Burkholderia pseudomallei and Burkholderia mallei are etiologic agents of glanders and melioidosis, the particularly dangerous infections of animals and humans, and are attributed to potential agents of bioterrorism. The manifestation of diseases ranges from acute septicemia to chronic infection, any organs and tissues are affected, andtreatment requires long intravenous and oral antibiotic courses. The endemic zone of glanders and melioidosis covers spacious regions in the world, and the number of imported cases to temperate regions is constantly increasing. For the Russian Federation, glanders and melioidosis are «forgotten» and «unknown» infections, and this review presents current data on their distribution in the world, epidemiological aspects, and laboratory diagnosis features.
Melioidosis is a particularly dangerous infection with endemic distribution caused by the Gram-negative microorganism from the pathogenicity group II Burkholderia pseudomallei. In endemic countries, melioidosis holds one of the leading places in mortality rate after HIV, tuberculosis and, in recent years, COVID-19. The natural ecological pathogen niches are located in tropical and subtropical climate zones, primarily in Southeast Asia and Australia, where its existence as a species is maintained in moist soil and water in a certain temperature environmental range. However, at present, more and more often cases of melioidosis are registered outside endemic territories, which emphasizes the relevance of improving the means and methods of laboratory diagnostics of this disease both for countries located in the zone of natural foci as well as for local healthcare of the countries after importation of this poorly known infection into their territory. In such countries, including the Russian Federation, the population has no natural immunity to the pathogen, and therefore this infection acquires even greater clinical and epidemiological significance. In the Volgograd Plague Control Research Institute, an erythrocyte antigenic melioidosis diagnostic agent for IHA was designed allowing to detect the presence of serum melioidosis antibodies. The diagnostic agent was obtained on the basis of a biological carrier ram erythrocytes sensitized with isolated protein antigenic complexes of B. pseudomallei. The high analytical characteristics of the diagnostic agent were confirmed on sera models of immunized and recovering experimental animals. Using the obtained set of reagents, the level of serum antibodies against the causative agent of melioidosis was studied in residents from the 3 provinces of Vietnam (Ha Giang, Lang Son and Quang Ninh), as well as in control group composed of residents of the Volgograd region. In samples obtained from a non-endemic region, not more than 25% of cases contained IHA titers at lower than 1:10 dilution, which is apparently due to cross-reactivity of serum immunoglobulins. Positive serum samples from clinically healthy residents of Ha Giang, Lang Son and Quang Ninh provinces were at a titer of 1:10 detected in 71.5%, in dilutions of 1:201:80 in 28.5% of cases. Thus, we believe that serum antibody titer of 1:80 established in the IHA results, has a diagnostic significance, reflecting the intensity of the anti-melioidosis populational immunity.
Федеральная служба по надзору в сфере защиты прав потребителей и благополучия человека Федеральное казенное учреждение здравоохранения «Волгоградский научно-исследовательский противочумный институт», Волгоград, Россия Мелиоидоз относится к категории особо опасных бактериальных инфекций и против возбудителя мелиоидоза-Burkholderia pseudomallei-специфическая профилактика пока не разработана, хотя исследования в этом направлении (зарубежные и отечественные) продолжаются более 100 лет. В связи с этим разработка схем лечения и экстренной профилактики мелиоидоза является на сегодняшний день весьма актуальной задачей. Для повышения эффективности экстренной профилактики мелиоидоза в экспериментах на белых мышах были использованы препараты синтетических пептидов (бестим, имунофан) и тиопоэтинового препарата глутоксим при их совместном применении с антибиотиком доксициклином. Кроме того, в опытах на белых мышах была оценена способность гетерологичных вакцин (чумной и туляремийной), примененных в режиме экстренной профилактики, повышать резистентность животных к мелиоидозной инфекции. Показано, что из трех синтетических иммуномодуляторов более эффективным оказался имунофан, который при совместном применении с доксициклином повышал на 20% выживаемость от заражения 5 ЛД 50 Burkholderia pseudomallei и существенно увеличивал среднюю продолжительность жизни мышей при заражении 5-12 ЛД 50 (р < 0,05). Показана эффективность использования для стимуляции неспецифической резистентности к мелиоидозу гетерологичной чумной вакцины EV, однократное введение которой за 1 сут. до заражения защищало 90% мышей от 6 ЛД 50 Burkholderia pseudomallei и 60%-при повышении заражающей дозы возбудителя мелиоидоза до 15 ЛД 50. Такой же уровень защиты от мелиоидоза обеспечивал и 3-дневный курс антибиотикотерапии доксициклином. Сделан вывод о нецелесообразности использования для иммуностимуляции при мелиоидозе туляремийной вакцины ввиду ее высокой остаточной вирулентности и реактогенности.
