Epidemiologie Mikrobiologie Imunologie最新文献

Acute gastroenteritis is commonly seen in pediatric clinical practice. It is a largely self-limited disease with a benign course. We present a case of teenager with gastroenteritis resulting in severe acute kidney injury. The decline in glomerular filtration was so significant that renal replacement therapy had to be initiated. We had to continue in intermitent hemodialysis for seven days until sufficient improvement in renal function. Clostridioides difficile was identified as a cause of vomiting, bloody diarrhea and subsequent dehydration. To our knowledge, this is the first reported case of C. difficile-associated diarrhea accompanied by acute kidney injury requiring renal replacement therapy in a child.

Aim: Invasive meningococcal disease (IMD) is still a major threat not only to the youngest age group of children but also to adolescents and young adults. Higher rates of meningococcal disease have also been reported in specific at-risk groups, such as secondary and tertiary students and members of the military. Infection occurs after close contact with a clinically ill individual, but most often with an asymptomatic carrier. The aim of our study was to determine the prevalence of carriage of N. meningitidis in young persons newly enlisted in the Army of the Czech Republic (ACR).Material and methods: During August 2021, persons entering the service in the ACR were asked to participate in the presented study approved by the Ethics Committee. Nasopharyngeal and oropharyngeal swabs were collected from the study participants in August. A questionnaire survey was administered to each of them after signing an informed consent form. The biological samples were cultured on the day of collection and analysed for N. meningitidis. In case of meningococcal detection, the serogroup of N. meningitidis was determined. For most of the study participants, swabs were repeated after 2-3 months, in October and November. Swabs were also collected from additional participants, namely students entering the first year of bachelor and master studies at a military college.Results: A total of 252 newly recruited young military professionals, 201 males and 51 females, were included in the study. Carriage of N. meningitidis was found in 13 study participants, i.e., 5.2 % of all tested subjects, with a predominance of positive findings in the summer period. All carriers were males while in females, meningococcal carriage was not detected. In carriers, serogroup B was predominant over non-groupable isolates (NG). There was no evidence of carriage of meningococcal groups A, C, W, X, or Y. Meningococcal isolation was significantly more successful from oropharyngeal compared to nasopharyngeal swabs. Only in five of 17 positive findings, meningococci were detected from both the oropharynx and nasopharynx. No isolation was made from the nasopharynx alone.Conclusion: The lower percentage of meningococcal carriage in young military professionals in the Czech Republic in the study period 2021 as compared to similar reports on military collectives from other countries can be attributed to the current epidemic situation, where the measures taken in connection with the efforts to prevent the spread of COVID-19 resulted in the loss of seasonality of respiratory diseases and also their significantly lower incidence. This correlates with a reduction in carriage in the monitored age category.

Aim: To assess the trends and changes in the incidence of invasive disease caused by Haemophilus influenzae in the Czech Republic (CR) between 1999 and 2020 with regard to the introduction of childhood vaccination against H. influenzae serotype b (Hib) in 2001. Characterization of strains by multilocus sequence typing (MLST) and search for correlations between serotypes, sequence types, and patient groups or clinical manifestations of the disease.

Material and methods: A total of 623 invasive H. influenzae strains from surveillance of invasive Haemophilus disease in the Czech Republic were analysed. All strains were biotyped based on phenotypic characteristics and serotyped using slide agglutination with specific a-f antisera. Three hundred and eighty-three strains from the collection of the National Reference Laboratory for Haemophilus Infections (NRL HEM) originating from surveillance in the CR were analysed by MLST and assigned to sequence types (ST). For analyses, the dataset was supplemented with five strains from the PubMLST database of serotypes rarely or not at all found in the CR. Similarity calculations based on MLST and strain (serotype, biotype, ST) and patient (diagnosis, sex, age) data were performed in BioNumerics 7.6.

Results: After the introduction of Hib vaccination in 2001, a dramatic decline of more than 90% was observed in invasive Hib disease over the following years. Between 1999 and 2020, a total of 623 cases of invasive disease caused by H. influenzae were recorded in the CR, with about 20 cases reported annually in recent years. At present, the dominant agents causing Haemophilus invasive disease in the CR are non-enveloped strains (HiNT) followed by strains of Hif and Hie serotypes. The most common manifestation of Haemophilus invasive disease in the pre-vaccination era was meningitis, while now it is sepsis. Sequence types of 383 strains from the NRL HEM collection originating from surveillance in the CR were analysed. The results showed high clonality of the encapsulated strains and diversity of HiNT strains, which is consistent with the results of others. Strain similarity analysis showed no demonstrable relationships between patient age or clinical manifestation and serotype and ST.

