 0·89; P = 0·004). Deep mesorectal defects (RR 0·78, 0·51 to 1·20; P = 0·256), circumferential margin (CRM) positivity (RR 0·85, 0·62 to 1·16; P = 0·310), and distance to radial (mean difference (MD) -0·06, 95 per cent c.i. -0·10 to 0·23; P = 0·443) and distal (MD 0·03, -0·06 to 0·12; P = 0·497) margins were all similar. A complete resection (intact mesorectum, negative CRM and distal margin) was achieved in 350 of 478 patients (73·2 per cent) in the laparoscopic group and 372 of 457 (81·4 per cent) in the open group (risk difference (RD) 8 (95 per cent c.i. 3 to 13) per cent; P = 0·003). However, an acceptable mesorectum (intact or superficial defects only) was present in 1254 of 1308 (95·9 per cent) and 916 of 949 (96·5 per cent) in the laparoscopic and open groups respectively (RD 1 (-1 to 3) per cent; P = 0·263).

CONCLUSION

Small differences in mesorectal quality were evident between open and laparoscopic rectal resections. This may be attributable to use of laparoscopic instruments; however, to date minor defects have not affected oncological outcomes.

Prophylactic Ureteric Stents in Renal Transplant Recipients: A Multicenter Randomized Controlled Trial of Early Versus Late Removal

Prophylactic ureteric stenting in renal transplantation reduces major urological complications; however, morbidity is related to the indwelling duration of a stent. We aimed to determine the optimal duration for stents in this clinical setting. Patients (aged 2-75 years) from six UK hospitals who were undergoing renal transplantation were recruited and randomly assigned to either early stent removal at 5 days (without cystoscopy) or late removal at 6 weeks after transplantation (with cystoscopy). The primary outcome was a composite of stent-related complications defined as pain, visible hematuria, migration, fragmentation, and urinary tract infections (UTIs) within 3 mo of transplantation. Between May 2010 and Nov 2013, we randomly assigned 227 participants, with 205 included in the final analysis of the primary outcome. Stent-related complications were significantly higher in the late versus early stent removal groups (36 of 126 [28.6%] vs. 6 of 79 [7.6%]; p < 0.001). The majority of stent complications consisted of UTIs, with an incidence of 31 of 126 (24.6%) in the late group compared with 6 of 79 (7.6%) in the early group (p = 0.004). We found early stent removal on day 5 significantly reduced stent-related complications and improved quality of life in the first 3 mo after transplantation (ISRCTN09184595).

The use of a micropore particle technology in the treatment of acute wounds

OBJECTIVE

A clinical audit was performed to evaluate whether Acapsil micropore particle technology (MPPT) powder could improve the management of acute wounds to heal by secondary intention.

METHOD

Wounds, which could be characterised as sloughy, wet and probably infected, normally managed by debridement followed by negative pressure wound therapy (NPWT), were included in the evaluation. The MPPT powder was applied topically to the wound surface either once daily or on alternate days, with each wound receiving a total of two to five applications. Most patients had NPWT after the MPPT powder treatment had finished to assist healing.

RESULTS

The study included nine patients with dehisced surgical wounds and one with a category IV pressure ulcer (PU). The wounds were generally covered in slough, exudate and showing signs of local infection. The topical MPPT powder rapidly desloughed the wounds, controlled exudate levels, promoted granulation and was well tolerated. All wounds proceeded towards closure.

CONCLUSION

Comparison of the present data with MPPT powder to standard treatment suggests that the speed of healing using MPPT was improved. Further examination is required to determine if this reduces dressing changes, nursing time, and financial cost.

CONTEMPORARY AUSTRALIAN DOSE AREA PRODUCT LEVELS IN THE FLUOROSCOPIC INVESTIGATION OF PAEDIATRIC CONGENITAL HEART DISEASE

This study examines radiation dose levels delivered to children from birth to 15 y of age in the investigation of congenital heart disease (CHD) at a major Sydney children's hospital. The aims are to compare values with those derived from similar studies, to provide a template for more consistent dose reporting, to establish local and national diagnostic reference levels and to contribute to the worldwide paediatric dosimetry database. A retrospective review of 1007 paediatric procedural records was undertaken. The cohort consisted of 795 patients over a period from January 2007 to December 2012 who have undergone cardiac catheterisation for the investigation of CHD. The age range included was from the day of birth to 15 y. Archived dose area product (DAP) and fluoroscopy time (FT) readings were retrieved and analysed. The mean, median, 25th and 75th percentile DAP levels were calculated for six specific age groupings. The 75th percentile DAP values for the specific age categories were as follows: 0-30 d-1.9 Gy cm2, 1-12 months-2.9 Gy cm2, 1-3 y-5.3 Gy cm2, 3-5 y-6.2 Gy cm2, 5-10 y-7.5 Gy cm2 and 10-15 y-17.3 Gy cm2. These levels were found to be lower than the values reported in comparable overseas studies. Individual year-specific levels were determined, and it is proposed that these are more useful than the common grouping method. The age-specific 75th percentile DAP levels outlined in this study can be used as baseline local diagnostic reference levels. The needs for the standardisation of DAP reporting and for a greater range of age-specific diagnostic reference levels have been highlighted. For the first time, Australian dose values for paediatric cardiac catheterisation are presented.

