Heterogeneity of management practices surrounding operable gallbladder cancer - results of the OMEGA-S international HPB surgical survey

BACKGROUND

Gallbladder cancer (GBC) is an aggressive, uncommon malignancy, with variation in operative approaches adopted across centres and few large-scale studies to guide practice. We aimed to identify the extent of heterogeneity in GBC internationally to better inform the need for future multicentre studies.

METHODS

A 34-question online survey was disseminated to members of the European-African Hepatopancreatobiliary Association (EAHPBA), American Hepatopancreatobiliary Association (AHPBA) and Asia-Pacific Hepatopancreatobiliary Association (A-PHPBA) regarding practices around diagnostic workup, operative approach, utilization of neoadjuvant and adjuvant therapies and surveillance strategies.

RESULTS

Two hundred and three surgeons responded from 51 countries. High liver resection volume units (>50 resections/year) organised HPB multidisciplinary team discussion of GBCs more commonly than those with low volumes (p < 0.0001). Management practices exhibited areas of heterogeneity, particularly around operative extent. Contrary to consensus guidelines, anatomical liver resections were favoured over non-anatomical resections for T3 tumours and above, lymphadenectomy extent was lower than recommended, and a minority of respondents still routinely excised the common bile duct or port sites.

CONCLUSION

Our findings suggest some similarities in the management of GBC internationally, but also specific areas of practice which differed from published guidelines. Transcontinental collaborative studies on GBC are necessary to establish evidence-based practice to minimise variation and optimise outcomes.

A deep LSTM network for the Spanish electricity consumption forecasting

Nowadays, electricity is a basic commodity necessary for the well-being of any modern society. Due to the growth in electricity consumption in recent years, mainly in large cities, electricity forecasting is key to the management of an efficient, sustainable and safe smart grid for the consumer. In this work, a deep neural network is proposed to address the electricity consumption forecasting in the short-term, namely, a long short-term memory (LSTM) network due to its ability to deal with sequential data such as time-series data. First, the optimal values for certain hyper-parameters have been obtained by a random search and a metaheuristic, called coronavirus optimization algorithm (CVOA), based on the propagation of the SARS-Cov-2 virus. Then, the optimal LSTM has been applied to predict the electricity demand with 4-h forecast horizon. Results using Spanish electricity data during nine years and half measured with 10-min frequency are presented and discussed. Finally, the performance of the proposed LSTM using random search and the LSTM using CVOA is compared, on the one hand, with that of recently published deep neural networks (such as a deep feed-forward neural network optimized with a grid search) and temporal fusion transformers optimized with a sampling algorithm, and, on the other hand, with traditional machine learning techniques, such as a linear regression, decision trees and tree-based ensemble techniques (gradient-boosted trees and random forest), achieving the smallest prediction error below 1.5%.

Coronavirus Optimization Algorithm: A Bioinspired Metaheuristic Based on the COVID-19 Propagation Model

This study proposes a novel bioinspired metaheuristic simulating how the coronavirus spreads and infects healthy people. From a primary infected individual (patient zero), the coronavirus rapidly infects new victims, creating large populations of infected people who will either die or spread infection. Relevant terms such as reinfection probability, super-spreading rate, social distancing measures, or traveling rate are introduced into the model to simulate the coronavirus activity as accurately as possible. The infected population initially grows exponentially over time, but taking into consideration social isolation measures, the mortality rate, and number of recoveries, the infected population gradually decreases. The coronavirus optimization algorithm has two major advantages when compared with other similar strategies. First, the input parameters are already set according to the disease statistics, preventing researchers from initializing them with arbitrary values. Second, the approach has the ability to end after several iterations, without setting this value either. Furthermore, a parallel multivirus version is proposed, where several coronavirus strains evolve over time and explore wider search space areas in less iterations. Finally, the metaheuristic has been combined with deep learning models, to find optimal hyperparameters during the training phase. As application case, the problem of electricity load time series forecasting has been addressed, showing quite remarkable performance.

Giemsa and Grocott in the recognition of Histoplasma capsulatum in blood smears

OBJECTIVE

To facilitate the recognition of intracellular yeasts of Histoplasma capsulatum and differentiate it from Leishmania amastigotes and other parasites, using the combination of Giemsa and a rapid modification of Grocott stains to peripheral blood smears in a hematological study.

METHODS

The combination of both stains was applied consecutively (first Grocott and then Giemsa) to previously fixed peripheral blood smears. Microscopy was performed with 400× and 1 000×, the latter using immersion oil.

RESULTS

The yeasts of Histoplasma capsulatum were observed into the cytoplasm of leukocytes as brownish oval elements, with 3-4 µm in diameter.

