Microbiological assessment of arterial allografts processed in a tissue bank.

The transmission of microbial infection through tissue allografts is one of the main risks that must be controlled in tissue banks. Therefore, microbiological monitoring controls and validated protocols for the decontamination of tissues during processing have been implemented. This study is based on the evaluation of data from microbiological cultures of arteries (mainly long peripheral arteries) processed in the tissue bank of Valencia (Spain). Donors' profile, pre- and post-disinfection tissue samples were assessed. The presence of residual antibiotics in disinfected tissues was determined and the antimicrobial potential of these tissues was tested. Our overall contamination rate was 23.69%, with a disinfection rate (after antibiotic incubation) of 87.5%. Most (76.09%) of the microbial contaminants were identified as Gram positive. Arterial allografts collected from body sites affected by prior organ removal showed higher risk of contamination. Only vancomycin was detected as tissue release. The antimicrobial effect on Candida albicans was lower than that for bacterial species. Risk assessment for microbial contamination suggested the donor's skin and the environment during tissue collection as the main sources for allograft contamination. Antibiotic-disinfected arterial allografts showed antimicrobial potential.

Method-Dependent Epidemiological Cutoff Values for Detection of Triazole Resistance in Candida and Aspergillus Species for the Sensititre YeastOne Colorimetric Broth and Etest Agar Diffusion Methods.

Although the Sensititre Yeast-One (SYO) and Etest methods are widely utilized, interpretive criteria are not available for triazole susceptibility testing of Candida or Aspergillus species. We collected fluconazole, itraconazole, posaconazole, and voriconazole SYO and Etest MICs from 39 laboratories representing all continents for (method/agent-dependent) 11,171 Candida albicans, 215 C. dubliniensis, 4,418 C. glabrata species complex, 157 C.guilliermondii (Meyerozyma guilliermondii), 676 C. krusei (Pichia kudriavzevii), 298 C.lusitaniae (Clavispora lusitaniae), 911 C.parapsilosissensu stricto, 3,691 C.parapsilosis species complex, 36 C.metapsilosis, 110 C.orthopsilosis, 1,854 C.tropicalis, 244 Saccharomyces cerevisiae, 1,409 Aspergillus fumigatus, 389 A.flavus, 130 A.nidulans, 233 A.niger, and 302 A.terreus complex isolates. SYO/Etest MICs for 282 confirmed non-wild-type (non-WT) isolates were included: ERG11 (C. albicans), ERG11 and MRR1 (C. parapsilosis), cyp51A (A. fumigatus), and CDR2 and CDR1 overexpression (C. albicans and C. glabrata, respectively). Interlaboratory modal agreement was superior by SYO for yeast species and by the Etest for Aspergillus spp. Distributions fulfilling CLSI criteria for epidemiological cutoff value (ECV) definition were pooled, and we proposed SYO ECVs for S. cerevisiae and 9 yeast and 3 Aspergillus species and Etest ECVs for 5 yeast and 4 Aspergillus species. The posaconazole SYO ECV of 0.06 µg/ml for C. albicans and the Etest itraconazole ECV of 2 µg/ml for A. fumigatus were the best predictors of non-WT isolates. These findings support the need for method-dependent ECVs, as, overall, the SYO appears to perform better for susceptibility testing of yeast species and the Etest appears to perform better for susceptibility testing of Aspergillus spp. Further evaluations should be conducted with more Candida mutants.

In vitro activity of anidulafungin in combination with amphotericin B or voriconazole against biofilms of five Candida species.

