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1.
Indian J Microbiol ; 64(2): 389-401, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39011017

RESUMO

Klebsiella pneumoniae, a member of the autochthonous human gut microbiota, utilizes a variety of virulence factors for survival and pathogenesis. Consequently, it is responsible for several human infections, including urinary tract infections, respiratory tract infections, liver abscess, meningitis, bloodstream infections, and medical device-associated infections. The main studied virulence factors in K. pneumoniae are capsule-associated, fimbriae, siderophores, Klebsiella ferric iron uptake, and the ability to metabolize allantoin. They are crucial for virulence and were associated with specific infections in the mice infection model. Notably, these factors are also prevalent in strains from the same infections in humans. However, the type and quantity of virulence factors may vary between strains, which defines the degree of pathogenicity. In this review, we summarize the main virulence factors investigated in K. pneumoniae from different human infections. We also cover the specific identification genes and their prevalence in K. pneumoniae, especially in hypervirulent strains.

2.
BMC Infect Dis ; 19(1): 609, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296179

RESUMO

BACKGROUND: Bloodstream infections (BSI) are associated with high morbidity and mortality. This scenario worsens with the emergence of drug-resistant pathogens, resulting in infections which are difficult to treat or even untreatable with conventional antimicrobials. The aim of this study is to describe the epidemiological aspects of BSI caused by multiresistant gram-negative bacilli (MDR-GNB). METHODS: We conducted a laboratory-based surveillance for gram-negative bacteremia over a 1-year period. The bacterial isolates were identified by MALDI-TOF/MS and the antimicrobial susceptibility testing was performed by VITEK®2. Resistance genes were identified through PCR assays. RESULTS: Of the 143 patients, 28.7% had infections caused by MDR-GNB. The risk factors for MDR bacteremia were male sex, age ≥ 60, previous antimicrobial use, liver disease and bacteremia caused by K. pneumoniae. K. pneumoniae was the most frequently observed causative agent and had the highest resistance level. Regarding the resistance determinants, SHV, TEM, OXA-1-like and CTX-M-gp1 were predominant enzymatic variants, whereas CTX-M-gp9, CTX-M-gp2, KPC, VIM, GES, OXA-48-like, NDM and OXA-23-like were considered emerging enzymes. CONCLUSIONS: Here we demonstrate that clinically relevant antibiotic resistance genes are prevalent in this setting. We hope our findings support the development of intervention measures by policy makers and healthcare professionals to face antibiotic resistance.


Assuntos
Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Adolescente , Adulto , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Brasil/epidemiologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Infecções por Klebsiella/microbiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência
3.
BMC Infect Dis ; 15: 302, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26223380

RESUMO

BACKGROUND: Hospital-based surveillance for pneumococcal meningitis has been conducted since January 1996 in the city of Salvador, Brazil. The purpose of this study was to describe the temporal evolution of Penicillin Non-Susceptible Streptococcus pneumoniae (PNSSP) in regards to serotype distributions and clonal diversity recovered from meningitis cases over 17 years. METHODS: Broth microdilution was used to identify pneumococcal isolates that were PNSSP (Minimum Inhibitory Concentration > 0.12 µg/ml). The annual incidence rate of meningitis cases was calculated. Serotyping was defined using multiplex polymerase chain reaction assays and quellung reaction. Genetic diversity of PNSSP isolates was assessed using both pulsed-field gel electrophoresis (PFGE) and Multilocus Sequence Typing (MLST) analyses. RESULTS: A total of 854 cerebrospinal fluid (CSF) culture pneumococcal isolates were tested by broth microdilution method and serotyped. A total of 173 (20.3%) were penicillin non-susceptible (PNSSP) (Minimum Inhibitory concentration ≥ 0.12 µg/ml). The annual incidence of meningitis cases declined from 1.65/100,000 population (1996) to 0.2/100,000 population in 2012 and the rate due to PNSSP declined 82% over the 17-years of surveillance. PNSSP isolates were restricted to 13 serotypes, being the most common ones serotypes 14 (45.1%; 78/173), 23 F (19.1%; 33/173), 6B (14.4%; 25/173), 19 F (9.2%; 16/173) and 19A (5.2%; 9/173). Among the PNSSP isolates, 94% had serotypes represented in the 10-valent conjugate vaccine (PCV10). The predominant serotype 14 clonal groups were identified as PFGE group A/multilocus sequence type 66 (ST66) [35.3% (61/173)] and PFGE group GK/ST156 [4.6% (8/173)], the latter one associated with high level resistance to penicillin and ceftriaxone. CONCLUSIONS: Our results show sustained reductions in pneumococcal meningitis cases in the Metropolitan region of Salvador from 1996 to 2012. This might reflect a beneficial impact of conjugate vaccines. Continued surveillance and further studies need to be conducted to better understanding on PCV10 vaccine impact.


