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1.
Lett Appl Microbiol ; 77(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38794899

RESUMEN

Non-antibiotic adjuncts may improve Helicobacter pylori infection control. Our aim was to emphasize curcumin benefits in controlling H. pylori infection. We discussed publications in English mostly published since 2020 using keyword search. Curcumin is the main bioactive substance in turmeric. Curcumin inhibited H. pylori growth, urease activity, three cag genes, and biofilms through dose- and strain-dependent activities. Curcumin also displayed numerous anticancer activities such as apoptosis induction, anti-inflammatory and anti-angiogenic effects, caspase-3 upregulation, Bax protein enhancement, p53 gene activation, and chemosensitization. Supplementing triple regimens, the agent increased H. pylori eradication success in three Iranian studies. Bioavailability was improved by liposomal preparations, lipid conjugates, electrospray-encapsulation, and nano-complexation with proteins. The agent was safe at doses of 0.5->4 g daily, the most common (in 16% of the users) adverse effect being gastrointestinal upset. Notably, curcumin favorably influences the intestinal microbiota and inhibits Clostridioides difficile. Previous reports showed the inhibitory effect of curcumin on H pylori growth. Curcumin may become an additive in the therapy of H. pylori infection, an adjunct for gastric cancer control, and an agent beneficial to the intestinal microbiota. Further examination is necessary to determine its optimal dosage, synergy with antibiotics, supplementation to various eradication regimens, and prophylactic potential.


Asunto(s)
Antibacterianos , Curcuma , Curcumina , Infecciones por Helicobacter , Helicobacter pylori , Curcumina/farmacología , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/genética , Humanos , Antibacterianos/farmacología , Microbioma Gastrointestinal/efectos de los fármacos
2.
Diagn Microbiol Infect Dis ; 107(4): 116073, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37717293

RESUMEN

The aim of the study was to evaluate the frequency and characteristics of mixed (multiple-genotype) Helicobacter pylori infections (MGIs) in 155 Bulgarian symptomatic patients (21 children and 134 adults). MGIs were common (36.1%), including double-strain (34.8%) and triple-strain infections (1.3%). None of the 8 ulcer patients harbored multiple subtypes. We detected 18 multiple allelic combinations, of which the most frequent subtypes (17.4%) were vacA s1as2 and vacA s1cs2. The 2 patients with triple-strain infections had vacA s1bs1cs2i1i2/iceA1A2 and vacA s1as1cs2 subtypes. They were both adult men with chronic gastritis and both were examined in 2022. The prevalence of MGIs (51.7%) was 2-fold higher in 2020 to 2022 than in 2015 to 2019 (26.3%). Putative factors for the increase may be the patient's characteristics and COVID-19 pandemic-associated factors. MGI rates corresponded to the high infection seroprevalence (72.4% in 2011) in Bulgaria. The evolution and clinical importance of mixed H. pylori infections merit extensive evaluation.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Adulto , Masculino , Niño , Humanos , Proteínas Bacterianas/genética , Antígenos Bacterianos/genética , Helicobacter pylori/genética , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/complicaciones , Bulgaria/epidemiología , Pandemias , Estudios Seroepidemiológicos , Genotipo
3.
Anaerobe ; 81: 102714, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37349047