OBJECTIVES: To evaluate the in vitro activity of anidulafungin combined with amphotericin B or voriconazole against Candida spp. biofilms. METHODS: Four Candida albicans, four Candida tropicalis, four Candida glabrata, two Candida parapsilosis and two Candida orthopsilosis blood isolates were tested by the microdilution chequerboard method combined with the XTT metabolic assay. Biofilm MIC was defined as the lowest concentration producing 50% metabolic inhibition with respect to control (BMIC50). Concentrations in the combinations ranged from 1/8 × BMIC50 to 4 × BMIC50 found for each antifungal tested alone. RESULTS: Anidulafungin plus amphotericin B acted synergistically against C. albicans and C. glabrata biofilms [fractional inhibitory concentration index (FICI): 0.082-0.387], but showed no interaction against C. tropicalis, C. parapsilosis and C. orthopsilosis (FICI: 0.516-2.099). The combination of these antifungals failed to completely remove biofilms of C. albicans and C. glabrata, decreasing the metabolic activity of the biofilms up to 80% and 95%, respectively, which did not occur when each antifungal was used alone. Anidulafungin plus voriconazole showed no interaction against all isolates. Using a less stringent criterion previously proposed to define synergism (FICI < 1) and antagonism (FICI > 1.25), antagonistic interactions were found against some isolates. CONCLUSIONS: Anidulafungin with amphotericin B results in a synergistic effect against C. albicans and C. glabrata biofilms at serum concentrations of the drugs, but showed no interaction against C. tropicalis and C. parapsilosis complex. Anidulafungin plus voriconazole showed no interaction against the five Candida species assayed. Biofilms of C. tropicalis were found to be the most resistant towards the combinations assayed. The results presented may be of potential interest in the clinical setting.

Multilocus microsatellite analysis of European and African Candida glabrata isolates.

This study aimed to elucidate the genetic relatedness and epidemiology of 127 clinical and environmental Candida glabrata isolates from Europe and Africa using multilocus microsatellite analysis. Each isolate was first identified using phenotypic and molecular methods and subsequently, six unlinked microsatellite loci were analyzed using automated fluorescent genotyping. Genetic relationships were estimated using the minimum-spanning tree (MStree) method. Microsatellite analyses revealed the existence of 47 different genotypes. The fungal population showed an irregular distribution owing to the over-representation of genetically different infectious haplotypes. The most common genotype was MG-9, which was frequently found in both European and African isolates. In conclusion, the data reported here emphasize the role of specific C. glabrata genotypes in human infections for at least some decades and highlight the widespread distribution of some isolates, which seem to be more able to cause disease than others.

Multicenter study of epidemiological cutoff values and detection of resistance in Candida spp. to anidulafungin, caspofungin, and micafungin using the Sensititre YeastOne colorimetric method.

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 µg/ml for C. albicans, 0.12, 0.25, and 0.03 µg/ml for C. glabrata complex, 4, 2, and 4 µg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 µg/ml for C. tropicalis, 0.25, 1, and 0.25 µg/ml for C. krusei, 0.25, 1, and 0.12 µg/ml for C. lusitaniae, 4, 2, and 2 µg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 µg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.

Clinical validation of a multiplex real-time PCR assay for detection of invasive candidiasis in intensive care unit patients.

BACKGROUND: New techniques, such as those based on multiplex quantitative real-time PCR (MRT-PCR), can improve the detection of invasive candidiasis (IC). METHODS: We prospectively studied 63 intensive care unit patients with suspected IC and 40 healthy controls. Blood cultures and MRT-PCR were performed at day 0 and +2, +7, +14 and +21 days in all patients. In addition, ß-d-glucan (BDG) and Candida albicans germ tube antibody (CAGTA) were quantified. RESULTS: IC was confirmed in 27 patients. Colonization was significantly higher in patients with IC (96% versus 64%, P = 0.002). The sensitivity, specificity, positive predictive value and negative predictive value of MRT-PCR for the diagnosis of IC were 96.3%, 97.3%, 92.8% and 98.7%, respectively. The positive predictive value and specificity were significantly higher for MRT-PCR than for BDG and CATGA. MRT-PCR performed very well, especially in deep-seated IC (sensitivity 90.9% versus 45.4% for blood culture; P = 0.06). As regards the most appropriate clinical sample for DNA amplification, in this study whole blood and serum presented similar results. CONCLUSIONS: MRT-PCR appears to be a useful test for confirming a diagnosis of IC in critically ill patients, especially in those with deep-seated disease. Its high sensitivity and positive predictive value make it a much more efficient tool for the management of IC than other diagnostic procedures and clinical scores.

