Tumor-Induced Osteomalacia in a Patient with Crohn's Disease: A Case Report and Approach to Investigating Hypophosphatemia

Introduction

Hypophosphatemia occurs commonly in inflammatory bowel disease (IBD) patients and can cause considerable morbidity. The differential diagnoses in IBD include nutritional causes and hypophosphatemia induced by some formulations of intravenous iron infusions.

Case Presentation

We present the case of a 37-year-old man with active Crohn's disease, presenting with difficulty walking and fractures of the vertebrae and calcaneus. He had long-standing hypophosphatemia. Nutritional causes for hypophosphatemia were considered in the first instance given the presence of chronic diarrhea and vitamin D deficiency; however, there was minimal response to appropriate supplementation with oral phosphorous and vitamin D. Iron infusion-induced hypophosphatemia was then considered, but the nadir phosphate level preceded any iron infusion. Therefore, work-up was undertaken for less common causes. He was ultimately diagnosed with tumor-induced osteomalacia, caused by excess fibroblast growth factor 23 (FGF23) secretion from a phosphaturic mesenchymal tumor about the knee. He had complete resolution of symptoms and biochemical abnormalities following successful resection of the tumor.

Conclusion

This case illustrates the approach to investigation of hypophosphatemia in IBD patients. If the time course and response to phosphate supplementation are not as expected for nutritional or iron infusion-induced hypophosphatemia, less common causes should be considered.

Heart failure is associated with low circulating levels of secreted frizzled receptor protein 5 (Sfrp5)

Background/Introduction

Obesity and metabolic dysregulation are closely associated with the pathophysiology of multiple cardiovascular diseases (CVD). To date, the pathophysiological mechanism(s) of obesity and its link with cardiovascular systems remain largely unknown. Adipose tissue inflammation as a result of excessive fat expansion in obesity, leading to increased systemic production of growth factors and recruitment of inflammatory cells have been postulated to be a major factor. Secreted frizzled-related protein 5 (SFRP5) is an anti-inflammatory adipokine that is linked with obesity and metabolic regulation and has been indicated to affect cardiovascular functions. Currently, the role of circulating SFRP5 levels as a biomarker for cardiovascular diseases are poorly understood, with studies yielding discordant results.

Purpose

This study aims to evaluate the relationship between circulating SFRP5 and cardiovascular functions in a cohort of patients with established CVD.

Methods

Patients (n=262, 148 male (56.5%), age (68±11 yrs)) presenting to the cardiology unit for cardiovascular investigations were recruited into the study. Plasma SFRP5 levels were measured via enzyme-linked immunosorbent assay (ELISA). Associations between plasma SFRP5 levels, cardiovascular functions, and patients' co-morbidities were analysed using univariate and multivariate analyses.

Results

Plasma SFRP5 levels were significantly lower in patients presenting with: heart failure (HF) vs non-HF (median; (10.7 vs 31.0; p<0.001); coronary artery disease (CAD) vs non-CAD; (11.0 vs 33.8; p<0.001); and atrial fibrillation (AF) vs non-AF; (11.2 vs 23.2; p=0.001). On univariate analyses, SFRP5 levels also significantly positively correlated with left ventricular ejection fraction (LVEF) (r=0.52, p<0.001), estimated glomerular filtration rate (eGFR) (r=0.16, p=0.02), total cholesterol levels and triglycerides (r=0.29, p<0.001; r=0.17, p<0.01 respectively). Low SFRP5 levels were correlated with high C-reactive protein (CRP) and E/E' (r=−0.29, p<0.001, r=−0.30, p<0.001, respectively). Patients with HF, CAD, statin use, low LVEF, low triglycerides, high CRP and high eGFR were associated with lower SFRP5 levels independent of age, BMI or diabetes on multivariate analysis (overall model r=0.729, SE=0.638).

Conclusion

Our results show that low plasma SFRP5 levels are independently associated with HF, CAD, and impaired systolic and diastolic functions. These results suggest that SFRP5 may regulate cardiovascular functions independent of obesity and metabolic regulations.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Heart Foundation of Australia Future Leader FellowshipsNSW Ministry of Health EMC FellowshipHeart Foundation of Australia Future Leader Fellowship

Mechanism(s) for age-related sex differences in diet-induced cardiomyopathy: role of RNA methylation

Background/Introduction

Age and sexual dimorphism contribute to the differential cardiometabolic dysfunctions associated with diet-induced obesity. However, the underlying mechanisms remain elusive. RNA modifications via RNA m6A methylation, is an emerging mediator of RNA stability, translation and localization responsible for regulation of multiple biological functions. RNA m6A modifications are regulated by “writers”, “erasers” and “readers”. The role of RNA methylation machinery genes in the heart is largely unexplored, and may provide insight into the influence of age and sex on cardiometabolic dysfunction.

