Deciphering Unexpected Vascular Locations of Scedosporium spp. and Lomentospora prolificans Fungal Infections, France.

Scedosporium spp. and Lomentospora prolificans are emerging non-Aspergillus filamentous fungi. The Scedosporiosis/lomentosporiosis Observational Study we previously conducted reported frequent fungal vascular involvement, including aortitis and peripheral arteritis. For this article, we reviewed 7 cases of Scedosporium spp. and L. prolificans arteritis from the Scedosporiosis/lomentosporiosis Observational Study and 13 cases from published literature. Underlying immunosuppression was reported in 70% (14/20) of case-patients, mainly those who had solid organ transplants (10/14). Osteoarticular localization of infection was observed in 50% (10/20) of cases; infections were frequently (7/10) contiguous with vascular infection sites. Scedosporium spp./Lomentospora prolificans infections were diagnosed in 9 of 20 patients ≈3 months after completing treatment for nonvascular scedosporiosis/lomentosporiosis. Aneurysms were found in 8/11 aortitis and 6/10 peripheral arteritis cases. Invasive fungal disease--related deaths were high (12/18 [67%]). The vascular tropism of Scedosporium spp. and L. prolificans indicates vascular imaging, such as computed tomography angiography, is needed to manage infections, especially for osteoarticular locations.

Invasive Aspergillosis Due to Aspergillus Section Usti: A Multicenter Retrospective Study.

BACKGROUND: Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergillosis (IA). This multicenter study describes the epidemiology and outcome of A. ustus infections. METHODS: Patients with A. ustus isolated from any clinical specimen were retrospectively identified in 22 hospitals from 8 countries. When available, isolates were sent for species identification (BenA/CaM sequencing) and antifungal susceptibility testing. Additional cases were identified by review of the literature. Cases were classified as proven/probable IA or no infection, according to standard international criteria. RESULTS: Clinical report forms were obtained for 90 patients, of whom 27 had proven/probable IA. An additional 45 cases were identified from literature review for a total of 72 cases of proven/probable IA. Hematopoietic cell and solid-organ transplant recipients accounted for 47% and 33% cases, respectively. Only 8% patients were neutropenic at time of diagnosis. Ongoing antimold prophylaxis was present in 47% of cases. Pulmonary IA represented 67% of cases. Primary or secondary extrapulmonary sites of infection were observed in 46% of cases, with skin being affected in 28% of cases. Multiple antifungal drugs were used (consecutively or in combination) in 67% of cases. The 24-week mortality rate was 58%. A. calidoustus was the most frequent causal agent. Minimal inhibitory concentrations encompassing 90% isolates (MIC90) were 1, 8, >16, and 4 µg/mL for amphotericin B, voriconazole, posaconazole, and isavuconazole, respectively. CONCLUSIONS: Aspergillus ustus IA mainly occurred in nonneutropenic transplant patients and was frequently associated with extrapulmonary sites of infection. Mortality rate was high and optimal antifungal therapy remains to be defined.

Antifungal Susceptibility of 182 Fusarium Species Isolates from 20 European Centers: Comparison between EUCAST and Gradient Concentration Strip Methods.

We determined the susceptibility of 182 Fusarium species isolates to five antifungal drugs (amphotericin B, voriconazole, posaconazole, isavuconazole, and terbinafine) by the EUCAST method. Based on the latest taxonomic insights, isolates collected from 20 European centers were distributed into seven complexes and 27 species. The susceptibility was variable, depending on the species. Comparison with the gradient concentration strip method, which was used for 77 isolates, showed essential agreement values for voriconazole, posaconazole, isavuconazole, and amphotericin B of 17%, 91%, 83%, and 70%, respectively.

Weekly high-dose liposomal amphotericin B prevents invasive aspergillosis after heart transplantation.

