RESUMO
BACKGROUND: Shigellosis is a global human health problem causing an important morbidity among travellers returning from tropical areas. This study was aimed to describe the evolution of antimicrobial resistance profile in Shigella spp. isolated between the years 1995-2010 in patients with traveller's diarrhoea (TD) returning from tropical areas. METHODS: The levels of antimicrobial resistance were tested in a total of 191 Shigella spp. isolated during the period from 1995 to 2010. RESULTS: A decrease of cases of diarrhoea caused by Shigella has been observed in recent years. A wide spectrum of antibiotic resistance was observed among Shigella spp. These isolates showed high levels of resistance to tetracycline (84%), co-trimoxazole (75.5%), and ampicillin (45.5%). The resistance was low to ciprofloxacin (2.1%), azithromycin (3.9%) and furazolidone (8.4%). According to the period, in the case of ampicillin, amoxicillin plus clavulanic acid, chloramphenicol, values of resistance were significantly decreasing from 1995-2000 to 2001-2010, (62.5% vs. 28.4%, 19.8% vs. 6.6%, 23.4 vs. 10.4%, respectively). Meanwhile in nalidixic acid and tetracycline the evolution of resistance has increased over time. CONCLUSIONS: A decrease in the isolation number of Shigella spp. causing TD has been observed. Differential trends in the evolution of the levels of resistance to the tested antibacterial agents have been observed.
Assuntos
Antibacterianos/farmacologia , Diarreia/microbiologia , Disenteria Bacilar/microbiologia , Shigella/efeitos dos fármacos , Viagem/estatística & dados numéricos , Diarreia/epidemiologia , Farmacorresistência Bacteriana , Disenteria Bacilar/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Shigella/isolamento & purificação , Espanha/epidemiologia , Medicina de ViagemRESUMO
Neutralizing antibody (nAb) activity during the course of natural infection is believed to be crucial to combating virus propagation. The aim of this study was to measure the impact of nAb response on HCV early kinetics and genetic evolution in the liver transplantation (LT) setting. A cohort of 28 patients undergoing LT for HCV-related cirrhosis was included in the study. Viral load, nAb titers and hypervariable region 1 (HVR1) sequences were determined in serum samples obtained before and at different time points after LT. Serum nAb titers were assessed using HCV pseudoparticles (HCVpp). HVR1 sequences were obtained by direct sequencing. Patients were classified according to viral kinetic patterns (plateau or increasing), during the first week after LT. All patients demonstrated high titers of nAbs before LT, although this was not associated with early kinetic patterns or HVR1 evolution during the first week after LT. We found that in patients with plateau HCV early kinetics, the virus required adaptive mutations, while in those with increasing viral loads, the HVR1 region remained largely conserved (p = 0.015). These data suggest that HCV adaptation via selection of the best-fitted variants may account for early viral kinetics following LT.
Assuntos
Anticorpos Neutralizantes/imunologia , Formação de Anticorpos/imunologia , Anticorpos Anti-Hepatite C/imunologia , Hepatite C/cirurgia , Transplante de Fígado , Adolescente , Adulto , Idoso , Reações Cruzadas , Feminino , Hepacivirus/genética , Hepatite C/genética , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , RNA Viral/genética , Transplante Homólogo , Carga Viral , Adulto JovemRESUMO
Among 200 isolates of Shigella from patients with travellers' diarrhoea, 12 isolates (four isolated in 1995-2000 and eight in 2001-2004) exhibited quinolone resistance. Nine of these isolates originated from India. These resistant isolates had at least one amino-acid substitution in GyrA. Quinolone resistance is increasing in Shigella spp. causing travellers' diarrhoea, and particularly among isolates causing diarrhoea in travellers returning from India.
