19 research outputs found
Prevention of infections by vaccines and immune modulators
ΠΡΠΊΡΠΈΠ²Π°Π½Π΅ΡΠΎ ΠΈ Π²Π½Π΅Π΄ΡΡΠ²Π°Π½Π΅ΡΠΎ Π½Π° Π²Π°ΠΊΡΠΈΠ½ΠΈΡΠ΅ ΠΈ ΠΈΠΌΡΠ½ΠΎΠΌΠΎΠ΄ΡΠ»Π°ΡΠΎΡΠΈΡΠ΅ Π² ΠΌΠ΅Π΄ΠΈΡΠΈΠ½ΡΠΊΠ°ΡΠ° ΠΏΡΠ°ΠΊΡΠΈΠΊΠ° Π΅ ΠΎΠ³ΡΠΎΠΌΠ½Π° ΠΊΡΠ°ΡΠΊΠ° Π½Π°ΠΏΡΠ΅Π΄ Π² ΠΏΡΠ΅Π΄ΠΎΡΠ²ΡΠ°ΡΡΠ²Π°Π½Π΅ Π½Π° ΠΈΠ½ΡΠ΅ΠΊΡΠΈΠΎΠ·Π½ΠΈΡΠ΅ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ, Π½ΡΠΊΠΎΠΈ ΠΎΡ ΠΊΠΎΠΈΡΠΎ ΡΠ° Π·Π°Π²ΡΡΡΠ²Π°Π»ΠΈ ΡΠ°ΡΠ°Π»Π½ΠΎ ΠΏΡΠΈ ΠΌΠΈΠ½Π°Π»ΠΈΡΠ΅ Π²Π΅ΠΊΠΎΠ²Π΅. Π‘ ΠΏΡΠΎΠ³ΡΠ΅ΡΠ° Π² ΠΌΠ΅Π΄ΠΈΡΠΈΠ½ΡΠΊΠ°ΡΠ° Π½Π°ΡΠΊΠ° Π½Π΅ΠΏΡΠ΅ΠΊΡΡΠ½Π°ΡΠΎ ΡΠ΅ ΡΡΡΠ²ΡΡΡΠ΅Π½ΡΡΠ²Π° ΠΈΠΌΡΠ½ΠΎΠΏΡΠΎΡΠΈΠ»Π°ΠΊΡΠΈΠΊΠ°ΡΠ°, ΠΊΠ°ΡΠΎ ΡΠ΅ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠ²Π°Ρ ΠΏΠΎ-ΠΌΠΎΠ΄Π΅ΡΠ½ΠΈ ΡΠ΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΠΈ Π·Π° ΠΏΠΎ-Π±Π΅Π·ΠΎΠΏΠ°ΡΠ½ΠΈ ΠΈ Π΅ΡΠ΅ΠΊΡΠΈΠ²Π½ΠΈ Π²Π°ΠΊΡΠΈΠ½ΠΈ, ΠΊΠΎΠ΅ΡΠΎ ΠΏΠΎΠ²ΠΈΡΠ°Π²Π° Π·Π΄ΡΠ°Π²Π½ΠΈΡ ΡΡΠ°ΡΡΡ Π½Π° ΠΎΠ±ΡΠ΅ΡΡΠ²ΠΎΡΠΎ, ΠΈΠ·ΡΠ΅Π·Π²Π°Ρ ΡΠΌΡΡΡΠ½ΠΈΡΠ΅ ΠΈ ΠΈΠ½Π²Π°Π»ΠΈΠ΄ΠΈΠ·ΠΈΡΠ°ΡΠΈ ΡΠ΅ΠΆΠΊΠΎ ΠΏΡΠΎΡΠΈΡΠ°ΡΠΈ ΡΠ»ΡΡΠ°ΠΈ, Π½Π°ΠΌΠ°Π»ΡΠ²Π°Ρ ΡΠ°Π·Ρ
ΠΎΠ΄ΠΈΡΠ΅ Π·Π° Π»Π΅ΡΠ΅Π½ΠΈΠ΅. Π¦Π΅Π» Π½Π° ΡΠ°Π·ΠΈ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠΊΠ° Π΅ Π΄Π° ΠΏΡΠ΅Π΄ΡΡΠ°Π²ΠΈ ΠΊΠ»Π°ΡΠΈΡΠΈΠΊΠ°ΡΠΈΡΡΠ° Π½Π° Π²ΠΈΠ΄ΠΎΠ²Π΅ΡΠ΅ Π²Π°ΠΊΡΠΈΠ½ΠΈ ΠΈ ΠΈΠΌΡΠ½ΠΎΠΌΠΎΠ΄ΡΠ»Π°ΡΠΎΡΠΈ, ΠΊΠ°ΠΊΡΠΎ ΠΈ ΡΡΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΠΎ ΡΡΡΡΠΎΡΠ½ΠΈΠ΅ Π½Π° Π΅ΡΠ΅ΠΊΡΠ° ΠΎΡ ΠΏΡΠΈΠ»ΠΎΠΆΠ΅Π½ΠΈΠ΅ΡΠΎ ΠΈΠΌ Π·Π° ΠΏΡΠ΅Π²Π΅Π½ΡΠΈΡ Π½Π° ΠΈΠ½ΡΠ΅ΠΊΡΠΈΠΎΠ·Π½ΠΈ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ. ΠΠ°ΡΠ΅ΡΠΈΠ°Π» ΠΈ ΠΌΠ΅ΡΠΎΠ΄ΠΈ: Π‘ΡΠ±ΡΠ°Π½Π° Π΅ Π°ΠΊΡΡΠ°Π»Π½Π° ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΎΡ Π½Π°ΡΡΠ½ΠΈ ΠΈΠ·ΡΠΎΡΠ½ΠΈΡΠΈ Π½Π° ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΏΠΎ ΡΠ΅ΠΌΠ°ΡΠ° Π²Π°ΠΊΡΠΈΠ½ΠΎΠΏΡΠΎΡΠΈΠ»Π°ΠΊΡΠΈΠΊΠ° ΠΈ ΠΈΠΌΡΠ½ΠΎΠΌΠΎΠ΄ΡΠ»Π°ΡΠΎΡΠΈ. Π’Ρ Π΅ Π°Π½Π°Π»ΠΈΠ·ΠΈΡΠ°Π½Π°, ΡΠΈΡΡΠ΅ΠΌΠ°ΡΠΈΡΠ½ΠΎ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π΅Π½Π° ΠΈ ΠΈΠ»ΡΡΡΡΠΈΡΠ°Π½Π° Ρ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄ΡΡΠΈ Π³ΡΠ°ΡΠΈΠΊΠΈ. Π Π΅Π·ΡΠ»ΡΠ°ΡΠΈ ΠΈ ΠΎΠ±ΡΡΠΆΠ΄Π°Π½Π΅: ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ Π΅ Π·Π½Π°ΡΠ΅Π½ΠΈΠ΅ΡΠΎ Π½Π° Π²Π°ΠΊΡΠΈΠ½ΠΈΡΠ΅ ΠΈ ΠΈΠΌΡΠ½ΠΎΠΌΠΎΠ΄ΡΠ»Π°ΡΠΎΡΠΈΡΠ΅ Π·Π° ΠΎΠ³ΡΠ°Π½ΠΈΡΠ°Π²Π°Π½Π΅ Π½Π° ΡΠ΅Π΄ΠΈΡΠ° ΠΎΠΏΠ°ΡΠ½ΠΈ Π²ΠΈΡΡΡΠ½ΠΈ ΠΈ Π±Π°ΠΊΡΠ΅ΡΠΈΠ°Π»Π½ΠΈ ΠΈΠ½ΡΠ΅ΠΊΡΠΈΠΈ, Π½Π°ΠΏΡ. ΡΡΠΏΠ΅ΡΠ½Π°ΡΠ° Π΅ΡΠ°Π΄ΠΈΠΊΠ°ΡΠΈΡ Π½Π° Π²Π°ΡΠΈΠΎΠ»Π°. ΠΡΠ΅Π΄ΡΡΠ°Π²Π΅Π½Π° Π΅ ΡΡΠ²ΡΠ΅ΠΌΠ΅Π½Π½Π° ΠΊΠ»Π°ΡΠΈΡΠΈΠΊΠ°ΡΠΈΡ Π½Π° ΡΠ΅Π·ΠΈ ΡΡΠ΅Π΄ΡΡΠ²Π° Π·Π° ΠΈΠΌΡΠ½ΠΎΠΏΡΠΎΡΠΈΠ»Π°ΠΊΡΠΈΠΊΠ°. ΠΠ·Π±ΡΠΎΠ΅Π½ΠΈ ΡΠ° ΠΈΠ·ΠΏΠΎΠ»Π·Π²Π°Π½ΠΈΡΠ΅ ΠΏΠΎΠ½Π°ΡΡΠΎΡΡΠ΅ΠΌ Π² ΠΡΠ»Π³Π°ΡΠΈΡ Π²Π°ΠΊΡΠΈΠ½ΠΈ ΠΈ ΠΈΠΌΡΠ½ΠΎΠΌΠΎΠ΄ΡΠ»Π°ΡΠΎΡΠΈ, ΡΠ°Π·Π³Π»Π΅Π΄Π°Π½ Π΅ Π°ΠΊΡΡΠ°Π»Π½ΠΈΡΡ ΠΊΡΠΌ ΠΌΠΎΠΌΠ΅Π½ΡΠ° Π½Π° ΠΏΡΠΎΡΡΠ²Π°Π½Π΅ΡΠΎ ΠΈΠΌΡΠ½ΠΈΠ·Π°ΡΠΈΠΎΠ½Π΅Π½ ΠΊΠ°Π»Π΅Π½Π΄Π°Ρ. ΠΠ±Π΅ΠΊΡΠΈΠ²Π½ΠΎ ΡΠ° ΡΠ°Π·Π³Π»Π΅Π΄Π°Π½ΠΈ ΠΊΠ°ΠΊΡΠΎ ΠΏΠΎΠ»Π΅Π·Π½ΠΈΡΠ΅ Π΅ΡΠ΅ΠΊΡΠΈ ΠΎΡ ΠΏΡΠΈΠ»ΠΎΠΆΠ΅Π½ΠΈΠ΅ΡΠΎ ΠΈΠΌ, ΡΠ°ΠΊΠ° ΠΈ Π½ΡΠΊΠΎΠΈ Π½Π΅ΠΆΠ΅Π»Π°Π½ΠΈ, ΡΡΡΠ°Π½ΠΈΡΠ½ΠΈ Π΅ΡΠ΅ΠΊΡΠΈ. ΠΡΠΎΡΠ»Π΅Π΄Π΅Π½ΠΈ ΡΠ° ΡΠ΅Π½Π΄Π΅Π½ΡΠΈΠΈ Π·Π° Π±ΡΠ΄Π΅ΡΠΎΡΠΎ ΡΠ°Π·Π²ΠΈΡΠΈΠ΅ Π½Π° ΠΈΠΌΡΠ½ΠΎΠΏΡΠΎΡΠΈΠ»Π°ΠΊΡΠΈΠΊΠ°ΡΠ° Π² ΠΡΠ»Π³Π°ΡΠΈΡ ΠΈ Π² ΡΠ²Π΅ΡΠ°. ΠΠ·Π²ΠΎΠ΄ΠΈ: ΠΡΠ΅ΠΊΡΡΡ ΠΎΡ ΠΏΡΠΈΠ»Π°Π³Π°Π½Π΅ΡΠΎ Π½Π° Π²Π°ΠΊΡΠΈΠ½ΠΈ ΠΈ ΠΈΠΌΡΠ½ΠΎΠΌΠΎΠ΄ΡΠ»ΠΈΡΠ°ΡΠΈ ΡΡΠ΅Π΄ΡΡΠ²Π° Π½Π΅ ΡΠ°ΠΌΠΎ Π·Π° ΠΏΡΠΎΡΠΈΠ»Π°ΠΊΡΠΈΠΊΠ°, Π½ΠΎ ΠΈ ΠΏΡΠΈ ΡΠ΅ΡΠ°ΠΏΠΈΡ Π½Π° Π½ΡΠΊΠΎΠΈ ΠΈΠ½ΡΠ΅ΠΊΡΠΈΠΎΠ·Π½ΠΈ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ ΠΏΡΠ΅Π· ΠΏΠΎΡΠ»Π΅Π΄Π½ΠΈΡΠ΅ Π΄Π²Π΅ ΡΡΠΎΠ»Π΅ΡΠΈΡ Π΅ Π΄ΠΎΠΊΠ°Π·Π°Π½ Π² ΠΌΠ΅Π΄ΠΈΡΠΈΠ½ΡΠΊΠ°ΡΠ° Π½Π°ΡΠΊΠ° ΠΈ Π² ΠΏΡΠ°ΠΊΡΠΈΠΊΠ°ΡΠ°. Π‘ΠΈΠ»Π½ΠΎ ΠΎΠ³ΡΠ°Π½ΠΈΡΠ΅Π½ΠΈ ΠΈ ΠΎΠ±Π»Π΅ΠΊΡΠ΅Π½ΠΈ ΠΏΠΎ ΠΏΡΠΎΡΠΈΡΠ°Π½Π΅ ΡΠ° ΠΈΠ½ΡΠ΅ΠΊΡΠΈΠΈ, ΠΏΡΠΈΡΠΈΠ½Π΅Π½ΠΈ ΠΎΡ ΡΠΈΠ»Π½ΠΎ ΠΏΠ°ΡΠΎΠ³Π΅Π½Π½ΠΈ Π²ΠΈΡΡΡΠΈ ΠΈ Π±Π°ΠΊΡΠ΅ΡΠΈΠΈ. ΠΠ°Π±Π»ΡΠ΄Π°Π²Π° ΡΠ΅ Π΅ΡΠ΅ΠΊΡ ΠΈ ΡΡΠ΅ΡΡ Π½ΡΠΊΠΎΠΈ ΡΡΠΌΠΎΡΠ½ΠΈ ΠΎΠ±ΡΠ°Π·ΡΠ²Π°Π½ΠΈΡ. ΠΠ° ΠΏΠΎΠ²ΠΈΡΠ°Π²Π°Π½Π΅ Π½Π° Π΅ΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡΠ° ΠΎΡ ΠΏΡΠΈΠ»Π°Π³Π°Π½Π΅ΡΠΎ ΠΈΠΌ, Π² ΡΠ²Π΅ΡΠΎΠ²Π΅Π½ ΠΌΠ°ΡΠ°Π±, ΡΠ΅ ΠΈΠ·ΠΈΡΠΊΠ²Π°Ρ ΠΏΠ»Π°Π½ΠΈΡΠ°Π½ΠΈ ΠΈ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½ΠΈΡΠ°Π½ΠΈ ΡΡΠΈΠ»ΠΈΡ Π½Π° Π·Π΄ΡΠ°Π²Π½ΠΈΡΠ΅ ΠΈΠ½ΡΡΠΈΡΡΡΠΈΠΈ Π² ΠΎΡΠ΄Π΅Π»Π½ΠΈΡΠ΅ ΡΡΡΠ°Π½ΠΈ, a ΡΠΎΠ²Π° ΡΠ΅ ΠΏΠΎΡΡΠΈΠ³Π° Π±Π»Π°Π³ΠΎΠ΄Π°ΡΠ΅Π½ΠΈΠ΅ Π½Π° ΠΎΠ±Π΅Π΄ΠΈΠ½ΡΠ²Π°ΡΠ°ΡΠ° Π΄Π΅ΠΉΠ½ΠΎΡΡ Π½Π° Π‘ΠΠ.Introduction: The discovery and implementation of vaccines and immune modulators in medical practice is a huge step forward towards the prevention of infectious diseases, some of which have lead to a fatal outcome during the past centuries. Immune prophylaxis has been continuously improving along with the progress in medical sciences by developing more advanced technologies for safer and more effective vaccines, which increases the health status of the population of our society. The deaths and severely debilitating cases have disappeared and the cost of treatment has been reduced. Aim: The aim of this work is to present the classification of vaccines and immune modulators, as well as the current state of the effect of their application on the prevention of infectious diseases. Materials and Methods: Current information from scientific sources on the prevention by vaccines and immune modulators has been accumulated. It has been analyzed, systematically presented and illustrated by appropriate graphics. Results and Discussion: The importance of vaccines and immune modulators for limiting a number of dangerous viral and bacterial infections, such as successful eradication of smallpox, is shown. Contemporary classification of these agents for immune prophylaxis is presented. The vaccines and immune modulators used nowadays in Bulgaria are listed, the up-to-date immunization calendar is considered. Both the beneficial effects of their application and