Impact of transition from microscopy to molecular screening for detection of intestinal protozoa in Dutch patients

Detection of intestinal protozoa by PCR methods has been described as being sensitive and specific, and as improving the diagnostic yield. Here we present the outcome of the transition from microscopy to molecular screening for detection of a select group of intestinal protozoa in faeces in our laboratory. Introduction of molecular screening for intestinal protozoa resulted in higher sensitivity, reduced hands-on-time, reduced time-to-results, leading to improved diagnostic efficiency.     

全国细菌耐药监测网2014-2019年粪便标本细菌耐药监测报告

目的 了解全国粪便标本分离病原菌的菌群分布及耐药情况.方法 从2014-2019年全国细菌耐药监测网报告中提取粪便标本的相关数据(去除肠道正常定植菌群),分析肠道致病菌及其耐药率的变迁.结果 共分离菌株61 809株,居前3位的是沙门菌属(82.12％)、志贺菌属(8.08％)、弧菌属(4.03％),沙门菌属在每年粪便...     

A case report of cutaneous larva migrans in Argentina

Cutaneous larva migrans (CLM) represents the most common tropically acquired dermatosis. CLM is caused by infection with hookworm larvae in tropical and sub-tropical areas, and people who have a history of foreign travel and of walking barefoot on sandy soil or beaches are at a high risk of getting infected with it. The diagnosis is usually made on the basis of the typical appearance of the lesion, intense itching and history of foreign travel. CLM is a common parasitic skin disease that can be easily prevented by wearing ‘protective’ footwear. A case of CLM is described in this article.     

Technical report: results of immunological tests on faecal extracts are likely to be extremely misleading.

Clinical investigation of gut immunity is difficult because of the need to study intestinal tissues or secretions directly. Others have reported that immunoglobulins, antibodies and cytokines can be detected in saline extracts of faeces. We have assessed the validity of this approach by measuring immunoglobulins, albumin, alpha 1-antitrypsin and isotype-specific antibodies in matched samples of faeces and whole gut lavage fluid. Results were compared as estimated output per day, and by using haemoglobin as a common reference substance. Samples were obtained from 10 patients with active inflammatory bowel disease and 10 with other benign GI diseases. For immunoglobulins, albumin and antibodies, the amount detected in faeces varied from < 0.01% to 35.5% (based on estimated daily output) and < 0.01% to 18.5% (based on haemoglobin) of the amount known to be produced in the gut from results of assays on whole gut lavage fluid (WGLF); there were significantly higher rates of recovery in faecal specimens from patients with active gut inflammation than from other patients. Detection rates and titres of specific antibody in faeces were even lower than those for immunoreactive IgA. These data indicate that immunological tests on saline extracts of faeces do not represent the true status of the gut humoral immune system, and such studies should be strongly discouraged.     

Seeking clues for a positive diagnosis of the irritable bowel syndrome

Abstract. Despite its high prevalence the irritable bowel syndrome (IBS) lacks acceptable pathophysio-logical markers and its diagnosis largely depends on the exclusion of underlying organic disease. Systemic acid-base balance, serum electrolytes and the composition of faecal water (electrolytes and organic anions), were studied in thirty-eight diarrhoeal patients out of a series of ninety-three consecutive IBS patients. Only patients with diarrhoea as the predominant symptom were included in the study to evaluate whether this subgroup could provide the clue for a positive diagnosis of the syndrome. Serum electrolytes and systemic acid–base balance were within the normal range. Faecal electrolytes were also normal (Na 26·6 pL 19·3 SD; K 66·8 pL 28·3; Cl 19·1 pL 15·2 mEq l^-1), despite the finding of a moderately increased 24-h faecal output. The K: Na ratio was also within the normal range. These data are in agreement with the lack of systemic changes observed in IBS patients even with profuse or longstanding diarrhoea. Both faecal short chain fatty acids and lactic acid were increased in patients vs. controls, but a considerable overlap with normal values was observed (131·4 pL 62·6 SD vs. 108·5 pL 58·3 mEq l^-1). Only lactic acid concentration was significantly higher than in controls (1·3 pL 1·2 vs. 0·5 pL 0·2). Despite these findings it is concluded that the subgroup of IBS patients with diarrhoea also appears to lack a pathophysiological marker and does not provide clues for a positive diagnosis of this syndrome.     

Complaints about dog faeces as a symbolic representation of incivility in London,UK: a qualitative study

During a ‘Well London’ study, residents were asked about their neighbourhood and its environment. Above all other complaints, ‘dog poo’ was mentioned as a key concern. Despite low rates of infection and disease among the human population resulting from contact with canine faecal matter, the concerns of the public continue to rate it as a serious public health issue. Most public health studies, therefore, seek to identify processes of transmission and disease pathology as a method of addressing the problem. This study approaches the issue through a contextualised analysis of residents’ complaints, using anthropological theory to examine the symbolic representation of ‘dog poo’. Analysis of the interviews shows that these specific complaints were located among less easily defined or articulated experiences of social and environmental neglect, where neighbours were estranged from one another and local authorities seen as negligent. This approach has important implications for public health, as it provides not only a strong indicator of the level of dissatisfaction within some of London's more disadvantaged neighbourhoods, but also identifies a need for policies that are grounded in cross-disciplinary research into the relationship between health, ‘wellbeing’ and experiences of marginalisation among urban populations.     