BACKGROUND: Preventive strategies for invasive aspergillosis (IA) have still not been determined in heart transplant recipients whereas IA leads to a high mortality rate at 12 months posttransplantation. The use of voriconazole or echinocandins was proposed but can favor emergence of Aspergillus or Candida sp. resistant strains or promote neurological and liver disorders in some patients. OBJECTIVES: To assess whether universal prophylaxis with weekly high-dose of liposomal amphotericin-B (L-AmB) can safely prevent IA in heart transplant recipients. PATIENTS/METHODS: Retrospective before/after study that included 142 patients who received heart transplantation between 2010 and 2019 at the University Hospital of Toulouse (France). Weekly high dose of L-AmB (7.5 mg/kg/week) was used as universal prophylaxis from 2016 because of high environmental exposure to Aspergillus sp. and high incidence of IA. RESULTS: Cumulative 1-year incidence of IA decreased from 23% to 5% after introduction of L-Amb prophylaxis. Multivariate analysis (Cox model) identified L-AmB prophylaxis as a protective factor against IA (hazard ratio [HR] 0.21 [95% confidence interval 0; 0.92], p = .04), whereas postoperative renal replacement therapy was associated with IA (HR 3.6 [95% confidence interval 1.38; 9.3], p = .001), after correction for confounding effects (induction regimen, methylprednisolone pulses and history of hematological malignancy). The incidence of acute kidney injury requiring renal replacement therapy was similar in the two groups, suggesting a low risk of kidney toxicity when L-AmB is used weekly. No patient developed severe kidney electrolyte loss nor L-AmB-related anaphylaxis. CONCLUSIONS: Once-weekly high-dose L-AmB is safe and may prevent the development of IA after heart transplantation.

Invasive aspergillosis due to Aspergillus cryptic species: A prospective multicentre study.

OBJECTIVES: Aspergillus cryptic species are increasingly recognised causes of Aspergillus diseases, including life-threatening invasive aspergillosis (IA). However, as their accurate identification remains challenging in a routine practice, few is known from a clinical and epidemiological perspective. Recently, the MSI application has emerged as a powerful tool for the detection and identification of Aspergillus cryptic species. We aimed to use to the network of users of the MSI application to conduct a multicentre prospective screening of Aspergillus cryptic species-related IA and analyse their epidemiological, clinical and mycological characteristics. METHODS: Over a 27-month period, the clinical involvement of 369 Aspergillus cryptic isolates, from 13 French and Danish MSI application users, was prospectively analysed. Species identification was confirmed by DNA-sequencing and antifungal susceptibility testing was performed using EUCAST reference method. Fifty-one A fumigatus sensu stricto invasive cases were also analysed. RESULTS: Fifteen cryptic isolates were responsible of IA. Eight species were involved, including 5 cases related to the species A sublatus. These species showed high rate of in vitro low susceptibility to antifungal drugs. In comparison with A fumigatus sensu stricto invasive cases, pre-exposure to azole drugs was significantly associated with cryptic IA (P = .02). DISCUSSION: This study brings new insights in cryptic species related IA and underlines the importance to identify accurately at the species level these Aspergillus isolates. The increasing use of antifungal drugs might lead in the future to an epidemiologic shift with an emergence of resistant isolates involved in IA.

Outcomes of solid organ transplant recipients with invasive aspergillosis and other mold infections.

OBJECTIVES: To characterize the clinical presentation and outcomes of invasive mold infections (IMI) in solid organ transplant (SOT) recipients. METHODS: Inclusion of all SOT recipients with IMI diagnosed between 2008 and 2016 at a referral center for SOT. Univariable analyses identified factors associated with death at one year, and logistic regression models retained independent predictors. RESULTS: Of the 1739 patients that received a SOT during this period, 68 developed IMI (invasive aspergillosis [IA] in 58). Cumulative incidence of IMI at 1 year ranged from 1.2% to 18.8% (kidney and heart transplantation, respectively). At baseline, compared with other IMI, the need for vasoactive drugs was more frequent in patients with IA. During follow-up, 35 patients (51%) were admitted to the ICU and required mechanical ventilation (n = 27), vasoactive drugs (n = 31), or renal replacement therapy (n = 31). The need for vasoactive drugs (OR 7.34; P = .003) and a positive direct examination (OR 10.1; P = .004) were independently associated with the risk of death at 1 year in patients with IA (n = 33; 57%) CONCLUSIONS: Characteristics of IMI at presentation varied according to the underlying transplanted organ and the mold species. Following IA, one-year mortality may be predicted by the need for hemodynamic support and initial fungal load.

Multi-centric evaluation of the online MSI platform for the identification of cryptic and rare species of Aspergillus by MALDI-TOF.