Purpose

We aim to determine differential RNA methylation changes within the heart in a diet-induced cardiomyopathy mouse model, stratified according to age and sex.

Methods

Male and female C57BL/6 mice (6–8wk-old) were fed normal chow (NC) or high-fat/high-sucrose (HFHS) diet for 1 or 4 months. Echocardiographic measurements were performed at 1 and 4 months according to the American Society of Echocardiography and European Association of Cardiovascular Imaging guidelines. At study endpoint, glucose and insulin tolerance testing was conducted by injecting mice intraperitoneally with 2g/kg glucose or 0.6U/kg insulin, and monitoring blood glucose levels over a 2 hour period. RNA from heart tissue was subjected to quantitative PCR for RNA methylation machinery genes (FTO, ALKBH5, METTL3, METTL4, METTL14, YTHDF1 and YTHDF2). PPIA was used to normalise qPCR data.

Results

Both male and female mice showed evidence of age- and diet-induced metabolic dysfunction, however, males and females showed markedly different metabolic impairments. For example, glucose tolerance was exacerbated by 4 months of HFHS diet in males but not females; and only females showed impaired insulin tolerance. Echocardiography showed that males had systolic (stoke volume, cardiac output) and diastolic (E/A ratio) dysfunction after 4 months of HFHS diet, while females were unperturbed. We identified that METTL3 and METTL14, the “writers” of m6A methylation, were consistently increased in male mouse hearts at 1 vs 4 months of age but were unchanged or decreased in females, irrespective of diet. Conversely, YTHDF1, a “reader”, was unchanged in male mouse hearts at 1 vs. 4 months of age but was significantly increased in female hearts.

Conclusion

Our study confirms that markedly different cardiometabolic impairments occur in male versus female mice in response to long-term HFHS diet. Despite significant metabolic impairment in both sexes, cardiac dysfunction was only evident in males. RNA methylation machinery genes were differentially expressed in mouse hearts according to age and sex, suggesting that RNA methylation may be involved in age-related sexual dimorphism in cardiometabolic impairments.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Heart Foundation

Doxorubicin-induced upregulation of follistatin-like 3 (FSTL3): a new therapeutic target

Introduction

Doxorubicin (DOX) is among the most used anticancer drugs with associated cardiotoxicity. Follistatin-like 3 (FSTL3), a secreted member of the follistatins family that can selectively bind to members of the TGF-β superfamily, is involved in regulation of cardiac hypertrophy and heart failure. FSTL3 is also upregulated in breast and colorectal cancer tumours, is also an unfavourable prognostic indicator for various cancers.

Purpose

We aim to determine the dual role of FSTL3 in prevention of DOX-induced cardiotoxicity and synergistic anti-cancer effects.

Methods

Human cardiomyocytes (HCMs) were treated with DOX at 1uM (EC50) for 72 hours. Cell viability was assessed via CellTiter-Glo®. Secreted FSTL3 levels, as measured by ELISA (R&D systems). FSTL3 and TGF-β mRNA levels were measured by qPCR. Co-treatment of DOX with human anti-FSTL3 antibodies (Aviva Systems Biology) at 10ug/mL were introduced for 72hrs treatment.

Results

Secreted FSTL3 levels were significantly increased in DOX-treated HCMs at 72hrs compared to control (n=5, p<0.001). Consistently, FSTL3 and TGF-β mRNA levels, in collected HCMs were significantly increased in DOX-treated cells. Co-treatment of DOX with human anti-FSTL3 antibodies at 10ug/mL significantly improved HCM viability compared to IgG control group. Conversely, anti-FSTL3 antibodies provided synergistic anti-cancer effects with DOX: MCF-7 breast cancer cells were significantly reduced when co-treated with DOX and anti-FSTL3 antibody vs. IgG controls.

Conclusion

We show, for the first time, that: 1) FSTL3 is secreted directly from HCMs; 2) FSTL3 levels (both circulating and mRNA) is markedly elevated with DOX treatment; 3) neutralisation of FSTL3 in DOX-treated HCMs, restored HCM viability; and 4) exhibit synergistic anti-cancer effects with DOX. Taken together, FSTL3 is a potential target for dual anti-cancer and cardioprotective effects.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Heart Foundation of Australia Future Leader FellowshipsNSW Ministry of Health EMC FellowshipNSW Ministry of Health Translational Research Grant

Viral Enteric Infections in Acute Severe Ulcerative Colitis

BACKGROUND AND AIMS

Excluding superimposed enteric infection is critical in the management of acute severe ulcerative colitis [ASUC]. Whilst infection with Clostridium difficile and cytomegalovirus have been shown to increase colectomy and mortality rates, no data exist regarding the impact of common viral enteropathogens in ASUC. Our aim was to determine if viral enteric infection in ASUC alters the severity or outcomes of these episodes.

