The natural history of a genetic subtype of arrhythmogenic right ventricular cardiomyopathy caused by a p.S358L mutation in TMEM43

To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility.     

Estimating global and regional morbidity from acute bacterial meningitis in children: assessment of the evidence

Aim

To estimate global morbidity from acute bacterial meningitis in children.

Methods

We conducted a systematic review of the PubMed and Scopus databases to identify both community-based and hospital registry-based studies that could be useful in estimation of the global morbidity from bacterial meningitis in children. We were primarily interested in the availability and quality of the information on incidence rates and case-fatality rates. We assessed the impact of the year of study, study design, study setting, the duration of study, and sample size on reported incidence values, and also any association between incidence and case-fatality rate. We also categorized the studies by 6 World Health Organization regions and analyzed the plausibility of estimates derived from the current evidence using median and inter-quartile range of the available reports in each region.

Results

We found 71 studies that met the inclusion criteria. The only two significant associations between the reported incidence and studied covariates were the negative correlation between the incidence and sample size (P < 0.001) and positive correlation between incidence and case-fatality rate (P < 0.001). The median incidence per 100 000 child-years was highest in the African region – 143.6 (interquartile range [IQR] 115.6-174.6), followed by Western Pacific region with 42.9 (12.4-83.4), the Eastern Mediterranean region with 34.3 (9.9-42.0), South East Asia with 26.8 (21.0-60.3), Europe with 20.8 (16.2-29.7), and American region with 16.6 (10.3-33.7). The median case-fatality rate was also highest in the African region (31.3%). Globally, the median incidence for all 71 studies was 34.0 (16.0-88.0) per 100 000 child-years, with a median case-fatality rate of 14.4% (5.3%-26.2%).

Conclusions

Our study showed that there was now sufficient evidence to generate improved and internally consistent estimates of the global burden of acute bacterial meningitis in children. Although some of our region-specific estimates are very uncertain due to scarcity of data from the corresponding regions, the estimates of morbidity and case-fatality from childhood bacterial meningitis derived from this study are consistent with mortality estimates derived from multi-cause mortality studies. Both lines of evidence imply that bacterial meningitis is a cause of 2% of all child deaths.Meningitis is an infectious disease affecting the brain membrane and spinal cord (1). Globally, bacterial meningitis is the most severe type of meningitis, mainly caused by a triad of species Neisseria meningitidis, Streptocccus pneumonia, and Haemophilus influenzae (2). While viral meningitis is usually a self-limiting disease with good prognosis, bacterial meningitis is potentially fatal, requiring urgent medical assistance and management with antibiotics treatment (3). Various estimates of the burden of bacterial meningitis have been proposed to date, but they have mainly focused on mortality (4), long-term sequels (5), or etiology-specific morbidity and mortality (6-8).Interestingly, there have been no comprehensive attempts to estimate the overall global burden of bacterial meningitis in children. This is not surprising, because such attempt would face almost insurmountable methodological challenges. First, there is a problem with case definition of “bacterial meningitis” (9). In low resource settings, where the problem is most common, many children may present with “purulent meningitis,” whose cause is highly likely bacterial, but laboratory capacity may not be sufficient to isolate the causal agent and confirm the diagnosis. This leads to a discrepancy between morbidity burden estimates based on “all purulent meningitis” and “laboratory confirmed meningitis” – the latter always being lower than the former, but to a different extent in different contexts (10). The second large methodological obstacle is the problem of “meningitis belt.” The meningitis belt is the band of countries extending from Senegal to Ethiopia, characterized by semi-arid climate, dry seasons, and dusty winds, with seasonal outbreaks of meningococcal meningitis being recorded since the beginning of the 20th century (11). The problem with these epidemics is that they can last for several years and dramatically change the importance of meningococcus in comparison to the other two bacterial agents (S. pneumoniae and H. influenzae) both regionally and globally (11). This makes it difficult to express the “burden of disease” for any given year, because it will be very different in intra-epidemic and inter-epidemic years. Moreover, the extent of vaccine coverage against N. meningitidis, S. pneumoniae and H. influenzae is changing the burden rapidly and rather dramatically in many places, rendering the scarce evidence from before the period of vaccination rather useless and indicates a need of revision (12). Finally, the emergence of HIV/AIDS pandemic led to a substantial number of infected children, whose resistance to other infections is impaired and they present a specific category of population in which the rates of incidence and case-fatality rates may be very different from those in other children (13).It is apparent that meningitis continues to contribute significantly to global mortality and morbidity, but the impact of the efforts to control it is difficult to estimate given that we do not have comprehensive estimates of global morbidity patterns. Understanding the global morbidity from bacterial meningitis would be useful because it would also help to validate the existing mortality estimates through application of appropriate case-fatality rates. The purpose of the present study is to provide a comprehensive assessment of the evidence that is available for estimating the global morbidity from acute bacterial meningitis in children globally. We will also propose initial, robust estimates of the burden, with suggestions on the possible ways to address the methodological challenges in future studies.     

