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The clinical involvement and antifungal susceptibility of Aspergillus section Circumdati are poorly known. We analyzed 52 isolates, including 48 clinical isolates, belonging to 9 species inside the section Circumdati. The whole section exhibited, by the EUCAST reference method, a poor susceptibility to amphotericin B, but species/series-specific patterns were observed for azole drugs. This underlines the interest in getting an accurate identification inside the section Circumdati to guide the choice of antifungal treatment in clinical practice.
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Antifúngicos , Aspergillus , Antifúngicos/farmacología , Pruebas de Sensibilidad Microbiana , Anfotericina B/farmacología , Azoles/farmacologíaRESUMEN
Susceptibility testing is an important tool in the clinical setting; its utility is based on the availability of categorical endpoints, breakpoints (BPs), or epidemiological cutoff values (ECVs/ECOFFs). CLSI and EUCAST have developed antifungal susceptibility testing, BPs, and ECVs for some fungal species. Although the concentration gradient strip bioMérieux Etest is useful for routine testing in the clinical laboratory, ECVs are not available for all agent/species; the lack of clinical data precludes development of BPs. We reevaluated and consolidated Etest data points from three previous studies and included new data. We defined ECOFFinder Etest ECVs for three sets of species-agent combinations: fluconazole, posaconazole, and voriconazole and 9 Candida spp.; amphotericin B and 3 nonprevalent Candida spp.; and caspofungin and 4 Aspergillus spp. The total of Etest MICs from 23 laboratories (Europe, the Americas, and South Africa) included (antifungal agent dependent): 17,242 Candida albicans, 244 C. dubliniensis, 5,129 C. glabrata species complex (SC), 275 C. guilliermondii (Meyerozyma guilliermondii), 1,133 C. krusei (Pichia kudriavzevii), 933 C. kefyr (Kluyveromyces marxianus), 519 C. lusitaniae (Clavispora lusitaniae), 2,947 C. parapsilosis SC, 2,214 C. tropicalis, 3,212 Aspergillus fumigatus, 232 A. flavus, 181 A. niger, and 267 A. terreus SC isolates. Triazole MICs for 66 confirmed non-wild-type (non-WT) Candida isolates were available (ERG11 point mutations). Distributions fulfilling CLSI ECV criteria were pooled, and ECOFFinder Etest ECVs were established for triazoles (9 Candida spp.), amphotericin B (3 less-prevalent Candida spp.), and caspofungin (4 Aspergillus spp.). Etest fluconazole ECVs could be good detectors of Candida non-WT isolates (59/61 non-WT, 4 of 6 species).
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Anfotericina B , Candida , Anfotericina B/farmacología , Antifúngicos/farmacología , Aspergillus , Caspofungina , Pruebas Antimicrobianas de Difusión por Disco , Farmacorresistencia Fúngica , Kluyveromyces , Pruebas de Sensibilidad Microbiana , Pichia , Saccharomycetales , Triazoles/farmacologíaRESUMEN
The antifungal susceptibility of Aspergillus cryptic species is poorly known. We assessed 51 isolates, belonging to seven Fumigati cryptic species, by the EUCAST reference method and the concentration gradient strip (CGS) method. Species-specific patterns were observed, with high MICs for azole drugs, except for Aspergillus hiratsukae and Aspergillus tsurutae, and high MICs for amphotericin B for Aspergillus lentulus and Aspergillus udagawae Essential and categorical agreements between EUCAST and CGS results were between 53.3 and 93.3%.
