Epidemiologie Mikrobiologie Imunologie最新文献

Objective: To determine the sensitivity and specificity of the Abbott ID-NOW™ test in the diagnosis of COVID-19. The test is based on the detection of the SARS-CoV-2 gene by isothermal amplification technology.

Methods: From 303 individuals, two nasopharyngeal swabs and one oropharyngeal swab were collected to be tested in parallel by the ID-NOW™ test and PCR test (Allplex™ SARS-CoV-2 Assay). A subgroup of 107 individuals presented to the public collection point for covid-19 at the Motol University Hospital during the dominance of the Delta variant, and the others were tested via the Adult Emergency Admission Department during the dominance of the Omicron variant.

Results: Of 297 valid samples, 43 were positive by the PCR assay and 33 were positive by the ID-NOW™ test (sensitivity 76.74%; 95% CI 61.37 to 88.24%). ID-NOW™ detected three samples as positive, but the positivity was not confirmed by PCR (specificity 98.82%; 95% CI 96.59 to 99.76%). A significant increase in sensitivity up to 100% is observed for samples with a higher viral load (with a PCR threshold cycle value below 30 or from patients with symptoms of COVID-19). The Delta or Omicron variant has no significant effect on the sensitivity of the test.

Conclusion: Due to its ease of use and speed of result, ID-NOW™ is a suitable diagnostic tool for prompt assessment of a patient's infectivity. If, despite the negative ID-NOW™ result, the patient has symptoms of COVID-19, it is advised to perform a classic PCR test for SARS-CoV-2.

Hypervirulent strains of Klebsiella pneumoniae (hvKP) can cause atypical multilocular infections in otherwise healthy patients. Diagnosis of infection caused by hvKP is based mainly on clinical findings and laboratory results, including detection of virulence genes. It typically manifests as hepatic abscess with metastatic spread. Treatment is based on surgical intervention in combination with targeted antimicrobial therapy. The occurrence of hvKP infection is relatively common in Asia, and while still rare in Europe, incidence is increasing. The article aims to provide a short overview of the issue and increase awareness of the possible occurrence of hvKP infections.

Streptococcus pyogenes causes a variety of human diseases ranging from uncomplicated respiratory tract and skin infections to severe invasive diseases possibly involving toxic shock syndrome. Besides the emm gene-encoded M protein, important virulence factors are pyrogenic exotoxins, referred to as superantigens. The National Reference Laboratory for Streptococcal Infections has newly introduced bioinformatics tools for processing S. pyogenes whole genome sequencing data. Using the SRST2 software and BV-BRC platform, WGS data of 10 S. pyogenes isolates from patients with invasive disease were analysed, and emm type, sequence type, and superantigen encoding gene profiles were determined. The Unicycler assembly pipeline with the SPAdes de novo assembler was used to assemble genome sequences from short reads.

Introduction: Q fever is a zoonosis with a worldwide occurrence. Coxiella burnetii infection is most commonly transmitted by inhalation of air containing contaminated dust in cow, sheep and goat farming areas. The other modes of transmission are alimentary route (ingestion) and through sucking ticks. We set ourselves the goal of presenting a descriptive analysis of cases of Q fever in the Czech Republic (CZ) and former Czechoslovakia and draw attention to this often-overlooked issue.

Methods: Summary of available information about Q fever was processed, and a narrative search of published cases of Q fever in the CZ and former Czechoslovakia, in Czech, Slovak and English, without time restrictions was performed. Furthermore, a descriptive analysis of Q fever cases reported to the Czech infectious diseases reporting system in 1982-2021 was done. After analysis, the available information system data were supplemented with data from a search of published scientific literature and weekly reports on the current epidemiological situation of the public health protection authorities of the CZ.

