Post-antibiotic era in hemodialysis? Two case reports of simultaneous colonization and bacteremia by multidrug-resistant bacteria.

The emergence of resistance mechanisms not only limits the therapeutic options for common bacterial infections but also worsens the prognosis in patients who have conditions that increase the risk of bacterial infections. Thus, the effectiveness of important medical advances that seek to improve the quality of life of patients with chronic diseases is threatened. We report the simultaneous colonization and bacteremia by multidrug-resistant bacteria in two hemodialysis patients. The first patient was colonized by carbapenem- and colistin-resistant Klebsiella pneumoniae, carbapenem-resistant Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus (MRSA). The patient had a bacteremia by MRSA, and molecular typing methods confirmed the colonizing isolate was the same strain that caused infection. The second case is of a patient colonized by extended-spectrum beta-lactamases (ESBL)-producing Escherichia coli and carbapenem-resistant Pseudomonas aeruginosa. During the follow-up period, the patient presented three episodes of bacteremia, one of these caused by ESBL-producing E. coli. Molecular methods confirmed colonization by the same clone of ESBL-producing E. coli at two time points, but with a different genetic pattern to the strain isolated from the blood culture. Colonization by multidrug-resistant bacteria allows not only the spread of these microorganisms, but also increases the subsequent risk of infections with limited treatments options. In addition to infection control measures, it is important to establish policies for the prudent use of antibiotics in dialysis units.

Post-antibiotic era in hemodialysis? Two case reports of simultaneous colonization and bacteremia by multidrug-resistant bacteria / Era pós-antibiótica em hemodiálise? Relato de dois casos de colonização simultânea e bacteremia por bactérias multirresistentes

ABSTRACT The emergence of resistance mechanisms not only limits the therapeutic options for common bacterial infections but also worsens the prognosis in patients who have conditions that increase the risk of bacterial infections. Thus, the effectiveness of important medical advances that seek to improve the quality of life of patients with chronic diseases is threatened. We report the simultaneous colonization and bacteremia by multidrug-resistant bacteria in two hemodialysis patients. The first patient was colonized by carbapenem- and colistin-resistant Klebsiella pneumoniae, carbapenem-resistant Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus (MRSA). The patient had a bacteremia by MRSA, and molecular typing methods confirmed the colonizing isolate was the same strain that caused infection. The second case is of a patient colonized by extended-spectrum beta-lactamases (ESBL)-producing Escherichia coli and carbapenem-resistant Pseudomonas aeruginosa. During the follow-up period, the patient presented three episodes of bacteremia, one of these caused by ESBL-producing E. coli. Molecular methods confirmed colonization by the same clone of ESBL-producing E. coli at two time points, but with a different genetic pattern to the strain isolated from the blood culture. Colonization by multidrug-resistant bacteria allows not only the spread of these microorganisms, but also increases the subsequent risk of infections with limited treatments options. In addition to infection control measures, it is important to establish policies for the prudent use of antibiotics in dialysis units.

RESUMO O surgimento de mecanismos de resistência não apenas limita as opções terapêuticas para infecções bacterianas comuns, mas também piora o prognóstico em indivíduos com condições que aumentam o risco de infecções bacterianas. Assim, a eficácia de importantes avanços médicos que buscam melhorar a qualidade de vida de pacientes com doenças crônicas está ameaçada. Relatamos a colonização e bacteremia simultâneas por bactérias multirresistentes em dois pacientes em hemodiálise. O primeiro paciente foi colonizado por Klebsiella pneumoniae resistente a carbapenem e colistina, Pseudomonas aeruginosa resistente a carbapenem e Staphylococcus aureus resistente a meticilina (MRSA). O paciente apresentou bacteremia por MRSA, e os métodos de tipagem molecular confirmaram que o isolado colonizador era a mesma cepa que estava causando infecção. O segundo caso é de um paciente colonizado por Escherichia coli produtora de beta-lactamases de espectro estendido (ESBL) e Pseudomonas aeruginosa resistente ao carbapenem. Durante o período de seguimento, o paciente apresentou três episódios de bacteremia, um deles causado por E. coli produtora de ESBL. Os métodos moleculares confirmaram a colonização pelo mesmo clone de E. coli produtora de ESBL em dois momentos, mas com um padrão genético diferente da cepa isolada da hemocultura. A colonização por bactérias multirresistentes aumenta o potencial não apenas da disseminação desses microrganismos, mas também do risco subsequente de infecções com opções limitadas de tratamentos. Além das medidas de controle de infecção, é importante estabelecer políticas para o uso prudente de antibióticos nas unidades de diálise.