Paediatric focal nodular hyperplasia: A case study of typical contrast-enhanced ultrasound findings with quantitative analysis and correlated with magnetic resonance imaging

IntroductionFocal nodular hyperplasia, a benign liver tumour, is the second most common focal benign liver lesion, after a cavernous haemangioma. Contrast-enhanced ultrasound is used increasingly for the diagnostic work up and follow-up of focal liver lesions in adults, but is particularly valuable in the paediatric population, with the ability to reduce radiation and the nephrotoxic contrast agents used in computed tomography or magnetic resonance imaging. Confident recognition of focal nodular hyperplasia is important; it is benign, usually asymptomatic, of no clinical significance, of no clinical consequence or malignant potential. We present a case of focal nodular hyperplasia of the liver with its characteristic findings on conventional ultrasound, contrast-enhanced ultrasound with quantitative analysis and correlated with magnetic resonance imaging.Case presentation: A 15-year-old female with right upper quadrant abdominal pain was referred for liver ultrasound. A focal liver lesion was detected on B-mode ultrasound examination, and colour Doppler demonstrated no specific features. Contrast-enhanced ultrasound examination demonstrated early arterial enhancement, with a characteristic spoke-wheel pattern, centrifugal uniform filling of the lesion on the late arterial phase and sustained enhancement on the portal venous phase. Quantitative contrast-enhanced ultrasound has been performed, showing a typical curve of enhancement, as well as characteristic parametric images, supporting the interpretation of contrast-enhanced ultrasound and assisting the diagnosis. Magnetic resonance imaging demonstrated a central T2 hyperintense scar and similar enhancement characteristics as contrast-enhanced ultrasound on T1 gadolinium-enhanced sequences.ConclusionContrast-enhanced ultrasound is a useful technique for the differentiation of benign from malignant liver lesions and has the potential to establish the diagnosis of focal nodular hyperplasia, based on the enhancement pattern, which is similar to that observed on magnetic resonance imaging but can be better appreciated with superior temporal, contrast and spatial resolution of contrast-enhanced ultrasound.     

Beneficial effects of insulin-like growth factor I on epithelial structure and function in parenterally fed rat jejunum

BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8)     

Is formal training necessary for capsule endoscopy?: The largest gastroenterology trainee study with controls

BACKGROUND: Little is known about the infrastructure to train gastroenterologists in capsule endoscopy. The level of capsule endoscopy exposure among trainees in the United Kingdom or Europe has also not been quantified. AIMS AND METHODS: To assess the ability of 10 gastroenterology trainees with endoscopy experience to interpret 10 capsule endoscopy videos against five medical students, with an expert in capsule endoscopy as the gold standard. Parameters assessed included gastric emptying time, small bowel transit and the diagnosis made. A questionnaire survey assessed the level of capsule endoscopy exposure among United Kingdom trainees. RESULTS: Trainees were better at determining the gastric emptying time (p=0.013) and more likely to record true positives compared to the students (p=0.037). They were also less likely to record false positives (p=0.005) and more likely to reach the correct diagnosis (p=0.001, OR 3.6, CI 1.8-7.4). Our survey found that, 65% of trainees had prior exposure to capsule endoscopy but only 13% had done capsule endoscopy reporting. Sixty seven percent felt capsule endoscopy should be incorporated into their training. CONCLUSION: This study has shown that prior endoscopic experience enables trainees to interpret capsule endoscopy more accurately than medical students. However, there is a demand for focussed training which would enable trainees to reliably interpret pathology on capsule endoscopy.