METHODS

This was a retrospective review of cases presenting to a large tertiary centre. Data were obtained from an in-house, prospectively maintained inflammatory bowel disease database. We identified all ASUC cases treated between October 2015 and January 2021 and compared those testing positive for adenovirus 40/41, human rotavirus or norovirus GI by faecal multiplex polymerase chain reaction [PCR] to those testing negative.

RESULTS

We identified 147 patients with ASUC and faecal multiplex PCR testing for viral pathogens. In total, 22/147 patients [14.9%] tested positive, two of whom tested positive for two viruses. The infected and non-infected cohorts did not differ significantly with regard to admission C-reactive protein [81.7 vs 76.6, p = 0.77], Mayo endoscopic subscore [2.4 vs 2.3, p = 0.43], length of hospital admission [7.9 vs 7.9 p = 0.99], requirement for rescue therapy [59% vs 56%, p = 0.75] or colectomy rate [4.5% vs 4.1%, p = 0.69].

CONCLUSIONS

Infection with viral enteropathogens was common in our ASUC cohort, but did not appear to affect disease severity at presentation, the need for rescue therapy or the success rate of rescue therapy.

Markers of Systemic Inflammation in Acute Attacks of Ulcerative Colitis: What Level of C-reactive Protein Constitutes Severe Colitis?

BACKGROUND AND AIMS

The erythrocyte sedimentation rate [ESR] as a component of the Truelove and Witts Criteria [TWC] is the traditional inflammatory marker used for the assessment of ulcerative colitis [UC] activity. However, the C-reactive protein [CRP] is preferentially used in contemporary clinical practice. We aimed to determine the equivalent CRP cut-off for an ESR of  >30 mm/h in patients presenting with acute severe UC.

METHODS

Clinical and pathological data were prospectively collected from 163 presentations of severe UC. A CRP cut-off corresponding to an ESR of  >30 mm/h was determined using confusion matrices. A validation cohort of 128 presentations was prospectively collected and analysed.

RESULTS

A CRP cut-off of ≥12 mg/L generated an 85% positive predictive value [PPV] with a sensitivity of 95% and an accuracy of 82% for having a paired ESR of  >30 mm/h. There were no statistically significant differences between groups determined by the traditional ESR versus the new CRP-based criterion in the presenting faecal calprotectin, Mayo endoscopic subscore, or the rates of intravenous corticosteroid therapy failure and colectomy-by-discharge. Applying the CRP  ≥12 mg/L criterion to a validation cohort of 128 presentations generated a PPV of 83% and a sensitivity of 94%.

CONCLUSIONS

The proposed CRP  ≥12 mg/L cut-off is an inclusive, sensitive, and very practical alternative to ESR as part of the TWC for defining UC presentation severity. It demonstrated similar performance characteristics to the classical ESR criterion when used for the assessment of acute UC disease activity. These findings were confirmed in a validation cohort.

Outcomes of dietary management approaches in active ulcerative colitis: A systematic review

BACKGROUND & AIMS

The dietary management of active ulcerative colitis (UC) is currently poorly understood. Due to the lack of clinical guidelines for this population, diet choice may be based on the personal judgement of the clinician, and without sound evidence. The aim of this systematic review was to appraise the current literature on the dietary management of individuals with active UC, in both inpatient and outpatient settings, to determine if clinical outcomes differ by diet prescription.

METHOD

PUBMED, CINAHL, EMBASE, Web of Science and SCOPUS were comprehensively searched during March and April 2020. Eligible trials recruited adults with active UC comparing different methods of dietary management, including enteral nutrition (EN), total parenteral nutrition (TPN), elimination diets and standard oral diets, in both the inpatient and outpatient settings.

RESULTS

10 studies met inclusion criteria of this qualitative synthesis. No difference was found between EN, TPN and bowel rest in terms of disease activity measures when compared to a standard oral diet. The results of this study also showed promising potential for the use of elimination diets in the outpatient setting with four studies finding a significant difference in disease activity measures between the intervention diet and control.

CONCLUSION

There is no strong evidence to support the use of any specific dietary prescription to improve clinical outcomes for individuals with active UC. A number of low quality studies suggest benefit of following an elimination diet, however, additional high quality studies are required before any more specific recommendations can be made.

Follistatin-like 3 (FSTL3) levels are increased in acute heart failure patients

Introduction

Follistatin-like 3 (FSTL3) is a secreted protein that has been suggested to play an important role in modulating cardiac remodeling and hypertrophy. In this study, we aim to determine whether: 1) FSTL3 is incrementally elevated in patients with HF vs those with other cardiovascular disease (CVD); and 2) increased FSTL3 is associated with 2 or more hospital admissions due to major adverse CV events (MACE) within 1 year.