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Antifúngicos , Aspergillus , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Pruebas de Sensibilidad MicrobianaRESUMEN
Pneumocystis pneumonia (PCP) in solid organ transplant (SOT) recipients becomes rare in the immediate posttransplantation period thanks to generalized prophylaxis. We aimed to identify the predictive factors for PCP in the era of universal prophylaxis and to propose a strategy for preventing PCP beyond the first year after transplantation. In a retrospective case-control study, 33 SOT cases with PCP diagnosed between 2004 and 2010 were matched with two controls each to identify risk factors for PCP by uni- and multivariate analysis. All the patients benefited from 6 months of posttransplantation trimethoprim-sulfamethoxazole prophylaxis. Most PCP in SOT patients occurred during the second year posttransplantation (33%). By univariate analysis, age, nonuse of tacrolimus, total and CD4 lymphocyte counts, gamma-globulin concentration and cytomegalovirus (CMV) infection appeared to be PCP risk factors. In the final multivariate analysis, age (adjusted odds ratio [OR] 3.7, 95% confidence interval [CI]: 1.3-10.4), CMV infection (OR: 5.2, 95% CI: 1.8-14.7) and total lymphocyte count (OR: 3.9, 95% CI: 1.4-10.7) were found to be independently associated with PCP. The second year posttransplantation appeared to be the new period of highest risk of PCP. Age, CMV viremia and lymphocytes were the most pertinent predictive criteria to evaluate the risk of PCP in clinical practice.
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Profilaxis Antibiótica , Antifúngicos/uso terapéutico , Rechazo de Injerto/etiología , Trasplante de Órganos , Neumonía por Pneumocystis/etiología , Receptores de Trasplantes , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Estudios de Casos y Controles , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/microbiología , Femenino , Estudios de Seguimiento , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/tratamiento farmacológico , Supervivencia de Injerto , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Pneumocystis carinii , Neumonía por Pneumocystis/diagnóstico , Neumonía por Pneumocystis/tratamiento farmacológico , Complicaciones Posoperatorias , Estudios Retrospectivos , Factores de Riesgo , Donantes de TejidosRESUMEN
Due to large outbreaks observed worldwide, Candida auris has emerged as a major threat to healthcare facilities. To prevent these phenomena, a systematic screening should be performed in patients transferred from regions where the pathogen is highly endemic. In this study, we recorded and analyzed French mycologists' current knowledge and practice regarding C. auris screening and diagnosis. Thirty-six centers answered an online questionnaire. Only 11 (30.6 %) participants were aware of any systematic screening for C. auris for patients admitted to their hospital. In the case of post-admission screening, axillae/groins (n = 21), nares (n = 7), rectum (n = 9), and mouth (n = 6) alone or various combinations were the body sites the most frequently sampled. Only six centers (8.3 %) reported using a commercially available plate allowing the differentiation of C. auris colonies from that of other Candida species, while five laboratories (13.8 %) had implemented a C. auris-specific qPCR. Considering the potential impact on infected patients and the risk of disorganization in the care of patients, it is crucial to remember to biologists and clinicians the utmost importance of systematic screening on admission.
RESUMEN
Ochroconis gallopava is an emerging cause of mycosis in solid organ transplant recipients. Herein, we report a rare case of disseminated O. gallopava infection that involved lung, subcutaneous area, brain and peritoneum in a heart transplant recipient. Despite voriconazole therapy, the patient died 2 months after diagnosis.
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Ascomicetos/patogenicidad , Trasplante de Corazón/efectos adversos , Micosis/diagnóstico , Micosis/patología , Antifúngicos/uso terapéutico , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Encéfalo/microbiología , Encéfalo/patología , Resultado Fatal , Humanos , Pulmón/microbiología , Pulmón/patología , Masculino , Persona de Mediana Edad , Micosis/tratamiento farmacológico , Micosis/microbiología , Peritoneo/microbiología , Peritoneo/patología , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , VoriconazolRESUMEN
Paecilomyces lilacinus is an emerging pathogen in immunocompromised patients. We report here a case of cutaneous hyphomycosis in a 63-year-old heart transplant recipient caused by the simultaneous presence of 2 molds: Paecilomyces lilacinus and Alternaria alternata. The infection was successfully treated with local voriconazole followed by oral terbinafine.