some undesirable side effects are objectively presented. Trends for the future development of immune prevention in Bulgaria and in the world are traced.Conclusions: The effect of application of vaccines and immune modulating agents in medical science and practice has been proved to be useful not only for prophylaxis but also for therapy of some infectious diseases during the last two centuries. Very limited and relieved are infections caused by strong pathogenic viruses and bacteria. Also, an effect against some tumor formations has been established. To increase the effectiveness of their implementation worldwide, planned and coordinated efforts of healthcare institutions in all the countries are required, and this is achieved thanks to the unifying activity of WHO
Investigation of multidrug-resistant Helicobacter pylori in pediatric patients: A Bulgarian study and literature data
Antibiotic resistance of Helicobacter pylori strains from 106 symptomatic children was evaluated according to EUCAST breakpoints and rate of multidrug resistance (MDR) was analyzed. Overall resistance rates were amoxicillin 7.5%, metronidazole 25.5%, clarithromycin 34.0% and ciprofloxacin 14.1%. There were no significant differences in resistance rates according to patients' age (2-6 and 7-18 years) and sex. Combined resistance rate was 19.8%, including double, triple, and quadruple resistance in 13.2% (14 strains), 5.7% (6) and 0.9% (1) of the strains, respectively. MDR was found in 5.9% (5/84) of the children with gastritis and in two of the four children with celiac disease. The MDR was present in three children aged 4-6 years and in four children aged 10-17 years. The total MDR rate (6.6%) in Bulgarian children in 2012-2021 was higher than those in other studies based on EUCAST breakpoints such as those in pediatric patients in Slovenia in 2011-2014 (3.8%), Lithuania in 2013-2015 (0%) and Spain in 2014-2019 (0%), although being lower than those (20.7% in the untreated and 47.0% in the treated children) in China in 2019. In brief, it is of concern that MDR can strongly limit the choice of H. pylori therapy of one out of fifteen Bulgarian children and that overall resistance to both metro-nidazole and clarithromycin can hinder the treatment of 15.1% of the pediatric patients. Susceptibility-guided tailored eradication therapy of H. pylori infection should be more frequently implemented in the symptomatic children to avoid risks of both the infection itself and multiple antibiotic treatments
Molecular epidemiology, virulence and antimicrobial resistance of Bulgarian methicillin resistant Staphylococcus aureus isolates