Assuntos
Meningite Pneumocócica/epidemiologia , Meningite Pneumocócica/microbiologia , Resistência às Penicilinas , Streptococcus pneumoniae/classificação , Variação Antigênica , Técnicas de Tipagem Bacteriana/métodos , Brasil/epidemiologia , Ceftriaxona/uso terapêutico , Criança , Pré-Escolar , Feminino , Variação Genética , Humanos , Incidência , Lactente , Masculino , Meningite Pneumocócica/tratamento farmacológico , Meningite Pneumocócica/prevenção & controle , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase Multiplex , Penicilina G/uso terapêutico , Resistência às Penicilinas/genética , Resistência às Penicilinas/imunologia , Vacinas Pneumocócicas/uso terapêutico , Sorotipagem , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/imunologia , Fatores de Tempo , Vacinas Conjugadas/uso terapêutico
4.
Braz J Infect Dis ; 28(1): 103705, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38065221

RESUMO

BACKGROUND: The COVID-19 pandemic has triggered crises in the public health sector that have complex and multifaceted interrelationships with antimicrobial resistance. It is important to evaluate the impact of COVID-19 on microbiological profile, antibiotic and alcohol gel consumption in Intensive Care Units (ICU). METHODS: This is a retrospective study undertaken in an infectious disease hospital located in Bahia/Brazil during three periods: from March 2019 to February 2020; from March 2020 to February 2021; and from March 2021 to February 2022. It was evaluated the incidence density of Candida spp and of multidrug-resistant Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species (ESKAPE group) in blood, urine and tracheal secretion isolated 48 h after the patient's admission to the ICU, as well as the use of alcohol gel (in milliliters) and consumption of antibiotics in Defined Daily Dose (DDD) per 1,000 ICU patient-days in the previous year and in the first two years of COVID-19 pandemic. RESULTS: There was an increase in Candida spp. (5.81, p < 0.001, IRR = 10.47, 95 % CI 2.57‒42.62) and in carbapenem-resistant A. baumannii in clinical cultures (4.71, p < 0.001, IRR = 8.46, 95 % CI 2.07‒34.60), the latter mainly in tracheal secretions (3.18, p= 0.02, IRR = 11.47, 95 % CI 1.58‒83.39). A rise in the consumption of ceftriaxone and piperacillin-tazobactam, along with an increase in the utilization of alcohol gel were observed. CONCLUSION: The shifting microbiological profile can be attributed to both the unique characteristics of patients with COVID-19 and the adjustments made to healthcare facilities' structural and work routines. Understanding these changes is essential in addressing the accelerated impact of antimicrobial resistance during the pandemic. Therefore, conducting thorough reviews of institutional practices and routines becomes critical in mitigating the consequences of antimicrobial resistance and its implications for patient care.


Assuntos
COVID-19 , Doenças Transmissíveis , Infecção Hospitalar , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Brasil/epidemiologia , Infecção Hospitalar/microbiologia , Pandemias , Doenças Transmissíveis/tratamento farmacológico , Hospitais , Unidades de Terapia Intensiva
5.
Rev Soc Bras Med Trop ; 57: e00805, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597526

RESUMO

Streptococcus suis has been widely reported as a pathogen in animals, especially pigs. In terms of human health implications, it has been characterized as a zoonosis associated with the consumption of pork products and occupational exposure, particularly in Southeast Asian countries. Here, we present a rare case of human S. suis infection in Brazil, diagnosed in an older adult swine farmer, a small rural producer residing in the semi-arid region of Bahia, Brazil.