The taxonomy of Aspergillus species has recently been revolutionized with the introduction of cryptic species and section concepts. However, their species-level identification in routine laboratories remains a challenge. The aim of this study was to prospectively assess the identification accuracy of cryptic species of Aspergillus in various laboratories using the mass spectrometry identification (MSI) platform, an independent and freely accessible online mass spectrometry database. Over a 12-month period, when a select set of MSI users identified cryptic species, they were contacted and requested to send the isolates to our laboratory for sequence-based identification. Sequence and MSI identification results were then compared. During the study period, 5108 Aspergillus isolates were identified using MSI including 1477 (28.9%) cryptic species. A total of 245 isolates that corresponded to 56 cryptic species and 13 sections were randomly selected for DNA sequencing confirmation. Agreement between the two methods was 99.6% at the section level and 66.1% at the species level. However, almost all discrepancies (72/83, 86.7%) were misidentifications between closely related cryptic species belonging to the same section. Fifty-one isolates from noncryptic species were also identified, thus yielding 100% and 92.2% agreement at the section and species level, respectively. Although the MSI fungus database is a reliable tool to identify Aspergillus at the section level, the database still requires adjustment to correctly identify rare or cryptic species at the species level. Nevertheless, the application properly differentiated between cryptic and sensu stricto species in the same section, thus alerting on possible specific isolate characteristics.

Early necrotic skin lesions after a ABO-incompatible kidney transplantation: The threat of Cunninghamella Spp.

A 49-year-old man underwent ABO-incompatible kidney transplantation with a living donor. At day 33 post-transplantation, he presented with undiagnosed epilepsy with generalized tonic-clonic seizures. At day 44 post-transplantation, he developed left-sided pneumonia attributed to Aspergillus fumigatus and treatment with liposomal amphotericin B was initiated. At day 51 post-transplantation, necrotic skin lesions appeared. DNA sequencing in a fresh cutaneous biopsy finally identified Cunninghamella Spp., a member of the order Mucorales. Unfortunately, the necrotic lesions spread, and the patient died at day 60 post-transplantation. This case report highlights the infectious risk related to ABO-incompatible kidney transplantation and suggests a requirement for rapid identification of every skin lesion, even in the early phases of immunosuppression.

Quantitative PCR (qPCR) Detection of Mucorales DNA in Bronchoalveolar Lavage Fluid To Diagnose Pulmonary Mucormycosis.

Early diagnosis and treatment are essential to improving the outcome of mucormycosis. The aim of this retrospective study was to assess the contribution of quantitative PCR detection of Mucorales DNA in bronchoalveolar lavage fluids for early diagnosis of pulmonary mucormycosis. Bronchoalveolar lavage fluid samples (n = 450) from 374 patients with pneumonia and immunosuppressive conditions were analyzed using a combination of 3 quantitative PCR assays targeting the main genera involved in mucormycosis in France (Rhizomucor, Mucor/Rhizopus, and Lichtheimia). Among these 374 patients, 24 patients had at least one bronchoalveolar lavage fluid sample with a positive PCR; 23/24 patients had radiological criteria for invasive fungal infections according to consensual criteria; 10 patients had probable or proven mucormycosis, and 13 additional patients had other invasive fungal infections (4 probable aspergillosis, 1 proven fusariosis, and 8 possible invasive fungal infections). Only 2/24 patients with a positive PCR result on a bronchoalveolar lavage fluid sample had a positive Mucorales culture. PCR was also positive on serum in 17/24 patients. In most cases, a positive PCR result was first detected using sera (15/17). However, a positive PCR on bronchoalveolar lavage fluid was the earliest and/or the only biological test revealing mucormycosis in 4 patients with a final diagnosis of probable or proven mucormycosis, 3 patients with probable aspergillosis, and one patient with a possible invasive fungal infection. Mucorales PCR performed on bronchoalveolar lavage fluid could provide additional support for earlier administration of Mucorales-directed antifungal therapy, thus improving the outcome of lung mucormycosis cases.

Molecular diagnosis of toxoplasmosis in immunocompromised patients: a 3-year multicenter retrospective study.

