Emerging Trichosporon asahii in elderly patients: epidemiological and molecular analysis by the DiversiLab system.

Trichosporon asahii has been recognized as an emerging opportunistic agent for invasive infections, mainly in immunocompromised patients. Urinary tract infections by this pathogen may also occur, especially in patients with urinary obstruction or those undergoing vesical catheterization and antibiotic treatment. Many outbreaks of Trichosporon spp. have been detected after urinary catheter manipulations. We report the molecular-epidemiological characterization of T. asahii in our institution using the DiversiLab system for the molecular strain typing and compare three different methods for susceptibility testing. Our results present T. asahii as an emergent pathogen in elderly patients with urinary drainage devices that can be adequately treated with triazoles, with voriconazole being the most active. Broth dilution and Vitek 2 had good concordance, while Etest showed more discrepancies. In addition, the DiversiLab system for clonal strain typing may be a useful tool for fast and accurate management of nosocomial outbreaks.

Nosocomial infection by VIM-2 metallo-beta-lactamase-producing Pseudomonas putida.

Nosocomial infections caused by multidrug-resistant and carbapenem-resistant Pseudomonas putida isolates have been reported occasionally in severely ill or immunocompromised patients. Here we report the microbiological characteristics of what are believed to be the two first carbapenem-resistant VIM metallo-beta-lactamase (MBL)-producing P. putida strains in Spain, which were isolated from patients at the University Hospital Complex of Santiago de Compostela. Both patients were immunocompromised with severe underlying diseases and had been hospitalized for more than 15 days. One of them had previously been treated with a broad-spectrum therapy. Antimicrobial susceptibility testing showed that both strains were resistant to piperacillin/tazobactam, ceftazidime, cefepime, imipenem, meropenem, gentamicin, tobramycin, aztreonam, trimethoprim/sulfamethoxazole and ciprofloxacin, but sensitive to amikacin and colistin. For both isolates PCR and sequencing was positive for the bla(VIM-2) gene. Fingerprinting analysis revealed these were two different strains. One patient recovered clinically and one died; no direct link could be established between the isolation of P. putida and death. Our data expose the emergence of multidrug-resistant P. putida VIM-2 MBL, probably arising by independent horizontal transfer of resistance genes. So, although P. putida is not frequently isolated, it may survive easily in the hospital setting and occasionally cause difficult-to-treat nosocomial infections in severely ill patients.

Bacteriemia por Flavimonas oryzihabitans en un paciente no neutropénico con enfermedad cardiaca / Flavimonas oryzihabitans bacteriemia in a non-neutropenic patient with cardiac illness

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[Diarrhea caused by adenovirus and astrovirus in hospitalized immunodeficient patients]. / Diarrea por adenovirus y astrovirus en pacientes inmunodeficientes hospitalizados.

BACKGROUND: Acute or chronic diarrheal illness are common complications in immunosuppressed patients such as human immunodeficiency virus (HIV)-infected, bone marrow or solid organ transplanted patients and those with leukaemias or other immune deficiency disorders. Due to the importance of recognizing the feasible etiologies of diarrhea in order to give the proper antimicrobial chemotherapy or to avoid a misdiagnosis of rejection in the case of transplanted patients, we have investigated adenovirus and astrovirus antigen in faeces from different immunosuppressed patients. PATIENTS AND METHODS: Stool samples from 258 immunodeficient patients hospitalized at University Hospital Complex of Santiago of Compostela with acute or persistent diarrhea were collected between 1997-99 and assayed for astrovirus and adenovirus antigen. Viral antigen was detected by EIA. Other common enteric pathogens were also assayed. RESULTS: Adenovirus antigen was positive in 5 cases (2%) and astrovirus antigen in 12 cases (5%). The most commonly patients infected was those with haematologic disorders and premature infants. HIV-infected patients were positive for astrovirus antigen in 3 cases. The majority of the cases were related with intestinal bacterial diseases or other circumstances, such as Clostridium difficile infection, both associated with prolonged antimicrobial therapy. CONCLUSIONS: Astrovirus and adenovirus have to be considered as enteropathogens specially in immunocompromised hospitalized patients. An accurate diagnosis about diarrhea etiology is advisable in order to give a specific antimicrobial therapy, when it be necessary, or to avoid a misdiagnosis of rejection, in transplanted patients.

Stomatococcus mucilaginosus septicemia in a patient with acute lymphoblastic leukaemia.

A 16-year-old patient with acute lymphoblastic leukaemia which had relapsed for the third time developed clinical signs and symptoms of septicemia during a period of neutropenia. The patient had signs of oral mucositis, and Stomatococcus mucilaginosus was isolated from blood cultures. The patient responded well to antibiotic therapy. The biochemical characteristics and antimicrobial susceptibility patterns of 68 other pharyngeal isolates of Stomatococcus mucilaginosus from immunocompromised patients are presented.

[Neonatal sepsis: epidemiologic indicators and relation to birth weight and length of hospitalization time]. / Sepsis neonatal: indicadores epidemiológicos en relación con el peso del recién nacido y el tiempo de hospitalización.