Methods and results

We measured circulating levels of FSTL3 using commercially available ELISA (R&D systems) in a total of n=696 patients. FSTL3 levels were compared between: 1) healthy-aging volunteers with no prior major CVD (n=267, age 67±6 years) and 2) patients admitted to cardiology unit for various CVD (n=429, age 66±14 years); among those (n=178, age 68±13 years) had HF. Patients with HF had 2-fold higher FSTL3 levels vs healthy age-matched controls vs those with other CVD (p<0.001). Occurrences of MACE were recorded up to 1 year for patients admitted to cardiology unit. On univariate analyses, patient with 2 or more MACE within 1 year (n=91, 27%) had significant elevated FSTL3 levels (P=0.003), is associated with older age (P<0.005). On multivariate analysis, high FSTL3 levels (P=0.034) is an independent predictor of 2 or more MACE admissions within 1 year after adjusting for age, clinical comorbidities and medications.

Conclusions

FSTL3 is incrementally increased in patients with HF and is associated with poorer prognosis. Elevated FSTL3 levels is associated with increased risks of cardiac hospital readmissions for patients with multiple CV morbidities.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NSW Ministry of Health EMC Fellowship (Australia)

A Pseudo-Outbreak of Skin Disease in British Troops

When a newspaper report claimed that a serious outbreak of skin disease had occurred in British Army troops stationed at the Bočac Dam, in western Bosnia, all troops at the Bočac Dam location (n=96), followed by a matched control group of troops (n=91) at a nearby location, were examined by two investigators.

14% of the study population and 21% of the control group were found to have skin disorders. Most were complaints that are commonly encountered in general medical practice. There was a striking absence of skin infestations. The historical consultation rate for skin disorders had not increased. It was concluded that an outbreak of skin disease had not occurred in British troops guarding the dam.

This epidemiological study shows that, even under conditions of modern field hygiene, up to one in five soldiers will have skin disease. Skin infestations, however, have become progressively less common during military campaigns this century, probably because of better personal hygiene, good preventive medicine practices and better access to effective health care.

A Method to Exploit the Structure of Genetic Ancestry Space to Enhance Case-Control Studies

One goal of human genetics is to understand the genetic basis of disease, a challenge for diseases of complex inheritance because risk alleles are few relative to the vast set of benign variants. Risk variants are often sought by association studies in which allele frequencies in case subjects are contrasted with those from population-based samples used as control subjects. In an ideal world we would know population-level allele frequencies, releasing researchers to focus on case subjects. We argue this ideal is possible, at least theoretically, and we outline a path to achieving it in reality. If such a resource were to exist, it would yield ample savings and would facilitate the effective use of data repositories by removing administrative and technical barriers. We call this concept the Universal Control Repository Network (UNICORN), a means to perform association analyses without necessitating direct access to individual-level control data. Our approach to UNICORN uses existing genetic resources and various statistical tools to analyze these data, including hierarchical clustering with spectral analysis of ancestry; and empirical Bayesian analysis along with Gaussian spatial processes to estimate ancestry-specific allele frequencies. We demonstrate our approach using tens of thousands of control subjects from studies of Crohn disease, showing how it controls false positives, provides power similar to that achieved when all control data are directly accessible, and enhances power when control data are limiting or even imperfectly matched ancestrally. These results highlight how UNICORN can enable reliable, powerful, and convenient genetic association analyses without access to the individual-level data.

INPP4B is an oncogenic regulator in human colon cancer

Inositol polyphosphate 4-phosphatase type II (INPP4B) negatively regulates phosphatidylinositol 3-kinase signaling and is a tumor suppressor in some types of cancers. However, we have found that it is frequently upregulated in human colon cancer cells. Here we show that silencing of INPP4B blocks activation of Akt and serum- and glucocorticoid-regulated kinase 3 (SGK3), inhibits colon cancer cell proliferation and retards colon cancer xenograft growth. Conversely, overexpression of INPP4B increases proliferation and triggers anchorage-independent growth of normal colon epithelial cells. Moreover, we demonstrate that the effect of INPP4B on Akt and SGK3 is associated with inactivation of phosphate and tensin homolog through its protein phosphatase activity and that the increase in INPP4B is due to Ets-1-mediated transcriptional upregulation in colon cancer cells. Collectively, these results suggest that INPP4B may function as an oncogenic driver in colon cancer, with potential implications for targeting INPP4B as a novel approach to treat this disease.

