Subject(s)
Serratia marcescens/isolation & purification , Serratia marcescens/pathogenicity , Microbial Sensitivity Tests , Microbial Sensitivity Tests/instrumentation , Bacterial Typing Techniques/instrumentation , Serratia Infections/etiology , Serratia Infections/microbiology , Anti-Bacterial AgentsABSTRACT
Serratia marcescens has been reported as an organism which can cause rapidly spreading, antibiotic resistant nosocomial colonization and disease. We report here an outbreak of colonization and disease due to S. marcescens involving 53 infants admitted to the Neonatal Intensive Care Unit (NICU) of the Uberlândia Federal University Hospital, Brazil, between December, 1997, and April, 1998. Thirty-eight infants were colonized without clinical signs of infection and 15 infants had clinical disease. Five infants developed septicemia (4 cases were fatal, including the presumed index case). Seven infants developed conjunctivitis, 1 developed both sepis and conjunctivitis, 1 infant developed otitis, and 1 infant had a urinary tract infection. On univariate analysis, independent risk factors for S. marcescens clinical disease were: low birth weight (<1.500g), incubator care, use carbapenems, duration of hospitalization (maior igual que 7 days), low Apgar score, and prematurity. All the isolates of S. marcescens showed the same antimicrobial susceptibility profile. The causative strains were resistant to oxyimino-cephalosporins due to their production of extended-spectrum ß-lactamases. Cultures from the hands of the NICU health care professionals (HCWs), soap samples, ventilator reservoirs, and work and incubator surfaces failed to identify a reservoir of S. marcescens, but positive cultures were found in half of the sink drains. Containment of the outbreak was achieved by closure of the NICU new admissions, employment of strict hygienic measures, and careful nursing care of the infected and colonized infants. Rapid organism identification and initiation of control measures are important in containing such an epidemic at an early stage.
Subject(s)
Humans , Infant, Newborn , Cross Infection/epidemiology , Infection Control , Intensive Care Units, Neonatal , Drug Resistance, Microbial , Sepsis/mortality , Serratia marcescens/isolation & purification , Serratia marcescens/pathogenicity , Case-Control Studies , Environmental Pollution , Risk FactorsABSTRACT
Cytotoxin production was studied in 60 Serratia marcescens strains isolated from hospitalized patients. Association of cytotoxic activity with serotype, source of isolation and presence of plasmids was also evaluated. Thirteen of the 60 S. marcescens strains produced a cytotoxic effect of Vero cells. These strains were isolated from distinct clinical sources and classified into seven different serotypes (O1:H7; O4:NM; O10:NT; O19:NM; O6,14:H4; O6,14:NM and O6,14:H1). No relationship was observed between cytotoxic activity and clinical source or serotypes of the strains. Plasmids from five cytotoxin-producing S. marcescens strains were transferred to E. Coli K12/711. The transconjugants did not exhibit cytotoxicity, indicating that the cytotoxic effect is not plasmid-mediated among these strains. Although a cytotoxic activity was demonstrated in filtrates of some S. marcescens strains, further studies should be performed to assess the role of this toxin in pathogenesis.
Subject(s)
Humans , Cytotoxins , In Vitro Techniques , Serratia marcescens/isolation & purification , Serratia marcescens/pathogenicity , Vero Cells/pathologyABSTRACT
El objetivo del presente trabajo es la exposición de lo que se considera el primer caso de peritonitis en un paciente con diálisis peritoneal continua ambulatoria (DPCA) -por insuficiencia renal crónica terminal-causada por Serratia marcescens y tratado exitosamente con carbenicilina. Se trata de un bacilo gramnegativo, móvil, aerobio, miembro de la división Klebsiella-Enterobacter-Serratia, entre la familia enterobacteriaceae. La Serratia contrasta con otros bacilos enterobacteriaceos en que no es huésped habitual del tracto digestivo y se adquiere por contaminación iatrógena como manipulación genitourinaria, diálisis peritoneal, hemodialisis y punción lumbar. Su tratamiento antibiótico es difícil pues presenta gran resistencia medicamentosa por plásmidos
Subject(s)
Middle Aged , Humans , Male , Female , Peritonitis/etiology , Serratia marcescens/pathogenicity , Carbenicillin/therapeutic use , Gentamicins/therapeutic use , Chloramphenicol O-Acetyltransferase/therapeutic use , Dicloxacillin/administration & dosage , Glomerulonephritis/complications , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Peritoneal Dialysis, Continuous Ambulatory/adverse effects , Renal Insufficiency, Chronic/etiologyABSTRACT
A total of 60 nosocomial isolates of Serratia marcescens were screened for the presence of markers related to virulence, i. e., cell-bound hemolysin and production of siderophore aerobactin. No aerobactin-producing strains were found, and the incidence of cell-bound hemolysin was 97%. Hemolysin-positive (58 strains) and hemolysin-negative (2 strains) Serratia marcescens showed the same LD50 (3 x 107) bacteria) in a test of virulence for mice. These results indicate that cell-bound hemolysin is not a main factor of virulence for mice in Serratia marcescens
Subject(s)
Mice , Animals , Serratia marcescens/pathogenicity , Brazil , Cross Infection , Hemolysin Proteins , VirulenceABSTRACT
Relataram-se dois casos de úlcera corneana por Serratia marcescens após transplante de córnea. Os dois pacientes receberam córneas de um mesmo doador, conservadas por 24 horas em meio Dexsol e foram operados em hospitais diferentes, por diferentes cirurgiöes. Os dois pacientes foram retransplantados. Um deles apresentou recidiva da úlcera de córnea pr Serratia, e foi submetido a recobrimento conjuntival. O outro paciente evoluiu com opacificaçäo e vascularizaçäo do segundo enxerto. Discute-se o mau prognóstico nos casos de úlcera de córnea por Serratia marcescens e a possibilidade da córnea doadora ser a fonte de infecçäo em transplantes de córnea