Evaluación de la espectrometría de masas en la identificación de levaduras de interés clínico / Evaluation of mass spectrometry for the identification of clinically interesting yeasts

INTRODUCCIÓN: La identificación de levaduras se basa en el estudio de las características morfológicas, bioquímicas y nutricionales, y en la utilización de métodos moleculares. La espectrometría de masas matrix-assisted laser desorption ionization time-of-fligh (MALDI-TOF) constituye un nuevo método de identificación de microorganismos que ha demostrado gran utilidad. Nuestro objetivo ha sido evaluar este nuevo método en la identificación de levaduras. MÉTODOS: Ensayamos un total de 600 cepas aisladas de muestras clínicas pertenecientes a 9 géneros y 43 especies. La identificación se realizó mediante secuenciación de las regiones ITS del ADN ribosómico, asimilación de compuestos de carbono (ID 32C) y espectrometría de masas en un espectrómetro Microflex (Bruker Daltonics GmbH, Alemania). RESULTADOS: Un total de 569 cepas (94,8%) fueron identificadas a nivel de especie por ID 32C, y 580 (96,7%) por MALDI-TOF. La concordancia entre ambos métodos comprendió un total de 553 cepas (92,2%), elevándose al 100% en las especies de interés clínico: Candida albicans, C. glabrata, C. parapsilosis, C. tropicalis, y casi del 100% en C. krusei. MALDI-TOF identificó especies que precisan métodos moleculares: Candida dubliniensis, C. nivariensis, C. orthopsilosis y C. metapsilosis. Observamos cierta irregularidad en la identificación de levaduras formadoras de artroconidias y de basidiomicetos. CONCLUSIÓN: La espectrometría de masas MALDI-TOF es un método rápido, rentable y económico que permite la identificación de la mayoría de las levaduras aisladas en clínica, así como la diferenciación de especies estrechamente relacionadas. Sería conveniente la inclusión de más especies en su base de datos para ampliar su rentabilidad

INTRODUCTION: The aim of the study was to analyze the incidence, management and cost associated to hematological and dermatological adverse effects (AE) in chronic hepatitis C patients on triple therapy (TT) with telaprevir (TVR) or boceprevir (BOC). METHODS: An analysis was made on the data recorded on patients who started treatment with TVR or BOC associated with peginterferon alfa and ribavirin in a 12-week follow-up period. RESULTS: Fifty-three patients were included (TVR n = 36; BOC n = 17). Thrombocytopenia (83% TVR vs. 88% BOC) followed by neutropenia (89% TVR vs. 82% BOC) were the most common AE. Dermatological AE were observed in 32% of patients. Eleven patients required treatment discontinuation (all of them received TVR), and toxicity was the main reason for discontinuation (64%). The percentage of patients who required supportive treatment for management of AE was 66%. The most used supportive treatment was erythropoietin. Eight patients required emergency health care, and 2 were hospitalized due to AE. Total cost of additional supportive resources was 32,522 Euros (625 [SD = 876] Euros/patient) (TVR 759 [SD = 1,022] Euros/patient vs. BOC 349 [SD = 327] Euros/patient; P > .05). Patients with grade iii-iv toxicity required greater supportive care with higher costs, compared to patients with grade i-ii toxicity (849 [SD = 1,143] Euros/patient vs. 387 [SD = 397] Euros/patient; P = .053). CONCLUSION: The addition of new protease inhibitors to conventional treatment leads to a higher incidence of hematological AE in our study, compared to data described in clinical trials. The elevated incidence of AE involves the use of supportive care, increasing total costs of therapy

Fungemia por Trichosporon asahii en un paciente con neoplasia hematológica / Fungemia due to Trichosporon asahii in a patient with hematological malignancy