Toxoplasmosis is a life-threatening infection in immunocompromised patients (ICPs). The definitive diagnosis relies on parasite DNA detection, but little is known about the incidence and burden of disease in HIV-negative patients. A 3-year retrospective study was conducted in 15 reference laboratories from the network of the French National Reference Center for Toxoplasmosis, in order to record the frequency of Toxoplasma gondii DNA detection in ICPs and to review the molecular methods used for diagnosis and the prevention measures implemented in transplant patients. During the study period, of 31,640 PCRs performed on samples from ICPs, 610 were positive (323 patients). Blood (n = 337 samples), cerebrospinal fluid (n = 101 samples), and aqueous humor (n = 100 samples) were more frequently positive. Chemoprophylaxis schemes in transplant patients differed between centers. PCR follow-up of allogeneic hematopoietic stem cell transplant (allo-HSCT) patients was implemented in 8/15 centers. Data from 180 patients (13 centers) were further analyzed regarding clinical setting and outcome. Only 68/180 (38%) patients were HIV(+); the remaining 62% consisted of 72 HSCT, 14 solid organ transplant, and 26 miscellaneous immunodeficiency patients. Cerebral toxoplasmosis and disseminated toxoplasmosis were most frequently observed in HIV and transplant patients, respectively. Of 72 allo-HSCT patients with a positive PCR result, 23 were asymptomatic; all were diagnosed in centers performing systematic blood PCR follow-up, and they received specific treatment. Overall survival of allo-HSCT patients at 2 months was better in centers with PCR follow-up than in other centers (P < 0.01). This study provides updated data on the frequency of toxoplasmosis in HIV-negative ICPs and suggests that regular PCR follow-up of allo-HSCT patients could guide preemptive treatment and improve outcome.

Multicentric comparative assessment of the bio-evolution Toxoplasma gondii detection kit with eight laboratory-developed PCR assays for molecular diagnosis of congenital toxoplasmosis.

The detection of Toxoplasma gondii in amniotic fluid is an essential tool for the prenatal diagnosis of congenital toxoplasmosis and is currently essentially based on the use of PCR. Although some consensus is emerging, this molecular diagnosis suffers from a lack of standardization and an extreme diversity of laboratory-developed methods. Commercial kits for the detection of T. gondii by PCR were recently developed and offer certain advantages; however, they must be assessed in comparison with optimized reference PCR assays. The present multicentric study aimed to compare the performances of the Bio-Evolution T. gondii detection kit and laboratory-developed PCR assays set up in eight proficient centers in France. The study compared 157 amniotic fluid samples and found concordances of 99% and 100% using 76 T. gondii-infected samples and 81 uninfected samples, respectively. Moreover, taking into account the classification of the European Research Network on Congenital Toxoplasmosis, the overall diagnostic sensitivity of all assays was identical and calculated to be 86% (54/63); specificity was 100% for all assays. Finally, the relative quantification results were in good agreement between the kit and the laboratory-developed assays. The good performances of this commercial kit are probably in part linked to the use of a number of good practices: detection in multiplicate, amplification of the repetitive DNA target rep529, and the use of an internal control for the detection of PCR inhibitors. The only drawbacks noted at the time of the study were the absence of uracil-N-glycosylase and small defects in the reliability of the production of different reagents.

Characterization and multicentric validation of a common standard for Toxoplasma gondii detection using nucleic acid amplification assays.

The molecular diagnosis of toxoplasmosis essentially relies upon laboratory-developed methods and suffers from lack of standardization, hence the large diversity of performances between laboratories. Moreover, quantifications of parasitic loads differ among centers, a fact which prevents the possible prediction of the severity of this disease as a function of parasitic loads. The objectives of this multicentric study performed in eight proficient laboratories of the Molecular Biology Pole of the French National Reference Center for Toxoplasmosis (NRC-T) were (i) to assess the suitability of a lyophilized preparation of Toxoplasma gondii as a common standard for use in this PCR-based molecular diagnosis and (ii) to make this standard available to the community. High-quality written procedures were used for the production and qualification of this standard. Three independent batches of this standard, containing concentrations ranging from 10(4) to 0.01 T. gondii genome equivalents per PCR, were first assessed: the linear dynamic range was ≥ 6 log, the intra-assay coefficients of variation (CV) from a sample containing 10 T. gondii organisms per PCR were 0.3% to 0.42%, and the interassay CV over a 2-week period was 0.76% to 1.47%. A further assessment in eight diagnostic centers showed that the standard is stable, robust, and reliable. These lyophilized standards can easily be produced at a larger scale when needed and can be made widely available at the national level. To our knowledge, this is the first quality control assessment of a common standard which is usable both for self-evaluation in laboratories and for accurate quantification of parasitic loads in T. gondii prenatal infections.

A complementary tool for management of disseminated Histoplasma capsulatum var. capsulatum infections in AIDS patients.