Diagnosis of hepatitis A infection: Comparative specificity of IgM capture assays using antigens derived from tissue cultures and marmoset faeces

Hepatitis A virus (HAV) antigens from two tissue culture sources were compared with that from the faeces of infected marmosets to determine whether the former were satisfactory substitutes. Sera from 313 healthy blood donors and 417 patients with various clinical conditions were tested for IgM class antibody to HAV (anti-HAV IgM) using an IgM antibody capture assay (MACRIA) with each of the 3 antigens.Forty-eight specimens, all from cases of acute hepatitis, were positive in MACRIA with all 3 antigens. Only 2 of the 313 blood donors' sera reacted at all. These reactions were weak and did not arise with all antigens. Weakly reactive specimens were also found in 3 out of the 13 clinical categories. Overall 12 weak reactions arose with the faecal antigen and 8 and 7 with the two tissue culture antigens. Rheumatoid factor (RhF) was detected in 8 of the weakly reactive specimens and these had significantly higher titres of anti-HAV than sera known to contain RhF that were unreactive in MACRIA.It is concluded that tissue culture derived HAV antigen should replace that from primates on the grounds of quality, economy and convenience: also that non-specific activity in HAV MACRIA is usually due to a combination of RhF and high anti-HAV titres, but is infrequently strong enough to cause reactions interpreted as positive.     

Epigenetically silenced miR-34b/c as a novel faecal-based screening marker for colorectal cancer

Background:

MicroRNAs are tiny non-coding small endogenous RNAs that regulate gene expression by translational repression, mRNA cleavage and mRNA inhibition. The aim of this study was to investigate the hypermethylation of miR-34b/c and miR-148a in colorectal cancer, and correlate this data to clinicopathological features. We also aimed to evaluate the hypermethylation of miR-34b/c in faeces specimens as a novel non-invasive faecal-DNA-based screening marker.

Methods:

The 5-aza-2′-deoxycytidine treatment and methylation-specific PCR were carried out to detect the hypermethylation of miR-34b/c and miR-148a.

Results:

The miR-34b/c hypermethylation was found in 97.5% (79 out of 82) of primary colorectal tumours, P=0.0110. In 75% (21 out of 28) of faecal specimens we found a hypermethylation of miR-34b/c while only in 16% (2 out of 12) of high-grade dysplasia. In addition, miR-148a was found to be hypermethylated in 65% (51 out of 78) of colorectal tumour tissues with no significant correlation to clinicopathological features. However, a trend with female gender and advanced age was found, P=0.083. We also observed a trend to lower survival rate in patients with miR-148a hypermethylation with 10-year survival probability: 48 vs 65%, P=0.561.

Conclusions:

These findings show that aberrant hypermethylation of miR-34b/c could be an ideal class of early screening marker, whereas miR-148a could serve as a disease progression follow-up marker.     

荧光凝胶色谱法测定大鼠单次口服麦冬多糖MDG-1排泄变化

目的:探讨单次口服麦冬多糖MDG-1后排泄量的变化.方法:采用异硫氰酸荧光素(FITC)对麦冬多糖MDG-1进行标记( F-MDG-1),测定取代度.采用高效凝胶色谱法(HPGPC)对粪便及尿液内MDG-1含量进行测定.SD-雄性大鼠,给药组按照300 mg· kg-给予F-MDG-1,空白组给予纯水,分别在0,4,12,24,48,72 h收集尿液及粪便.测定含量.结果:在单次给予F-MDG-1量300 mg· kg-1后,尿液中含量测定在12 h时达到最大排泄量0.808 7 mg,而后逐渐减少,至72 h最低0.105 3 mg;在粪便测定中在12h达到最大排泄量为21.332 4 mg,而后逐渐减少,至72 h最低0.506 5 mg.结论:采用FITC对MDG-1进行标记,并采用荧光色谱法对MDG-1在排泄物内的含量变化进行研究是可行的.MDG-1基本不被人体吸收,其主要经粪便排泄.     

Clinical importance of faecal calprotectin variability in inflammatory bowel disease: intra-individual variability and standardisation of sampling procedure

Objective Faecal (f-) calprotectin is a biomarker of intestinal inflammation. Previous studies have described intra-individual day-to-day variability of this biomarker in patients with inflammatory bowel disease (IBD) and morning samples have been suggested for standardisation purposes. With this project, we investigated if day-to-day variability differed from diurnal variability. Additionally, we evaluated a new extraction method for f-calprotectin analysis. Methods Fifty patients provided three faeces samples from morning – evening – morning on two consecutive days. Nineteen patients provided two faeces samples from the same bowel movement, one conventional spot sample, and one sample with a device for patient-administered sampling and extraction. Results The two morning samples differentiated between mucosal inflammation and mucosal healing with same level of agreement as the two samples from the same day (kappa 0.76), using an f-calprotectin cut-off level of 259?μg/g. Although large intra-individual variation in f-calprotectin values, there were no significant day-to-day (p?=?0.096) or diurnal variation (p?=?0.78). Used by laboratory technicians, the new extraction device correlated significantly with the conventional extraction method (p?Conclusions The reliability of f-calprotectin morning samples is equal to the reliability of samples from different bowel movements on the same day. The new extraction method is reliable when used by laboratory technicians, but larger studies are recommended to evaluate patient administered extraction.