Multicenter experience from the UK and Ireland of use of lumen-apposing metal stent for transluminal drainage of pancreatic fluid collections

BACKGROUND AND STUDY AIMS

 Pancreatic fluid collection (PFC) is a common complication of pancreatitis for which endoscopic ultrasound-guided drainage is first-line treatment. A new single-device, lumen-apposing, covered self-expanding metal stent (LAMS) has been licensed for PFC drainage. We therefore present our multicenter experience with the LAMS for PFC drainage in a multicenter prospective case series to assess success and complication rates.

PATIENTS AND METHODS

 All adult patients from 11 tertiary centers who had LAMS placement for PFC from July 2015 to July 2016 were included. Data including indications, technical success, clinical success, collection resolution, stent removal, early and late adverse events (AEs), mortality and recurrence at 6 months were collected.

RESULTS

 116 patients, median age 52.5 years (range 16 - 80) and 67 % male, were treated with a single LAMS in each case. The indication was walled off necrosis (WON) in 70 and pseudocyst in 46. Median size of the PFC was 11 cm (5 - 21 cm) and the estimated median necrotic volume in WON was 30 % (5 % - 90 %). Stent insertion was technically successful in 115 (99.1 %) and clinically successful in 109 (94 %). Early serious AEs (SAEs): n = 7 sepsis, n = 1 stent blockage with food, n = 1 stent migration requiring laparotomy, n = 1 stent dislodgement and n = 1 bleeding requiring emboliZation. Late AEs: n = 1 buried stent and n = 1 esophageal fistula. Non-procedure-related deaths: n = 3 (2.5 %).

CONCLUSION

 This multicenter case series demonstrates that use of the new LAMS is feasible, effective and relatively safe in draining PFC with a technical success rate of 99 % and cumulative SAE rate of 11.2 %.

Swine as models in biomedical research and toxicology testing

Swine are considered to be one of the major animal species used in translational research, surgical models, and procedural training and are increasingly being used as an alternative to the dog or monkey as the choice of nonrodent species in preclinical toxicologic testing of pharmaceuticals. There are unique advantages to the use of swine in this setting given that they share with humans similar anatomic and physiologic characteristics involving the cardiovascular, urinary, integumentary, and digestive systems. However, the investigator needs to be familiar with important anatomic, histopathologic, and clinicopathologic features of the laboratory pig and minipig in order to put background lesions or xenobiotically induced toxicologic changes in their proper perspective and also needs to consider specific anatomic differences when using the pig as a surgical model. Ethical considerations, as well as the existence of significant amounts of background data, from a regulatory perspective, provide further support for the use of this species in experimental or pharmaceutical research studies. It is likely that pigs and minipigs will become an increasingly important animal model for research and pharmaceutical development applications.

Gastric amyloidosis presenting with severe weight loss

A previously well 59-year-old lady with 70 kg weight loss and chronic diarrhoea over a 28-month period presented following collapse and subsequent diagnosis of pulmonary embolism. Previous investigations for this weight loss included normal gastroscopy and colonoscopy, CT and MRI abdomen, barium follow through and octreotide scan. She underwent echocardiogram which revealed myocardial speckling and asymmetrical left ventricular hypertrophy. Repeat oesophago-gastro-duodenoscopy and colonoscopy for rectal bleeding was performed. Colonoscopy revealed intramucosal haematomas and electron microscopy (EM) of the gastric biopsies confirmed amyloid deposition. Amyloidosis of the gastrointestinal (GI) tract and heart were confirmed on serum amyloid protein scan. GI amyloid is rare and symptoms include weight loss, diarrhoea, GI bleeding and gut dysmotility.1 GI amyloidosis should be considered as a diagnosis and sought when other common causes have been excluded. The greatest yield is by Congo red staining or EM of rectal specimens.

Microfluidic platform for single nucleotide polymorphism genotyping of the thiopurine S-methyltransferase gene to evaluate risk for adverse drug events

Prospective clinical pharmacogenetic testing of the thiopurine S-methyltransferase gene remains to be realized despite the large body of evidence demonstrating clinical benefit for the patient and cost effectiveness for health care systems. We describe an entirely microchip-based method to genotype for common single nucleotide polymorphisms in the thiopurine S-methyltransferase gene that lead to serious adverse drug reactions for patients undergoing thiopurine therapy. Restriction fragment length polymorphism and allele-specific polymerase chain reaction have been adapted to a microfluidic chip-based polymerase chain reaction and capillary electrophoresis platform to genotype the common *2, *3A, and *3C functional alleles. In total, 80 patients being treated with thiopurines were genotyped, with 100% concordance between microchip and conventional methods. This is the first report of single nucleotide polymorphism detection using portable instrumentation and represents a significant step toward miniaturized for personalized treatment and automated point-of-care testing.