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Alternaria , Alternariosis/microbiología , Dermatomicosis/microbiología , Trasplante de Corazón/efectos adversos , Paecilomyces , Antifúngicos/administración & dosificación , Antifúngicos/uso terapéutico , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Pirimidinas/administración & dosificación , Pirimidinas/uso terapéutico , Triazoles/administración & dosificación , Triazoles/uso terapéutico , VoriconazolRESUMEN
BACKGROUND: Cerebral aspergillosis (CA) is a life-threatening disease for which diagnosis and management remain challenging. Detailed analyses from large cohorts are lacking. METHODS: We included 119 cases of proven (n = 54) or probable (n = 65) CA diagnosed between 2006 and 2018 at 20 French hospitals. Data were collected at baseline and during follow-up. Cerebral imaging was reviewed centrally by two neuroradiologists. RESULTS: The most frequent underlying conditions were hematological malignancy (40%) and solid organ transplantation (29%). Galactomannan was detected in the serum of 64% of patients. In 75% of cases, at least one of galactomannan, Aspergillus PCR, and ß-d-glucan was positive in the cerebrospinal fluid. Six-week mortality was 45%. Two distinct patterns of disease were identified according to presumed route of dissemination. Presumed haematogenous dissemination (n = 88) was associated with a higher frequency of impaired consciousness (64%), shorter time to diagnosis, the presence of multiple abscesses (70%), microangiopathy (52%), detection of serum galactomannan (69%) and Aspergillus PCR (68%), and higher six-week mortality (54%). By contrast, contiguous dissemination from the paranasal sinuses (n = 31) was associated with a higher frequency of cranial nerve palsy (65%), evidence of meningitis on cerebral imaging (83%), macrovascular lesions (61%), delayed diagnosis, and lower six-week mortality (30%). In multivariate analysis and in a risk prediction model, haematogenous dissemination, hematological malignancy and the detection of serum galactomannan were associated with higher six-week mortality. CONCLUSION: Distinguishing between hematogenous and contiguous dissemination patterns appears to be critical in the workup for CA, as they are associated with significant differences in clinical presentation and outcome.
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Antifúngicos , Aspergilosis , Antifúngicos/uso terapéutico , Aspergilosis/diagnóstico , Aspergillus , Estudios de Cohortes , Grano Comestible/química , Humanos , Mananos/análisisRESUMEN
The Quality Management System in medical mycology refers to the systematic monitoring with internal and external quality controls: it needs to be organized in the laboratory. ISO 15189 standard is not precise in how to demonstrate the correctness of tests, in terms of frequency and requirements for quality controls QC. That's why the COFRAC, the French Accreditation Committee has published guides to which we should refer. The laboratory has to apply internal Quality Control Programs. They consist of various tests to check the reagents including the culture media. Reference strains have to be provided and preparations of homemade reagents are needed, because few are commercialized. Maintaining the competence of the technical staff through identification of unknown strains is also required. In the fungal serology field, home made antibodies with pooled sera or antigen controls are needed. This monitoring has to follow the recommandations from the Cofrac technical guide LAB GTA 06. For quantitative analysis, the Levey-Jennings chart is a graph with quality control data plotted on to give a visual indication. Some external QC references, besides the national quality control AFSSAPS, are available. Data evaluation, corrective actions in case of out of range results and preventive actions have to be determined in the Quality System documents and presented in the annual management review.
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OBJECTIVES: Malaria is one of most common tropical diseases encountered in travellers and migrants. It requires an urgent and reliable diagnosis considering its potential severity. In this study, performance of five diagnostic assays were evaluated in a nonendemic region and compared prospectively to quantitative PCR (qPCR). METHODS: A prospective study was conducted at Toulouse Hospital from August 2017 to January 2018 and included all patients with initial Plasmodium screening. Thin and thick blood smears (TnS, TkS), quantitative buffy coat (QBC), rapid diagnostic tests (RDTs) and commercial loop-mediated isothermal amplification (LAMP) were independently performed on each blood sample and compared to our qPCR reference standard. RESULTS: The study encompassed 331 patients, mainly returning from Africa. qPCR detected 73 Plasmodium-positive samples (including 58 falciparum). Individually, LAMP had a 97.3% (71/73) sensitivity, far ahead of TnS (84.9%, 62/73), TkS (86.3%, 63/73), QBC (86.3%, 63/73) and RDT (86.3%, 63/73). RDT demonstrated a high sensitivity for falciparum (98.3%, 57/58) but missed all ovale, malariae and knowlesi infections. Specificity was excellent for all techniques (99.6-100%). The most sensitive diagnosis strategies were TnS + RDT (95.9%, 70/73), TnS + LAMP (97.3%, 71/73) and TnS + RDT + LAMP (100%, 73/73), about 10% higher than strategies using exclusively microscopy, TkS + TnS (87.7%, 64/73) or QBC + TnS (87.7%, 64/73). TnS remains necessary for Plasmodium species identification and quantification. Adding sequentially TnS only on LAMP-positive samples did not decrease TnS + LAMP strategy sensitivity. CONCLUSIONS: In nonendemic countries, the currently recommended microscopy-based strategies seem unsatisfactory for malaria diagnosis considering RDT and LAMP performance, two rapid and sensitive assays that require limited training.