Population-based survey of filamentous fungi and antifungal resistance in Spain (FILPOP Study).

A population-based survey was conducted to investigate the epidemiology of and antifungal resistance in Spanish clinical strains of filamentous fungi isolated from deep tissue samples, blood cultures, and respiratory samples. The study was conducted in two different periods (October 2010 and May 2011) to analyze seasonal variations. A total of 325 strains were isolated in 29 different hospitals. The average prevalence was 0.016/1,000 inhabitants [corrected]. Strains were identified by sequencing of DNA targets and susceptibility testing by the European Committee for Antimicrobial Susceptibility Testing reference procedure. The most frequently isolated genus was Aspergillus, accounting for 86.3% of the isolates, followed by Scedosporium at 4.7%; the order Mucorales at 2.5%; Penicillium at 2.2%, and Fusarium at 1.2%. The most frequent species was Aspergillus fumigatus (48.5%), followed by A. flavus (8.4%), A. terreus (8.1%), A. tubingensis (6.8%), and A. niger (6.5%). Cryptic/sibling Aspergillus species accounted for 12% of the cases. Resistance to amphotericin B was found in 10.8% of the isolates tested, while extended-spectrum triazole resistance ranged from 10 to 12.7%, depending on the azole tested. Antifungal resistance was more common among emerging species such as those of Scedosporium and Mucorales and also among cryptic species of Aspergillus, with 40% of these isolates showing resistance to all of the antifungal compounds tested. Cryptic Aspergillus species seem to be underestimated, and their correct classification could be clinically relevant. The performance of antifungal susceptibility testing of the strains implicated in deep infections and multicentric studies is recommended to evaluate the incidence of these cryptic species in other geographic areas.

Wild-type MIC distributions and epidemiological cutoff values for amphotericin B, flucytosine, and itraconazole and Candida spp. as determined by CLSI broth microdilution.

Clinical breakpoints (CBPs) and epidemiological cutoff values (ECVs) have been established for several Candida spp. and the newer triazoles and echinocandins but are not yet available for older antifungal agents, such as amphotericin B, flucytosine, or itraconazole. We determined species-specific ECVs for amphotericin B (AMB), flucytosine (FC) and itraconazole (ITR) for eight Candida spp. (30,221 strains) using isolates from 16 different laboratories in Brazil, Canada, Europe, and the United States, all tested by the CLSI reference microdilution method. The calculated 24- and 48-h ECVs expressed in µg/ml (and the percentages of isolates that had MICs less than or equal to the ECV) for AMB, FC, and ITR, respectively, were 2 (99.8)/2 (99.2), 0.5 (94.2)/1 (91.4), and 0.12 (95.0)/0.12 (92.9) for C. albicans; 2 (99.6)/2 (98.7), 0.5 (98.0)/0.5 (97.5), and 2 (95.2)/4 (93.5) for C. glabrata; 2 (99.7)/2 (97.3), 0.5 (98.7)/0.5 (97.8), and 05. (99.7)/0.5 (98.5) for C. parapsilosis; 2 (99.8)/2 (99.2), 0.5 (93.0)/1 (90.5), and 0.5 (97.8)/0.5 (93.9) for C. tropicalis; 2 (99.3)/4 (100.0), 32 (99.4)/32 (99.3), and 1 (99.0)/2 (100.0) for C. krusei; 2 (100.0)/4 (100.0), 0.5 (95.3)/1 (92.9), and 0.5 (95.8)/0.5 (98.1) for C. lusitaniae; -/2 (100.0), 0.5 (98.8)/0.5 (97.7), and 0.25 (97.6)/0.25 (96.9) for C. dubliniensis; and 2 (100.0)/2 (100.0), 1 (92.7)/-, and 1 (100.0)/2 (100.0) for C. guilliermondii. In the absence of species-specific CBP values, these wild-type (WT) MIC distributions and ECVs will be useful for monitoring the emergence of reduced susceptibility to these well-established antifungal agents.

