Long-term esophageal cancer risk in patients with primary achalasia: a prospective study

OBJECTIVES

Achalasia patients are considered at increased risk for esophageal cancer, but the reported relative risks vary. Identification of this risk is relevant for patient management. We performed a prospective evaluation of the esophageal cancer risk in a large cohort of achalasia patients with long-term follow-up.

METHODS

Between 1975 and 2006, all patients diagnosed with primary achalasia in our hospital were treated and followed by the same protocol. After graded pneumatic dilatation, all patients were offered a fixed surveillance protocol including gastrointestinal endoscopy with esophageal biopsy sampling.

RESULTS

We surveyed a cohort of 448 achalasia patients (218 men, mean age 51 years at diagnosis, range 4-92 years) for a mean follow-up of 9.6 years (range 0.1-32). Overall, 15 (3.3%) patients (10 men) developed esophageal cancer (annual incidence 0.34 (95% confidence interval 0.20-0.56)). The mean age at cancer diagnosis was 71 years (range 36-90) after a mean of 11 years (range 2-23) following initial presentation, and a mean of 24 years (range 10-43) after symptom onset. The relative hazard rate of esophageal cancer was 28 (confidence interval 17-46) compared with an age- and sex-identical population in the same timeframe. Five patients received a potential curative treatment.

CONCLUSIONS

Although the gastro-esophageal cancer risk in patients with longstanding achalasia is much higher than in the general population, the absolute risk is rather low. Despite structured endoscopical surveillance, most neoplastic lesions remain undetected until an advanced stage. Efforts should be made to identify high-risk groups and develop adequate surveillance strategies.

Percutaneous endoscopic gastrostomy: complications and suggestions to avoid them

OBJECTIVES

Percutaneous endoscopic gastrostomy (PEG) tubes have become an excellent alternative for the long-term management of patients with proximal obstructions of the gastrointestinal tract. However, their use has limitations and can be associated with serious complications. We therefore studied the frequency and severity of complications related to the use of PEG tubes in our clinic.

DESIGN

All adults (aged 18 years and above) in whom a PEG tube was placed between January 1 1994 and January 1 1999 at the Free University Hospital in Amsterdam were included in this study. In initial cases, the indication and procedure were individually judged according to a liberal protocol. However, after several major complications, a strict procedure protocol was implemented in September 1996.

RESULTS

During the study period, 263 PEG tubes were placed in 254 patients with head and neck cancer (n = 183; 70%), neurological disorders (n = 52; 20%) or severe upper gastrointestinal motility disorders (n = 28; 11%). In period I, 167 PEG tubes were placed and in period II, 96 PEG tubes were inserted. Patients were followed for a median 111 days. Minor complications occurred in 13% of the patients. Major complications occurred in 8% of the patients. In period I, the percentage of major complications was higher than in period II (9.5% versus 6%).

CONCLUSION

PEG tube placement is a safe procedure when performed according to strict guidelines. By doing so, PEG tubes allow optimal feeding for prolonged periods with the occasional need for replacement of the tube. PEG tubes should not be introduced in acutely ill patients, patients with a short life expectancy and preferably not to patients with severe coughing.

Influence of salazosulphapyridine and 5-aminosalicylic acid on seminal qualities and male sex hormones

Seminal abnormalities are a common side effect of salazosulphapyridine (SASP) treatment. We evaluated semen qualities and sex hormone concentrations in 11 patients with inflammatory bowel disease (IBD) during SASP treatment and 4 months after replacing SASP with an oral slow-release preparation of 5-aminosalicylic acid (5-ASA). Significant improvement in sperm count (p less than 0.01), morphology (p less than 0.02), and motility (p less than 0.02) could be observed during 5-ASA therapy, in comparison with SASP treatment. Three pregnancies occurred during the study period. The serum concentrations of gonadotrophins, prolactin, and sex hormone-binding globulin were normal in all patients and not significantly different in the two treatment periods. The mean total testosterone concentration decreased significantly (p less than 0.02) after 5-ASA substitution, together with serum albumin (p less than 0.005), although all values remained within normal limits. The apparent free testosterone concentration was not significantly different in the two treatment periods. It is concluded that a significant improvement in semen quality can be obtained in male patients with IBD after replacing SASP with 5-ASA.