Background: Severe infections of virulent methicillin-resistant Staphylococcus aureus (MRSA) are a serious health problem. The present study aimed to investigate clonal spread, virulence and antimi-crobial resistance rates of Bulgarian MRSA isolates in 2016-2020. Methods: Molecular identification and mecA gene detection were performed with PCR. Clonal relatedness was evaluated by RAPD PCR and MLST. MRSA epidemiology, virulence and resistance patterns were investigated by PCR. Results: All 27 isolates were identified as S. aureus and were mecA positive, and all were susceptible to linezolid, tigecycline and vancomycin. The toxin genes hlg (in 92.6% of isolates), seb (77.8%), sei (77.8%), seh (59.3%), sej (55.6%), and seg (48.1%), were frequently found among the isolates. Epidemiological typing by RAPD identified 4 clones (16 isolates) and 11 were with a unique profile. MLST analysis of the same MRSA isolates showed five MLST clonal complexes and 11 ST types, including CC5 (33.3%) (ST5, ST221, ST4776), CC8 (22.2%) (ST8, ST239, ST72), CC15 (ST582), CC22 (14.8%) (ST217, ST5417), CC30 (ST30) CC398 (ST398), and CC59 (ST59). The isolates from CC5 showed higher virulence po-tential and almost all were macrolide resistant (ermB or ermC positive). CC8 isolates showed higher level of resistance. Conclusion: To the best of our knowledge, this study is the first describing the clonal spreading of Bulgarian MRSA and the association with their virulence and resistance determinants. Monitoring of MRSA epidemiology, resistance and virulence profile can lead to better prevention and faster therapeutic choice in cases of severe infections
First detection of a colistin-resistant Klebsiella aerogenes isolate from a critically ill patient with septic shock in Bulgaria
Colistin is considered as the last-line antibiotic for the treatment of infections caused by extensively drug-resistant Gram-negative pathogens belonging to the ESKAPE (Enterococcus faecium, Staphylo-coccus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enter-obacter species) group. The present study aimed to explore the colistin resistance mechanisms of a Klebsiella aerogenes (formerly Enterobacter aerogenes) isolate (Kae1177-1bg) obtained from a Bulgarian critically ill patient with septic shock in 2020. Antimicrobial susceptibility testing and whole-genome sequencing using DNA nanoball technology were performed. The resulting read pairs were used for draft genome assembly, MLST analysis and mutation screening in the pmrA/B, phoP/Q, and mgrB genes. Kae1177-1bg demonstrated high-level resistance to colistin, resistance to 3rd generation cepha-losporins and susceptibility to all other antibiotics tested. In our strain a CMY-2-type class C cepha-losporinase was the only beta-lactamase identified. No mobile colistin resistance (mcr) genes were detected. A total of three missense variants in