Voriconazole inhibits biofilm formation in different species of the genus Candida.

OBJECTIVES: To determine the ability of voriconazole to inhibit the formation of biofilms. METHODS: A total of 38 blood isolates of Candida spp. (8 Candida albicans, 10 Candida tropicalis, 10 Candida glabrata, 7 Candida parapsilosis sensu stricto and 3 Candida orthopsilosis) and C. albicans ATCC 90028 and ATCC 64548 were assessed. Biofilm formation was quantified using XTT reduction assays. The inhibition of biofilm formation was determined (i) in the presence of 0.06 and 0.25 mg/L voriconazole, and (ii) on surfaces previously coated with 0.06, 0.25, 1, 4 and 16 mg/L voriconazole. RESULTS: Voriconazole reduced biofilm formation under both conditions, the extent depending on the species, isolate and drug concentration. In the presence of 0.25 mg/L, the highest reduction was found for C. parapsilosis (79% ±â€Š8.6%), followed by C. albicans (64.5% ±â€Š6.3%), C. tropicalis (53.3% ±â€Š13.1%) and C. glabrata (23.8% ±â€Š11.2%). This reduction was significant (P < 0.05) for all isolates tested. After coating the wells with voriconazole, biofilm formation was reduced in all Candida spp. examined, C. albicans being the species with the highest reduction (68.8% with 16 mg/L) and C. parapsilosis complex and C. glabrata the lowest. CONCLUSIONS: As voriconazole reduces biofilm formation it may be a good candidate for the prevention of Candida biofilm-related infections although further studies using voriconazole-impregnated catheter tubing or prostheses are required to confirm these results.

Impact of Aspergillus spp. isolation in the first 24 hours of admission in critically ill patients with severe influenza virus pneumonia.

OBJECTIVE: To determine the incidence and impact of Aspergillus spp. isolation (AI) on ICU mortality in critically ill patients with severe influenza pneumonia during the first 24h of admission. DESIGN: Secondary analysis of an observational and prospective cohort study. SETTING: ICUs voluntary participating in the Spanish severe Influenza pneumonia registry, between June 2009 and June 2019. PATIENTS: Consecutive patients admitted to the ICU with diagnosis of severe influenza pneumonia, confirmed by real-time polymerase chain reaction. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Incidence of AI in respiratory samples. Demographic variables, comorbidities, need for mechanical ventilation and the presence of shock according at admission. Acute Physiology and Chronic Health Evaluation II (APACHE II) scale calculated on ICU admission. RESULTS: 3702 patients were analyzed in this study. AI incidence was 1.13% (n=42). Hematological malignancies (OR 4.39, 95% CI 1.92-10.04); HIV (OR 3.83, 95% CI 1.08-13.63), and other immunosuppression situations (OR 4.87, 95% CI 1.99-11.87) were factors independently associated with the presence of Aspergillus spp. The automatic CHAID decision tree showed that hematologic disease with an incidence of 3.3% was the most closely AI related variable. Hematological disease (OR 2.62 95% CI 1.95-3.51), immunosuppression (OR 2.05 95% CI 1.46-2.88) and AI (OR 3.24, 95% CI 1.60-6.53) were variables independently associated with ICU mortality. CONCLUSIONS: Empirical antifungal treatment in our population may only be justified in immunocompromised patients. In moderate-high risk cases, active search for Aspergillus spp. should be implemented.