Smoking behaviour modifies IL23r-associated disease risk in patients with Crohn's disease

BACKGROUND AND AIM

The etiology of Crohn's disease (CD) implicates both genetic and environmental factors. Smoking behavior is one environmental risk factor to play a role in the development of CD. The study aimed to assess the contribution of the interleukin 23 receptor (IL23R) in determining disease susceptibility in two independent cohorts of CD, and to investigate the interactions between IL23R variants, smoking behavior, and CD-associated genes, NOD2 and ATG16L1.

METHODS

Ten IL23R single-nucleotide polymorphisms (SNPs) were genotyped in 675 CD cases, and 1255 controls from Brisbane, Australia (dataset 1). Six of these SNPs were genotyped in 318 CD cases and 533 controls from Canterbury, New Zealand (dataset 2). Case-control analysis of genotype and allele frequencies, and haplotype analysis for all SNPs was conducted.

RESULTS

We demonstrate a strong increased CD risk for smokers in both datasets (odds ratio 3.77, 95% confidence interval 2.88-4.94), and an additive interaction between IL23R SNPs and cigarette smoking. Ileal involvement was a consistent marker of strong SNP-CD association (P ≤ 0.001), while the lowest minor allele frequencies for location were found in those with colonic CD (L2). Three haplotype blocks were identified across the 10 IL23R SNPs conferring different risk of CD. Haplotypes conferred no further risk of CD when compared with single SNP analyses.

CONCLUSION

IL23R gene variants determine CD susceptibility in the Australian and New Zealand population, particularly ileal CD. A strong additive interaction exists between IL23R SNPs and smoking behavior resulting in a dramatic increase in disease risk depending upon specific genetic background.

Crohn's disease and smoking: is it ever too late to quit?

BACKGROUND

Smoking increases CD risk. The aim was to determine if smoking cessation at, prior to, or following, CD diagnosis affects medication use, disease phenotypic progression and/or surgery.

METHODS

Data on CD patients with disease for ≥5 yrs were collected retrospectively including the Montreal classification, smoking history, CD-related abdominal surgeries, family history, medication use and disease behaviour at diagnosis and the time when the disease behaviour changed.

RESULTS

1115 patients were included across six sites (mean follow-up-16.6 yrs). More non-smokers were male (p=0.047) with A1 (p<0.0001), L4 (p=0.028) and perianal (p=0.03) disease. Non-smokers more frequently received anti-TNF agents (p=0.049). (p=0.017: OR 2.5 95%CI 1.18-5.16) and those who ceased smoking prior to diagnosis (p=0.045: OR 2.3 95%CI 1.02-5.21) progressed to complicated (B2/B3) disease as compared to those quitting at diagnosis. Patients with uncomplicated terminal ileal disease at diagnosis more frequently developed B2/B3 disease than isolated colonic CD (p<0.0001). B2/B3 disease was more frequent with perianal disease (p<0.0001) and if i.v. steroids (p=0.004) or immunosuppressants (p<0.0001) were used. 49.3% (558/1115) of patients required at least one intestinal surgery. More smokers had a 2nd surgical resection than patients who quit at, or before, the 1st resection and non-smokers (p=0.044: HR=1.39 95%CI 1.01-1.91). Patients smoking >3 cigarettes/day had an increased risk of developing B2/B3 disease (p=0.012: OR 3.8 95%CI 1.27-11.17).

CONCLUSION

Progression to B2/B3 disease and surgery is reduced by smoking cessation. All CD patients regardless of when they were diagnosed, or how many surgeries, should be strongly encouraged to cease smoking.

Outcomes of salvage therapy for steroid-refractory acute severe ulcerative colitis: ciclosporin vs. infliximab

BACKGROUND

Up to 40% of patients who present with acute severe ulcerative colitis (UC) fail to make an adequate response to intravenous corticosteroids. Ciclosporin or infliximab are currently employed as salvage therapy in this clinical scenario.

AIM

To compare clinical outcomes in patients treated with ciclosporin or infliximab in the setting of steroid-refractory acute severe UC.

METHODS

A prospective study of 83 consecutive presentations of steroid-refractory acute severe UC from 1999 to 2009 was conducted. All study participants satisfied the Truelove and Witts' criteria for acute severe UC. The primary outcome measures were rates of colectomy at discharge from hospital and at 3 months and 12 months following admission.

RESULTS

Eighty-three steroid-refractory acute severe UC events were generated by 83 patients. Salvage therapy was instituted with ciclosporin in 45 patients and infliximab in the remaining 38 patients. Of those patients who received ≥72 h of ciclosporin (2-4 mg/kg), 56% (24/43) avoided colectomy at the time of discharge, while this figure was 84% (32/38) for those administered one dose of infliximab (5 mg/kg) (P = 0.006). At 3 months, the colectomy-free rate was 53% for ciclosporin (23/43) vs. 76% for infliximab (28/37) (P = 0.04), and 42% (18/43) vs. 65% (24/37) at 12 months (P = 0.04). There were no deaths and two serious adverse events, both occurring in the ciclosporin group.