the genes for the two-component PmrA/PmrB system were identified. Two of them were located in the pmrB (pR57K and pN275K) and one in the pmrA gene (pL162M). The pN275K variant emerged as the most likely cause for colistin resistance because it affected a highly conservative position and was the only nonconservative amino acid substitution. In conclusion, to the best of our knowledge, this is the first documented clinical case of a high-level colistin-resistant K. aerogenes in Bulgaria and the first identification of the nonconservative amino acid substitution pN275K worldwide. Colistin-resistant Gram-negative pathogens of ESKAPE group are serious threat to public health and should be subjected to infection control stewardship practices
Association of pili with widespread multidrug- resistant genetic lineages of non-invasive pediatric Streptococcus pneumoniae isolates
The study aimed to evaluate the presence of pili in non-invasive pediatric pneumococcal isolates and to elucidate possible links with genetic lineages, serotypes, and antimicrobial resistance. We examined 147 Streptococcus pneumoniae isolates from children with respiratory tract infections and acute otitis media. Serotyping was performed by latex agglutination and capsule swelling reaction. Serogroup 6 was subjected to PCR-serotyping. Minimum inhibitory concentrations were determined according to EUCAST breakpoints. PCRs for rlrA and pitB genes were performed to detect a presence of type 1 and type 2 pili. MLST was conducted to define the clonal structure of the piliated strains. Almost all children (96.5%) were vaccinated with the pneumococcal conjugate vaccine PCV10. We detected 76.8% non-PCV10 - serotypes (NVTs) and 14.3% PCV10 serotypes. The predominant serotypes were NVTs: 19A (14.3%), 6C (12.2%), 3 (9.5%), 15A (7.5%) and 6A (6.8%). PI-1 was detected among 10.9% non-PCV10 serotypes 6A, 6C, and 19A and 6.1% PCV10 serotypes 19F and 23F. Type 2 pili were not found in the studied population. High levels of antimicrobial nonsusceptibility to erythromycin (58.5%), oral penicillin (55.8%), clindamycin (46.9%), trimethoprim-sulfamethoxazole (45.6%), tetracycline (39.5%) and ceftriaxone (16.3%) were revealed. The multidrug-resistant strains (MDR) were 55.1%. MLST represented 18 STs and three CCs among the piliated pneumococci: CC386, CC320, and CC81. More than half of the piliated strains (56.0%) belonged to successfully circulating international clones. PI-1 was associated mainly with MDR 6A, 6C, 19A, 19F, and 23F isolates from the widespread CC386, CC320, and CC81
Molecular-genetic Method for Fast Direct Detection of Staphylococcus Aureus and Methicillin Resistance in Blood Cultures and Punctures