Conclusion: In invasive Haemophilus disease, there has been a dramatic change as a result of Hib vaccination after 2001, with a reduction of cases caused by Hib from tens to units annually. In the last decade, the situation in the CR has been stable with no significant changes in the number of cases or in the representation of causative serotypes and is in line with the reports from other EU countries. In order to monitor further developments, it is desirable that the NRL HEM should continue the surveillance of invasive disease caused by H. influenzae, including molecular biological characteristics of strains. MLST allows the characterisation of stra

Vibrio spp. are Gram-negative rod-shaped bacteria commonly present in marine, estuarine and natural freshwater environments. A few members of this genus are associated with human diseases. Here we present the study of Vibrio spp. isolations from 20 artificial recreational pools in Slovakia. Water samples were collected from artificial pools filled with mineralized thermal water in eight recreational areas in Slovakia in 2019 and 2020. Ninety six out of 176 samples were positive for Vibrio spp. Totally 118 different strains of Vibrio spp. were isolated, from which 77 belonged to potentially pathogenic species - V. cholerae (34 isolates), V. vulnificus (4 isolates), V. furnissii (3 isolates), V. fluvialis (25 isolates), V. alginolyticus (10 isolates) and V. mimicus (1 isolate). To our knowledge this is the first study demonstrating the presence of pathogenic or potentially pathogenic Vibrio spp. in artificial pools filled with thermal mineralized waters even disinfected with chlorine compounds.

Aim: Colistin resistance poses a serious clinical problem. This study aims to investigate the presence of plasmid-mediated resistance and heteroresistance among Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) clinical isolates at intensive care units of Main Alexandria University Hospital.

Material and methods: Seventy colistin-resistant and 30 colistin-susceptible K. pneumoniae and E. coli isolates constituted the material of the study. The rapid polymyxin NP (Nordmann Poirel) test was performed. Heteroresistance in colistin-susceptible isolates was investigated by population analysis profile. mcr-1 and mcr-2 genes were amplified by polymerase chain reaction (PCR).

Results: The rapid polymyxin NP test showed 100% concordance with the results of BMD (broth microdilution method). Heteroresistance to colistin was detected in 23.3% of colistin-susceptible K. pneumoniae isolates. All colistin-resistant isolates were negative for mcr-1 and mcr-2 genes.

Conclusions: The rapid polymyxin NP test is a reliable screening tool for colistin resistance, but not for heteroresistance. Other colistin resistance mechanisms should be investigated.

Objective: To point out possible infection with SARS-CoV-2 in symptomatic patients despite repeated negative nasopharyngeal swab tests for SARS-CoV-2.

Material and methods: A retrospective observational study carried out at the Na Bulovce Hospital from the beginning of the pandemic until November 2020 included patients (1) who had symptoms compatible with COVID-19; (2) whose nasopharyngeal swab PCR tests in the presence of acute respiratory infection symptoms yielded two consecutive negative results; (3) in whom SARS-CoV-2 infection was subsequently confirmed by serology. Basic demographic and epidemiological data, symptoms, laboratory test results, X-ray findings and timing of virological tests were analysed for these patients.

Results: Seventeen patients met the inclusion criteria, 14 men and three women, aged 19-84 years with a median of 59 years, of whom 14 were hospitalized and three were treated as outpatients. Only seven patients were aware of the previous contact with an infected person. The main symptoms were fever, cough, headache, weakness, fatigue and shortness of breath. Pneumonia was found in 12 patients, four of whom developed respiratory insufficiency requiring ventilatory support. Most patients showed a uniform combination of haematological, biochemical and radio-logical findings: absence of eosinophils and increased polymorphonuclear/lymphocyte ratio; elevation of serum lactate dehydrogenase; elevation of CRP without rise of procalcitonin; typical chest CT or X-ray findings. All patients recovered. Coronavirus antigen test was performed in six patients, with all of them testing negative. SARS-CoV-2 infection was confirmed serologically by the detection of specific IgG and IgA in all 17 patients and also IgM in six patients, not before day 8 of the onset of symptoms.

Conclusions: Our study showed that some patients with acute COVID-19 may test repeatedly negative by nasopharyngeal swab PCR. These cases should be interpreted as a low viral load in the upper respiratory tract rather than false negativity of PCR. Such alternative is not envisaged in the algorithms used. Considering our results, the following recommendation can be made: If, despite negative PCR tests, COVID-19 is still suspected based on clinical symptoms and epidemiological evidence, preliminary diagnosis can be made on the basis of comprehensive assessment of the laboratory test and X-ray findings. Final confirmation of the aetiology relies on serological tests performed two weeks after the onset of symptoms.

Introduction: The increase in measles cases in early 2019 led to the implementation of several preventive measures focused mainly on health care providers. The study aimed to evaluate the seroprevalence of measles antibodies among employees of a large hospital and, a year apart, the rate of seroconversion in a pilot sample of the revaccinated subjects.

Methods: In 3027 employees of the University Hospital Olomouc, specific immunoglobulin G levels were tested on a voluntary basis. Those with insufficient levels were offered a booster dose. About approximately one year after the booster dose, the same test was performed in a sample of 52 employees.

Results: Of the tested subjects with a mean age of 41.8 ± 9.2 years, 54.0% were seropositive. A higher proportion of seropositivity as well as higher absolute values of antibody titers were noted in those born before routine vaccination was introduced in 1969. A total of 80.9% of the seronegative subjects opted for a booster dose. Seroconversion occurred in 73.2% of retested subjects. The relative increase of post-booster antibody titers was moderately correlated with age (r = 0.47, p < 0.05).