RESUMEN

With the buildup of new research data, newer associations between anaerobic bacteria and diseases/conditions were evaluated. The aim of the mini-review was to draw attention and to encourage further multidisciplinary studies of the associations. We considered microbiome-disease correlations such as a decrease of fecal Faecalibacterium prausnitzii abundance in inflammatory bowel disease (IBD) and IBD recurrence, suggesting that F. prausnitzii could be a good biomarker for IBD. A link of subgingival Porphyromonas gingivalis with cardiovascular diseases was reported. Decreased Roseburia abundance was observed in the gut of Alzheimer's and Parkinson's disease patients. Akkermansia muciniphila was found to improve adipose/glucose metabolism, however, its intestinal abundance was observed in neurodegenerative diseases as well. Severe Clostridioides difficile infections have been reported in neonates and young children. Carcinogenic potential of anaerobes has been suggested. Fusobacterium nucleatum was implicated in the development of oral and colorectal cancer, Porphyromonas gingivalis and Tannerella forsythia were linked to esophageal cancer and Cutibacterium acnes subsp. defendens was associated with prostate cancer. However, there are some controversies about the results. In a Swedish longitudinal study, neither P. gingivalis nor T. forsythia exhibited oncogenic potential. The present data can enrich knowledge of anaerobic bacteria and their multifaceted significance for health and disease and can draw future research directions. However, more studies on large numbers of patients over prolonged periods are needed, taking into account the possible changes in the microbiota over time.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Microbiota , Enfermedades no Transmisibles , Masculino , Niño , Recién Nacido , Humanos , Preescolar , Bacterias Anaerobias , Estudios Longitudinales , Enfermedades Inflamatorias del Intestino/microbiología , Porphyromonas gingivalis
4.
Acta Microbiol Immunol Hung ; 70(1): 79-83, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36640264

RESUMEN

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.


Asunto(s)
COVID-19 , Infecciones por Helicobacter , Helicobacter pylori , Humanos , Claritromicina , Levofloxacino , Infecciones por Helicobacter/epidemiología , Bulgaria , Pandemias , Farmacorresistencia Bacteriana , COVID-19/epidemiología , Antibacterianos/farmacología , Amoxicilina , Metronidazol , Pruebas de Sensibilidad Microbiana
5.
Anaerobe ; 77: 102509, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34990817

RESUMEN

Anaerobic cocci are common anaerobic isolates. Numerous genera of anaerobic cocci have been reported in both urinary tract microbiota, mainly of females, and in cases of urinary tract infections (UTIs), predominantly in patients with comorbidities, when no facultatively anaerobic bacteria were detected from the urine samples. UTIs caused by anaerobic cocci have been reported in >7% in some studies. As the routine diagnostic methods may be insufficient to detect and identify the anaerobic cocci in patients with UTIs, enhanced quantitative urine culture (EQUC) can give better results. EQUC is performed by plating urine samples onto different media to be incubated in both aerobic and anaerobic conditions with a prolonged incubation time. Other newer methods such as 16S rRNA gene sequencing, qualitative PCR and Next Generation Sequencing can also be considered. Anaerobic cocci such as Peptoniphilus, Parvimonas, Anaerococcus and Finegoldia spp. were found in patients with bacteremia of urinary source. A fatal outcome has been reported in a diabetic patient with emphysematous pyelonephritis caused by Finegoldia magna and Candida parapsilosis due to a delay in seeking hospital care during the COVID-19 pandemic. In specific cases such as of chronic infections, immunosuppression, comorbidity, advanced age, following urological tract manipulations and negative culture results for usual uropathogens, it may be advisable to use suprapubic aspiration cultured in both aerobic and anaerobic condition or EQUC using media which support the relative slow growing anaerobic cocci as well.


Asunto(s)
COVID-19 , Infecciones Urinarias , Femenino , Humanos , Bacterias Anaerobias/genética , ARN Ribosómico 16S/genética , Anaerobiosis , Pandemias , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/microbiología
6.
Anaerobe ; 62: 102150, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31987991

RESUMEN

The aim of the study was to comparatively assess delafloxacin and levofloxacin activities against 96 anaerobic and some microaerophilic isolates. Delafloxacin minimal inhibitory concentrations (MICs) were strikingly lower than those of levofloxacin. Delafloxacin MIC90 against clostridia, other Gram-positive rods, anaerobic/microaerophilic cocci and Gram-negative rods were 0.75, 0.032, 0.38 and 0.5 µg/mL, respectively. The highest (≥4 µg/mL) MICs of the newer fluoroquinolone were found in only 4.2% of isolates versus 46.9% by levofloxacin. The present results and the potency in acidic conditions showed delafloxacin advantages over levofloxacin in terms of usefulness for treatment of mixed anaerobic-aerobic infections and activity against Clostridioides (Clostridium) difficile.