Can we use mid upper arm anthropometry to detect malnutrition in medical inpatients? A validation study

BACKGROUND AND AIMS

Mid upper arm anthropometry (MUAA) is often used as a measure of nutritional status to detect changes in body composition. The aim of this study was to investigate the reliability and validity of MUAA including mid arm circumference (MAC) and triceps skin fold thickness (TSFT) to determine the usefulness in clinical practice.

METHOD

We measured MUAA in 158 consecutive admissions along with subjective global assessment (SGA) and body mass index (BMI). Inter- and intra-rater reliability was evaluated in an additional 50 patients.

RESULTS

The sensitivity and specificity of MUAA <5th percentile was compared with SGA and BMI. MAC and TSFT had a low sensitivity and a high specificity with low positive predictive values when compared with criterion values which were BMI </=18 and SGA-C. The intra-class correlation coefficient for inter- and intra-rater reliability for MAC were 0.98 (95% CI 0.96-0.98) and 0.99 (95% CI 0.98-0.99) respectively and for TSFT were 0.97 (95% CI 0.91-0.97) and 0.98 (95% CI 0.95-0.98) respectively.

CONCLUSION

MUAA <5th percentile had a high specificity but low sensitivity when compared with indicators of malnutrition. Although MUAA could be reliably measured, it has poor validity and is thus unlikely to be a good predictor of clinical outcome. Percentiles based on healthy populations do not generalize well to the individuals seen in clinical practice.

Propofol intravenous conscious sedation for anxious children in a specialist paediatric dentistry unit

OBJECTIVES

To report on both the use and dosage of propofol, as a new intravenous (IV) conscious sedative agent, for anxious children referred to a specialist paediatric dentistry service.

SETTING

Paediatric Dentistry Unit, Glasgow Dental Hospital and School.

SAMPLE

Thirty-four children, 25 females and 9 males, mean age 12 years 10 months, with a mean weight of 54.6 kg (range 30-110 kg).

METHODS

Report from 34 patients receiving intravenous sedation for the first time in respect of weight dose and amount of treatment completed.

RESULTS

Thirty-two children successfully accepted operative dental care on their first visit, they received a mean total dose of 146.25 mg of propofol (range 10 mg to 356 mg); in relation to body weight, the mean was 2.5 mg/kg (range 0.2-5.4 mg/kg). The treatment that they received included fissure sealants, amalgam and adhesive restorations, root canal therapy and single and multiple extractions. Their sedation and recovery were uneventful.

CONCLUSIONS

Sub-anaesthetic doses of propofol used for IV conscious sedation infusion facilitated operative dental treatment in anxious children.

Ethnic differences in peripheral vascular disease

The wide variation in the way coronary artery disease (CAD) affects different ethnic groups and the associated risk factor profiles of these groups have been extensively studied, but ethnic differences in the clinical manifestations of peripheral vascular disease (PVD) have been relatively neglected. The aim of the present review is to provide an overview of PVD in different ethnic groups and to explore possible pathophysiological factors accounting for these differences. Atherosclerotic PVD is generally less prevalent in Indo-Asians and Afro-Caribbeans than in caucasians, despite the 'classical' risk factors being as prevalent, if not more so, suggesting the possibility of as yet unidentified risk factors in these groups. Angiographic and microscopic evidence suggests that patients of African or Afro-Caribbean origin suffer from a different pattern of PVD, which primarily affects the distal arteries. In contrast, Indo-Asians tend to suffer from thromboangiitis obliterans (Buerger's disease) far more frequently than other ethnic groups; thus, their arterial disease appears to present much earlier and with greater severity. However, if this sub-category of patient is excluded, they seem to suffer much less from 'simple' atherosclerotic disease than their caucasian counterparts. Despite a higher prevalence of diabetes among Indo-Asians, the prevalence of intermittent claudication is considerably less in this ethnic group.

Peripheral vascular disease and hypertension: a forgotten association?