Melioidosis is a life-threatening infection caused by Burkholderia pseudomallei, an environmental Gram-negative bacterium, inhabitant of moist soils in the tropics and subtropics. There is no licensed vaccine against melioidosis. The main routes of B. pseudomallei infection are percutaneous inoculation, inhalation, or ingestion. Individual cases of vertical, sexual, zoonotic, and nosocomial transmission of melioidosis are described. Risk factors for infection are contact with soil or water (especially during the rainy season). The age over 45, type 2 diabetes, alcoholism, liver disease, chronic lung disease, chronic renal disease, and thalassemia, as well as long-term use of steroids and immunosuppressive therapy, are the main susceptibility factors for melioidosis. Among the affected adult residents of endemic regions, 80% had one or more predisposing factors, among children — about 20%. No significant influence of concomitant diseases on the development of melioidosis in travelers was found. Less than 50% of patients had predisposing factors. The incubation period of melioidosis ranges within 1—21 days; on average, 9 days, in case of sizeable infectious dose, it can be less than one day. There is no post-infectious immunity, and reinfection can occur with a different B. pseudomallei strain after successful treatment. B. pseudomallei is a facultative intracellular pathogen that can invade and multiply inside a wide range of cells, including phagocytic. The acute form of melioidosis is characterized by pneumonia, multiple abscesses, bacteremia, and systemic sepsis. Chronic, subacute, and latent forms are also possible. Antimicrobial therapy is divided into the initial intensive phase and the subsequent eradication phase. B. pseudomallei is resistant to penicillins, first- and second-generation cephalosporins, aminoglycosides, macrolides, chloramphenicol, fluoroquinolones, tetracyclines, trimethoprim, and in some cases to co-trimoxazole, and rarely to ceftazidime. Early diagnosis and appropriate management are crucial in reducing severe complications leading to high mortality, and in preventing disease recurrences. However, there is no pathognomonic melioidosis-specific feature, and the disease is not well known to physicians and microbiologists. The results of serological tests for detection of specific antibodies are ambiguous. The bacterial load of the tested sample limits the detection of antigens. Among the accelerated methods for identifying the causative agent of melioidosis, PCR has the highest sensitivity and specificity. Automated identification using microbiological analyzers generally shows good results, but about 15% of isolates are misidentified. Time-of-flight mass spectrometry with matrix-assisted laser desorption ionization is potentially useful for rapid identification of B. pseudomallei. However, existing databases require optimization by adding the reference spectra for B. pseudomallei.
МИКРОБИОЛОГИЯ 752017, issue 3 кокцидиоидомикоз и гистоплазмоз -инфекци-онные болезни, вызываемые особо опасными ди-морфными грибами II группы патогенности Coccidioides sp. и Histoplasma sp. восприимчивость чело-века к возбудителям этих инфекций считается все-общей. в настоящее время вследствие расширения миграционных потоков, туристических связей и дру-гих возможностей коммуникации населения случаи заболевания кокцидиоидомикозом и гистоплазмозом регистрируют во многих странах мира. присутствие возбудителей особо опасных микозов среди потен-циальных агентов биотерроризма еще более актуа-лизирует проведение исследований, направленных на их индикацию и идентификацию [3]. в связи с Пробл. особо опасных инф. 2017; 3:75-79 целью работы является оценка и диагностической чувствительности и специфичности «набора реагентов. диагностикум эритроцитарный кокцидиоидомикозный и гистоплазмозный иммуноглобулиновый сухой», пред-назначенного для идентификации возбудителей кокцидиоидомикоза и гистоплазмоза в выделенных культурах микромицетов, а также клиническом и биологическом материале с помощью рнга. материалы и методы. с использованием предложенного диагностикума проведено исследование 264 положительных проб (216 проб суспензий микромицетов, 48 проб биологического и клинического материала), содержащих возбудители гисто-плазмоза, кокцидиоидомикоза в концентрации 3,12•10 6 и 1,56•10 6 кл/мл и 128 отрицательных проб, содержащих гетерологичные микроорганизмы в концентрации 5•10 7 кл/мл. в работе использовали пробы биологического ма-териала, искусственно контаминированные данными возбудителями особо опасных микозов, и полученные от биопробных животных с экспериментальной инфекцией. Выводы и результаты. установлено, что диагностиче-ская чувствительность набора реагентов составила не менее 99,0 %, диагностическая специфичность -не менее 98,0 %. воспроизводимость результатов во всех случаях 100 %. полученные результаты указывают на перспек-тивность внедрения разработанного препарата в практику здравоохранения.Ключевые слова: кокцидиоидомикоз, гистоплазмоз, рнга, набор реагентов. Objective of the study was to assess analytical and diagnostic sensitivity and specificity of the "Reagent kit. Erythrocytic coccidioidomycosal and histoplasmosal immunoglobulin dry diagnosticum", designed for identification of causative agents of coccidioidomycosis and histoplasmosis in isolated cultures of micromycetes, as well as in clinical and biological samples using indirect hemagglutination test. Materials and methods. The investigation included 264 positive samples (216 samples of micromycete suspensions, 48 samples of biological and clinical material) containing pathogens of histoplasmosis and coccidioidomycosis concentrated up to 3,12·10 6 and 1,56·10 6 cells∕ml, respectively, and 128 negative samples containing heterologous microorganisms in concentrations equal to 5·10 6 cells/ml. The study was carried out using biological samples that were artificially contaminated with stated pathogens of particularly dangerous mycoses and samples, obtained from ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.