Asunto(s)
Antibacterianos/farmacología , Bacterias Anaerobias/efectos de los fármacos , Fluoroquinolonas/farmacología , Levofloxacino/farmacología , Humanos , Pruebas de Sensibilidad Microbiana
7.
Diagn Microbiol Infect Dis ; 94(4): 334-336, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30871741

RESUMEN

Two-year Clostridioides (Clostridium) difficile recurrences in a boy with ulcerative colitis are described. Isolates were toxin A/B positive and nonhypervirulent, and resistotypes of 2017 isolates differed from those in 2016, suggesting a reinfection, later confirmed by multilocus sequence typing (ST49 and ST92, respectively). Resistotypes may show the need of genotypic analysis.


Asunto(s)
Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/diagnóstico , Colitis Ulcerosa/complicaciones , Adolescente , Antibacterianos/uso terapéutico , Técnicas de Tipificación Bacteriana , Clostridioides difficile/clasificación , Infecciones por Clostridium/tratamiento farmacológico , Colitis Ulcerosa/microbiología , Heces/microbiología , Humanos , Masculino , Tipificación de Secuencias Multilocus , Recurrencia , Vancomicina/uso terapéutico
8.
Acta Microbiol Immunol Hung ; 66(2): 255-260, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30585499

RESUMEN

Helicobacter pylori positivity was assessed among 656 symptomatic children in 2010-2017. Overall infection prevalence was 24.5% and a significantly higher rate was detected in girls (28.5%) compared to boys (20.0%). Moreover, in children with duodenal ulcer, H. pylori prevalence was higher (47.4%) compared with the rest (23.9%). On the contrary, the infection was detected 1.9-fold less frequently in patients with GERD (14.5%) compared with the other (27.0%) patients and 2.1-fold less often in the presence of duodenogastric reflux (bile) reflux (13.0%) compared with the absence of the reflux (27.0%). No significant difference was observed between the younger (aged ≤7 years, 20.0%) and the older (aged 8-18 years, 25.5%) patients. H. pylori infection rate in Bulgarian pediatric patients between 2010 and 2017 was 2.5-fold lower than that in 1996-2006. In conclusion, H. pylori infection is still an important concern for Bulgarian children, although having decreased by about 1.8%/yearly over 21 years. This study reveals the importance of H. pylori diagnostics even in the youngest symptomatic children and demonstrates an inverse association between either GERD or bile reflux and H. pylori infection.


Asunto(s)
Úlcera Duodenal/microbiología , Reflujo Gastroesofágico/microbiología , Infecciones por Helicobacter/epidemiología , Adolescente , Bulgaria/epidemiología , Niño , Preescolar , Femenino , Infecciones por Helicobacter/microbiología , Helicobacter pylori/fisiología , Humanos , Lactante , Masculino , Prevalencia , Factores Sexuales
9.
Infect Genet Evol ; 59: 167-171, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29427761

RESUMEN

One of the most important virulence factors of H. pylori is the intact cagPAI. The aim of the present study is to investigate cagPAI intactness among Bulgarian H. pylori isolates, its associations with clinical outcomes and vacA alleles, and to evaluate the significance of individual cagPAI genes. MATERIAL AND METHODS: Totally, 156 isolates from 156 patients with endoscopic findings for duodenal or gastric ulcer (33 subjects), non-ulcer disease (121) and other diseases, such as Crohn's disease and hepatitis (2) were tested. Polymerase chain reaction (PCR) was used to detect 14 essential cagPAI genes, including cagA, as well as vacA s, i and m alleles. RESULTS: CagA positive were 81.4% of all H. pylori isolates. Intact cagPAI was found in 64.1% of the all isolates, 16.7% and 19.2% showed complete and partial cagPAI absence, respectively. The prevalence of all cagPAI genes and intact cagPAI was significantly higher in isolates from ulcer patients compared with those from non-ulcer patients (p = 0.001). The most frequently missing genes among the isolates with partially deleted cagPAIs were cagE or/and cagY (28 of 30 isolates). Overall prevalence of vacA s1a allele was 80.1% and that of vacA i1 was 64.1%. The vacA s1a, m1 and i1 alleles were more prevalent in H. pylori isolates from ulcer patients (p = 0.03, p = 0.009, and p = 0.0003, respectively) and were associated with isolates with intact cagPAI. CONCLUSIONS: In Bulgaria the prevalence of intact cagPAI was high. cagE or/and cagY absence was the most important predictor of cagPAI status.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Helicobacter pylori/genética , Helicobacter pylori/patogenicidad , ADN Bacteriano/análisis , ADN Bacteriano/genética , Frecuencia de los Genes , Infecciones por Helicobacter/microbiología , Humanos , Úlcera Péptica/microbiología , Reacción en Cadena de la Polimerasa
10.
Gastroenterol Res Pract ; 2017: 9212143, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28659975

