A carregar...
Publicação
Perfil de resistência aos antibióticos e caracterização molecular de estirpes resistentes de Neisseria gonorrhoeae isoladas numa população de homens que têm sexo com homens da área de Lisboa
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 1.7 MB | Adobe PDF |
Autores
Orientador(es)
Resumo(s)
A infeção por Neisseria gonorrhoeae é a segunda infeção sexualmente transmissível mais prevalente na Europa. Atualmente, a terapêutica indicada para o tratamento da infeção por N. gonorrhoeae consiste na administração de ceftriaxona em combinação com a azitromicina. No entanto, foram relatadas falhas terapêuticas após a administração de cefalosporinas de terceira geração, a nível mundial.
A inexistência de uma alternativa à terapêutica de primeira linha, adequada e eficaz, torna imperativo a realização de vigilância epidemiológica de resistências, sobretudo nas populações de risco, como os homens que têm sexo com homens (HSH).
O conhecimento abrangente sobre a base genética associada a perfis de suscetibilidade e resistência aos antibióticos tem elevada importância, uma vez que os testes de amplificação de ácidos nucleicos estão a substituir rapidamente o método de cultura no diagnóstico de infeção por N. gonorrhoeae.
O teste de suscetibilidade aos antibióticos foi realizado para a penicilina, a tetraciclina, a espectinomicina, a ceftriaxona, a cefixima, a ciprofloxacina e a azitromicina, através dos métodos difusão em disco e Etest, de forma a obter-se o fenótipo de resistência de cada isolado de N. gonorrhoeae em estudo. Com base no fenótipo de resistência, pesquisou-se a presença de mutações nos genes penA, mtrR, parC e gyrA.
Assim, na população estudada (homens que têm sexo com homens) obtiveram-se 30 culturas positivas para N. gonorrhoeae, das quais 73% apresentaram resistência intermédia ou resistência à penicilina, 60% à tetraciclina e 37% à ciprofloxacina.
O reduzido número de casos positivos não permitiu retirar conclusões com valor estatístico quantitativo, no entanto, qualitativamente, permitiu compreender que as mutações detetadas são idênticas às obtidas por outros autores, estando associadas a fenótipos de resistência.
Neisseria gonorrhoeae infection is the second most prevalent sexually transmitted infection in Europe. Currently, dual therapy for N. gonorrhoeae infections (e.g., treatments including ceftriaxone and azithromycin) is now recommended. However, treatment failures have been reported following administration of third-generation cephalosporins. The lack of an appropriate and effective alternative for first-line therapy makes it imperative to carry out epidemiological surveillance of resistance, especially among at-risk populations, such as men who have sex with men (MSM). In an era in which N. gonorrhoeae infection is increasingly being diagnosed by nucleic acid amplification tests, knowledge on molecular surveillance of resistance, is highly important. Antibiotic susceptibility testing was carried out to penicillin, tetracycline, spectinomycin, ceftriaxone, the cefixime, ciprofloxacin, and azithromycin, by the diffusion disc and Etest methods, so as to obtain the resistance phenotype of each N. gonorrhoeae isolate under study. Polymerase chain reaction and direct DNA sequencing were performed to identify mutations within the penA, mtrR, gyrA and parC genes of the isolates, which thus explain the resistant phenotypes. Thus, the study population (men who have sex with men) yielded 30 positive cultures for N. gonorrhoeae, of which 73% had intermediate resistance or resistance to penicillin, 60% to tetracycline and 37% to ciprofloxacin. The reduced number of positive cases does not allow us to draw conclusions in quantitative statistical value. However, allowed in qualitative conclusions that the detected mutations are identical to those obtained by other authors, and are associated with resistance phenotypes.
Neisseria gonorrhoeae infection is the second most prevalent sexually transmitted infection in Europe. Currently, dual therapy for N. gonorrhoeae infections (e.g., treatments including ceftriaxone and azithromycin) is now recommended. However, treatment failures have been reported following administration of third-generation cephalosporins. The lack of an appropriate and effective alternative for first-line therapy makes it imperative to carry out epidemiological surveillance of resistance, especially among at-risk populations, such as men who have sex with men (MSM). In an era in which N. gonorrhoeae infection is increasingly being diagnosed by nucleic acid amplification tests, knowledge on molecular surveillance of resistance, is highly important. Antibiotic susceptibility testing was carried out to penicillin, tetracycline, spectinomycin, ceftriaxone, the cefixime, ciprofloxacin, and azithromycin, by the diffusion disc and Etest methods, so as to obtain the resistance phenotype of each N. gonorrhoeae isolate under study. Polymerase chain reaction and direct DNA sequencing were performed to identify mutations within the penA, mtrR, gyrA and parC genes of the isolates, which thus explain the resistant phenotypes. Thus, the study population (men who have sex with men) yielded 30 positive cultures for N. gonorrhoeae, of which 73% had intermediate resistance or resistance to penicillin, 60% to tetracycline and 37% to ciprofloxacin. The reduced number of positive cases does not allow us to draw conclusions in quantitative statistical value. However, allowed in qualitative conclusions that the detected mutations are identical to those obtained by other authors, and are associated with resistance phenotypes.
Descrição
Palavras-chave
Neisseria gonorrhoeae Microbiologia médica Epidemiologia Doenças sexualmente transmissíveis Gonorreia Terapêutica
Contexto Educativo
Citação
Editora
Instituto de Higiene e Medicina Tropical