Results: The disease has been reported in former Czechoslovakia and then in CZ since 1952. In 1952-1954, six outbreaks were reported with a total of 150 cases, mostly in connection with work with cattle. In 1980, a large-scale outbreak of Q fever affected 526 employees of the cotton production plant at Staré Město near Uherské Hradiště. Otherwise, units to dozens of cases were reported. From 1993 to 2021, 27 cases of the disease were detected in the CZ, of which 22 (81.5%) occurred in men. The age range was 0-60 years (mean 31, median 30 years). Seasonality by reporting month was highest in January and September.

Conclusion: There has been a decline in human cases of Q fever in the European Union (EU) in recent years, and only few cases of the disease occur in the CZ. Still, due to potential severity of the disease, the current climate change with the consequent increase in the spread of ticks as vectors of Coxiella, and animal movements associated with the global market, it is important to consider Q fever in the differential diagnosis. As part of the prevention, it is necessary to ensure compliance with basic hygiene rules, especially in at-risk occupations, and to consume only pasteurized dairy products. Vaccination of humans is not available in EU countries, although vaccination of livestock is possible.

Babesiosis is a less common but important tick-borne infectious disease. Over the last 50 years, an increasing number of cases have been reported worldwide, especially in the USA. The northern part of the US is an endemic area where the incidence has risen to 2,000 cases per year in the last decade. Babesia microti, a parasite of small rodents, is the cause of most of these infections in that region. In Europe, 56 autochthonous cases of human babesiosis have been reported since 1957. Most of them were caused by the species Babesia divergens, a parasite of cattle. Since 1992, 13 cases of B. microti infection have been imported from North America into Europe. The disease is serious especially for splenectomised and immunocompromised patients. Although the most important vector of babesiosis in Europe is the tick Ixodes ricinus, infection was transmitted through blood transfusion in number of patients, which can be fatal for immunosuppressed patients. The diagnosis of babesiosis is based on the identification of intraerythrocytic parasites in a blood smear, PCR detection of Babesia DNA, and determination of antibodies by serology and immunofluorescence assays. The disease is treated with antibiotics (azithromycin or clindamycin in a severe course of the disease) and quinine. The increase in human babesiosis is not only due to climate change and tick activity, outdoor leisure activities, and increased human migration, but an important role is also played by improved molecular methods and growing awareness of the disease.

Endogenous retroviruses (ERVs) are genetic elements that were integrated into the host genome more than 100 million years ago. Their integration took place in germ cells, ensuring their vertical transmission in the human population. They are currently thought to make up to 8 % of the human genome. During evolution, various mutations have accumulated in endogenous retroviruses, leading to their dysfunction, and were therefore considered as junk DNA in the past. However, in recent years it has turned out that they are not completely dysfunctional. With more data becoming available from human genome analyses, their potential roles in the human body are being revealed.

Aim: In the past, Pneumocystis jirovecii belonged to the Protozoa group, but is currently taxonomically included in the kingdom Fungi. P. jirovecii is an opportunistic pathogen, responsible for pneumocystis pneumonia with frequent complications of immunocompromised patients. Delayed initiation of appropriate therapy increases the risk of death in immunocompromised patient. The aim of this work was to determine and evaluate the reliability of methods of laboratory diagnosis of pneumocystosis used in routine laboratories as well as the occurrence of this disease in patients from Slovakia during 19 years.

Material and methods: The diagnosis is based on microscopic examination (Giemsa- and Gram-Weigert-staining) and detection of parasite DNA by classical or real-time PCR in bronchoalveolar lavage and sputum.

Results: Pneumocysts were detected in 190 persons (5.7%) from the whole group of patients. Cancer patients represented the riskiest group in terms of pneumocystosis, which was confirmed by the highest percentage (57.9%) of individuals infected with P. jirovecii. Compared with the PCR, 33.7% sensitivity and 100% specificity of microscopy was calculated by using a binary classification test. Molecular methods are more sensitive in the detection of P. jirovecii compared to microscopic evidence and currently represent a reliable detection system in the diagnosis of pneumocystosis.

