mcr-1-carrying Enterobacteriaceae isolated from companion animals in Brazil / Enterobacteriaceae portadora de mcr-1 em isolados clínicos de animais de companhia: primeiro relato no Brasil

Plasmid-mediated polymyxin resistance was first described in 2015, in China, in Escherichia coli carrying the mcr-1 (Mobile Colistin Resistance-1) gene. Since then, it has become a major public health challenge worldwide, representing a major threat to human and animal health. In addition, there are still few reports on the prevalence of mcr-1 in Enterobacteriaceae isolated from humans, animals and food. Therefore, the purpose of the study was to investigate the occurrence of the mcr-1 gene in bacterial isolates with phenotypic resistance to polymyxin B obtained from clinical specimens of companion animals. Phenotypic resistance to polymyxin B were determined by broth microdilution and the susceptibility profile to other antimicrobials (amikacin, amoxicillin/clavulanate, ampicillin, ampicillin/sulbactam, aztreonam, cefazolin, cefepime, cefotaxime, cefoxitin, ceftazidime, ceftriaxone, chloramphenicol, ciprofloxacin, doxycycline, ertapenem, gentamicin, imipenem, marbofloxacin, meropenem, phosphomycin, piperacillin/tazobactam, tetracycline, ticarcillin/clavulanate, tobramycin and trimethoprim/sulfamethoxazole) by disc-diffusion agar method. The extraction of bacterial DNA was performed via heat shock followed by spectrophotometric evaluation. To verify the presence of mcr-1, the Polymerase Chain Reaction was employed using specific primers, followed by agarose gel electrophoresis. The positive isolates had the corresponding amplicons sequenced. In this study, there were identified the first isolates of Escherichia coli, Klebsiella spp. and Enterobacter spp. carrying the mcr-1 gene derived from specimens of companion animals in Brazil. Our results suggest the dissemination of resistance to polymyxins in the community and the environment, highlighting the need for surveillance and optimized treatment guidelines.(AU)

A resistência à polimixina mediada por plasmídeo teve sua primeira descrição em 2015, na China, em Escherichia coli portadora do gene mcr-1 (Mobile Colistin Resistance-1) e a partir de então tornou-se um grande desafio para a saúde pública em todo o mundo, constituindo uma grande ameaça à saúde humana e animal. Além disso, ainda existem poucos relatos sobre a prevalência de mcr-1 em Enterobacteriaceae isoladas de humanos, animais e alimentos. Sendo assim, o objetivo do estudo foi investigar a ocorrência do gene mcr-1 em isolados bacterianos com resistência fenotípica à polimixina B, oriundos de materiais clínicos de animais de companhia. A resistência fenotípica à polimixina B foi determinada por microdiluição em caldo e o perfil de sensibilidade aos demais antimicrobianos (amicacina, amoxicilina/clavulanato, ampicilina, ampicilina/sulbactam, aztreonam, cefazolina, cefepime, cefotaxima, cefoxitina, ceftazidima, ceftriaxona, cloranfenicol, ciprofloxacina, doxiciclina, ertapenem, gentamicina, imipinem, marbofloxacino, meropenem, fosfomicina, piperacilina/tazobactam, tetraciclina, ticarcilina/clavulanato, tobramicina sulfametoxazol/trimetoprim) foram determinados pelo método disco difusão. A extração do DNA bacteriano foi realizada via choque térmico, seguido de avaliação espectrofotométrica. Para a verificação da presença do mcr-1 foi utilizada a Reação em Cadeia da Polimerase com emprego de iniciadores específicos, seguida de eletroforese em gel de agarose. Os isolados positivos tiveram os correspondentes amplicons sequenciados. Nesse estudo foram identificados os primeiros isolados de Escherichia coli, Klebsiella spp. e Enterobacter spp. portadores do gene mcr-1 derivados de espécimes de animais de companhia no Brasil. Este estudo sugere a disseminação da resistência às polimixinas na comunidade e no meio ambiente, destacando a necessidade de vigilância e diretrizes otimizadas de tratamento.(AU)

Falsa reactividad serológica en gestantes portadoras sanas de sicklemia / False serologic reactivity in healthy pregnant women with sickle cell anemia

Se presenta el caso de una embarazada perteneciente a un consultorio médico de familia del Policlínico Flores Betancourt, municipio Artemisa; la cual desconocía su estado de portadora sana de Hemoglobina S, con resultados serológicos débil reactivos durante toda su gestación y aún después de esta, sin elementos clínicos ni epidemiológicos que hicieran considerar una sífilis en el embarazo. Se procedió a estudiar las causas agudas y crónicas, más conocidas en nuestro medio como falsas reactivas, arribándose a conclusiones novedosas, hasta ahora no referidas en reportes nacionales o internacionales, con respecto a la relación existente entre el estado de portador sano de siclemia y el resultado serológico Falso Reactivo(AU)

The case of a pregnant woman is presented here. She was patient of a family doctor's office at Flores Betancourt Polyclinic in Artemisa municipality. This patient did not know her state of healthy carrier of Hemoglobin S, with weak reactive serologic results throughout her pregnancy and even afterwards. No clinical or epidemiological elements would lead to consider syphilis in pregnancy. The best known acute and chronic causes in our environment were studied as false reactive, reaching to new findings, so far not referred in national or international reports, regarding the relationship between the state of healthy carrier of sicklemia and false reagent serology(AU)

Polimorfismos intragénicos de los genes de los factores VIII y IX y su utilidad en el diagnóstico indirecto de portadoras de hemofilias A y B / Intragenic polymorphisms of factor VIII and IX genes and their utility in the indirect diagnosis of carriers of haemophilias A and B

Las Hemofilias A y B se consideran enfermedades hereditarias ligadas al sexo debidas a mutaciones en los genes que codifican para los factores VIII y IX respectivamente, ocasionando deficiencia en los niveles de la concentración plasmática de estas proteínas y cuyos roles son los de participar activamente en el mecanismo de la coagulación sanguínea. Se han reportado diversas mutaciones responsables de la alteración de estos genes; razón por la cual resulta poco práctico la aplicación de un método de diagnóstico molecular directo para la identificación de mujeres portadoras, por ello, una estrategia diagnóstica apropiada es el análisis indirecto de polimorfismos ligados al gen. El objetivo de este trabajo fue identificar mujeres portadoras en diversas familias con antecedentes de HA y HB residentes del estado Zulia, en Venezuela, caracterizando polimorfismos intragénicos de los genes del factor VIII y factor IX, los cuales permitieron asignar haplotipos y diagnosticar o descartar el estado portador al 95 por ciento de las mujeres que requerían el estudio para HA y al 100 por ciento para HB.

Haemophilia A and B are considered sex-linked inherited diseases caused by mutations in genes that encode factors VIII and IX, respectively. This results in the deficiency of these proteins plasma levels which are actively involved in the mechanism of blood coagulation. It has been reported that several mutations are responsible for the alteration of these genes, which is why the application of a molecular diagnostic method for the direct identification of female carriers is impractical. An appropriate diagnostic strategy is the indirect analysis of polymorphisms linked to the gene. The aim of this study was to identify female carriers in different families with history of HA and HB that live in Zulia State, Venezuela, characterizing intragenic gene polymorphisms of the clotting factors VIII and IX, which helped to identify and assign haplotypes, to diagnose or to exclude the carrying condition, to 95 percent of women who were needing the study for HA and to 100 percent for HB.