Assuntos
Meningites Bacterianas , Infecções Estreptocócicas , Streptococcus suis , Animais , Humanos , Suínos , Brasil/epidemiologia , Zoonoses , Infecções Estreptocócicas/diagnóstico , Meningites Bacterianas/diagnóstico
6.
PLoS One ; 19(6): e0298579, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38905178

RESUMO

BACKGROUND: As new and improved antigen-detecting rapid diagnostic tests for SARS-CoV-2 infection (Ag-RDT) continue to be developed, assessing their diagnostic performance is necessary to increase test options with accurate and rapid diagnostic capacity especially in resource-constrained settings. This study aimed to assess the performance of two Ag-RDTs in a population-based study. METHODS: We conducted a diagnostic accuracy study in neighborhoods with high socioeconomic vulnerability in Salvador-Brazil, including individuals aged ≥12 years old who attended primary health services, between July and December 2022, with COVID-19 symptoms or who had been in contact with a confirmed case. Two Ag-RDTs were compared in parallel using reverse transcription polymerase chain reaction (RT-PCR) as reference standard, the PanbioTM COVID-19 Ag test (Abbott®) and Immuno-Rapid COVID-19 Ag (WAMA Diagnostic®). Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. RESULTS: For the Abbott test the sensitivity was 52.7% (95% CI: 44.3% - 61.0%), specificity 100% (95% CI: 98.7% - 100%), PPV 100% (95% CI: 95.4% - 100%) and NPV 80.4% (95% CI: 75.9% - 84.4%). For the WAMA test, the sensitivity was 53.4% (95% CI: 45.0% - 61.6%), specificity 100% (95% CI: 98.7% - 100%), PPV 100% (95% CI: 95.4% - 100%) and NPV 80.7% (95% CI: 76.2% - 84.6%). Sensitivity for the group with Cycle Threshold (CT) <24 was 82.3% (95%CI: 72.1-90.0, n = 83) for PanbioTM COVID-19 Ag test and 87.3% (95%CI: 77.9-93.8, n = 83) for Immuno-Rapid COVID-19 Ag test. CONCLUSION: Sensitivity for both Ag-RDT was lower than reported by manufacturers. In the stratified analysis, sensitivity was higher among those with lower CT values <24. Specificity was high for both rapid antigen tests. Both Ag-RDT showed to be useful for rapid diagnostic of potential cases of COVID-19. Negative results must be assessed carefully according to clinical and epidemiological information.


Assuntos
Teste Sorológico para COVID-19 , COVID-19 , SARS-CoV-2 , Sensibilidade e Especificidade , Humanos , COVID-19/diagnóstico , COVID-19/imunologia , COVID-19/epidemiologia , Masculino , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Adulto , Feminino , Pessoa de Meia-Idade , Brasil/epidemiologia , Criança , Teste Sorológico para COVID-19/métodos , Adolescente , Antígenos Virais/imunologia , Adulto Jovem , Idoso , Fatores Socioeconômicos
7.
Vaccine ; 42(3): 591-597, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38184393