Antecedentes. La tricosporonosis es una infección oportunista debida a hongos levaduriformes del género Trichosporon. La mayoría de los casos de tricosporonosis invasiva acontecen en individuos inmunodeficientes. Caso clínico. Describimos un caso de infección diseminada por Trichosporon asahii en un paciente hematológico. Se trata de un varón de 52 años diagnosticado de leucemia linfoblástica aguda que desarrolla un cuadro febril durante el tercer ciclo de quimioterapia de inducción. A las 24 h de incubación se observó positividad en los hemocultivos extraídos, visualizándose en la tinción de Gram estructuras alargadas compatibles con elementos fúngicos. La identificación del hongo como Trichosporon asahii se llevó a cabo mediante la asimilación de compuestos de carbono y la amplificación y secuenciación de los dominios D1/D2 y la región espaciadora interna transcrita del ADN ribosómico. El hongo se aisló además de unas lesiones pustulosas que presentaba el paciente en la región pectoral. Tras tratamiento con anfotericina B, el paciente evolucionó favorablemente de las lesiones y del proceso febril. Conclusiones. Trichosporon asahii es un patógeno emergente en pacientes inmunodeprimidos y su presencia no debe ser considerada como colonización, pues existe riesgo de infección invasiva (AU)

Background. Trichosporonosis is an opportunistic infection caused by the genus Trichosporon. The majority of cases of invasive trichosporonosis occurs in immunocompromised individuals. Case report. We describe a case of disseminated infection by Trichosporon asahii in a hematology patient. A 52-year-old man diagnosed with acute lymphoblastic leukemia developed a febrile episode during the third cycle of the induction chemotherapy. The blood cultures were positive after 24 h incubation, showing elongated structures compatible with fungal elements in the Gram stain. The identification of the fungus as Trichosporon asahii was carried out by the assimilation of compounds of carbon and the amplification and sequencing of the D1/D2 domain and the internal transcribed spacer of the ribosomal DNA. The fungus was also isolated from the pustular lesions that the patient had in the chest. After treatment with amphotericin B, the patient progressed satisfactorily. Conclusions. Trichosporon asahii is an emergent pathogen in immunosupressed patients and its presence should not be considered as colonization, as there is risk of invasive infection (AU)

[Fungemia due to Trichosporon asahii in a patient with hematological malignancy]. / Fungemia por Trichosporon asahii en un paciente con neoplasia hematológica.

BACKGROUND: Trichosporonosis is an opportunistic infection caused by the genus Trichosporon. The majority of cases of invasive trichosporonosis occurs in immunocompromised individuals. CASE REPORT: We describe a case of disseminated infection by Trichosporon asahii in a hematology patient. A 52-year-old man diagnosed with acute lymphoblastic leukemia developed a febrile episode during the third cycle of the induction chemotherapy. The blood cultures were positive after 24h incubation, showing elongated structures compatible with fungal elements in the Gram stain. The identification of the fungus as Trichosporon asahii was carried out by the assimilation of compounds of carbon and the amplification and sequencing of the D1/D2 domain and the internal transcribed spacer of the ribosomal DNA. The fungus was also isolated from the pustular lesions that the patient had in the chest. After treatment with amphotericin B, the patient progressed satisfactorily. CONCLUSIONS: Trichosporon asahii is an emergent pathogen in immunosupressed patients and its presence should not be considered as colonization, as there is risk of invasive infection.

[Evaluation of mass spectrometry for the identification of clinically interesting yeasts]. / Evaluación de la espectrometría de masas en la identificación de levaduras de interés clínico.