Correction to: Early Stepdown From Echinocandin to Fluconazole Treatment in Candidemia: A Post Hoc Analysis of Three Cohort Studies.

[This corrects the article DOI: 10.1093/ofid/ofab250.].

Risk assessment of arterial allograft contamination from tissue donors colonized by Candida auris.

BACKGROUND: Microbiological contamination is one of the main risks that must be controlled in tissue banking practices. For this reason, strict donor selection criteria are applied, disinfection protocols are used, and microbiological monitoring is performed at various stages. AIM: To detect Candida auris in arterial allografts and assess its origin. METHODS: Data on two multi-tissue donations with positive microbiological cultures for C. auris were analysed. Risk factors for microbiological contamination were assessed at procurement, processing and post storage. FINDINGS: C. auris was only isolated in cultures from arteries, and was not detected in cultures from cornea, musculoskeletal tissue or skin (even in the axillary-rectal sample taken from one donor). CONCLUSION: The donor's own skin was identified as the most likely source to explain the contamination of arteries by C. auris. Due to the pathogenicity of this fungus and difficulties associated with its correct identification, the implementation of measures for its detection in tissue donations is recommended.

Early Stepdown From Echinocandin to Fluconazole Treatment in Candidemia: A Post Hoc Analysis of Three Cohort Studies.

BACKGROUND: There are no clear criteria for antifungal de-escalation after initial empirical treatments. We hypothesized that early de-escalation (ED) (within 5 days) to fluconazole is safe in fluconazole-susceptible candidemia with controlled source of infection. METHODS: This is a multicenter post hoc study that included consecutive patients from 3 prospective candidemia cohorts (2007-2016). The impact of ED and factors associated with mortality were assessed. RESULTS: Of 1023 candidemia episodes, 235 met inclusion criteria. Of these, 54 (23%) were classified as the ED group and 181 (77%) were classified as the non-ED group. ED was more common in catheter-related candidemia (51.9% vs 31.5%; P = .006) and episodes caused by Candida parapsilosis, yet it was less frequent in patients in the intensive care unit (24.1% vs 39.2%; P = .043), infections caused by Nakaseomyces glabrata (0% vs 9.9%; P = .016), and candidemia from an unknown source (24.1% vs 47%; P = .003). In the ED and non-ED groups, 30-day mortality was 11.1% and 29.8% (P = .006), respectively. Chronic obstructive pulmonary disease (odds ratio [OR], 3.97; 95% confidence interval [CI], 1.48-10.61), Pitt score > 2 (OR, 4.39; 95% CI, 1.94-9.20), unknown source of candidemia (OR, 2.59; 95% CI, 1.14-5.86), candidemia caused by Candida albicans (OR, 3.92; 95% CI, 1.48-10.61), and prior surgery (OR, 0.29; 95% CI, 0.08-0.97) were independent predictors of mortality. Similar results were found when a propensity score for receiving ED was incorporated into the model. ED had no significant impact on mortality (OR, 0.50; 95% CI, 0.16-1.53). CONCLUSIONS: Early de-escalation is a safe strategy in patients with candidemia caused by fluconazole-susceptible strains with controlled source of bloodstream infection and hemodynamic stability. These results are important to apply antifungal stewardship strategies.

Comparison of anidulafungin MICs determined by the clinical and laboratory standards institute broth microdilution method (M27-A3 document) and Etest for Candida species isolates.

Anidulafungin Etest and CLSI MICs were compared for 143 Candida sp. isolates to assess essential (within 2 log(2) dilutions) and categorical agreements (according to three susceptibility breakpoints). Based on agreement percentages, our data indicated that Etest is not suitable to test anidulafungin against Candida parapsilosis and C. guilliermondii (54.4 to 82.4% essential and categorical agreements) but is more suitable for C. albicans, C. glabrata, C. krusei, and C. tropicalis (87.9 to 100% categorical agreement).