RESUMO

BACKGROUND: In 2010, Brazil introduced the ten-valent pneumococcal conjugate vaccine (PCV10) in the national infant immunization program. Limited data on the long-term impact of PCV10 are available from lower-middle-income settings. We examined invasive pneumococcal disease (IPD) in Salvador, Bahia, over 11 years. METHODS: Prospective laboratory-based surveillance for IPD was carried out in 9 hospitals in the metropolitan region of Salvador from 2008 to 2018. IPD was defined as Streptococcus pneumoniae cultured from a normally sterile site. Serotype was determined by multiplex polymerase chain reaction and/or Quellung reaction. Incidence rates per 100,000 inhabitants were calculated for overall, vaccine-type, and non-vaccine-type IPD using census data as the denominator. Incidence rate ratios (IRRs) were calculated to compare rates during the early (2010-2012), intermediate (2013-2015), and late (2016-2018) post-PCV10 periods in comparison to the pre-PCV10 period (2008-2009). RESULTS: Pre-PCV10, overall IPD incidence among all ages was 2.48/100,000. After PCV10 introduction, incidence initially increased (early post-PCV10 IRR 3.80, 95% CI 1.18-1.99) and then declined to 0.38/100,000 late post-PCV10 (IRR 0.15; 95% CI 0.09-0.26). The greatest reductions in the late post-PCV10 period were observed in children aged ≤2 years, with no cases (IRR not calculated) and those ≥60 years (IRR 0.11, 95% CI 0.03-0.48). Late post-PCV10, significant reductions were observed for both PCV10 serotypes (IRR 0.02; 95% CI 0.0-0.15) and non-PCV10 serotypes (IRR 0.27; 95%CI 0.14-0.53). Non-PCV10 serotypes 15B, 12F, 3, 17F, and 19A became predominant late post-PCV10 without a significant increase in serotype-specific IPD incidence compared to pre-PCV10. CONCLUSION: Significant declines in IPD, including among adults not eligible for vaccination, suggest direct and indirect protection up to nine years after PCV10 introduction, without evidence of significant replacement disease. Continued surveillance is needed to monitor changes in non-vaccine serotypes and inform decisions about introducing higher valent PCVs.


Assuntos
Infecções Pneumocócicas , Lactente , Criança , Adulto , Humanos , Brasil/epidemiologia , Estudos Prospectivos , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Sorogrupo , Incidência , Vacinas Conjugadas
8.
BMJ Open ; 12(4): e059824, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428648

RESUMO

OBJECTIVES: To determine the incidence, aetiology and pneumococcal serotype distribution of community-acquired pneumonia (CAP) in Brazilian adults during a 2-year period. DESIGN: Prospective population-based surveillance study. SETTING: Patients from two emergency hospitals in Brazil were consecutively included in this study. PARTICIPANTS: A total of 111 adults aged 50 years and older with radiographically-confirmed CAP requiring an emergency department visit were prospectively enrolled between January 2018 and January 2020. MAIN OUTCOME MEASURES: Incidence rates of CAP were calculated according to age and pathogen. Pathogens were identified by conventional microbiological methods. Additionally, a novel, Luminex-based serotype specific urinary antigen detection assay was used to detect serotypes included in pneumococcal vaccines. RESULTS: Mean age of participants was 64 years and 31% were aged ≥70 years. Aetiology was established in 61 (57%) patients; among identified cases, the most common pathogens were Streptococcus pneumoniae (42/61, 69%) and influenza (4/61, 7%). Among serotypes identified from the 42 cases of pneumococcal CAP, estimated coverage ranged by pneumococcal vaccine formulations from 47.6% (13-valent), 59.5% (20-valent, licenced in the USA only) and 71.4% (23-valent). In patients with CAP, 20-valent pneumococcal vaccine serotypes were identified 2.5 times more frequently than 10-valent pneumococcal vaccine serotypes (22.5% vs 9.0%). The incidence rate for CAP in adults aged ≥50 years was 20.1 per 10 000 person-years. In general, the incidence of CAP increased consistently with age, reaching 54.4 (95% CI 36.8 to -76.6) per 10 000 in adults 80 years or older. CONCLUSIONS: We observed a high burden of pneumococcal CAP among adults in Brazil. Despite the routine immunisation of children and high-risk adults against pneumococcal disease in the Brazilian national vaccination programme, a persistent burden of pneumococcal CAP caused by vaccine serotypes remains in this population.


Assuntos
Infecções Comunitárias Adquiridas , Infecções Pneumocócicas , Pneumonia Pneumocócica , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/prevenção & controle , Humanos , Incidência , Pessoa de Meia-Idade , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Pneumonia Pneumocócica/epidemiologia , Pneumonia Pneumocócica/prevenção & controle , Estudos Prospectivos , Sorogrupo , Streptococcus pneumoniae , Vacinas Conjugadas , Conduta Expectante
9.
J Biomol Struct Dyn ; 40(24): 14223-14235, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34766882