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Enfermedades Transmisibles Importadas/diagnóstico , Malaria/diagnóstico , Microscopía/normas , Técnicas de Diagnóstico Molecular/normas , Técnicas de Amplificación de Ácido Nucleico/normas , África , Enfermedades Transmisibles Importadas/parasitología , Francia , Humanos , Malaria/parasitología , Microscopía/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Plasmodium , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Sensibilidad y Especificidad , TemperaturaRESUMEN
OBJECTIVES: To describe the epidemiological, clinical and microbiological characteristics and mortality of patients with Candida bloodstream infection and systemic autoimmune diseases. METHODS: We performed a retrospective multicenter study of candidemia in adults with systemic autoimmune diseases between 2010 and 2016. RESULTS: Among 1040 patients with candidemia, 36 (3.5%) had a systemic autoimmune disease. The most common systemic autoimmune disease was rheumatoid arthritis (27.8%). The most common species was Candida albicans (66.7%). Twenty-two (61.1%) patients received a corticosteroid therapy and nine (25%) received an immunosuppressive therapy at the time of candidemia. The mortality rate was 27.8%. CONCLUSIONS: Systemic autoimmune diseases are not common in patients with candidemia. The unadjusted mortality rate was comparable to other candidemia studies in the general population.
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Enfermedades Autoinmunes/complicaciones , Candidemia/etiología , Infecciones Oportunistas/etiología , Corticoesteroides/efectos adversos , Corticoesteroides/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Artritis Reumatoide/complicaciones , Artritis Reumatoide/inmunología , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/inmunología , Candida/clasificación , Candida/aislamiento & purificación , Candidemia/epidemiología , Candidemia/microbiología , Comorbilidad , Infección Hospitalaria/epidemiología , Infección Hospitalaria/etiología , Femenino , Francia/epidemiología , Humanos , Huésped Inmunocomprometido , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Masculino , Metotrexato/efectos adversos , Metotrexato/uso terapéutico , Persona de Mediana Edad , Infecciones Oportunistas/epidemiología , Estudios Retrospectivos , España/epidemiología , Tasa de SupervivenciaRESUMEN
A survey of mycology laboratories for antifungal susceptibility testing (AFST) was undertaken in France in 2018, to better understand the difference in practices between the participating centers and to identify the difficulties they may encounter as well as eventual gaps with published standards and guidelines. The survey captured information from 45 mycology laboratories in France on how they perform AFST (number of strains tested, preferred method, technical and quality aspects, interpretation of the MIC values, reading and interpretation difficulties). Results indicated that 86% of respondents used Etest as AFST method, with a combination of one to seven antifungal agents tested. Most of the participating laboratories used similar technical parameters to perform their AFST method and a large majority used, as recommended, internal and external quality assessments. Almost all the participating mycology laboratories (98%) reported difficulties to interpret the MIC values, especially when no clinical breakpoints are available. The survey highlighted that the current AFST practices in France need homogenization, particularly for MIC reading and interpretation.