INTRODUCTION: Identification of yeasts is based on morphological, biochemical and nutritional characteristics, and using molecular methods. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, a new method for the identification of microorganisms, has demonstrated to be very useful. The aim of this study is to evaluate this new method in the identification of yeasts. METHODS: A total of 600 strains of yeasts isolated from clinical specimens belonging to 9 genera and 43 species were tested. Identification was made by sequencing of the ITS regions of ribosomal DNA, assimilation of carbon compounds (ID 32C), and mass spectrometry on a Microflex spectrometer (Bruker Daltonics GmbH, Germany). RESULTS: A total of 569 strains (94.8%) were identified to species level by ID 32C, and 580 (96.7%) by MALDI-TOF. Concordance between both methods was observed for 553 strains (92.2%), with 100% in clinically relevant species: C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and almost 100% in C. krusei. MALDI-TOF identified species requiring molecular methods: Candida dubliniensis, C. nivariensis, C. metapsilosis and C. orthopsilosis. Some irregularities were observed in the identification of arthroconidia yeast and basidiomycetes. CONCLUSION: MALDI-TOF is a rapid, effective and economic method, which enables the identification of most clinically important yeasts and the differentiation of closely related species. It would be desirable to include more species in its database to expand its performance.

Reappraisal of the outcome of healthcare-associated and community-acquired bacteramia: a prospective cohort study.

BACKGROUND: Healthcare-associated (HCA) bloodstream infections (BSI) have been associated with worse outcomes, in terms of higher frequencies of antibiotic-resistant microorganisms and inappropriate therapy than strict community-acquired (CA) BSI. Recent changes in the epidemiology of community (CO)-BSI and treatment protocols may have modified this association. The objective of this study was to analyse the etiology, therapy and outcomes for CA and HCA BSI in our area. METHODS: A prospective multicentre cohort including all CO-BSI episodes in adult patients was performed over a 3-month period in 2006-2007. Outcome variables were mortality and inappropriate empirical therapy. Adjusted analyses were performed by logistic regression. RESULTS: 341 episodes of CO-BSI were included in the study. Acquisition was HCA in 56% (192 episodes) of them. Inappropriate empirical therapy was administered in 16.7% (57 episodes). All-cause mortality was 16.4% (56 patients) at day 14 and 20% (71 patients) at day 30. After controlling for age, Charlson index, source, etiology, presentation with severe sepsis or shock and inappropriate empirical treatment, acquisition type was not associated with an increase in 14-day or 30-day mortality. Only an stratified analysis of 14th-day mortality for Gram negatives BSI showed a statically significant difference (7% in CA vs 17% in HCA, p = 0,05). Factors independently related to inadequate empirical treatment in the community were: catheter source, cancer, and previous antimicrobial use; no association with HCA acquisition was found. CONCLUSION: HCA acquisition in our cohort was not a predictor for either inappropriate empirical treatment or increased mortality. These results might reflect recent changes in therapeutic protocols and epidemiological changes in community pathogens. Further studies should focus on recognising CA BSI due to resistant organisms facilitating an early and adequate treatment in patients with CA resistant BSI.

Epidemiological cutoff values for fluconazole, itraconazole, posaconazole, and voriconazole for six Candida species as determined by the colorimetric Sensititre YeastOne method.

In the absence of clinical breakpoints (CBP), epidemiological cutoff values (ECVs) are useful to separate wild-type (WT) isolates (without mechanisms of resistance) from non-WT isolates (those that can harbor some resistance mechanisms), which is the goal of susceptibility tests. Sensititre YeastOne (SYO) is a widely used method to determine susceptibility of Candida spp. to antifungal agents. The CLSI CBP have been established, but not for the SYO method. The ECVs for four azoles, obtained using MIC distributions determined by the SYO method, were calculated via five methods (three statistical methods and based on the MIC50 and modal MIC). Respectively, the median ECVs (in mg/liter) of the five methods for fluconazole, itraconazole, posaconazole, and voriconazole (in parentheses: the percentage of isolates inhibited by MICs equal to or less than the ECVs; the number of isolates tested) were as follows: 2 (94.4%; 944), 0.5 (96.7%; 942), 0.25 (97.6%; 673), and 0.06 (96.7%; 849) for Candida albicans; 4 (86.1%; 642), 0.5 (99.4%; 642), 0.12 (93.9%; 392), and 0.06 (86.9%; 559) for C. parapsilosis; 8 (94.9%; 175), 1 (93.7%; 175), 2 (93.6%; 125), and 0.25 (90.4%; 167) for C. tropicalis; 128 (98.6%; 212), 4 (95.8%; 212), 4 (96.0%; 173), and 2 (98.5; 205) for C. glabrata; 256 (100%; 53), 1 (98.1%; 53), 1 (100%; 33), and 1 (97.9%; 48) for C. krusei; 4 (89.2%; 93), 0.5 (100%; 93), 0.25 (100%; 33), and 0.06 (87.7%; 73) for C. orthopsilosis. All methods included ≥94% of isolates and yielded similar ECVs (within 1 dilution). These ECVs would be suitable for monitoring emergence of isolates with reduced susceptibility by using the SYO method.