RESUMO

The past two decades have been marked by a global spread of bacterial resistance to ß-lactam drugs and carbapenems derivatives are the ultimate treatment against multidrug-resistant bacteria. ß-lactamase expression is related to resistance which demands the development of bacterial resistance blockers. Drug inhibitor combinations of serine-ß-lactamase and ß-lactam were successful employed in therapy despite their inactivity against New Delhi metallo-beta-lactamase (NDM). Until now, few compounds are active against NDM-producing bacteria and no specific inhibitors are available yet. The rational strategy for NDM inhibitors development starts with in vitro assays aiming to seek compounds that could act synergistically with ß-lactam antibiotics. Thus, eight thiosemicarbazone derivatives were synthesized and investigated for their ability to reverse the resistant phenotype in NDM in Enterobacter cloacae. Phenotypic screening indicated that four isatin-beta-thiosemicarbazones showed Fractional Inhibitory Concentration (FIC) ≤ 250 µM in the presence of meropenem (4 µg/mL). The most promising compound (FIC= 31.25 µM) also presented synergistic effect (FICI = 0.34). Docking and molecular dynamics studies on NDM-thiosemicarbazone complex suggested that 2,3-dihydro-1H-indol-2-one subunit interacts with catalytic zinc and interacted through hydrogen bonds with Asp124 acting like a carboxylic acid bioisostere. Additionally, thiosemicarbazone tautomer with oxidized sulfur (thione) seems to act as a spacer rather than zinc chelator, and the aromatic moieties are stabilized by pi-pi and cation-pi interactions with His189 and Lys221 residues. Our results addressed some thiosemicarbazone structural changes to increase its biological activity against NDM and highlight its scaffold as promising alternatives to treat bacterial resistance.Communicated by Ramaswamy H. Sarma.


Assuntos
Antibacterianos , Tiossemicarbazonas , Antibacterianos/farmacologia , Antibacterianos/química , Tiossemicarbazonas/farmacologia , beta-Lactamases/metabolismo , beta-Lactamas/farmacologia , Fenótipo , Inibidores de beta-Lactamases/farmacologia , Inibidores de beta-Lactamases/química , Testes de Sensibilidade Microbiana
10.
Front Microbiol ; 13: 831770, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356529

RESUMO

Multidrug-resistant gram-negative bacteria, such as carbapenem and colistin-resistant Klebsiella pneumoniae (ColR-CRKP), represent a major problem for health systems worldwide and have high lethality. This study investigated the genetic relationship, antimicrobial susceptibility profile, and resistance mechanisms to ColR-CRKP isolates from patients infected/colonized in a tertiary hospital in Salvador, Bahia/Brazil. From September 2016 to January 2018, 46 patients (56 ColR-CRKP positive cultures) were enrolled in the investigation but clinical and demographic data were obtained from 31 patients. Most of them were men (67.7%) and elderly (median age of 62 years old), and the median Charlson score was 3. The main comorbidities were systemic arterial hypertension (38.7%), diabetes (32.2%), and cerebrovascular disease (25.8%). The average hospitalization stay until ColR-CRKP identification in days were 35.12. A total of 90.6% used mechanical ventilation and 93.7% used a central venous catheter. Of the 31 patients who had the data evaluated, 12 had ColR-CRKP infection, and seven died (58.4%). Previous use of polymyxins was identified in 32.2% of the cases, and carbapenems were identified in 70.9%. The minimum inhibitory concentration (MIC) for colistin was > 16 µg/mL, with more than half of the isolates (55%) having a MIC of 256 µg/mL. The bla KPC gene was detected in 94.7% of the isolates, bla NDM in 16.0%, and bla GES in 1.7%. The bla OXA-48, bla VIM, and bla IMP genes were not detected. The mcr-1 test was negative in all 56 isolates. Alteration of the mgrB gene was detected in 87.5% (n = 49/56) of the isolates, and of these, 49.0% (24/49) had alteration in size probably due to IS903B, 22.4% (11/49) did not have the mgrB gene detected, 20.4% (10/49) presented the IS903B, 6.1% (3/49) had a premature stop codon (Q30*), and 2.1% (1/49) presented a thymine deletion at position 104 - 104delT (F35fs). The PFGE profile showed a monoclonal profile in 84.7% of the isolates in different hospital sectors, with ST11 (CC-258) being the most frequent sequence type. This study presents a prolonged outbreak of ColR-CRKP in which 83.9% of the isolates belonged to the same cluster, and 67.6% of the patients evaluated had not used polymyxin, suggesting the possibility of cross-transmission of ColR-CRKP isolates.