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Antifúngicos/uso terapéutico , Laboratorios , Pruebas de Sensibilidad Microbiana , Micología , Práctica Profesional/estadística & datos numéricos , Pruebas Antimicrobianas de Difusión por Disco/métodos , Pruebas Antimicrobianas de Difusión por Disco/normas , Pruebas Antimicrobianas de Difusión por Disco/estadística & datos numéricos , Farmacorresistencia Fúngica , Francia , Historia del Siglo XXI , Humanos , Laboratorios/normas , Laboratorios/estadística & datos numéricos , Ensayos de Aptitud de Laboratorios/métodos , Ensayos de Aptitud de Laboratorios/estadística & datos numéricos , Pruebas de Sensibilidad Microbiana/métodos , Pruebas de Sensibilidad Microbiana/normas , Pruebas de Sensibilidad Microbiana/estadística & datos numéricos , Micología/historia , Micología/métodos , Micología/normas , Micología/estadística & datos numéricos , Práctica Profesional/normas , Control de Calidad , Encuestas y CuestionariosRESUMEN
The aim of this study was to determine the incidence of congenital toxoplasmosis (CT) and to assess the performances of prenatal and neonatal diagnoses. From 1994-2005, in Toulouse University Hospital, France, amniocentesis was performed on 352 pregnant women who were infected during pregnancy. All women were treated with spiramycin and pyrimethamine-sulfadoxine when prenatal diagnosis was positive. Among the 275 foetuses with follow-up, 66 (24%) were infected. The transmission rates of Toxoplasma gondii were 7%, 24% and 59% in the first, second and third trimesters, respectively. The sensitivity and specificity of PCR on amniotic fluid (AF) were 91% and 99.5%, respectively. One case was diagnosed by mouse inoculation with AF and six cases were diagnosed by neonatal or postnatal screening. The sensitivity and specificity of PCR on placentas were 52% and 99%, respectively. The sensitivity of tests for the detection of specific IgA and IgM in cord blood was 53% and 64%, respectively, and specificity values were 91% and 92%. In conclusion, PCR performed on AF had the highest levels of sensitivity and specificity for the diagnosis of CT. This permits an early diagnosis of most cases and should be recommended.
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Complicaciones Parasitarias del Embarazo/diagnóstico , Toxoplasma , Toxoplasmosis Congénita/diagnóstico , Amniocentesis , Animales , Anticuerpos Antiprotozoarios/sangre , ADN Protozoario/análisis , Combinación de Medicamentos , Ensayo de Inmunoadsorción Enzimática , Femenino , Francia/epidemiología , Hospitales Universitarios , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Incidencia , Recién Nacido , Reacción en Cadena de la Polimerasa , Valor Predictivo de las Pruebas , Embarazo , Complicaciones Parasitarias del Embarazo/epidemiología , Diagnóstico Prenatal , Pirimetamina/uso terapéutico , Sensibilidad y Especificidad , Espiramicina/uso terapéutico , Sulfadoxina/uso terapéutico , Toxoplasma/genética , Toxoplasma/inmunología , Toxoplasmosis Congénita/tratamiento farmacológico , Toxoplasmosis Congénita/epidemiologíaRESUMEN
OBJECTIVES: To determine the Etest-based epidemiological cut-off values (ECVs) for antifungal agents against the most frequent yeast and Aspergillus fumigatus species isolated in 12 French hospitals. METHODS: For each antifungal agent, the Etest MICs in yeast and A. fumigatus isolates from 12 French laboratories were retrospectively collected from 2004 to 2018. The ECVs were then calculated using the iterative statistical method with a 97.5% cut-off. RESULTS: Forty-eight Etest ECVs were determined for amphotericin B, caspofungin, micafungin, anidulafungin, fluconazole, voriconazole, posaconazole and itraconazole, after pooling and analysing the MICs of 9654 Candida albicans, 2939 Candida glabrata SC, 1458 Candida parapsilosis SC, 1148 Candida tropicalis, 575 Candida krusei, 518 Candida kefyr, 241 Candida lusitaniae, 131 Candida guilliermondii and 1526 Aspergillus fumigatus species complex isolates. These ECVs were 100% concordant (identical or within one two-fold dilution) with the previously reported Etest-based ECVs (when available), and they were concordant in 76.1% of cases with the Clinical and Laboratory Standards Institute ECVs and in 81.6% of cases with the European Committee on Antimicrobial Susceptibility Testing ECVs. CONCLUSIONS: On the basis of these and other previous results, we recommend the determination of method-dependent ECVs. Etest ECVs should not be used instead of breakpoints, but may be useful to identify non-wild-type isolates with potential resistance to antifungal agents, and to indicate that an isolate may not respond as expected to the standard treatment.