CONCLUSIONS

The combination of both techniques is a simple and fast method to facilitate recognition of intracellular yeasts and it is different from intracellular parasitic elements. Moreover, it allows distinguishing the cell elements that are in the microscopic preparations. It may be very helpful in those cases in which the presumptive diagnosis of histoplasmosis has not been established yet and where other more sophisticated methods are not available.

Infections and inequalities: anemia in AIDS, the disadvantages of poverty

OBJECTIVE

To study anemia in AIDS patients and its relation with socioeconomic, employment status and educational levels.

METHODS

A total number of 442 patients who visited the Infectious Diseases University Hospital in Buenos Aires, Argentina were included in the study. Patients were dividied into two groups, i.e. one with anemia and the other without anemia. Anemia epidemiology and its relationship with educational level, housing, job situation, monthly income, total daily caloric intake and weekly intake of meat were evaluated.

RESULTS

Anemia was found in 228 patients (54%). Comparing patients with or without anemia, a statistically significant difference was found (P<0.000 1) in those whose highest educational level reached was primary school, who lived in a precarious home, who had no stable job or were unable to work, whose income was less than 30 dollars per month, whose meat consumption was less than twice a week or received less than 8 000 calories per day.

CONCLUSIONS

The high prevalence of anemia found in poor patients with AIDS suggests that poverty increases the risk to suffer from this hematological complication. The relationship between economic development policies and AIDS is complex. Our results seem to point to the fact that AIDS epidemic may affect economic development and in turn be affected by it. If we consider that AIDS affects the economically active adult population, despite recent medical progress it usually brings about fatal consequences, especially within the poorest sectors of society where the disease reduces the average life expectancy, increases health care demand and tends to exacerbate poverty and iniquity.

A case report of pulmonary coinfection of Strongyloides stercoralis and Pneumocystis jiroveci

A case of pulmonary coinfection by Strongyloides stercoralis and Pneumocystis jiroveci has been detected in an AIDS patient treated in the Respiratory Intensive Care Unit of the Muñiz Hospital. At diagnosis, the patient presented cough with mucopurulent expectoration, dyspnea, fever, bilateral pulmonary infiltrates on the chest X-ray, negative bacilloscopy for acid fast bacteria and a CD4(+) T lymphocytes count of 52 cells/µL. The microbiological diagnosis was achieved by microscopic observation of the respiratory secretions obtained by bronchoalveolar lavage, while the wet mount examination revealed rhabditiform and filariform larvae of the nematode and foamy exudates, pathognomonic of the pulmonary pneumocystosis. It was the unique case of this association among about 3 000 samples performed in our laboratory in the last 10 years and diagnosed by microscopy. Other complementary stains (a rapid modification of Grocott, Kinyoun and Giemsa) were applied to the smears after the diagnosis of mycotic and parasitary infections achieved by fresh microscopy. Both physicians and microbiologists should take into account the possible coexistence of respiratory pathogens in immunocompromised patients, such as those with AIDS.

Diagnosis of Mycobacterium tuberculosis using molecular biology technology

OBJECTIVE

To present an integrated molecular biology dedicated system for tuberculosis diagnosis.

METHODS

One hundred and five sputum specimens from patients strongly suspected by clinical parameters of tuberculosis were studied by Ziehl-Neelsen staining, by cultivation on solid medium and by a balanced heminested fluorometric PCR system (Orange G3TB) that could preserve worker safety and produce a rather pure material free of potential inhibitors. DNA amplification was performed in a low cost tuberculosis termocycler-fluorometer. Produced double stranded DNA was flurometrically detected. The whole reaction was conducted in one single tube which would not be opened after adding the processed sample in order to minimize the risk of cross contamination with amplicons.

RESULTS

The assay was able to detect 30 bacillus per sample mL with 99.8% interassay variation coefficient. PCR was positive in 23 (21.9%) tested samples (21 of them were smear negative). In our study it showed a preliminary sensitivity of 94.5% for sputum and an overall specificity of 98.7%.

CONCLUSIONS

Total run time of the test is 4 h with 2.5 real working time. All PCR positive samples are also positive by microbiological culture and clinical criteria. Results show that it could be a very useful tool to increase detection efficiency of tuberculosis disease in low bacilus load samples. Furthermore, its low cost and friendly using make it feasible to run in poor regions.