Oesophagitis is common in patients with achalasia after pneumatic dilatation

BACKGROUND

Achalasia, an oesophageal motor disease, is associated with functional oesophageal obstruction. Food stasis can predispose for oesophagitis. Treatment aims at lowering of the lower oesophageal sphincter pressure, enhancing the risk of gastro-oesophageal reflux. Nevertheless, the incidence of oesophagitis after achalasia treatment is unknown.

AIM

To investigate the incidence and severity of oesophagitis in achalasia patients treated with pneumatic dilatation.

METHODS

A cohort of 331 patients with achalasia were treated with pneumatic dilatation and followed. Oesophagitis and stasis were assessed by endoscopy and inflammation was graded by histology.

RESULTS

251 patients were followed for a mean values of 8.4 years (range: 1-26). The average number of endoscopies with biopsy sample sets per patient was 4 (range: 1-17). Three patients had no histological signs of oesophagitis throughout follow-up, 139 had oesophagitis grade 1, 49 oesophagitis grade 2 and 60 grade 3. Specialized intestinal metaplasia was found in 37 patients. The association between endoscopic food stasis and histological inflammation was significant. The association between endoscopic signs of oesophagitis and histological inflammation was poor.

CONCLUSIONS

Forty percent of the achalasia patients develop chronic active or ulcerating oesophagitis after treatment. Inflammation was associated with food stasis. Because the sensitivity of endoscopy to detect inflammation is low, surveillance endoscopy with biopsy sampling and assessment of stasis is warranted to detect early neoplastic changes.

A deep learning system for detection of early Barrett's neoplasia: a model development and validation study

BACKGROUND

Computer-aided detection (CADe) systems could assist endoscopists in detecting early neoplasia in Barrett's oesophagus, which could be difficult to detect in endoscopic images. The aim of this study was to develop, test, and benchmark a CADe system for early neoplasia in Barrett's oesophagus.

METHODS

The CADe system was first pretrained with ImageNet followed by domain-specific pretraining with GastroNet. We trained the CADe system on a dataset of 14 046 images (2506 patients) of confirmed Barrett's oesophagus neoplasia and non-dysplastic Barrett's oesophagus from 15 centres. Neoplasia was delineated by 14 Barrett's oesophagus experts for all datasets. We tested the performance of the CADe system on two independent test sets. The all-comers test set comprised 327 (73 patients) non-dysplastic Barrett's oesophagus images, 82 (46 patients) neoplastic images, 180 (66 of the same patients) non-dysplastic Barrett's oesophagus videos, and 71 (45 of the same patients) neoplastic videos. The benchmarking test set comprised 100 (50 patients) neoplastic images, 300 (125 patients) non-dysplastic images, 47 (47 of the same patients) neoplastic videos, and 141 (82 of the same patients) non-dysplastic videos, and was enriched with subtle neoplasia cases. The benchmarking test set was evaluated by 112 endoscopists from six countries (first without CADe and, after 6 weeks, with CADe) and by 28 external international Barrett's oesophagus experts. The primary outcome was the sensitivity of Barrett's neoplasia detection by general endoscopists without CADe assistance versus with CADe assistance on the benchmarking test set. We compared sensitivity using a mixed-effects logistic regression model with conditional odds ratios (ORs; likelihood profile 95% CIs).

FINDINGS

Sensitivity for neoplasia detection among endoscopists increased from 74% to 88% with CADe assistance (OR 2·04; 95% CI 1·73-2·42; p<0·0001 for images and from 67% to 79% [2·35; 1·90-2·94; p<0·0001] for video) without compromising specificity (from 89% to 90% [1·07; 0·96-1·19; p=0·20] for images and from 96% to 94% [0·94; 0·79-1·11; ] for video; p=0·46). In the all-comers test set, CADe detected neoplastic lesions in 95% (88-98) of images and 97% (90-99) of videos. In the benchmarking test set, the CADe system was superior to endoscopists in detecting neoplasia (90% vs 74% [OR 3·75; 95% CI 1·93-8·05; p=0·0002] for images and 91% vs 67% [11·68; 3·85-47·53; p<0·0001] for video) and non-inferior to Barrett's oesophagus experts (90% vs 87% [OR 1·74; 95% CI 0·83-3·65] for images and 91% vs 86% [2·94; 0·99-11·40] for video).