Background: Invasive infections caused by methicillin resistant Staphylococcus aureus and coagulase-negative staphylococci (MRSA/MRSCoN) require fast, adequate treatment.Β The aim of this study was to develop a faster protocol for direct detection of MRSA/MRSCoN in blood cultures and in abscess punctures based on mecA and species specific identification of S. aureus by polymerase-chain reaction (PCR).Materials and methods: We examined 77 growth-positive BACTEC blood cultures and 50 abscess punctures by routine microbiological assay and simultaneous PCR detection of MRSA/MRSCoN. The speciο¬city of the PCR was evaluated by using DNA from another 15 microbial species for negative controls. We determined the minimum inhibitory concentration (MIC) of oxacillin, vancomycin, tigecycline, linezolid, levofloxacin, clindamycin, and erythromycin against the S. aureus isolates using the E-test.Β Results: In the blood cultures, the two methods detected 39.3% of MRSA, and 93.9% of MRCoNS. In the punctures, the PCR assay identified 20.9% of MRSA and 79.2% of MSSA. In the puncture cases, there were three PCR MRSA positive and culture negative samples. Screening for susceptibility to 14 antimicrobial agents demonstrated significantly higher (p<0.05) methicillin resistance in blood culture isolates than in the puncture ones (39.3% and 20.0%, respectively).Β Conclusion: The new PCR protocol was very fast and specific. It was more sensitive in detecting MRSA from abscess punctures than the routine microbiological techniques. This protocol will speed up the right choice of empirical therapy, which is extremely important for saving patientsβ lives
Molecular-genetic Method for Fast Direct Detection of Staphylococcus Aureus and Methicillin Resistance in Blood Cultures and Punctures
Background: Invasive infections caused by methicillin resistant Staphylococcus aureus and coagulase-negative staphylococci (MRSA/MRSCoN) require fast, adequate treatment.Β The aim of this study was to develop a faster protocol for direct detection of MRSA/MRSCoN in blood cultures and in abscess punctures based on mecA and species specific identification of S. aureus by polymerase-chain reaction (PCR).Materials and methods: We examined 77 growth-positive BACTEC blood cultures and 50 abscess punctures by routine microbiological assay and simultaneous PCR detection of MRSA/MRSCoN. The speciο¬city of the PCR was evaluated by using DNA from another 15 microbial species for negative controls. We determined the minimum inhibitory concentration (MIC) of oxacillin, vancomycin, tigecycline, linezolid, levofloxacin, clindamycin, and erythromycin against the S. aureus isolates using the E-test.