Conclusion: In view of the increasing number of immunocompromised persons, diagnostics of P. jirovecii in patients with pulmonary complications is essential. This was also confirmed in our study, where the number of examinations and detection of this opportunistic pathogen increased over the years.

Lung cancer (LC) is one of the most frequently diagnosed cancers and one of the leading causes of cancer deaths in the Czech Republic, the prevalence of which is steadily increasing. There is scientific evidence that LC screening through low-dose computed tomography (LDCT) reduces the risk of death from LC. No systematic LC screening strategy has been currently in place in the Czech Republic. Since the beginning of 2022, the methodology of early detection of LC using LDCT has been piloted to test the feasibility of the screening program. The primary purpose of the project is an early and accurate diagnosis of the disease, which, in combination with follow-up treatment, will lead to a reduction in LC mortality. The pilot data will definitely serve as a basis for an expert discussion of the acceptability of the program to the Czech population and its impact on the healthcare system. It is clear that by introducing such a screening program, we will join the countries that, based on scientific data, enable the population to profit from an actively implemented LC prevention strategy. Public awareness of the benefits of early non-invasive LC detection can contribute to higher compliance of at-risk persons and their willingness to participate in the program. The key role in the entire process is played by general practitioners and/or outpatient pulmologists who address at-risk individuals and can positively influence their involvement in the program.

Aims: The primary aim of our monitoring was to determine the duration of persistence of antibody levels following administration of the Comirnaty (Pfizer/BioNTech) mRNA vaccine. The second aim was to analyse the effect of selected factors on the level of antibodies.

Methods: The study cohort consisted of 250 employees of the Medirex JSC laboratories. For the quantitative determination of specific IgG anti-S1 and anti-S2 antibodies to SARS-CoV-2, chemiluminescence immunoassay was used. Twenty-nine subjects were excluded from the analysis due to extreme values of antibody levels in individual measurements. The effect of gender, age, BMI, comorbidity, and adverse reactions after vaccination with the Comirnaty (Pfizer/BioNTech) mRNA vaccine on antibody levels was analysed. Comparisons were made for five samples collected from two weeks after the 1st dose to 36 weeks after the 2nd dose of the mRNA vaccine. After the fifth sampling, the cohort was divided into two groups. Group 1 received the 3rd dose, and Group 2 were controls. We performed the last (sixth) sample collection two weeks after booster administration in Group 1and 11 months after the 2nd dose of the vaccine in controls. Between months 8 and 10 after the 2nd dose, we performed a cellular immunity test.

Results: Altogether 99.6% of the participants had a positive antibody level at week 36. Antibodies were still present in controls at month 11 after the 2nd dose. Significantly higher antibody levels were found in females, younger subjects, and those with selected adverse reactions. Reactive specific T lymphocytes were present in 65.6% of the subjects between weeks 36 and 44.

Conslusion: The antibody response decreased with the time since the 2nd dose but was still present in the control group at week 48. The effect of booster on antibody levels was clearly demonstrated. We have not confirmed an association of cellular immunity with the level of antibodies or with the antibodies present.

The annual number of diagnosed diseases caused by non-tuberculous mycobacteria in predisposed individuals remains constant in the Czech Republic. Their clinical characteristics vary depending on the properties of the causative species and its presence and quantity in the immediate environment of the patient. The most common clinically relevant species are Mycobacterium avium, M. kansasii, and M. xenopi. The most important source of M. avium is peat and products derived from it. M. avium may colonise warm water systems, posing a high risk of exposure to users (jacuzzi users in particular). M. kansasii is still present in waters of areas affected by industrial and mining activities. Its recently isolated genetic variants are mostly of no clinical significance but may be present as contaminants in medical preparations. M. xenopi permanently colonises most warm water systems, and its practical ubiquity makes difficult the interpretation of ambiguous findings on imaging. The antibiotic treatment, which may not always be successful, should be initiated after a comprehensive assessment of the patient's condition, imaging data, and disease progression. Similarly, the results of laboratory tests may not always be authoritative in decision making.