INTERPRETATION

CADe outperformed endoscopists in detecting Barrett's oesophagus neoplasia and, when used as an assistive tool, it improved their detection rate. CADe detected virtually all neoplasia in a test set of consecutive cases.

FUNDING

Olympus.

Activation of human B cells: involvement of surface immunoglobulin as evidenced by two biochemically distinct types of response to Staphylococcus aureus

If activation of human B cells by Staphylococcus aureus proceeds through interaction of surface immunoglobulin with Staphylococcal protein A, then immunoglobulins should be produced that are capable of binding to protein A as a consequence of such stimulation. In the present report it is shown that two biochemically distinct types of response to S. aureus are demonstrable in human peripheral blood lymphocytes. Two types of IgM are produced: IgM capable of binding to protein A, and IgM that does not bind and can be recovered by immunoprecipitation with anti-Ig antibodies. Cloned cell lines produce one of either type of Ig, but not both. Therefore, interaction of protein A with Ig alone cannot account for the stimulatory properties of S. aureus. When S. aureus is used in conjunction with pokeweek mitogen, a synergistic effect between the two mitogens is seen. Under conditions of optimal synergistic stimulation, the increase in immunoglobulin production is seen virtually exclusively in the category of molecules capable of binding to protein A. These results offer strong support for a model where optimal differentiation of human B cells to plasma cells is contingent upon receiving at least two signals: one signal is delivered to the surface immunoglobulin, and one signal delivered to the B cell in a T cell and/or monocyte dependent fashion (B cell growth and differentiation factors).

Graduated elastic compression stockings on a stroke unit: a feasibility study

BACKGROUND

thrombo-embolic complications are important causes of morbidity and mortality after acute stroke. Anticoagulant prophylaxis is contraindicated in intracerebral haemorrhage and not recommended in acute ischaemic stroke because of increased risk of cerebral haemorrhage. Graduated elastic compression stockings are a simple alternative but are not widely used in stroke patients, perhaps because of perceived contraindications and problems with tolerability.

OBJECTIVES

to establish the feasibility and tolerability of graduated compression stockings on a stroke unit.

DESIGN

we assessed 112 consecutive stroke patients for contraindications to and tolerability of graduated compression stockings.

MEASUREMENTS

we used clinical indices and ankle-brachial Doppler pressure measures to assess suitability. We prospectively assessed tolerability of the stockings.

RESULTS

Ninety-four (84%) of the 112 patients had no contraindications to the use of the stockings. The most common contraindication was an ankle-brachial index of <0.8. Other contraindications were marked dependent leg oedema (1/18) and severe venous ulceration. Eighty-nine (95%) of the 94 patients tolerated the stockings and wore them until discharge. Skin irritation was the most common reason for intolerance.

CONCLUSIONS

contraindications to the use of graduated compression stockings can be defined using clinical criteria and a Doppler machine to calculate an ankle-brachial pressure index. If this is done, tolerability is excellent. This approach may be a useful alternative in preventing venous thrombo-embolism in stroke patients.

Pregnant stewardess--should she fly?

There is much pressure on the airlines to allow stewardesses to fly while pregnant. Some of them want to fly in quite advanced stages of pregnancy. This paper offers a survey of the problem, the hazards that may occur and some guidelines for the physician. The author outlines the normal changes to be expected with advancing pregnancy and those factors that could have an adverse effect on a pregnant stewardess and her fetus, such as hypoxia, trauma, abortion, the hazards of travel, and flying itself. Certain legal problems of unemployment and medical disability also are discussed. Travel alone offers no real danger to the pregnant stewardess in the first trimester of pregnancy; however, because of the changing mechanics of her size, posture, and increasing unsteadiness, it would be wisest to require a pregnant stewardess to cease flying at 13 weeks, with an absolute prohibition of flying after the 20th week.