Rapid and biosecure diagnostic test for tuberculosis

Early and rapid detection of the causative organism is necessary in tuberculosis. We present here an integrated and dedicated molecular biology system for tuberculosis diagnosis. One hundred and eighty-nine (189) biologic specimens from patients strongly suspected by clinical parameters of tuberculosis were studied by Ziehl-Neelsen staining, cultivation on a solid medium, and by a balanced heminested fluorometric PCR system (Orange G3TB) that preserves worker safety and produces a rather pure material free of potential inhibitors. DNA amplification was carried out in a low cost using a tuberculosis thermocycler-fluorometer. The double stranded DNA produced is fluorometrically detected. The whole reaction is carried out in one single tube which is never opened after adding the processed sample, thus minimizing the risk of cross contamination with amplicons. The assay is able to detect 30 bacilli/ml of sample having a 99.8 % inter-assay coefficient of variation. PCR was positive in 36 (18.9 %) tested samples (33 of them were smear-negative). In our study, it yields a preliminary overall sensitivity of 97.4 %. In addition, its overall specificity is 98.7 %. The total run time of the test is 4 h with two and a half real working hours. All PCR-positive samples also had a positive result by microbiological culture and clinical criteria. The results obtained showed that it could be a very useful tool to increase efficiency in detecting the tuberculosis disease in low bacillus inoculum samples. Furthermore, its low cost and friendly usage make it feasible to be used in regions with poor development.

[Eccrine angiomatous hamartoma: a report of 2 cases]

Eccrine angiomatous hamartoma is a rare, benign tumor characterized by a proliferation of eccrine and vascular structures. We present 2 cases and review the characteristics of this disorder. The first patient was a 33-year-old woman who consulted for a brownish lesion on her back associated with local hyperhidrosis. The second patient was a 25-year-old man with an asymptomatic erythematous lesion on his left palm. In both patients a diagnosis of eccrine angiomatous hamartoma was made based on the histological findings. Eccrine angiomatous hamartoma is usually present at birth or develops during childhood. It is typically a solitary lesion and signs and symptoms can vary; diagnosis is therefore based on histological study. The most common site is on the distal parts of limbs. The lesions tend to be asymptomatic, but there may be associated pain and hyperhidrosis. Treatment is not usually necessary except in cases with persistent symptoms, excessive sweating, or cosmetic concerns.

[Risk analysis of foodborne diseases: microbial risk assessment]

The basic goals of risk assessment include the following: to identify potentially hazardous situations and apply appropriate methods to estimate the likelihood that a hazard occurs. In The uncertainty in that estimate, to provide alternative solutions to reduce the risk, estimate the effectiveness of those solutions, provide information to base a risk management decision, and estimate the uncertainty associated with the analysis. Risk analysis provides the rational framework for assembling and then analysing the evidence relating to risk and presenting the results in a form that is easy to understand and then act upon fairly and effectively. Progress made is no excuse for arrogance. The present review is definitely not designed as the last word on risk analysis for foodborne diseases. Rather, this review has been designed to continue an evolving and necessary process and to provide a reference point that indicates the state of development in 2010.

Cutaneous myiasis due to Cochliomyia hominivorax in a drug user

Myiasis is the condition resulting from the invasion of tissues or organs of man or animals by dipterous larvae. The blowflies (Calliphoridae) of Argentina comprise several species that may cause myiasis by colonizing wounds or infected body orifices, and one specific parasite: Cochliomyia hominivorax. This species often causes traumatic myiasis in cattle, dogs and cats, and it is not rare in humans. The larvae consume living tissues, so they are dangerous unless speedily removed. Immediate operative exploration along with the removal of larvae and primary defect closure is recommended in every case. Here we report a case of myiasis in a scalp wound caused by blunt force trauma to the area, in a male patient with a case history of alcohol and drug abuse. Seventy-one living larvae were extracted from the wound and determined as C. hominivorax in the Forensic Entomology Laboratory. Given the aggressiveness of these larvae, specific and quick diagnosis as well as the application of appropriate treatment is crucial.

Detection of Cryptococcus neoformans in faecal matter: a novel presentation of disseminated cryptococcosis

This item has no abstract. Use the links below to access the full article.

[Radiation on the dining table]

Zero tolerance to bacterial contamination means considering the acceptance of "radiation on the table". The process of food irradiation has been extensively studied, nevertheless its use remains a matter of some controversy. Despite unanimous agreement within the medical community of the safety of this procedure, occasional concerns arise from the consumers. A common consumer misconception is that irradiation may turn the food "radioactive". A significant number of scientific studies on the topic were analyzed. We found no scientific study demonstrating that consumption of irradiated food might pose a risk to consumers. All studies conclude that food irradiation at the appropriate dose required to reduce contamination is safe and does not affect its nutritional value. In order to emphasize the issue we discuss the potential benefit vs harm of irradiation of food contaminated with E. coli 0157: H7. The association of this bacteria with severe disease and death has been clearly established in contrast with the lack of a demonstrated risk due to meat irradiation. We conclude that the risks of food irradiation remains "unknown" simply because, after four decades of research, none has been identified. In contrast to the risks of acquiring a food transmitted bacterial disease, the risk of irradiation is negligible.