In South America, disseminated histoplasmosis due to Histoplasma capsulatum var. capsulatum (H. capsulatum), is a severe and frequent opportunistic infection in AIDS patients. In areas outside the USA where specific-Histoplasma antigen detection is not available, the diagnosis is difficult. With the galactomannan antigen (GM) detection, a test commonly used for invasive aspergillosis diagnosis, there is a cross-reactivity with H. capsulatum that can be helpful for the diagnosis of histoplasmosis. The aim of this study was to evaluate the GM detection for the diagnosis of disseminated histoplasmosis in AIDS patients. The performance of the GM detection was evaluated with serum collected in French Guiana where H. capsulatum is highly endemic. Sera from AIDS patients with disseminated histoplasmosis occurring from 2002 to 2009 and from control HIV-positive patients without histoplasmosis were tested with the GM detection and Histoplasma-specific antibody detection (IEP). In 39 AIDS patients with proven disseminated histoplasmosis, the sensitivity of the Histoplasma IEP was only 35.9% and was linked to the TCD4+ lymphocyte level. For the GM detection, the sensitivity (Se) was 76.9% and specificity (Sp) was 100% with the recommended threshold for aspergillosis diagnosis (0.5). The test was more efficient with a threshold of 0.4 (Se: 0.82 [95% CI: 0.66-0.92], Sp: 1.00 [95% CI: 0.86-1.00], LR+: >10, LR-: 0.18). This study confirms that the GM detection can be a surrogate marker for the diagnosis of disseminated histoplasmosis in AIDS patients in endemic areas where Histoplasma EIA is not available.

No evidence of pathogenicity of Dientamoeba fragilis following detection in stools: A case-control study.

Dientamoeba fragilis is a ubiquitous intestinal parasite with detection in the stools that has become increasingly frequent following the advent of PCR as a routine screening tool. However, the pathogenicity of this parasite is still much debated. In order to assess the potentially pathogenic nature of this protozoan, a retrospective case-control study was carried out between January and December 2020 on patients from Toulouse University Hospital, with the aim of evaluating the potential clinical effects and changes in laboratory parameters linked to the presence and load of D. fragilis in stools. After matching age, sex and mode of care (consultation or hospitalisation), no significant difference was observed in the frequency of clinical signs between the 36 patients who tested positive for Dientamoeba fragilis PCR in their stools and the 72 control patients who were PCR negative for this protozoan. The presence of D. fragilis in the faeces was not associated with changes in laboratory parameters. Furthermore, a high digestive load of D. fragilis had no identifiable impact on clinical and laboratory parameters. Only the concomitant presence of Blastocystis sp. in stools was significantly more frequent in the D. fragilis group (uni- and multivariate analysis). Finally, this study showed no significant difference in clinical or laboratory signs between patients carrying Dientamoeba fragilis and the control group, regardless of the intestinal parasite load, suggesting that D. fragilis could be considered a commensal of the digestive tract.

Title: Aucune preuve de la pathogénicité de Dientamoeba fragilis détecté dans les selles : une étude cas-témoins. Abstract: Dientamoeba fragilis est un parasite digestif ubiquitaire dont la détection dans les selles est devenue de plus en plus fréquente avec l'avènement de la PCR comme outil de détection de routine. Cependant, la pathogénicité de ce parasite est encore très discutée. Afin d'évaluer le caractère potentiellement pathogène de ce protozoaire, une étude rétrospective cas-témoins a été réalisée entre janvier et décembre 2020 sur des patients du CHU de Toulouse, dans le but d'évaluer les effets cliniques et biologiques potentiels associés à la présence et à la charge de D. fragilis dans les selles. Après appariement sur l'âge, le sexe et le mode de prise en charge (consultation ou hospitalisation), aucune différence significative n'a été observée dans la fréquence des signes cliniques entre les 36 patients testés positifs pour la PCR de Dientamoeba fragilis dans les selles et les 72 patients témoins avec une PCR négative pour ce protozoaire. La présence de D. fragilis dans les selles n'était pas associée à des modifications des paramètres biologiques. De plus, une charge digestive élevée de D. fragilis n'avait pas d'impact identifiable sur les paramètres cliniques et biologiques. Seule la présence concomitante de Blastocystis sp. dans les selles était significativement plus fréquente dans le groupe D. fragilis (analyse uni- et multivariée). En conclusion, cette étude n'a pas montré de différence significative concernant les signes cliniques ou biologiques entre les patients porteurs de Dientamoeba fragilis et le groupe témoin, quelle que soit la charge parasitaire digestive, indiquant que D. fragilis pourrait être considéré comme un commensal du tube digestif.