11.
J Clin Microbiol ; 49(1): 409-12, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21048010

RESUMO

Group G Streptococcus has been implicated as a causative agent of pharyngitis in outbreak situations, but its role in endemic disease remains elusive. We found an unexpected inverse association of Streptococcus dysgalactiae subsp. equisimilis colonization and sore throat in a study of 2,194 children of 3 to 15 years of age in Salvador, Brazil.


Assuntos
Portador Sadio/epidemiologia , Faringite/epidemiologia , Infecções Estreptocócicas/epidemiologia , Streptococcus/classificação , Streptococcus/isolamento & purificação , Adolescente , Brasil/epidemiologia , Portador Sadio/microbiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Faringite/microbiologia , Áreas de Pobreza , Prevalência , Infecções Estreptocócicas/microbiologia
12.
Mem Inst Oswaldo Cruz ; 106(8): 948-56, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22241116

RESUMO

We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.


Assuntos
Doença de Chagas/parasitologia , Trypanosoma cruzi/genética , Animais , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Consenso , DNA de Protozoário/genética , Didelphis/parasitologia , Surtos de Doenças , Reservatórios de Doenças/parasitologia , Genótipo , Humanos , Insetos Vetores/parasitologia , RNA Ribossômico/genética , Triatoma/parasitologia , Trypanosoma cruzi/classificação , Trypanosoma cruzi/patogenicidade
13.
Comp Immunol Microbiol Infect Dis ; 77: 101664, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34091280

RESUMO

Leptospirosis, a zoonotic disease with worldwide distribution, is caused by spirochetes of the genus Leptospira. In dogs, this disease is frequently misdiagnosed. Few studies have attempted to associate the detection of Leptospira spp. infection with clinicopathological and renal histopathological findings using a multidisciplinary approach. The present study isolated and characterized Leptospira spp. obtained from naturally infected dogs and described relevant clinical and histopathological findings. Blood and urine were collected from 57 dogs with clinical symptomatology suggestive of leptospirosis; 38 cases were confirmed by PCR in urine or by culture or microscopic agglutination testing (titers ≥800). A total of 12 strains of pathogenic Leptospira were isolated from the studied dogs (seven in blood, four in urine and one in both blood and urine samples). All isolates were characterized as Leptospira interrogans serogroup Icterohaemorrhagiae. Of the confirmed cases, almost one-third of the animals had been vaccinated. Our analysis of laboratory testing revealed that azotemia and proteinuria were statistically significant predictors of infection. The main histopathological findings seen in kidney tissues were necrosis, degeneration, tubular regeneration, mononuclear inflammatory infiltrate and congestion. A multidisciplinary approach involving clinicopathological and histopathological characterization of renal involvement can aid in the identification of acute leptospirosis infection.


Assuntos
Doenças do Cão , Leptospira interrogans , Leptospira , Leptospirose , Animais , Doenças do Cão/diagnóstico , Cães , Leptospira interrogans/genética , Leptospirose/diagnóstico , Leptospirose/veterinária , Estudos Prospectivos , Sorogrupo
14.
Hematol Transfus Cell Ther ; 42(2): 139-144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31806417

RESUMO

Sickle cell anemia (SCA) is a common genetic blood disorder, affecting millions worldwide. According to current evidence, individuals with SCA have more than 300 times greater risk to develop bacterial meningitis (BM) than the general population. Herein we have described the characteristics of a series of BM cases in SCA patients in Salvador, Brazil, during 13 years of hospital-based surveillance. Data on clinical presentation, laboratory parameters and outcomes were collected retrospectively by reviewing medical records. From 1999 to 2011, ten SCA patients were identified among the 2511 cases of BM (10/2511; 0.40%). These patients were more likely to be male (90%) and to be younger (median age 8.5 years). The causative agents were Streptococcus pneumoniae (n=5) and Haemophilus influenzae (n=1). The most frequent pneumococcal serotypes were 23F (2 cases), 14, 18F, 23B (one case each). Common medical complications were stroke (n=3); heart failure (n=2), respiratory problems (n=2), renal dysfunctions (n=2) and leg ulcers (n=1). This study highlights the importance of S. pneumoniae as a causative agent of meningitis in individuals with SCA and shows the diversity of comorbidities associated with this condition.