RESUMEN

The aim of this study was to assess the association between some dietary factors and prevalence of H. pylori infection or strain virulence in 294 adult asymptomatic blood donors. Methods. Seroprevalence was evaluated using ELISA. Logistic regression was used. Results. Anti-H. pylori IgG prevalence was 72.4%, and CagA IgG seroprevalence was 49.3%. In the multivariate analyses, the frequent (>5 days per week) honey consumption was associated with both reduced H. pylori seroprevalence OR, 0.68 with 95% confidence interval (CI), 0.473-0.967 and reduced CagA IgG seroprevalence OR, 0.65 with 95% CI, 0.486-0859. Frequent (>5 days per week) yoghurt consumption also was associated with lower H. pylori virulence of the strains (CagA IgG OR, 0.56 with 95% CI, 0.341-0.921). Smoking and consumption of the other dietary factors resulted in no significant differences in the prevalence of H. pylori IgG and CagA IgG within the subject groups. Conclusion. To the best of our knowledge, this is the first report revealing reverse associations between honey or yoghurt consumption and CagA IgG prevalence as well as between frequent honey consumption and lower prevalence of the H. pylori infection. Regular honey and yoghurt consumption can be of value as a supplement in the control of H. pylori therapy.

11.
Folia Microbiol (Praha) ; 61(4): 307-10, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26634607

RESUMEN

We report a case of an adult patient undergoing three unsuccessful Helicobacter pylori treatments, including proton pump inhibitor (PPI), bismuth subcitrate, metronidazole and tetracycline in 2012, PPI, amoxicillin and clarithromycin in 2013, and PPI, amoxicillin and rifampin in 2014. Following the first treatment, the isolate was metronidazole and ciprofloxacin/levofloxacin resistant. After the second treatment, the isolate was resistant to metronidazole, ciprofloxacin/levofloxacin and rifampin, developing secondary clarithromycin resistance by A2143G mutation and was susceptible only to tetracycline. After the third treatment, the patient still remained H. pylori positive. Patient's strain was highly virulent (cagA (+) , cagE (+) and vacA s1a/m1/i1). The evolution of the patient's disease was from gastroesophageal reflux disease in 2012 to two duodenal ulcers in 2015. Briefly, the infecting strain showed quadruple antibiotic resistance and a transient amoxicillin resistance. Triple clarithromycin-based treatment induced secondary clarithromycin resistance by A2143G mutation, while rifampin resistance caused the third treatment failure. Several options for the next treatment regimens are discussed.


Asunto(s)
Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Terapia Combinada/métodos , Quimioterapia/métodos , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia del Tratamiento , Factores de Virulencia/genética
12.
Microb Drug Resist ; 22(3): 227-32, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26618567

RESUMEN

Antibiotic resistance is the major cause for Helicobacter pylori eradication failure. H. pylori clarithromycin resistance mutations were evaluated in 84 (82 phenotypically clarithromycin resistant and 2 intermediately susceptible) strains by allele-specific PCR and 3'-mismatched PCR. Many (57.1%) of these strains were metronidazole resistant. Prevalence of cagA(+), cagE(+), vacA s1a, m1, i1, and i2 strains was 76.2%, 58.0%, 82.1%, 35.7%, 50.0%, and 50.0%, respectively. A2143G, A2142G, A2142C, and A2143G+A2142G mutation rates were 64.3%, 23.8%, 1.2%, and 10.7%, respectively. Strains harboring the A2142G mutation showed 5.3-fold higher clarithromycin MIC50 than those harboring the A2143G mutation. The A2143G mutation alone was 1.7-fold more common in vacA i2 strains compared with vacA i1 strains, while the A2142G mutation alone was 3-fold more frequent in vacA i1 strains than vacA i2 strains and 3.1-fold more common in metronidazole-susceptible compared with metronidazole-resistant strains. Briefly, clarithromycin resistance mutations were significantly linked to vacA i allele and metronidazole susceptibility. This is the first report about associations between the A2143G mutation and less virulent vacA i2 strains, and between the A2142G mutation and more virulent vacA i1 strains. As the 2143G mutation often predicts eradication failure by clarithromycin-based regimens, the results may be linked to the better eradication of more virulent strains compared with the less virulent strains.