Features of cryptococcosis among 652 HIV-seronegative individuals in France: a cross-sectional observational study (2005-2020).

OBJECTIVES: We aimed to describe features and outcomes of cryptococcosis among HIV-seronegative individuals in a large surveillance network for cryptococcosis in France. METHODS: We included incident cases of cryptococcosis in HIV-seronegative individuals from 2005 to 2020. We compared patient characteristics, disease presentations, cryptococcal antigen results, and induction antifungal treatments according to underlying disease. We examined factors associated with 90-day mortality. Among patients with disseminated infections, we investigated whether receipt of flucytosine and polyene combination was associated with lower mortality. RESULTS: Among 652 individuals, 209 (32.1%) had malignancy, 130 (19.9%) were solid-organ transplant recipients, 204 (31.3%) had other immunocompromising conditions, and 109 (16.7%) had no reported underlying factor. The commonest presentations were disseminated infections (63.3%, 413/652) and isolated pulmonary infections (25.3%, 165/652). Solid-organ transplant patients were most likely to have disseminated infections and a positive serum cryptococcal antigen result. Patients with malignancy were older and less likely to receive a flucytosine-containing regimen for disseminated infections than others (58.7%, 78/133 vs. 73.2%, 194/265; p 0.029). The crude 90-day case-fatality ratio was 27.2% (95% CI, 23.5%-31.1%). Age ≥60 years (aOR: 2.75 [1.78-4.26]; p < 0.001), meningitis/fungaemia (aOR: 4.79 [1.80-12.7]; p 0.002), and malignancy (aOR: 2.4 [1.14-5.07]; p 0.02) were associated with higher 90-day mortality. Receipt of flucytosine and polyene combination was associated with lower 90-day mortality (aOR: 0.40 [0.23-0.71]; p 0.002) in multivariable analysis and inverse probability of treatment weighted analysis (aOR: 0.45 [0.25-0.80]; p 0.006). DISCUSSION: HIV-seronegative individuals with cryptococcosis comprise a wide range of underlying conditions with different presentations and outcomes, requiring a tailored approach to diagnosis and management.

Cryptococcus neoformans Infections Differ Among Human Immunodeficiency Virus (HIV)-Seropositive and HIV-Seronegative Individuals: Results From a Nationwide Surveillance Program in France.

Among 1107 cryptococcosis cases from the French surveillance network (2005-2020), the proportion of HIV-seronegative individuals has recently surpassed that of HIV-seropositive individuals. We observed marked differences in patient characteristics, disease presentations, cryptococcal antigen results, infecting species, and mortality according to HIV serostatus.

An extraction method of positive blood cultures for direct identification of Candida species by Vitek MS matrix-assisted laser desorption ionization time of flight mass spectrometry.

Candida spp. are an important cause of nosocomial bloodstream infections. Currently, complete identification of yeasts with conventional methods takes several days. We report here the first evaluation of an extraction method associated with the Vitek MS matrix-assisted laser desorption ionization time of flight mass spectrometry for direct identification of Candida species from positive blood cultures. We evaluated this protocol with blood cultures that were inoculated with reference and routine isolates (eight reference strains, 30 patients isolates and six mixed cultures containing two strains of different Candida species), or from patients with candidemia (28 isolates). This method performed extremely well (97% correct identification) with blood cultures of single Candida spp. and significantly reduced the time of diagnosis. Nevertheless, subculture remains indispensable to test fungal resistance and to detect mixed infections.

Epidemiological, Clinical and Laboratory Features of Strongyloidiasis in 69 Attendees at a French Outpatient Clinic.