Analysis of Z-DNA in fixed polytene chromosomes with monoclonal antibodies that show base sequence-dependent selectivity in reactions with supercoiled plasmids and polynucleotides

Five monoclonal anti-Z-DNA antibodies were characterized with respect to their binding of synthetic nucleic acid polymers and of supercoiled circular plasmid DNA. All of the antibodies reacted only with DNA in the Z-conformation; however, they fell into two classes on the basis of sequence specificity. One class, with broad specificity, reacted well with all sequences in the Z-form, including poly(dG-dC), poly(dG-dm5C), and poly (dG-dBr5C) in linear polymers and poly(dG-dC)n and poly[(dC-dA)n.(dT-dG)n] sequences in supercoiled plasmids. The other class bound only Z-DNA formed by poly(dG-dC). Binding of the monoclonal antibodies specifically to inserts of Z-DNA-forming sequences in plasmids was mapped directly by cross-linking of antibody to the DNA, digestion with restriction nuclease, and electrophoretic analysis of both the unbound fragments and the bound fragments recovered from immune complexes. The monoclonal antibodies were used for indirect immunofluorescence staining of Drosophila polytene chromosomes fixed by two procedures. One procedure yielded chromosomes with Z-specific antibody binding in many interbands, a few specific bands, and parts of some puffs. On chromosomes fixed by the second procedure, antibody staining appeared to follow the DNA concentration, staining all bands brightly. For each fixation procedure, chromosomes showed the same staining pattern with each of the broad specificity monoclonal antibodies that had been seen with polyclonal antibodies. The antibodies that reacted only with poly(dG-dC) and poly (dG-dC)n plasmid inserts did not stain chromosomes fixed by either protocol. We conclude that stretches of poly(dG-dC)n sequences do not contribute significantly to the presence of Z-DNA in fixed polytene chromosomes of Drosophila melanogaster.

Development and internal validation of an algorithm to predict intraoperative risk of inadvertent hypothermia based on preoperative data

Intraoperative hypothermia increases perioperative morbidity and identifying patients at risk preoperatively is challenging. The aim of this study was to develop and internally validate prediction models for intraoperative hypothermia occurring despite active warming and to implement the algorithm in an online risk estimation tool. The final dataset included 36,371 surgery cases between September 2013 and May 2019 at the Vienna General Hospital. The primary outcome was minimum temperature measured during surgery. Preoperative data, initial vital signs measured before induction of anesthesia, and known comorbidities recorded in the preanesthetic clinic (PAC) were available, and the final predictors were selected by forward selection and backward elimination. Three models with different levels of information were developed and their predictive performance for minimum temperature below 36 °C and 35.5 °C was assessed using discrimination and calibration. Moderate hypothermia (below 35.5 °C) was observed in 18.2% of cases. The algorithm to predict inadvertent intraoperative hypothermia performed well with concordance statistics of 0.71 (36 °C) and 0.70 (35.5 °C) for the model including data from the preanesthetic clinic. All models were well-calibrated for 36 °C and 35.5 °C. Finally, a web-based implementation of the algorithm was programmed to facilitate the calculation of the probabilistic prediction of a patient's core temperature to fall below 35.5 °C during surgery. The results indicate that inadvertent intraoperative hypothermia still occurs frequently despite active warming. Additional thermoregulatory measures may be needed to increase the rate of perioperative normothermia. The developed prediction models can support clinical decision-makers in identifying the patients at risk for intraoperative hypothermia and help optimize allocation of additional thermoregulatory interventions.

[Chronic diarrhoea: the importance of an accurate medical history]

Four patients, two women aged 29 and 42 years and two men aged 45 and 34 years, with longstanding complaints of (watery) diarrhoea were referred for a second opinion after extensive and costly analysis, including numerous examinations. An accurate medical history revealed deviant food patterns with abundant intake of coffee and sugar or sugar-containing products like cola or sweeteners in all four patients. Coffee (and caffeine) has a stimulating effect on both intestinal motility and net secretion, possibly leading to diarrhoea. Over-consumption of sugars and sweeteners (sometimes added to medication) can also cause osmotic diarrhoea. In all four patients, dietary advice was sufficient to resolve the diarrhoea, thus emphasizing once more the importance of an accurate and complete medical history.