Evaluation of the Etest method for susceptibility testing of Aspergillus spp. and Fusarium spp. to three echinocandins.

We performed Etest and broth microdilution (BMD) susceptibility testing of caspofungin, micafungin and anidulafungin against 67 clinical isolates of Aspergillus spp. and 10 Fusarium spp. Minimal effective concentrations (MECs) by BMD were read after 24 h of incubation at 35 degrees C and Etest MICs were read at 24 and 48 h. MECs < or =0.25 mg/l were obtained with caspofungin for all Aspergillus spp. tested but Etest MICs were < or =1 mg/l at 24 h. The agreement between caspofungin Etest and broth microdilution was good for all Aspergillus species tested (range 82.4-100%) except for A. niger and A. glaucus at 24 h of incubation. Micafungin and anidulafungin MEC and MIC results were lower than those of caspofungin (< or =0.015 mg/l) at 24 and 48 h for all Aspergillus tested. The agreement between the methods was excellent (100%) for micafungin and anidulafungin for all Aspergillus species tested. The three echinocandins were inactive against all isolates of Fusarium spp. showing MECs and MICs >8 mg/l. The Etest method could be a suitable procedure to test the susceptibility of most Aspergillus species to caspofungin, micafungin and anidulafungin; the best agreement was at 24 h.

Identification of pathogenic yeast species by polymerase chain reaction amplification of the RPS0 gene intron fragment.

AIMS: This work focuses on the development of a method for the identification of pathogenic yeast. With this aim, we target the nucleotide sequence of the RPS0 gene of pathogenic yeast species with specific PCR primers. PCR analysis was performed with both the genomic DNA, whole cells of clinical isolates of Candida species and clinical samples. METHODS AND RESULTS: A single pairs of primers, deduced from the nucleotide sequence of the RPS0 gene from pathogenic yeast, were used in PCR analysis performed with both the genomic DNA and whole cells of clinical isolates of Candida species and clinical samples. The primers designed are highly specific for their respective species and produce amplicons of the expected sizes and fail to amplify any DNA fragment from the other species tested. The set of primers was tested successfully for the identification of yeast from colonies, blood cultures and clinical samples. These results indicate that genes containing intron sequences may be useful for designing species-specific primers for the identification of fungal strains by PCR. The sensitivity of the method with genomic DNA was evaluated with decreasing DNA concentrations (200 ng to 1 pg) and different cell amounts (10(7)-10(5) cells). CONCLUSION: The results obtained show that the amplification of RPS0 sequences may be suitable for the identification of pathogenic and other yeast species. SIGNIFICANCE AND IMPACT OF THE STUDY: Identification of Candida species using molecular approaches with high discriminatory power is important in determining adequate measures for the interruption of transmission of this yeast. The approach described in this work is based on standard technology, and it is specific, sensitive and does not involve complex and expensive equipment. Furthermore, the method developed in this work not only can be used in eight yeast species, but also provides the basis to design primers for other fungi species of clinical, industrial or environmental interest.

A clinical predictive model of candidaemia by Candida auris in previously colonized critically ill patients.