15.
PLoS One ; 15(9): e0239664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32991620

RESUMO

OBJECTIVES: This study aims to describe the oral microbiome diversity and prevalence of ARGs in periodontal health and disease. BACKGROUND: The human oral cavity harbors a complex microbial community known as the oral microbiome. These organisms are regularly exposed to selective pressures, such as the usage of antibiotics, which drive evolution and acquisition of antibiotic resistance genes (ARGs). Resistance among oral bacteria jeopardizes not only antibiotic therapy for oral infections, but also extra-oral infections caused by bacterial translocation. METHODS: We carried out a cross-sectional investigation. Saliva and subgingival plaque samples were collected during a clinical exam. 16S rRNA gene sequencing was performed to assess microbial diversity. Resistance genes were identified through PCR assays. RESULTS: Of the 110 participants, only 22.7% had healthy periodontium, while the majority was diagnosed with gingivitis (55.4%) and chronic periodontitis (21.8%). The composition of the oral microbiota differed from healthy and diseased samples, being Streptococcus spp. and Rothia spp. predominant in periodontal disease. Regarding ARGs, 80 (72.7%) samples were positive for at least one of genes screened, erm being the most frequent variant (58.2%), followed by blaTEM (16.4%), mecA (2.7%), pbp2b and aac(6 ') (1.8%). Neither genes coding resistance to carbapenems nor metronidazole were detected. CONCLUSIONS: Our findings indicate that there are no significant differences in terms of taxonomic enrichment between healthy and diseased oral microbiomes. However, samples retrieved from healthy patients had a more diverse microbial community, whereas diseased samples have lower taxonomic diversity. We have also identified clinically relevant ARGs, providing baseline information to guide antibiotic prescription in dentistry.


Assuntos
Bactérias/isolamento & purificação , Farmacorresistência Bacteriana/genética , Microbiota , Boca/microbiologia , Adolescente , Adulto , Bactérias/genética , Proteínas de Bactérias/genética , Estudos Transversais , Placa Dentária/microbiologia , Placa Dentária/patologia , Feminino , Gengivite/diagnóstico , Gengivite/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Periodontite/diagnóstico , Periodontite/microbiologia , Periodonto/patologia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/metabolismo , Saliva/microbiologia , Streptococcus/genética , Streptococcus/isolamento & purificação , Adulto Jovem
16.
Rev. Soc. Bras. Med. Trop ; 57: e00805, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1559187

RESUMO

ABSTRACT Streptococcus suis has been widely reported as a pathogen in animals, especially pigs. In terms of human health implications, it has been characterized as a zoonosis associated with the consumption of pork products and occupational exposure, particularly in Southeast Asian countries. Here, we present a rare case of human S. suis infection in Brazil, diagnosed in an older adult swine farmer, a small rural producer residing in the semi-arid region of Bahia, Brazil.