Peripheral vascular disease (PVD) is associated with a high cardiovascular morbidity and mortality. Intermittent claudication is the most common symptomatic manifestation of PVD, but is also an important predictor of cardiovascular death, increasing it by three-fold, and increasing all-cause mortality by two to five-fold. Hypertension is a common and important risk factor for vascular disorders, including PVD. Of hypertensives at presentation, about 2-5% have intermittent claudication, with this prevalence increasing with age. Similarly, 35-55% of patients with PVD at presentation also have hypertension. Patients who suffer from hypertension with PVD have a greatly increased risk of myocardial infarction and stroke. Apart from the epidemiological associations, hypertension contributes to the pathogenesis of atherosclerosis, the basic underlying pathological process underlying PVD. Hypertension, in common with PVD, is associated with abnormalities of haemostasis and lipids, leading to an increased atherothrombotic state. Nevertheless, none of the large antihypertensive treatment trials have adequately addressed whether a reduction in blood pressure causes a decrease in PVD incidence. There is therefore an obvious need for such outcome studies, especially since the two conditions are commonly encountered together.

Paracetamol hepatotoxicity and alcohol consumption in deliberate and accidental overdose

We studied the relationship between alcohol consumption and hepatotoxicity related to paracetamol ingestion both in cases of overdose with suicidal intent and in cases where paracetamol was apparently taken for therapeutic reasons. In a retrospective study of 553 patients admitted to a specialist liver unit between January 1987 and December 1993 with paracetamol-induced hepatotoxicity, there was no difference in the severity of the hepatotoxicity following either a deliberate or an inadvertent overdose. Heavy alcohol consumption was more common in males than females and more commonly associated with deliberate overdoses of >15 g. There was no correlation between alcohol consumption and severity of hepatotoxicity (mean INR and the serum creatinine levels over the first 7 days after the overdose). The significantly lower platelet count in heavy drinkers was probably the consequence of direct alcohol toxicity to the marrow. Overall there was a greater incidence of heavy alcohol consumption amongst therapeutic misadventure compared to deliberate overdose cases, but there was no difference between the two groups when amounts of <10 g/day were involved. Eleven (29%) patients in the therapeutic misadventure group were depressed, 10 of whom had previously attempted suicide. In conclusion, we were unable to demonstrate that heavy drinkers develop more severe hepatotoxicity following paracetamol overdose than non-drinkers, and from the material reported in this study, accidental overdose is a better defining term than therapeutic misadventure.

Toxicologic evaluations of an immunotoxin, H65-RTA

A series of acute and multiple dose toxicology studies were performed to support the clinical dose and to evaluate the systemic toxicity of an immunotoxin, H65-RTA. H65-RTA consists of a murine anti-CD5 monoclonal antibody and ricin A chain (RTA). The LD50 of H65-RTA was estimated to be between 60 and 62.5 mg/kg in the rat. H65-RTA was administered to the rat and the monkey as a bolus injection at doses of 0.1, 0.5, and 2 mg/kg and over 1-hr infusion at 0.2 and 2 mg/kg, respectively. Two to three weeks of postdosing recovery was included in the study design. Following repeated doses of H65-RTA, the following findings were demonstrated: peripheral edema, decreased body weight, decreased body temperature (monkey only) in addition to a general inflammatory reaction evidenced by changes in hematology, clinical chemistry, and urinalysis parameters. Histopathologically, chronic inflammation in the nonarticular soft tissue was found in the rat at doses of 0.1 mg/kg and higher and monkeys developed much more severe toxicity when compared to the rat at the same doses. Inflammation, hemorrhage, and/or edema were evident in a variety of tissues. Myeloid hyperplasia was also evident. Additional findings resulting from the drug-related stress involved adrenals, spleen, thymus, and lymph nodes. All toxicity was reversible. The antibody response was evident in rats at doses of 0.5 mg/kg and higher and in all monkeys at doses of 0.2 and 2 mg/kg. In conclusion, since H65 antibody does not cross-react with the T cells from either the rat or the cynomolgus monkey, the toxicity observed in the studies described above was not related to T lymphocytes and was probably due to a series of acute to subacute inflammatory reactions caused largely by the RTA moiety of H65-RTA.

The current management of paracetamol overdosage

Paracetamol overdosage is a common problem, but severe poisoning occurs in only a small percentage of cases. A patient who has suffered paracetamol overdosage should be monitored carefully to ensure that a specialist liver unit can be contacted at the earliest signs of severe poisoning for optimal management and transfer. Paracetamol overdosage remains the most common cause of fulminant hepatic failure in the UK, with a mortality rate of 90%, but survival rates can be improved dramatically by specialist intensive care management, and with the advent of transplantation a previously untreatable group of patients can be treated successfully. However, a patient who is inadequately monitored and treated in the early stages after an overdose may deteriorate to an extent that renders them unsalvable by the time they arrive at the specialist centre.