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Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Candida/efectos de los fármacos , Aspergillus fumigatus/aislamiento & purificación , Candida/aislamiento & purificación , Pruebas Antimicrobianas de Difusión por Disco , Farmacorresistencia Fúngica , Determinación de Punto Final , Francia/epidemiología , Humanos , Pruebas de Sensibilidad Microbiana/normas , Pruebas de Sensibilidad Microbiana/estadística & datos numéricos , Micosis/epidemiología , Micosis/microbiología , Estudios RetrospectivosRESUMEN
Rapid and precise diagnosis of malaria is needed to take care febrile patient returning from endemic areas. Since the first description of the diagnosis of Plasmodium infection by polymerase-chain-reaction (PCR), the role of this kind of molecular method in the laboratory diagnosis of imported malaria is still a topical question. PCR-based assays were found to be more sensitive and more specific than all conventional methods. The highest contribution of the molecular diagnosis is that a PCR negative result would ascertain the lack of any malaria infection, thus quickly orienting the investigations toward other aetiology. This technique should be now considered as the gold standard for the diagnosis of imported malaria.
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Malaria/diagnóstico , Plasmodium/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Animales , ADN Protozoario/química , ADN Protozoario/genética , Diagnóstico Diferencial , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Treatment of Scedosporium apiospermum mycetoma usually requires limb amputation. A 49-year-old woman, from Ivory Coast, was diagnosed with Madura foot in 1995. She failed to respond to several treatments including itraconazole, fluconazole and co-trimoxazole, and refused limb amputation. In December 2002 she was admitted to hospital in France with a painful, swollen right leg and foot. She had no fever and C-reactive protein was 120 mg/l. Magnetic resonance imaging (MRI) confirmed the destruction of tarsus bones with a tibia extension. Voriconazole (400 mg/day) treatment was initiated in March 2003; a significant clinical improvement was observed within 4 months as confirmed by C-reactive protein (16 mg/l) and MRI. Voriconazole was maintained for 18 months with good tolerance. Cholestasis appeared after the first month and remained stable. In October 2004 voriconazole was discontinued due to side effects on the liver (alanine aminotransferase 17 times the normal level); MRI showed impressive regression of bone lesions. As of July 2005, the patient remains clinically well. Voriconazole appears to be a promising drug for the treatment of S. apiospermum mycetomas.
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Antifúngicos/uso terapéutico , Enfermedades Óseas Infecciosas/tratamiento farmacológico , Micetoma/tratamiento farmacológico , Pirimidinas/uso terapéutico , Scedosporium , Triazoles/uso terapéutico , Enfermedades Óseas Infecciosas/microbiología , Enfermedades Óseas Infecciosas/patología , Femenino , Humanos , Persona de Mediana Edad , Micetoma/patología , Huesos Tarsianos/microbiología , Huesos Tarsianos/patología , Tibia/microbiología , Tibia/patología , Resultado del Tratamiento , VoriconazolRESUMEN
The main objective of this study was to assess the diagnostic performance of a set of three Mucorales quantitative PCR assays in a retrospective multicentre study. Mucormycosis cases were recorded thanks to the French prospective surveillance programme (RESSIF network). The day of sampling of the first histological or mycological positive specimen was defined as day 0 (D0). Detection of circulating DNA was performed on frozen serum samples collected from D-30 to D30, using quantitative PCR assays targeting Rhizomucor, Lichtheimia, Mucor/Rhizopus. Forty-four patients diagnosed with probable (n = 19) or proven (n = 25) mucormycosis were included. Thirty-six of the 44 patients (81%) had at least one PCR-positive serum. The first PCR-positive sample was observed 9 days (range 0-28 days) before diagnosis was made using mycological criteria and at least 2 days (range 0-24 days) before imaging. The identifications provided with the quantitative PCR assays were all concordant with culture and/or PCR-based identification of the causal species. Survival rate at D84 was significantly higher for patients with an initially positive PCR that became negative after treatment initiation than for patients whose PCR remained positive (48% and 4%, respectively; p <10-6). The median time for complete negativity of PCR was 7 days (range 3-19 days) after initiation of l-AmB treatment. Despite some limitations due to the retrospective design of the study, we showed that Mucorales quantitative PCR could not only confirm the mucormycosis diagnosis when other mycological arguments were present but could also anticipate this diagnosis. Quantification of DNA loads may also be a useful adjunct to treatment monitoring.