Β Results: In the blood cultures, the two methods detected 39.3% of MRSA, and 93.9% of MRCoNS. In the punctures, the PCR assay identified 20.9% of MRSA and 79.2% of MSSA. In the puncture cases, there were three PCR MRSA positive and culture negative samples. Screening for susceptibility to 14 antimicrobial agents demonstrated significantly higher (p<0.05) methicillin resistance in blood culture isolates than in the puncture ones (39.3% and 20.0%, respectively).Β Conclusion: The new PCR protocol was very fast and specific. It was more sensitive in detecting MRSA from abscess punctures than the routine microbiological techniques. This protocol will speed up the right choice of empirical therapy, which is extremely important for saving patientsβ lives
Relationship between MLSB resistance and the prevalent virulence genotypes among Bulgarian Staphylococcus aureus isolates
The aim of this study was to investigate the rate of resistance to macrolide-lincosamide-streptogramin B (MLSB) antibiotics, the mechanisms underlying this resistance and to evaluate their relationship with virulence genes profiles of 435 Bulgarian clinical isolates Staphylococcus aureus. The highest resistance was observed to penicillin (96.09%), followed by resistance to erythromycin and clindamycin (34.02 and 22.76%, respectively). Of the tested clinical strains of S. aureus, 96.09% contained the blaZ gene associated with penicillin resistance and 11.03%, the mecA gene responsible for methicillin resistance. The most prevalent were the erm genotypes associated with the presence mainly of ermA and ermC genes followed by ermB. The frequency rates of these genes, alone or in combinations were ermA 41.89%, ermB 27.70%, ermC 43.99%. The majority of Bulgarian macrolide resistant S. aureus exhibited cMLS phenotype, in 58.78% (P 5 0.0036). The following virulence genotypes were present significantly more often in the macrolide resistant S. aureus isolates among the studied ones: hlg; hlg,seb; hlg,seb,sec; hlg,seb,seh; hlg,sec; hlg,sec,sei; hlg,sec,sei; hlg,sei; hlg,sei,sej; hlg,sej. This survey found correlation between the virulence profiles with a small number of genes and macrolide resistance among Bulgarian clinical S. aureus isolates, in contrast to sensitive strains, which possessed profiles predominantly with multiple genes
Geographic distribution of antibiotic resistance of Helicobacter pylori: A study in Bulgaria
Prevalence of antibiotic resistant Helicobacter pylori was compared between 50 patients living outside the capital city and 50 matched pairs of capital city residents (CCRs). H. pylori isolates from 2018 to 2022 were included. Resistance rates in CCRs and those living elsewhere were 4.0 and 6.0% to amoxicillin, 48.0 and 42.0% to metronidazole, 30 and 30% to clarithromycin, and 4.0 and 4.0% to tetracycline, respectively. Levofloxacin resistance was higher (38.0%) in the capital