CONCLUSIONS

In this large cohort of patients presenting with acute severe UC, we have observed that infliximab salvage therapy is associated with lower rates of both severe adverse events and colectomy than ciclosporin in the short-term and medium-term.

Repression of microRNA-768-3p by MEK/ERK signalling contributes to enhanced mRNA translation in human melanoma

Increased global protein synthesis and selective translation of mRNAs encoding proteins contributing to malignancy is common in cancer cells. This is often associated with elevated expression of eukaryotic translation initiation factor 4 (eIF4E), the rate-limiting factor of cap-dependent translation initiation. We report here that in human melanoma downregulation of miR-768-3p as a result of activation of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway has an important role in the upregulation of eIF4E and enhancement in protein synthesis. Melanoma cells displayed increased nascent protein production and elevated eIF4E expression, which was associated with the downregulation of miR-768-3p that was predicted to target the 3'-untranslated region of the eIF4E mRNA. Overexpression of miR-768-3p led to the downregulation of the endogenous eIF4E protein, reduction in nascent protein synthesis and inhibition of cell survival and proliferation. These effects were efficiently reversed when eIF4E was co-overexpressed in melanoma cells. On the other hand, introduction of anti-miR-768-3p into melanocytes upregulated endogenous eIF4E protein expression and increased global protein synthesis. Downregulation of miR-768-3p appeared to be mediated by activation of the MEK/ERK pathway, in that treatment of BRAF(V600E) melanoma cells with the mutant BRAF inhibitor PLX4720 or exposure of either BRAF(V600E) or wild-type BRAF melanoma cells to the MEK inhibitor U0126 resulted in the upregulation of miR-768-3p and inhibition of nascent protein synthesis. This inhibition was partially blocked in cells cointroduced with anti-miR-768-3p. Significantly, miR-768-3p was similarly downregulated, which was inversely associated with the expression levels of eIF4E in fresh melanoma isolates. Taken together, these results identify downregulation of miR-768-3p and subsequent upregulation of eIF4E as an important mechanism in addition to phosphorylation of eIF4E responsible for MEK/ERK-mediated enhancement of protein synthesis in melanoma.

Serious infections in patients with inflammatory bowel disease receiving anti-tumor-necrosis-factor-alpha therapy: an Australian and New Zealand experience

BACKGROUND AND AIM

Anti-tumor-necrosis-factor-alpha (anti-TNF-α) medications are effective in inflammatory bowel disease (IBD), but have an increased risk of tuberculosis (TB) and serious infections. The aim of this study was to examine the Australian/New Zealand experience of serious infections and TB in IBD patients receiving anti-TNF-α therapy from 1999-2009.

METHODS

Serious infections, defined as 'requiring hospital admission' and TB cases in patients receiving, or within 3 months following, anti-TNF-α therapy were analyzed across Australia and New Zealand. Patient demographics, IBD medications, duration of anti-TNF-α therapy, and infection details were collected.

RESULTS

A total of 5562 IBD patients were managed across the centers. Of these, 489 (16.8%) Crohn's disease and 137 (5.2%) ulcerative colitis patients received anti-TNF-α therapy. There were three cases of latent TB that received prophylaxis prior to anti-TNF-α therapy. No cases of active TB were reported. Fourteen (2.2%) serious infections occurred. Seven occurred in patients receiving anti-TNF-α therapy for less than 6 months, including two cases of primary Varicella zoster (VZV), two cases of Pneumocystis jiroveci pneumonia, two cases of Staphylococcus aureus bacteremia, and one severe flu-like illness. Six patients were taking additional immunosuppressive medications. The other seven infections occurred after 6 months (mean 32.6 ± 24.3 months) and included one case of primary VZV, one flu-like illness, and five bacterial infections. All infections resolved with treatment.

CONCLUSION

TB is a very rare complication of anti-TNF-α therapy in Australia and New Zealand. Serious infections are uncommon but early opportunistic infections with Pneumocystis jiroveci pneumonia suggest a need for vigilance in patients on multiple immunosuppressive medications. VZV vaccination prior to immunosuppressive therapy should be considered in VZV-naïve patients.