Food-borne botulism in Argentina

Botulism is a severe neuroparalytic disease caused by Clostridium botulinum toxins. Although the disease is uncommon it is a cause of great concern due to its high rate of mortality. Food-borne outbreaks of botulism occur worldwide and require immediate public health attention and acute care resources. Analysis of outbreaks showed that the food products most often involved were fermented fish products in Alaska; home-canned food, oil preservation and restaurant sauce in the rest of the United States (US) and in London and; and home-canned vegetables, airtight packed food with inappropriate refrigeration, and aerosols in Argentina. The diagnosis is based only on clinical findings matching the disease and previous exposure to suspicious food. Botulism must be immediately identified as even one case suggests the start of an epidemic and should be treated as a public health emergency. Therefore, the purpose of the following review is to recognize the risks associated with the consumption of potentially dangerous foods, and to encourage prevention by seeking to make all public health professionals aware of the dangers of this potentially lethal disease.

[Listeria monocytogenes outbreaks: a review of the routes that favor bacterial presence]

Listeria monocytogenes is a foodborne pathogen that causes serious invasive illness, mainly in certain well-defined high-risk groups, including immunocompromised patients, pregnant women and neonates. L. monocytogenes primarily causes abortion, septicaemia or infections of the central nervous systems. Listeriosis outbreaks have mostly been linked to consumption of raw milk or cheese made of unpasteurized milk. Previous outbreaks of listeriosis have been linked to a variety of foods especially processed meats (such as hot dogs, deli meats, and páté). The public health importance of listeriosis is not always recognized, particularly since listeriosis is a relatively rare disease compared with other common foodborne illnesses such as salmonellosis or botulism. However, because of its high case fatality rate, listeriosis ranks among the most frequent causes of death due to foodborne illness: second after salmonellosis. Changes in the manner food is produced, distributed and stored have created the potential for widespread outbreaks involving many countries. The pasteurization of raw milk, which destroys L. monocytogenes, does not eliminate later risk of L. monocytogenes contamination in dairy products. Extensive work has been ongoing in many countries during the last decade to prevent outbreaks and decrease the incidence of listeriosis. A marked reduction has occurred in its incidence in some of these countries during the 1990s, suggesting a relationship between preventive measures and reduction on human cases listeriosis.

[Epidemiology and risk factors associated to foodborne and infant botulism: where and when?]

Foodborne botulism is caused by ingestión of a preformed toxin produced in food by C. botulinum. The most frequent source is home-canned foods, in which spores that survive an inadequate cooking and canning process germinate, reproduce, and produce this toxin in the anaerobic environment of the canned food. From 1992 to 2003, 34 cases of food-borne cases and 275 cases of infant botulism were reported in Argentina. The severity of symptoms depends on the amount of toxin ingested. Mild cases may not seek medical attention at all. A patient presenting only nausea and mild neurological symptoms may not raise the physician's attention and therefore the case will not be reported. It is important to make physicians aware of this potentially fatal disease. In Argentina, most botulism cases are related to home-canned food. Therefore, botulism can be prevented through the education of consumers in order to discourage the consumption of that kind of food.

CNS cryptococcoma in an HIV-positive patient

This is the first case of brain cryptococcoma in an AIDS patient reported in Argentina. The patient was a 28-year-old white heterosexual man with AIDS who presented with altered mental status, seizures, visual hallucinations, headache, and fever without significant focal neurological deficit. He had a lumbar puncture, and was treated for cryptococcal meningitis. Subsequent brain CT scanning and MRI disclosed a mass lesion in the occipital lobe. Histopathological examination of biopsy was compatible with cryptococcoma, and tissue culture revealed Cryptococcus neoformans. Resolution of the mass and edema resulted after treatment with intravenous amphotericin B for six weeks, which was followed with maintenance oral fluconazole. Intracranial mass is an uncommon complication in AIDS patients with cryptococcosis, and cryptococcoma should be considered as differential diagnosis of brain mass lesion in these patients. The etiologic diagnosis is necessary because central nervous system (CNS) toxoplasmosis, lymphoma, and tuberculoma can produce similar clinical syndromes and MRI or CT findings to cryptococcoma. Also, these pathologies may coexist with meningeal cryptococcosis.