Asunto(s)
Claritromicina/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/genética , Mutación/genética , Factores de Virulencia/genética , Adulto , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Niño , ADN Bacteriano/genética , Femenino , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Humanos , Masculino , Metronidazol , Pruebas de Sensibilidad Microbiana/métodos
13.
Diagn Microbiol Infect Dis ; 77(4): 287-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24075629

RESUMEN

The aim of the study was to describe oral Helicobacter pylori strain from a child by 4 methods. The strain was positive by immunofluorescence, ureA- and cagA positive, vacA s1 m2 genotype and resistant to metronidazole and clarithromycin. In conclusion, virulent and antibiotic resistant H. pylori strains can be present in oral cavity from patients with chronic dental and gastroduodenal diseases.


Asunto(s)
Técnicas de Tipificación Bacteriana , Infecciones por Helicobacter/microbiología , Helicobacter pylori/clasificación , Boca/microbiología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Claritromicina/farmacología , Genotipo , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/genética , Humanos , Metronidazol/farmacología , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa , Factores de Virulencia/genética , Factores de Virulencia/inmunología
14.
Diagn Microbiol Infect Dis ; 74(3): 253-7, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22951332

RESUMEN

The significance of the intermediate (i) region of the Helicobacter pylori vacA gene as a virulence factor associated with the severity of gastric disease is still disputable. The aim of the present study was to evaluate the prevalence and significance of vacA i alleles alone or in combination with other vacA alleles in symptomatic Bulgarian patients and to find out possible associations between vacA i genotype and patients' disease, age, sex, and other H. pylori virulence factors. Unlike vacA s1 and m1, vacA i1 prevalence was significantly higher (75.0%) in strains from peptic ulcer patients than in strains from nonulcer patients with gastric diseases (58.6%) (P = 0.022). Less virulent vacA s1 i2 m2 strains were more prevalent in females (P = 0.03), and cagA(+) was associated with vacA i1, s1, m1, and their combinations. In conclusion, vacA i status is a better predictor for the strain virulence than other vacA alleles.


Asunto(s)
Proteínas Bacterianas/genética , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/genética , Helicobacter pylori/patogenicidad , Factores de Virulencia/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bulgaria/epidemiología , Niño , Femenino , Genotipo , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/clasificación , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica/epidemiología , Úlcera Péptica/microbiología , Úlcera Péptica/patología , Prevalencia , Virulencia , Adulto Joven
15.
Diagn Microbiol Infect Dis ; 71(4): 335-40, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21937185

RESUMEN

Prevalence of outer inflammatory protein (oipA) gene functional status in Helicobacter pylori strains from Southeastern Europe is still unclear. H. pylori strains from 70 symptomatic patients were polymerase chain reaction (PCR) assessed for cagA and vacA types, and oipA gene functional status was evaluated by PCR and sequencing. Our results demonstrated a high prevalence of strains with oipA status "on" genes (81%) and strong association between them and peptic ulcers, cagA, and vacA s1 and s1/m1 genotypes, regardless of the patient gender, place of residence, and age. Importantly, most vacA i1 strains (93%) harbored oipA status "on" versus only 57% of those with vacA i2 type. The vacA i1 genotype was less frequent (66%) than both cagA and vacA s1 types. The virulent strains with cagA(+) and vacA s1, m1, and i1 were detected in 35% as a predominant genotype and almost all (96%) of these strains harbored oipA status "on". In conclusion, the high prevalence of in-frame oipA gene strains (81%), associated with peptic ulcers and cagA(+), vacA s1, m1, m2, and, importantly, i1 genotypes, indicates a strong synergistic activity of H. pylori virulence factors.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Variación Genética , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Bulgaria , Niño , ADN Bacteriano/química , ADN Bacteriano/genética , Femenino , Genotipo , Helicobacter pylori/clasificación , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica/microbiología , Úlcera Péptica/patología , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Factores de Virulencia , Adulto Joven
16.
Antonie Van Leeuwenhoek ; 100(4): 529-35, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21701821