OBJECTIVE: All cases of neonatal septicemia among neonates admitted to the neonatal unit in the pediatric department (CHUS) in Santiago de Compostela between 1992 and 1995 were studied. Our aims were: 1) To assess the incidence and microbial epidemiology. 2) To study the incidence of coagulase-negative staphylococci (CONS) sepsis stratified according to birth weight and gestational age. 3) To assess the incidence density of sepsis (IDS) and 4) To analyze the associated mortality. PATIENTS AND METHODS: One hundred eighteen episodes of sepsis in 103 neonates which fulfilled clinical and laboratory criteria with positive blood cultures were included in this study. Between the years of 1992 and 1995 there were 318 neonates suspect of having sepsis among the 2,083 who were admitted to the unit during this period and which came from our own maternity department, as well as other centers. RESULTS: In this period there were 10,457 live births in our maternity department. The annual incidence of sepsis was 6/1000 live births. Early onset sepsis was observed in 2.5/1000 live births (26 cases) and the occurrence of late onset increased to 3.5/1000 live births (36 cases). Neonatal sepsis was confirmed in 103 neonates (4.9%) corresponding to 118 episodes of sepsis. S. epidermidis was the most frequent agent isolated in blood cultures (38.1%). The highest incidence of sepsis caused by S. epidermidis was observed in neonates below 1500 g (12.1%) and less than 32 weeks gestational age (13.4%). The incidence was lower in those whose birth weights were more than 2500 g (1.9%) and > 37 weeks of gestational age (1.6%), p < 0.001. Overall mortality due to sepsis was 0.7% and increased to 5.0% among hospitalized newborns with birth weights below 1500 g. The average IDS stratified in three groups of birth weight and gestational age was 18 sepsis work-ups per 1000 patient-days of hospitalization, the lowest IDS 12.9/1000 was found in neonates whose birth weights were between 1501 g and 2500 g in comparison with neonates who weighted more than 2500 g (21.5/1000), p < 0.05, and very similar to the IDS found in the intermediate group of gestational age (13.1/1000). CONCLUSIONS: S. epidermidis and other CONS are the main agents causing sepsis in hospitalized neonates, although there is a decreasing trend of incidence (-71.1%) between the years 1992 and 1995 (5.0% vs 1.5%). Gram-negative organisms and S. agalactiae played a minor role as agents causing sepsis even though S. agalactiae is the most important agent in early onset sepsis. Overall mortality associated with sepsis (7/1000 live births) is in or under the average range of international statistics. Indexes of IDS are more valuable as epidemiological tools in assessing septicemia than the simple attack rate because they have taken into consideration the length of stay, number of hospitalized newborns, as well as the number of positive sepsis work-ups in the calculating process.

Heparin inhibits Pseudomonas adherence to soft contact lenses.

Adherence of bacteria to the surface of contact lenses may play an important role in contact lens intolerance and corneal infections. To decrease the capability of bacteria to adhere to contact lenses we incubated two types of soft contact lenses with two strains of Pseudomonas aeruginosa (serotypes 0:11 and 0:8) at a concentration of 5 x 10(7) c.f.u./ml for 12 hours. When heparin was added to the medium at a concentration of 1000 IU/ml the numbers of bacteria adhering to the contact lenses were significantly fewer than in the controls (p < 0.005). Our results suggest that heparin, either included in contact lens solutions or bonded to the surface of the contact lens, may decrease contact-lens-related morbidity.

Lack of accumulation of exogenous adenylyl dihydrostreptomycin by whole cells or spheroplasts of Escherichia coli.

Accumulation of purified adenylylated dihydrostreptomycin (DHS-AMP) was examined in two strains of Escherichia coli. E. coli JSRO-N was plasmid free and aminoglycoside (AG) susceptible; E. coli JSRO-N(pSAD1) contained a plasmid-encoded AG adenylyltransferase which modifies DHS and streptomycin and confers resistance to both of these drugs. Although both whole cells and spheroplasts of JSRO-N accumulated free DHS, we were not able to demonstrate uptake of DHS-AMP by this strain. Whole cells and spheroplasts of JSRO-N(pSAD1) accumulated DHS at a much slower rate than that observed in JSRO-N. This was presumably due to the activity of the adenylyltransferase in JSRO-N(pSAD1). However, this low rate of accumulation of DHS was still higher than the uptake of DHS-AMP by either JSRO-N or JSRO-N(pSAD1). Thus, the rate of accumulation of DHS-AMP was even lower than that of DHS during the slow, initial, energy-dependent phase of AG uptake seen in JSRO-N(pSAD1). We also found that when either JSRO-N or JSRO-N(pSAD1) was incubated with barely inhibitory or subinhibitory concentrations of DHS, rapid uptake of DHS could be stimulated by the addition of an inhibitory concentration of another AG, such as amikacin. Uptake of DHS-AMP could not be similarly enhanced by the addition of amikacin. Our results indicate that DHS-AMP is not accumulated by whole cells or spheroplasts of E. coli. These results are consistent with the postulated intracellular location of AG-modifying enzymes.