[Pantoea agglomerans: a new pathogen at the neonatal intensive care unit?]. / Pantoea agglomerans: ¿un nuevo patógeno en la unidad de cuidados intensivos neonatales?

Late-onset sepsis is very frequent among preterm infants and cases due to Gram negative pathogens have elevated morbidity and mortality. Pantoea agglomerans is a Gram negative organism which has been rarely reported causing disease in humans. We present a case of P. agglomerans late-onset fulminant sepsis in a preterm newborn at a neonatal intensive care unit. Up to date none P. agglomerans sepsis has been reported among this population in our country.

Pantoea agglomerans: ¿un nuevo patógeno en la unidad de cuidados intensivos neonatales?: a new pathogen at the neonatal intensive care unit? / Pantoea agglomerans

La sepsis tardía es especialmente frecuente en los recién nacidos pretérmino, y los bacilos gramnegativos son responsables de los casos más graves con una elevada mortalidad asociada. Pantoea agglomerans es un bacilo gramnegativo que pocas veces se ha descrito como patógeno en el ser humano, menos aún en el recién nacido. Se presenta el caso clínico de un recién nacido pretérmino que sufrió una sepsis fulminante por Pantoea agglomerans en una unidad de cuidados intensivos neonatales. Hasta la fecha no se ha descrito ningún caso de sepsis por P. agglomerans en esta población en España.(AU)

Late-onset sepsis is very frequent among preterm infants and cases due to Gram negative pathogens have elevated morbidity and mortality. Pantoea agglomerans is a Gram negative organism which has been rarely reported causing disease in humans. We present a case of P. agglomerans late-onset fulminant sepsis in a preterm newborn at a neonatal intensive care unit. Up to date none P. agglomerans sepsis has been reported among this population in our country.(AU)

Pantoea agglomerans: ¿un nuevo patógeno en la unidad de cuidados intensivos neonatales?: a new pathogen at the neonatal intensive care unit? / Pantoea agglomerans

La sepsis tardía es especialmente frecuente en los recién nacidos pretérmino, y los bacilos gramnegativos son responsables de los casos más graves con una elevada mortalidad asociada. Pantoea agglomerans es un bacilo gramnegativo que pocas veces se ha descrito como patógeno en el ser humano, menos aún en el recién nacido. Se presenta el caso clínico de un recién nacido pretérmino que sufrió una sepsis fulminante por Pantoea agglomerans en una unidad de cuidados intensivos neonatales. Hasta la fecha no se ha descrito ningún caso de sepsis por P. agglomerans en esta población en España.

Late-onset sepsis is very frequent among preterm infants and cases due to Gram negative pathogens have elevated morbidity and mortality. Pantoea agglomerans is a Gram negative organism which has been rarely reported causing disease in humans. We present a case of P. agglomerans late-onset fulminant sepsis in a preterm newborn at a neonatal intensive care unit. Up to date none P. agglomerans sepsis has been reported among this population in our country.

Epidemiology and antifungal susceptibility of bloodstream fungal isolates in pediatric patients: a Spanish multicenter prospective survey.