RESUMEN

Associations of Helicobacter pylori cagE status with complex patient characteristics remain to be elucidated in Eastern Europe. The aim of this study was to assess the frequencies of cagE gene and cagA/cagE combinations in H. pylori strains from symptomatic Bulgarian patients and to improve cagA detection. cagA and cagE genotypes were evaluated in 219 patients with single-strain infections. In total, 84.9% of strains were cagA (+), while 68.5% were cagE (+). cagA (+), cagE (+), and cagA (+)/cagE (+) strains were more prevalent in peptic ulcer (93.8%, 84.4%, and 84.4%) compared with nonulcer patients (81.3%, 61.9%, and 61.3%, respectively). In elderly patients, cagE (+) and cagA (+)/cagE (+) strains were 1.9-fold more common than in the 12 children evaluated. Only 10% of the elderly subjects harbored low-virulence cagA (+)/cagE (-) strains compared with 16.8% of adults and 41.7% of children. Intriguingly, prevalence of the cagA (+)/cagE (-) genotype was 2.1-fold lower in men than in women, suggesting a higher frequency of more virulent strains in men. The presence of both cag genes and combinations was not linked to strain susceptibility to clarithromycin or metronidazole, place of residence, or prior therapy. Use of an extra primer pair increased cagA detection in 14.7% of 31 cagA (-) strains. In conclusion, use of a second primer pair for the cagA gene can be recommended in countries with common cagA (+) strains. Although both cag genes were linked to severe diseases in Bulgarian patients, the best discrimination of virulent strains was obtained by the cagA/cagE combination or by the cagE gene alone. cagE prevalence increased gradually with patient age, while the cagA (+)/cagE (-) genotype, implying a disrupted cag pathogenicity island, was associated with both younger age and female gender.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana/métodos , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bulgaria/epidemiología , Niño , Femenino , Genotipo , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/clasificación , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Antonie Van Leeuwenhoek ; 98(3): 343-50, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20454856

RESUMEN

Data on the geographic prevalence of Helicobacter pylori iceA and babA alleles in Eastern Europe are still relatively scant. The aim of this study was to evaluate the prevalence of iceA and babA genotypes in Bulgarian symptomatic patients. The iceA and babA genotypes were evaluated by PCR with pure cultures in strains from 196 and 181 patients, respectively. Mixed infections were found in 10.2% of all 196 patients. Prevalence of H. pylori genotypes in patients with single-strain infections was 69.3% for iceA1, 30.7% for iceA2, 82.4% for cagA(+), 89.2% for vacA s1, 10.8% for vacA s2, 39.8% for vacA m1, 60.2% for vacA m2 and 48.8% for babA2. Within the iceA1 positive strains, 94.3% and 88.5% were also vacA s1a and cagA positive, respectively. Of the babA2 positive strains, 100.0%, 92.4% and 72.2% were also vacA s1a, cagA and iceA1 positive, respectively. Ulcer patients had more often strains with cagA positive status and vacA s1a allele. Although neither iceA1 nor babA2 were more common in ulcer patients, the combination of both alleles was more frequent (48.1%) in the ulcer patients than in the rest (28.7%). Clarithromycin susceptible strains had more often iceA1 allele (74.4%) than the resistant strains (55.3%). In conclusion, the results demonstrated a high prevalence of virulent H. pylori in Bulgaria. Both iceA1 and babA2 genotypes were associated with other virulence factors of H. pylori and, in addition, the iceA1 allele was associated with the strain susceptibility.