Comparison of a Commercial Reversed Passive Latex Agglutination Assay to an Enzyme Immunoassay for the Detection of Shiga Toxin-Producing Escherichia coli

A multicenter study was performed to compare the performance of a prototypic reversed passive latex agglutination assay (VTEC Screen "Seiken"; Denka-Seiken, Japan) with the Premier EHEC Enzyme Immunoassay (Meridian Diagnostics, USA) for the detection of Shiga toxin in 554 diarrheal stool samples. Standard culture on sorbitol MacConkey agar and the use of latex agglutination reagents were included to identify the Escherichia coli O157, O26 and O111 serotypes. There was 99% agreement between the VTEC screen and enzyme immunoassay (kappa=0.823). Seventeen samples were positive for toxin by one or both assays. One toxin-positive sample using the enzyme immunoassay and four positive samples using the VTEC Screen could not be confirmed. Serotypes identified included: O157:H7 (n=8), O26 (n=2), O111 (n=1) and O45:H2 (n=1). The VTEC screen is easy to perform and comparable to the Meridian EHEC test for detection of Shiga toxin in clinical samples.

Rapid detection of Campylobacter jejuni in stool specimens by an enzyme immunoassay and surveillance for Campylobacter upsaliensis in the greater Salt Lake City area

The Alexon-Trend, Inc. (Ramsey, Minn.), ProSpecT Campylobacter microplate assay was compared with culture on a Campy-CVA plate (Remel, Lenexa, Kans.) and blood-free campylobacter agar with cefoperazone (20 microg/ml), amphotericin B (10 microg/ml), and teicoplanin (4 microg/ml) (CAT medium; Oxoid Limited, Hampshire, England) with 631 patient stool samples. The CAT medium was used to isolate Campylobacter upsaliensis. The enzyme immunoassay (EIA) had a sensitivity and a specificity of 89 and 99%, respectively, and the positive and negative predictive values were 80 and 99%, respectively. Even though we extensively looked for C. upsaliensis in stool samples from patients from the greater Salt Lake City area, we did not isolate this species during the study period. The overall excellent specificity of the EIA allows rapid detection and treatment of positive patients; however, a negative result should be confirmed by culture when clinical suspicion is high.

Extracts from "Clinical Evidence". Malaria: prevention in travellers

DEFINITION

Malaria is caused by a protozoan infection of red blood cells with one of four species of the genus plasmodium: P falciparum, P vivax, P ovale, or P malariae. Clinically, malaria may present in different ways, but it is usually characterised by fever (which may be swinging), tachycardia, rigors, and sweating. Anaemia, hepatosplenomegaly, cerebral involvement, renal failure, and shock may occur. INCIDENCE/PREVALENCE: Each year there are 300-500 million clinical cases of malaria. About 40% of the world's population is at risk of acquiring the disease. Each year 25-30 million people from non-tropical countries visit areas in which malaria is endemic, of whom between 10,000 and 30,000 contract malaria. AETIOLOGY/RISK FACTORS: Malaria is mainly a rural disease, requiring standing water nearby. It is transmitted by bites from infected female anopheline mosquitoes, mainly at dusk and during the night. In cities, mosquito bites are usually from female culicene mosquitoes, which are not vectors of malaria. Malaria is resurgent in most tropical countries and the risk to travellers is increasing.

PROGNOSIS

Ninety per cent of travellers who contract malaria do not become ill until after they return home. "Imported malaria" is easily treated if diagnosed promptly, and it follows a serious course in only about 12% of people. The most severe form of the disease is cerebral malaria, with a case fatality rate in adult travellers of 2-6%, mainly because of delays in diagnosis.

AIMS

To reduce the risk of infection; to prevent illness and death.

OUTCOMES

Rates of malarial illness and death, and adverse effects of treatment. Proxy measures include number of mosquito bites and number of mosquitoes in indoor areas. We found limited evidence linking number of mosquito bites and risk of malaria.

METHODS

Clinical Evidence search and appraisal in November 1999. We reviewed all identified systematic reviews and randomised controlled trials (RCTs).

The effect of tilmicosin administered to ewes prior to lambing on incidence of clinical mastitis and subsequent lamb performance

The effect of tilmicosin on the incidence of clinical mastitis and subsequent lamb performance was studied in 9 sheep flocks in Ontario. Ewes were treated randomly with either tilmicosin or placebo approximately one month prior to lambing. Outcome was assessed by comparing rates of clinical mastitis, palpable udder abnormalities, and preweaning (50-day) lamb weights between the 2 treatment groups, while controlling for other important variables. Lambs raised by multiparous ewes treated with tilmicosin were significantly heavier than lambs from placebo-treated multiparous ewes at 50 days. Lambs from tilmicosin-treated ewes were on average 0.52 kg heavier than lambs in the placebo group. There was no difference between treatment groups in the weight of lambs from first parity ewes. Tilmicosin treatment resulted in a 43% decrease in palpable udder abnormalities. Incidence of clinical mastitis did not differ between experimental groups. The administration of tilmicosin prelambing, at the time of routine clostridial disease vaccination, may be a beneficial and convenient way to reduce mastitis infection and improve the preweaning gain of lambs.