Data on fungemia epidemiology and antifungal susceptibility of isolates from children are scarce, leading frequently to pediatric empirical treatment based on available adult data. The present study was designed to update the epidemiological, mycological, and in vitro susceptibility data on fungal isolates from children with fungemia in Spain. All fungemia episodes were identified prospectively by blood culture over 13 months at 30 hospitals. Tests of susceptibility to amphotericin B, flucytosine, fluconazole, itraconazole, posaconazole, voriconazole, anidulafungin, caspofungin, and micafungin were performed at participant institutions by a microdilution colorimetric method. New species-specific clinical breakpoints for fluconazole, voriconazole, and echinocandins were also applied. A total of 203 episodes of fungemia in 200 children were identified. A higher proportion of fungal isolates was from general wards than intensive care units (ICU). Candida parapsilosis (46.8%), Candida albicans (36.5%), Candida tropicalis (5.9%), Candida glabrata (3.9%), and Candida guilliermondii (2.5%) were the leading species. C. parapsilosis was the predominant species except in neonates. C. albicans was the most frequent in neonatal ICU settings (51.9%). Intravascular catheter (79.3%), surgery (35%), prematurity (30%), and neutropenia (11%) were the most frequent predisposing factors. Most Candida isolates (95.1%) were susceptible to all antifungals. When the new species-specific clinical breakpoints were applied, all C. parapsilosis isolates were susceptible to echinocandins except one, which was micafungin resistant. This is the largest published series of fungemia episodes in the pediatric setting. C. parapsilosis is the most prevalent species in Spain, followed by C. albicans and C. tropicalis. Resistance to azole and echinocandin agents is extremely rare among Candida species. The fluconazole resistance rate in Spain has decreased in the last 10 years.

Fungemia por Candida lipolytica: a propósito de 2 casos / Fungemia caused by Candida lipolytica: speaking of two cases

Candida lipolytica es un patógeno humano infrecuente. A continuación se presentan 2 casos de fungemia por C. lipolytica, uno de ellos en un niño de 12 años con fibrosis quística pancreática en fase avanzada y el otro en una mujer de 86 años que presentaba neoformación vesical con fibrosis peritoneal, hidronefrosis bilateral e infecciones del tracto urinario de repetición. Tras la administración de antifúngicos y la retirada del catéter, la fungemia se resolvió y los hemocultivos fueron negativos en ambos casos(AU)

Candida lipolytica has rarely been reported as a human pathogen. We observed two cases of fungemia caused by C. lipolytica, one of them in a 12-year-old child with cystic pancreatic fibrosis in advanced phase and another in a 86-year-old woman who presented vesical neoformation with peritoneal fibrosis, bilateral hydronephrosis and recurrent urinary tract infections. After antifungal treatment and catheter removal, the fungemia appeared to be finished and blood cultures were negative(AU)

[Fungemia caused by Candida lipolytica: Speaking of two cases]. / Fungemia por Candida lipolytica: a propósito de 2 casos.

Candida lipolytica has rarely been reported as a human pathogen. We observed two cases of fungemia caused by C. lipolytica, one of them in a 12-year-old child with cystic pancreatic fibrosis in advanced phase and another in a 86-year-old woman who presented vesical neoformation with peritoneal fibrosis, bilateral hydronephrosis and recurrent urinary tract infections. After antifungal treatment and catheter removal, the fungemia appeared to be finished and blood cultures were negative.

[Kodamaea ohmeri fungemia associated with surgery]. / Fungemia por Kodamaea (Pichia) ohmeri asociada a cirugía.

We report a case of fungemia caused by Kodamaea (Pichia) ohmeri associated with surgery in a patient with a history of diabetes and chronic renal failure. Kodamaea ohmeri is a yeast rarely involved in human infections. Since the first report of a case of fungemia in 1998, only thirteen cases of K. ohmeri infection have been so far described in the medical literature.