The present retrospective study analyzed the characteristics of strongyloidiasis in patients who were diagnosed at the Outpatient Clinic of the Department of Parasitology-Mycology, Toulouse, France. Sixty-nine file records were included in the study on the basis of a positive stool examination that used Baermann's method. The prominent epidemiological findings were the presence of former immigrants from Italy or Portugal, veterans from the 1st Indochina war, and autochthonous cases. Almost 1/4 of the patients were asymptomatic. Manifestations of skin allergy were the main clinical feature. Blood eosinophilia was present in 76.8% of the patients, and serum total IgE was ≥150 kIU/L in 79.7%. Immunodiagnosis was achieved from 1990 to 2001 by indirect immunofluorescence (IFAT) that was then replaced with ELISA, both methods using Strongyloides ratti filariform larvae. ELISA was found to be similar to IFAT in terms of specificity but exhibited a greater sensitivity. Patients were primarily treated with albendazole or ivermectin beginning in 1993. Forty-eight patients attended the follow-up consultation. Kinetics of the clinical picture and blood eosinophilia were found to be the most convenient parameters to assess the efficacy of anthelmintic therapy. In conclusion, strongyloidiasis remains a neglected disease in Southwestern France. The resolution of clinical features along with the kinetics of eosinophilia appeared to be the most appropriate parameters to check during the posttreatment follow-up.

Evaluation of the Performance of the Novodiag® Stool Parasites Assay for the Detection of Intestinal Protozoa and Microsporidia.

OBJECTIVES: We aimed to assess the performance of the Novodiag® Stool Parasites (NSP) assay in the diagnosis of the most common intestinal protozoan and microsporidia infections. METHODS: A panel of 167 selected stool samples was retrospectively analysed with the NSP assay and compared to routine microscopy and qPCR methods for the detection of pathogenic protozoa and microsporidia. RESULTS: Whereas specificity was high for all protozoa and microsporidia, NSP sensitivity was strongly dependent on the comparative method used as reference. When compared to microscopic methods, NSP sensitivity was high (96.7 to 100%) for Blastocystis hominis, Entamoeba histolytica and Cyclospora cayetanensis but was lower for Giardia intestinalis (85.2%) and ≤50% for Cystoisospora belli and Dientamoeba fragilis. In comparison to conventional qPCR, the NSP assay demonstrated lower sensitivity characteristics dependent on parasite loads, reaching 60 to 70% for G. intestinalis, D. fragilis, Cryptosporidium spp. and E. histolytica. Sensitivity was 100% for Enterocytozoon bieneusi, but none of the five samples containing Encephalitozoon spp. were detected. CONCLUSIONS: The overall performance of the NSP assay in the diagnosis of gastrointestinal protozoa and microsporidia seems to be better than or equivalent to that observed with microscopic methods but inferior to that obtainable with classical targeted qPCR.

Acquired fluconazole resistance and genetic clustering in Diutina (Candida) catenulata from clinical samples.

OBJECTIVES: Diutina (Candida) catenulata is an ascomycetous yeast isolated from environmental sources and animals, occasionally infecting humans. The aim of this study is to shed light on the in vitro antifungal susceptibility and genetic diversity of this opportunistic yeast. METHODS: Forty-five D. catenulata strains isolated from various sources (including human and environmental sources) and originating from nine countries were included. Species identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and confirmed via internal transcribed spacer ribosomal DNA barcoding. In vitro antifungal susceptibility was determined for seven systemic antifungals via the gradient strip method after 48 hours of incubation at 35°C using Etest® (Biomérieux) or Liofilchem® strips. Isolates exhibiting fluconazole minimal inhibitory concentrations (MICs) of ≥8 µg/mL were investigated for mutations in the ERG11 gene. A novel microsatellite genotyping scheme consisting of four markers was developed to assess genetic diversity. RESULTS: MIC ranges for amphotericin B, caspofungin, micafungin, isavuconazole, and posaconazole were 0.19-1 µg/mL, 0.094-0.5 µg/mL, 0.012-0.064 µg/mL, 0.003-0.047 µg/mL, and 0.006-0.032 µg/mL, respectively. By comparison, a broad range of MICs was noted for fluconazole (0.75 to >256 µg/mL) and voriconazole (0.012-0.38 mg/L), the higher values being observed among clinical strains. The Y132F amino acid substitution, associated with azole resistance in various Candida species (C. albicans, C. tropicalis, C. parapsilosis, and C. orthopsilosis), was the main substitution identified. Although microsatellite typing showed extensive genetic diversity, most strains with high fluconazole MICs clustered together, suggesting human-to-human transmission or a common source of contamination. DISCUSSION: The high rate of acquired fluconazole resistance among clinical isolates of D. catenulata is of concern. In this study, we highlight a link between the genetic diversity of D. catenulata and its antifungal resistance patterns, suggesting possible clonal transmission of resistant isolates.