RESUMO
Background: Antibiotic-dependent pathogenic bacteria are sporadically isolated from patients that received prolonged antibiotic treatments. Evolution of antibiotics dependence and its clinical implications are scarcely studied. Materials & methods: A linezolid-dependent Staphylococcus aureus strain was isolated from a cystic fibrosis patient. A draft genome sequence was obtained and searched for known antibiotics resistance determinants and virulence factors. Results: The genome was assembled into 79 contigs for a total of 2.83 Mbp. This strain is a sequence type 5 methicillin-resistant Staphylococcus aureus with a type I SCCmec cassette also conserving the Panton-Valentine leukocidin. The G2576T substitution, conferring linezolid resistance, was harbored by all five copies of the 23S rRNA. Conclusion: The linezolid-dependent strain is related to a strain circulating in Latin America that acquired a mutation conferring linezolid resistance.
Assuntos
Antibacterianos/farmacologia , Fibrose Cística/microbiologia , Genoma Bacteriano , Linezolida/farmacologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Criança , Feminino , Humanos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacosRESUMO
Secondary acute myeloid leukemia is a very rare complication in patients with solid organ transplantation. We report a 62 years old female who received a right single lung allograft for idiopathic pulmonary fibrosis. Her immunosuppression scheme consisted in prednisone, azathioprine, and tacrolimus. Two years after the transplantation, she presented with progressive pancytopenia. Bone marrow aspiration was informed as a M4 acute myeloid leukemia, confirmed by flow cytometry. Cytogenetic study was complex, including alterations in chromosome 5. A secondary acute myeloid leukemia was diagnosed. The patient developed nosocomial pneumonia and died a few days after the diagnosis, without specific treatment. The pathogenesis of acute myeloid leukemia is probably related to the intensive exposure to immunosuppressant, especially azathioprine, in these patients.
Assuntos
Imunossupressores/efeitos adversos , Leucemia Mieloide Aguda/etiologia , Transplante de Pulmão/efeitos adversos , Azatioprina/efeitos adversos , Medula Óssea/patologia , Cromossomos Humanos Par 5 , Evolução Fatal , Feminino , Humanos , Leucopenia/complicações , Pessoa de Meia-Idade , Pancitopenia/complicações , Tacrolimo/efeitos adversosRESUMO
Secondary acute myeloid leukemia is a very rare complication in patients with solid organ transplantation. We report a 62 years old female who received a right single lung allograft for idiopathic pulmonary fibrosis. Her immunosuppression scheme consisted in prednisone, azathioprine, and tacrolimus. Two years after the transplantation, she presented with progressive pancytopenia. Bone marrow aspiration was informed as a M4 acute myeloid leukemia, confirmed by flow cytometry. Cytogenetic study was complex, including alterations in chromosome 5. A secondary acute myeloid leukemia was diagnosed. The patient developed nosocomial pneumonia and died a few days after the diagnosis, without specific treatment. The pathogenesis of acute myeloid leukemia is probably related to the intensive exposure to immunosuppressant, especially azathioprine, in these patients.