Asunto(s)
Adhesinas Bacterianas/genética , Proteínas de la Membrana Bacteriana Externa/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Úlcera Gástrica/microbiología , Adhesinas Bacterianas/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Bulgaria , Niño , Farmacorresistencia Bacteriana Múltiple , Europa Oriental , Femenino , Genotipo , Helicobacter pylori/patogenicidad , Humanos , Masculino , Persona de Mediana Edad , Mutagénesis Insercional , Reacción en Cadena de la Polimerasa , Úlcera/microbiología , Virulencia , Factores de Virulencia/genética , Adulto Joven
18.
Diagn Microbiol Infect Dis ; 64(4): 374-80, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19631090

RESUMEN

The aim of the study was to evaluate the prevalence of main virulence genes in Helicobacter pylori strains from 116 patients with peptic ulcers (41 cases) and nonulcer diseases (75) by polymerase chain reaction (PCR) with pure cultures and to compare the results with those by multiplex PCR in 39 H. pylori-positive gastric biopsies in another center in Sofia, Bulgaria. Strain susceptibility to amoxicillin, metronidazole, and clarithromycin was determined by agar dilution method. By PCR with pure cultures, coinfections with multiple H. pylori strains were found in 8 (6.9%) patients who were excluded from the statistical analysis. Prevalence of toxigenic type vacA s1 was higher (91.7%) than that usually reported in Europe. cagA-positive genotype was detected in most (81.5%) strains, and almost all of them harbored vacA s1 genotype. Strains with cagA+/vacA s1a genotype were more common (80.6%) than the other genotypes (19.4%, P = 0.0001). The ulcer patients had more often virulent strains than the other patients (92.3% versus 75.4% for cagA+, 100.0% versus 87.0% for vacA s1, 100% versus 84.0% for vacA s1a, and 92.3% versus 73.9% for cagA+/vacA s1a, respectively). The prevalence of H. pylori virulence-associated genes was not associated with patients' sex and age or with the antibacterial resistance of strains. The most common H. pylori genotype was cagA+/vacA s1a. Similar prevalence of cagA-positive (82.1%), vacA s1 (97.4%), and cagA+/vacA s1 strains (79.5%) was found by multiplex PCR in gastric biopsies in the 2nd center. In conclusion, H. pylori strains with virulent genotypes are widespread in symptomatic Bulgarian patients.


Asunto(s)
Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Helicobacter pylori/patogenicidad , Antibacterianos/farmacología , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Bulgaria/epidemiología , Genotipo , Helicobacter pylori/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Reacción en Cadena de la Polimerasa/métodos , Prevalencia , Factores de Virulencia/genética
19.
J Med Microbiol ; 58(Pt 9): 1133-1148, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19528173

RESUMEN

Pseudomonas aeruginosa is one of the leading nosocomial pathogens worldwide. Nosocomial infections caused by this organism are often hard to treat because of both the intrinsic resistance of the species (it has constitutive expression of AmpC beta-lactamase and efflux pumps, combined with a low permeability of the outer membrane), and its remarkable ability to acquire further resistance mechanisms to multiple groups of antimicrobial agents, including beta-lactams, aminoglycosides and fluoroquinolones. P. aeruginosa represents a phenomenon of bacterial resistance, since practically all known mechanisms of antimicrobial resistance can be seen in it: derepression of chromosomal AmpC cephalosporinase; production of plasmid or integron-mediated beta-lactamases from different molecular classes (carbenicillinases and extended-spectrum beta-lactamases belonging to class A, class D oxacillinases and class B carbapenem-hydrolysing enzymes); diminished outer membrane permeability (loss of OprD proteins); overexpression of active efflux systems with wide substrate profiles; synthesis of aminoglycoside-modifying enzymes (phosphoryltransferases, acetyltransferases and adenylyltransferases); and structural alterations of topoisomerases II and IV determining quinolone resistance. Worryingly, these mechanisms are often present simultaneously, thereby conferring multiresistant phenotypes. This review describes the known resistance mechanisms in P. aeruginosa to the most frequently administrated antipseudomonal antibiotics: beta-lactams, aminoglycosides and fluoroquinolones.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana/fisiología , Pseudomonas aeruginosa/efectos de los fármacos
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