OBJECTIVES: Candida auris is an emerging multidrug-resistant fungus that has been associated with nosocomial outbreaks with high rates of mortality and transmission. The aim of this study was to perform a retrospective cohort analysis of risk factors and to build a scoring method for estimating the risk of candidaemia in colonized critically ill patients. METHODS: We performed a retrospective observational cohort study of patients aged ≥15 years colonized by C. auris in the 3-year period between March 2016 and March 2019. Epidemiological, clinical, laboratory and microbiological data were collected. We developed a predictive model for candidaemia using elastic net multivariable logistic regression techniques, assessed its discriminative capacity, and internally validated it using bootstrap resampling. RESULTS: Two-hundred and six patients were enrolled in the cohort for derivation and internal validation. Thirty-seven out of 206 patients developed candidaemia. Total parenteral nutrition was the foremost risk factor (adjusted OR 3.73); previous surgery (adjusted OR 1.03), sepsis (adjusted OR 1.75), previous exposure to antifungal agents (adjusted OR 1.17), arterial catheters (adjusted OR 1.46), central venous catheters (adjusted OR 1.21), presence of advanced chronic kidney disease (adjusted OR 1.35) and multifocal colonization (adjusted OR of unifocal colonization 0.46) were proven to be independent predictors of candidaemia in our cohort. The corresponding area under the curve (AUC) of the elastic net regularized predictive model was 0.89 (95%CI 0.826; 0.951). After performing the internal validation by generating 500 bootstrap replications, the model still showed great accuracy, with a resulting AUC of 0.84. CONCLUSION: Our study provides evidence on the independent predisposing factors for candidaemia. It may help predict its estimated risk and may identify a high-risk population that could benefit from early or prophylactic antifungal treatment after external validation in other cohorts.

Comparison of 24-hour and 48-hour voriconazole MICs as determined by the Clinical and Laboratory Standards Institute broth microdilution method (M27-A3 document) in three laboratories: results obtained with 2,162 clinical isolates of Candida spp. and other yeasts.

We evaluated the performance of the 24-h broth microdilution voriconazole MIC by obtaining MICs for 2,162 clinical isolates of Candida spp. and other yeasts; the 24-h results were compared to 48-h reference MICs to assess essential, as well as categorical, agreement. Although the overall essential agreement was 88.6%, it ranged from 96.4 to 100% for 6 of the 11 species or groups of yeasts tested. The overall categorical agreement was 93.2%, and it was above 90% for eight species. However, unacceptable percentages of very major errors (false susceptibility) were observed for Candida albicans (2.7%), C. glabrata (4.1%), C. tropicalis (9.7%), and other less common yeast species (9.8%). Since it is essential to identify potentially resistant isolates and breakpoints are based on 48-h MICs, it appears that the 24-h MIC is not as clinically useful as the 48-h reference MIC. However, further characterization of these falsely susceptible MICs for three of the four common Candida spp. is needed to understand whether these errors are due to trailing misinterpretation or if the 48-h incubation is required to detect voriconazole resistance. Either in vivo versus in vitro correlations or the determination of resistance mechanisms should be investigated.

[Breastfeeding and antiinfectious agents]. / Uso de antibióticos y lactancia materna.

Not infrequently an infection or an antibiotic treatment needed by a lactating mother leads to medical advice against breastfeeding. However, advising against breastfeeding increases morbi-mortality risk in the infant. Besides there are few anti-infectious agents not compatible with breastfeeding, and in these cases, there is usually an alternative to treat the mother's illness. Thus it is important for health professionals to be informed of best sources where to look for the best treatment for the mother compatible with breastfeeding. This article offers the reader a review of basic pharmacodynamics which influence drug use in human lactation, an alphabetically ordered list of available anti-infectious agents coded by numbers indicating risk level, and some web recommendations for the interested reader. We hope to offer the interested reader a useful tool which may prevent some cases of physician led abandonment of lactation.

Unexpected postmortem diagnosis of Acanthamoeba meningoencephalitis following allogeneic peripheral blood stem cell transplantation.

Meningoencephalitis caused by pathogenic free-living amebas is usually fatal. Only a few cases of Acanthamoeba meningoencephalitis, diagnosed at autopsy, have been reported following hematopoietic stem cell transplantation. We here report a case of Acanthamoeba meningoencephalitis following allogeneic peripheral blood stem cell transplantation with rapidly evolving neurologic symptoms that remained unexplained. Magnetic resonance imaging failed to show brain lesions and cerebrospinal fluid was negative for microbiological cultures. Definite diagnosis was an unexpected autopsy finding. As overall and teaching hospital autopsy rates are declining worldwide, we must emphasize the need of autopsy exams if we want to improve our knowledge as the best way to care for our patients.