17.
Braz. j. infect. dis ; 28(1): 103705, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550143

RESUMO

Abstract Background The COVID-19 pandemic has triggered crises in the public health sector that have complex and multifaceted interrelationships with antimicrobial resistance. It is important to evaluate the impact of COVID-19 on microbiological profile, antibiotic and alcohol gel consumption in Intensive Care Units (ICU). Methods This is a retrospective study undertaken in an infectious disease hospital located in Bahia/Brazil during three periods: from March 2019 to February 2020; from March 2020 to February 2021; and from March 2021 to February 2022. It was evaluated the incidence density of Candida spp and of multidrug-resistant Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species (ESKAPE group) in blood, urine and tracheal secretion isolated 48 h after the patient's admission to the ICU, as well as the use of alcohol gel (in milliliters) and consumption of antibiotics in Defined Daily Dose (DDD) per 1,000 ICU patient-days in the previous year and in the first two years of COVID-19 pandemic. Results There was an increase in Candida spp. (5.81, p < 0.001, IRR = 10.47, 95 % CI 2.57‒42.62) and in carbapenem-resistant A. baumannii in clinical cultures (4.71, p < 0.001, IRR = 8.46, 95 % CI 2.07‒34.60), the latter mainly in tracheal secretions (3.18, p =0.02, IRR = 11.47, 95 % CI 1.58‒83.39). A rise in the consumption of ceftriaxone and piperacillin-tazobactam, along with an increase in the utilization of alcohol gel were observed. Conclusion The shifting microbiological profile can be attributed to both the unique characteristics of patients with COVID-19 and the adjustments made to healthcare facilities' structural and work routines. Understanding these changes is essential in addressing the accelerated impact of antimicrobial resistance during the pandemic. Therefore, conducting thorough reviews of institutional practices and routines becomes critical in mitigating the consequences of antimicrobial resistance and its implications for patient care.

19.
Microbes Infect ; 20(1): 19-24, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28962886

RESUMO

Invasive meningococcal disease (IMD) is a major public health problem worldwide. An epidemic of serogroup C (NmC) IMD occurred in 2010 in the city of Salvador. In this study, we describe the antigenic and genetic characterization of meningococcal isolates collected from meningitis cases in Salvador from 2001 to 2012. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were performed for the analysis of IMD isolates. A total of 733 cases were identified, and the serogroup was determined for 391 (53.0%) of these. Most cases were caused by NmC (53%) or B (47%). The most prevalent strains were B:4,7:P1.19,15 (32.9%; 129/391) and C:23:P1.14-6 (28.6%; 112/391). Based on PFGE/MLST analysis, 71.3% (77/108 PFGE-tested isolates) clustered as two clones of sequence type ST-3779 and ST-3780, both belonging to the ST-103 clonal complex. ST-3779 has been detected in Salvador since 1996 and together with ST-3780 became predominant after 2005. There was a predominance of C:23:P1.14-6, ST-3779/3780 in Salvador during the period of 2007-2012, establishing a major clonal lineage, which remained in the community for a long time; this has serious implications for public health, particularly in terms of prevention and control strategies of IMD.


Assuntos
Meningite Meningocócica/epidemiologia , Neisseria meningitidis Sorogrupo C/genética , Adolescente , Adulto , Fatores Etários , Brasil/epidemiologia , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Masculino , Meningite Meningocócica/líquido cefalorraquidiano , Meningite Meningocócica/mortalidade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Neisseria meningitidis/classificação , Neisseria meningitidis/genética , Neisseria meningitidis Sorogrupo C/classificação , Sorogrupo , Sorotipagem , Adulto Jovem
20.
Appl Biochem Biotechnol ; 182(4): 1518-1539, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28211009

RESUMO

Streptococcus pneumoniae is a colonizer of the human nasopharynx, which accounts for most of the community-acquired pneumonia cases and can cause non-invasive and invasive diseases. Current available vaccines are serotype-specific and the use of recombinant proteins associated with virulence is an alternative to compose vaccines and to overcome these problems. In a previous work, we describe the identification of proteins in S. pneumoniae by reverse vaccinology and the genetic diversity of these proteins in clinical isolates. It was possible to purify a half of 20 selected proteins in soluble form. The expression of these proteins on the pneumococcal cells surface was confirmed by flow cytometry. We demonstrated that some of these proteins were able to bind to extracellular matrix proteins and were recognized by sera from patients with pneumococcal meningitis infection caused by several pneumococcal serotypes. In this context, our results suggest that these proteins may play a role in pneumococcal pathogenesis and might be considered as potential vaccine candidates.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Reações Cruzadas , Proteínas da Matriz Extracelular/metabolismo , Genômica , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/imunologia , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/isolamento & purificação , Clonagem Molecular , Camundongos , Vacinas Pneumocócicas/imunologia , Ligação Proteica , Sorogrupo , Streptococcus pneumoniae/metabolismo
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