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ADN de Hongos , Mucorales/genética , Mucormicosis/diagnóstico , Mucormicosis/microbiología , Anciano , Anciano de 80 o más Años , Comorbilidad , ADN de Hongos/sangre , Femenino , Francia/epidemiología , Fungemia , Humanos , Masculino , Persona de Mediana Edad , Mucormicosis/epidemiología , Mucormicosis/terapia , Vigilancia de la Población , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
Since the first description, in 1990, of the diagnosis of Plasmodium falciparum infection by polymerase-chain-reaction (PCR), the role of this kind of molecular method in laboratory diagnosis of imported malaria is still a topical question. Various molecular assays have been used, the first of which was hybridization using labeled probes in 1984. When compared to thick blood smear, this test displayed a sensitivity ranging from 65% to 81% and specificity was close to 100%. The next technical improvement was the introduction of the so-called polymerase chain reaction (PCR), the principle of which was described in 1985. In 1993, a PCR-based assay detecting all four Plasmodium species was published, followed by different variants of this method. By the turn of the century, novel real-time PCR slashed workaround time, which dropped from 2 1/2 hours to less than 1 hour. Moreover, automatic reading with no human action on PCR products reduced the risks of contamination. The first application of real-time PCR to the diagnosis of malaria was published in 2001. PCR-based assays were found to be more sensitive than all conventional methods. Variations in sensitivity were probably due to different medical practices as well as to the proportion of various types of subjects (travelers under chemoprophylaxis, immigrants from malaria-endemic areas) in the population undergoing malaria diagnosis. The target of the primers was also of crucial importance: for the detection of P. falciparum, the most efficient assays amplified either the gene SSUrRNA, or Pf155/RESA, or Cox 1. Specificity of PCR results is guaranteed by the nature of the target for primers or probes, as determined by the studies of the Plasmodium genome whose results are available in GenBank. PCR use often corrected the results of Plasmodium species identification by microscopy and PCR-based methods were found to be the most efficient for the detection of mixed infections. Concerning the diagnosis of imported malaria, it appears clearly that PCR should be considered as second-line method which can be especially interesting, as a negative result rules out malaria in febrile patients. However, the use of PCR assays appears to be restricted to health centers, such as University Hospitals, for whom malaria identification is an important and routine problem. In the future, the detection of mutations related to drug resistance could be used to orient anti-malarial therapy.
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ADN Bacteriano/análisis , Malaria Falciparum/diagnóstico , Malaria Falciparum/genética , Reacción en Cadena de la Polimerasa , Automatización , Diagnóstico Diferencial , Humanos , Manejo de EspecímenesAsunto(s)
Coccidioidomicosis/transmisión , Trasplante de Pulmón/efectos adversos , Receptores de Trasplantes , Coccidioidomicosis/diagnóstico , Coccidioidomicosis/patología , Resultado Fatal , Francia , Humanos , Trasplante de Pulmón/métodos , Masculino , Persona de Mediana Edad , Perú , Radiografía Torácica , Donantes de Tejidos , Enfermedad Relacionada con los ViajesRESUMEN
Phospholipases A(2) (PLA(2)) play an important role in Toxoplasma gondii host cell penetration. They are also key enzymes in the host cell response to the parasite invasion. PLA(2) hydrolyse cellular phospholipids, releasing multiple inflammatory lipidic mediators. We have investigated the biochemical characterisation of T. gondii PLA(2) activity in a mouse-cultured tachyzoite homogenate and in the peritoneal exudate from infected mice, using the hydrolysis of a fluorescent phosphatidylglycerol labelled at the sn-2 position. Spectrofluorimetry and thin-layer chromatography showed a PLA(2) activity (about 0.5-2 nmol/min per mg), calcium-independent, secreted into infected mice peritoneal exudate, with a broad pH activity ranging between 6.5 and 9.5 and resistant to a great number of potential PLA(2) inhibitors except dithio-nitrobenzoic acid (1 mM). An associated phospholipase A(1) activity was also displayed. These results suggest that Toxoplasma gondii displays specific phospholipases different from host enzymes and probably involved at critical steps of infectious cycle.