Conclusion: The proportion of seronegative employees of a large hospital reached 46.0%, being higher in younger individuals. Seroconversion occurred in 73.2% of booster dose recipients included in a pilot sample for reanalysis. A statistically significant correlation was noted between the relative increase of antibody titers and age.

Tuberculosis diagnosis and drug susceptibility testing (DST) are considered a priority for prompt initiation of effective therapy, increasing the chance of cure, decreasing the development of resistance, and reducing transmission.

Aim: Our objective was to evaluate currently applied diagnostic tools for tuberculosis including microscopic examination, GeneXpert, culture, and microscopic observation drug susceptibility (MODS) assay, investigating MODS assay usage for second line DST against culture based methods.

Material and methods: In this study the 120 sputum samples collected from suspected cases were over one year duration from December 2018 to January 2020. The samples were subjected to ZN microscopic examination, GeneXpert, MODS assay, and culture for detection of mycobacteria. Moreover, resistance to 5 drugs: isoniazid, rifampicin, ofloxacin, levofloxacin, and amikacin were tested using MODS against the proportion method.

Results: The sensitivity and specificity of the MODS assay were similar culture method with the advantage of obtaining the results in a median time of 10.7 days. Whereas the specificity of ZN and GeneXpert was high among untreated cases and decreased in subjects with a history of treatment. Monoresistance was the most common form of resistance detected among new cases followed by multidrug resistance, with a categorical agreement between the two methods above 90% for all tested drugs.

Conclusions: MODS assay is an attractive option once standardized for second line susceptibility testing and GeneXpert assay is of high sensitivity for rapid detection of MTB and RIF resistance especially in treatment naive cases.

Objective: The monitoring of influenza virus resistance is a routine part of influenza virus surveillance conducted by the National Reference Laboratory for Influenza and Non-Influenza Respiratory Viral Diseases (NRL/INI) at the National Institute of Public Health (NIPH). The aim is to detect neuraminidase inhibitor (oseltamivir) resistance in patients diagnosed with influenza.

Material and methods: A total of 326 influenza virus isolates from tissue culture were included in the study. They were obtained from inpatient and outpatient nasopharyngeal swabs which were referred to the NRL/INI during the seasons 2013/2014 to 2019/2020 and turned out to be RTPCR (reverse transcription polymerase chain reaction) positive for RNA (ribonucleic acid) of influenza virus A or B. The MDCK (Madin-Darby canine kidney) tissue culture cells were used for virus isolation from nasopharyngeal swabs. Oseltamivir resistance was tested using the NA-Star Influenza Neuraminidase Inhibitor Resistance Detection Kit (Applied Biosystems, Foster City, CA).

Results: Nine of 326 positive specimens were oseltamivir resistant. Resistant strains showed IC50 values 100 times as high on average as those in oseltamivir sensitive strains.

Conclusions: Monitoring influenza virus resistance is helpful in controlling reasonable prescription of antivirals and thus becomes an integral part of influenza virus surveillance. Antiviral resistance monitoring is necessary not only in hospitalized patients on antivirals but also in symptomatically treated outpatients as the detection of antiviral drug resistant strains in the latter group can suggest the emergence and/or spread of antiviral drug resistance in the population.

Aim: The aim of our work was to summarize the most important knowledge about listeriosis in humans and to analyse available epidemiological data on this disease in the Czech Republic in 2008-2018.

Methods: We conducted a literature search and descriptive epidemiological analysis of all human Listeria cases reported to the national surveillance system of infectious diseases (EpiDat until 2017, ISIN for 2018) in the Czech Republic in 2008-2018. For data management and analysis, MS Excel 2010 was used. The incidence maps were created using the ECDC Map Maker tool (EMMa).

Results: In total, 380 cases of human listeriosis (mean annual incidence of 0.33/100 000 inhabitants) were reported in the Czech Republic in 2008-2018. The highest age specific incidence was detected in 0-year-olds (1.85/100 000) and then in persons over 60 years (mean incidence of 0.95/100 000). Altogether 222 cases were detected in men (mean incidence of 0.39/100 000) and 158 in women (mean incidence of 0.27/100 000). Geographically, the highest mean annual incidence was reported in the Moravian-Silesian Region (0.6/100 000) and Pilsen Region (0.57/100 000). As many as 96.3% of the reported cases required hospital admission. Of 81 deaths related to listeriosis, 50 were directly caused by listeriosis. The highest monthly incidence was observed in June through October and then in January.  The incidence of listeriosis in the CZ shows an oscillating trend over the last 11 years. Neither epidemics nor imported cases were reported to the national surveillance system during the study period.

Conclusions: Listeriosis cases have been on the rise in the European Union (EU) over the last years, while in the CZ, an oscillating and slightly increasing trend has been observed. Generally, cases are reported mostly in the population aged over 64 years (and especially after the age of 84). As there is no vaccine available yet against this disease, the only option is the prevention, i.e., health education of consumers in general and of the risk groups in particular, and compliance with food safety and hygiene standards in food production and handling.