Fungemia por Kodamaea (Pichia) ohmeri asociada a cirugía / Kodamaea ohmeri fungemia associated with surgery

Presentamos un caso de fungemia por Kodamaea (Pichia) ohmeri asociadaa cirugía en una paciente diabética con insuficiencia renal crónica. Kodamaeaohmeri es una levadura que raramente causa infecciones en el ser humano.Desde el primer caso de fungemia publicado en 1998, solamente otros trececasos de infección por K. ohmeri han sido descritos en la literatura(AU)

We report a case of fungemia caused by Kodamaea (Pichia) ohmeri associatedwith surgery in a patient with a history of diabetes and chronic renal failure.Kodamaea ohmeri is a yeast rarely involved in human infections. Since the firstreport of a case of fungemia in 1998, only thirteen cases of K. ohmeri infectionhave been so far described in the medical literature(AU)

[Erythrovirus B19 infection]. / Infección por Erythrovirus B19.

Erythrovirus B19 has been associated with an expanding range of clinical disorders since its identification as the etiological agent of erythema infectiosum, or fifth disease of childhood: acute arthropathy, dermatologic manifestations, chronic anemia in immunocompromised patients, and transient aplastic crisis in individuals with underlying chronic hemolytic disorders. Furthermore, exposure to and infection by B19 virus can lead to serious complications during pregnancy, which may result in fetal anemia, spontaneous abortion, and hydrops fetalis. Consequently, the B19 immune status of pregnant women should be routinely determined. Because many immunocompromised patients with chronic anemia will respond positively to intravenous immunoglobulin therapy, laboratory confirmation of B19 infection is required. Since Erythrovirus B19 cannot be routinely grown in vitro, diagnostic methods for detecting the presence of B19 by molecular techniques or by investigating the specific immune response should be considered in clinical microbiology laboratories.

Infección por Erythrovirus B19 / Erythrovirus B19 infection

Erythrovirus B19 se ha asociado con una gran variedad de manifestaciones clínicas diferentes desde que se descubriera como agente etiológico del eritema infeccioso o quinta enfermedad infantil: artropatía aguda, manifestaciones dermatológicas diversas, anemia crónica en inmunodeprimidos y crisis aplásica transitoria, en pacientes con anemias hemolíticas crónicas. Además, la exposición y la infección por B19 durante el embarazo pueden acarrear graves complicaciones para el feto, como anemia fetal, aborto espontáneo e hydrops fetalis. Por tanto, el estado inmunitario frente al B19 debería realizarse de forma sistemática en la embarazada. Muchos pacientes inmunodeprimidos con anemia crónica responden al tratamiento con inmunoglobulina por vía intravenosa; por ello, en estos casos es de gran importancia la confirmación de la infección por el virus. Puesto que es muy difícil su cultivo in vitro, consideramos que actualmente los laboratorios de microbiología clínica deberían realizar las técnicas serológicas y los nuevos métodos de detección de ADN viral disponibles para el diagnóstico de la infección por B19

Erythrovirus B19 has been associated with an expanding range of clinical disorders since its identification as the etiological agent of erythema infectiosum, or fifth disease of childhood: acute arthropathy, dermatologic manifestations, chronic anemia in immunocompromised patients, and transient aplastic crisis in individuals with underlying chronic hemolytic disorders. Furthermore, exposure to and infection by B19 virus can lead to serious complications during pregnancy, which may result in fetal anemia, spontaneous abortion, and hydrops fetalis. Consequently, the B19 immune status of pregnant women should be routinely determined. Because many immunocompromised patients with chronic anemia will respond positively to intravenous immunoglobulin therapy, laboratory confirmation of B19 infection is required. Since Erythrovirus B19 cannot be routinely grown in vitro, diagnostic methods for detecting the presence of B19 by molecular techniques or by investigating the specific immune response should be considered in clinical microbiology laboratories