Mefloquine to prevent malaria: a systematic review of trials

OBJECTIVE

To evaluate the research evidence on the efficacy and tolerability of mefloquine chemoprophylaxis.

SEARCH STRATEGY

Any potentially relevant trial from the Cochrane Infectious Disease Group's register of controlled trials; systematic searches of Medline, Embase, Lilacs and Science Citation Index; scanning citations; and consulting drug companies and key investigators. We considered studies in all languages.

INCLUSION CRITERIA

Trials carried out in non-immune adult travellers, and in non-travelling volunteers, where an attempt had been made to conduct a randomised comparison of mefloquine against placebo or against alternative standard prophylaxis.

RESULTS

37 potentially eligible trials of mefloquine prophylaxis were identified, and 10 met the inclusion criteria. These 10 trials comprised a total of 2750 non-immune adult participants randomised to mefloquine or to a control. One placebo controlled trial examined malaria incidence directly and showed mefloquine to be highly effective in preventing malaria in an area of drug resistance. However, four placebo controlled trials showed that mefloquine was not well tolerated, and withdrawals were consistently higher in mefloquine treatment arms than in placebo arms (odds ratio 3.49 (95% confidence interval 1.42 to 8.56)). Five field trials compared mefloquine with other chemoprophylaxis. Mefloquine was no worse tolerated than other chemoprophylaxis, although there was possibly a trend towards higher withdrawals in mefloquine arms (odds ratio 1.33 (0.75 to 2.36)).

CONCLUSION

One trial showed mefloquine to be effective in preventing malaria, but withdrawal rates, presumably from side effects, were high across most studies. This is likely to impair mefloquine's effectiveness in general travellers, and it may therefore not be useful for routine prophylaxis. Mefloquine may be useful in specific situations such as for groups travelling to regions with a high risk of chloroquine resistant malaria and only limited access to effective medical care.

Dog bites in Bosnia

BACKGROUND

Rabies is a zoonosis that remains endemic in most parts of the world. Primary care physicians are in the first line of defence against the disease. An increasing number of British practitioners and medical students are being exposed to the dangers of rabies through humanitarian work on overseas attachments. Rabies is enzootic throughout Bosnia-Herzegovina and presents a hazard to the multinational troops currently deployed there.

AIM

To describe the British Army's experience of animal bites and rabies prevention in Bosnia during the first six months of its current peace enforcement mission, and to make general recommendations on the good management of any rabies hazard at primary care level and under field conditions.

METHODS

Routine data from the Army's epidemiological database (ARRC 97) were reviewed, and theatre issues of rabies vaccine and immune globulin were used as a proxy measure for administered post-exposure prophylaxis.

RESULTS

A total of 62 animal bites were reported in British troops between December 1995 and May 1996, of which 28 were unprovoked bites and resulted in the administration of a course of rabies vaccine. Ten of these were severe bites and rabies immune globulin (RIG) was administered in addition. The total cost of rabies post-exposure prophylaxis was US$6914.00.

CONCLUSION

The prevention of rabies has major human and resource implications, and primary care staff involved in rabies post-exposure management need to be well supported in their clinical decision-making. Rabies protocols should be clear and unambiguous. The effective medical surveillance of military or humanitarian missions in rabies-enzootic areas must include the prompt reporting of animal bites. The predeployment training of medical teams should include an up-to-date assessment of the local rabies threat.

A psychiatric patient classification system that works!

Having used a Patient Classification System for six years which had limited psychiatric indicators and data processed elsewhere at considerable delay, Alberta Hospital Ponoka implemented a new system which has met with great success. Generic workload indicators were developed by staff. These could be modified easily to meet various unit needs. Relatively accurate prediction of staffing needs greatly facilitates budgeting.

Evaluating the drug dependency unit

An evaluation of the St Mary's Drug Dependency Unit is described. Unit staff were interviewed and a retrospective analysis of 156 records was performed. The advent of HIV infection has led to an emphasis on public health priorities in the treatment of drug misuse. However, DDU staff retain a highly individualistic approach to their work. Staff aiming at abstinence within treatment may compromise important advice on harm minimization. The mean delay between first contact and entering treatment was 10 days; 42% of clients failed to complete the initial assessment. The need to extend access to the service is not easy to reconcile with the increasingly specialised support role for such units implied in recent strategy documents. Little is known of the effectiveness of different services for drug misusers. In this study, only 6% of clients were known to have achieved abstinence at one year. The efficiency of the DDU could be improved by closer definition of the unit's goals and target population, regular progress reviews, shortening the assessment procedure and the computerisation of data collection.