Hypoxia determines survival outcomes of bacterial infection through HIF-1alpha dependent re-programming of leukocyte metabolism

Hypoxia and bacterial infection frequently co-exist, in both acute and chronic clinical settings, and typically result in adverse clinical outcomes. To ameliorate this morbidity, we investigated the interaction between hypoxia and the host response. In the context of acute hypoxia, both S. aureus and S. pneumoniae infections rapidly induced progressive neutrophil mediated morbidity and mortality, with associated hypothermia and cardiovascular compromise. Preconditioning animals through longer exposures to hypoxia, prior to infection, prevented these pathophysiological responses and profoundly dampened the transcriptome of circulating leukocytes. Specifically, perturbation of HIF pathway and glycolysis genes by hypoxic preconditioning was associated with reduced leukocyte glucose utilisation, resulting in systemic rescue from a global negative energy state and myocardial protection. Thus we demonstrate that hypoxia preconditions the innate immune response and determines survival outcomes following bacterial infection through suppression of HIF-1α and neutrophil metabolism. The therapeutic implications of this work are that in the context of systemic or tissue hypoxia therapies that target the host response could improve infection associated morbidity and mortality.

Retrievable IVC filters - Friend or foe

Venous thromboembolism is a common condition with widely varied outcomes. Pulmonary embolism is associated with a case-fatality rate of up to 8%, increasing up to 18-fold in massive PE. Pharmacological treatment of VTE with anticoagulant medication (AC) is the first line therapy of choice. Retrievable inferior vena cava filters (IVCF) are indicated as a short-term replacement for AC in certain circumstances. Most of the evidence concerning IVCF pertains to permanent filters and older filter models. Limited evidence for retrievable IVCF results in poor consensus regarding indications, follow-up and retrieval. Complications increase with dwell-time and retrieval success rates decline. Professional bodies advocate strict guideline adherence and robust strategies for filter monitoring to maximise retrieval rate.

Perampanel: An audit of clinical experience using the epilepsy electronic patient record

Perampanel is a non-competitive antagonist of AMPA glutamate receptors on post synaptic neurons. The aim of this study was to conduct an audit of the experience of perampanel treatment in Ireland based on the interrogation of the national epilepsy electronic patient record (EPR). A retrospective audit was compiled which reviewed the progress of patients who had been treated across two regional epilepsy centres. The EPR was used to identify patients and collect information relevant to their perampanel therapy. Collected data was entered into a statistical package for social sciences for analysis using descriptive statistics. Seventy patients were identified for inclusion in this audit. Partial onset epilepsy was the predominant epilepsy syndrome treated with perampanel. Eight milligrams daily was the maximum dose achieved in 31.45% (n=22). Complex partial seizures demonstrated the best seizure response to perampanel, which was optimal at doses of 4mgs to 8mgs once daily. Treatment was discontinued primarily due to side effect profile (28.5%; n=20). The common side effects reported were behavioural alteration, sedation and dizziness. Abnormal thoughts were identified in 4.2% (n=3). Overall perampanel has been shown to be an effective adjunct. The EPR was demonstrated as an effective tool for audit and research.

Microsatellite instability is associated with reduced disease specific survival in stage III colon cancer

BACKGROUND

Up to 15% of colorectal cancers exhibit microsatellite instability (MSI), where errors in replication go unchecked due to defects in the mismatch repair system. This study aimed to determine survival in a large single-centre series of 1250 consecutive colorectal cancers subjected to universal MSI testing.

METHODS

Clinical and pathological features of patients with colorectal cancer identified on prospectively maintained colorectal and pathology databases at St. Vincent's University Hospital from 2004 to May 2012 were examined. Mismatch repair (MMR) status was determined by immunohistochemistry. Kaplan-Meier curves, the log-rank test and Cox regression were used to associate survival with clinical and pathological characteristics.