city vs 20.0% (P = 0.047) in the country. Odd ratio for levofloxacin resistance between pair-matched groups was 2.45 (95% CI, OR 1.0-6.02, P value = 0.05) and relative risk for fluoroquinolone resistance was 1.90 (95% CI for RR 0.98-3.67) for CCRs vs residents in other regions. Resistance rates to levofloxacin and clarithromycin were worryingly high in our study, most probably due to the high quinolone consumption (2.86 DDD/day in 2017) in Bulgaria and the increase in macrolide, lincosamide and streptogramin consumption, especially of azithromycin, by >42% with the start of COVID-19 pandemic. Briefly, antibiotic resistance of H. pylori has a dynamic change, and it can display different patterns in certain geographic regions. The results imply that antibiotic consumption should be carefully controlled and unjustified use of levofloxacin should be restricted, especially in some large cities. Antibiotic policy should be further strengthened and regular monitoring of resistance in various geographic regions is needed for treatment optimization
Evolution of <i>Helicobacter pylori</i> Resistance to Antibiotics: A Topic of Increasing Concern
Antibiotic resistance among Helicobacter pylori strains is the major cause of eradication failure. Resistance prevalence is dynamic and can greatly vary among countries over the years. We revealed H. pylori resistance trends for five antibiotics in 14 countries through articles predominantly published in 2018β2022, since the latest data can best show the most recent trends in resistance evolution. Amoxicillin resistance generally exhibited no evolution, yet it increased in Bulgaria, Iran, China, and Vietnam. Metronidazole resistance exhibited different trends, including an increase, a decrease and no evolution in six, three, and five studies, respectively. Clarithromycin resistance increased in Australia, Belgium, Bulgaria, Italy, Iran, and Taiwan, but remained stable in France, Spain, Russia, China, Chile, and Colombia. Tetracycline resistance was low and stable except in Iran. Levofloxacin resistance increased in four European and six other countries/regions, without significant increases in France, Spain, and Chile. In Chile, triple resistance also increased. In countries such as France and Spain, resistance to most antibiotics was stabilized, while in Bulgaria, Belgium, Iran and Taiwan, resistance to three or more agents was reported. Use of non-recommended regimens, national antibiotic consumption, patientβs compliance, host factors, strain virulence, migrations, and azithromycin overuse during the COVID-19 pandemic can influence resistance evolution. New drugs, eradication regimens and diagnostic methods, such as next-generation sequencing can improve H. pylori infection control