RESULTS

Of the 1250 colorectal cancers in the study period, 11% exhibited MSI (n = 138). Patients with MSI tumours had significantly lower rates of lymph node and distant metastases (MSI N+ rate: 24.8% compared with MSS N+ rate: 46.2%, p < 0.001). For Stage I and II disease MSI was associated with improved disease free survival (DSS) compared with MSS colon cancer. However, patients with Stage III MSI colon cancers had a worse DSS than those with MSS tumours. Stage III MSI tumours exhibited higher rates of lymphovascular invasion and perineural invasion than Stage I/II MSI tumours.

CONCLUSION

MSI is associated with a reduced risk of nodal and distant metastases, with an improved DSS in Stage I/II colon cancer. However, when MSI tumours progress to Stage III these patients had worse outcomes and pathological features. New strategies for this cohort of patients may be required to improve outcomes.

Bovine Staphylococcus aureus: Subtyping, evolution, and zoonotic transfer

Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies using ribosomal spacer (RS)-PCR, however, demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infections are genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. Furthermore, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. In addition to RS-PCR, other methods for subtyping Staph. aureus are known, including spa typing and multilocus sequence typing (MLST). They are based on sequencing the spa and various housekeeping genes, respectively. The aim of the present study was to compare the 3 analytic methods using 456 strains of Staph. aureus isolated from milk of bovine intramammary infections and bulk tanks obtained from 12 European countries. Furthermore, the phylogeny of animal Staph. aureus was inferred and the zoonotic transfer of Staph. aureus between cattle and humans was studied. The analyzed strains could be grouped into 6 genotypic clusters, with CLB, CLC, and CLR being the most prominent ones. Comparing the 3 subtyping methods, RS-PCR showed the highest resolution, followed by spa typing and MLST. We found associations among the methods but in many cases they were unsatisfactory except for CLB and CLC. Cluster CLB was positive for clonal complex (CC)8 in 99% of the cases and typically positive for t2953; it is the cattle-adapted form of CC8. Cluster CLC was always positive for tbl 2645 and typically positive for CC705. For CLR and the remaining subtypes, links among the 3 methods were generally poor. Bovine Staph. aureus is highly clonal and a few clones predominate. Animal Staph. aureus always evolve from human strains, such that every human strain may be the ancestor of a novel animal-adapted strain. The zoonotic transfer of IMI- and milk-associated strains of Staph. aureus between cattle and humans seems to be very limited and different hosts are not considered as a source for mutual, spontaneous infections. Spillover events, however, may happen.

Staphylococcus aureus genotype B and other genotypes isolated from cow milk in European countries

Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies, however, have demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infection is genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. In addition, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. The aim of this study was to subtype strains of Staph. aureus isolated from bovine mastitic milk and bulk tank milk to obtain a unified view of the presence of bovine staphylococcal subtypes in 12 European countries. A total of 456 strains of Staph. aureus were subjected to different typing methods: ribosomal spacer PCR, detection of enterotoxin genes, and detection of gene polymorphisms (lukE, coa). Major genotypes with their variants were combined into genotypic clusters (CL). This study revealed 5 major CL representing 76% of all strains and comprised CLB, CLC, CLF, CLI, and CLR. The clusters were characterized by the same genetic properties as the Swiss isolates, demonstrating high clonality of bovine Staph. aureus. Interestingly, CLB was situated in central Europe whereas the other CL were widely disseminated. The remaining 24% of the strains comprised 41 genotypes and variants, some of which (GTAM, GTBG) were restricted to certain countries; many others, however, were observed only once.

Correlates of hepcidin and NTBI according to HFE status in patients referred to a liver centre

BACKGROUND/AIMS

Innately low hepcidin levels lead to iron overload in HFE-associated hereditary haemochromatosis.

METHODS

This study compared hepcidin and non-transferrin bound iron (NTBI) levels in untreated iron-loaded and non-iron-loaded C282Y homozygotes to levels in C282Y/H63D compound heterozygotes and individuals with other HFE genotypes associated with less risk of iron overload.

RESULTS

As the genotypic risk for iron overload increased, transferrin saturation and serum NTBI levels increased while serum hepcidin levels decreased. Overweight and obese male C282Y homozygotes had significantly higher hepcidin levels than male C282Y homozygotes with a normal BMI. Pearson product-moment analysis showed that serum hepcidin levels significantly correlated with HFE status, serum ferritin, age, NTBI, transferrin saturation, gender and BMI. Subsequent multiple regression analysis showed that HFE status and serum ferritin were significant independent correlates of serum hepcidin levels.

CONCLUSIONS

In summary, this study has shown that while serum ferritin and HFE status are the most important determinants of hepcidin levels, factors such age, gender, BMI, transferrin saturation and NTBI all interact closely in the matrix of homeostatic iron balance.