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Introduction. Signal transducer and activator of transcription 3 (STAT3) deficiency is a rare primary immunodeficiency associated with increased susceptibility to bacterial and fungal infections, notably pulmonary aspergillosis. Aim. We describe the emergence of azole-resistant Aspergillus fumigatus infections in STAT3-deficient patients. Methodology. During a retrospective study of 13 pulmonary aspergillosis cases in STAT3-deficient patients conducted in France, we identified patients infected with azole-resistant A. fumigatus isolates. Results. Two out of the 13 STAT3-deficient patients with aspergillosis had azole-resistant A. fumigatus infection, indicating an unexpectedly high prevalence of resistance. The first patient with STAT3 deficiency presented several flares of allergic bronchopulmonary aspergillosis-like episodes. He was chronically infected with two azole-resistant A. fumigatus isolates (TR34/L98). Despite prolonged antifungal treatment, including caspofungin and amphotericin B, the patient was not able to clear the azole-resistant A. fumigatus. The second patient had chronic cavitary pulmonary aspergillosis (CCPA). The A. fumigatus isolate was initially azole susceptible but harboured three F46Y, M172V and E427K point mutations. Despite prolonged antifungal therapies, lesions worsened and the isolate became resistant to all azoles. Surgery and caspofungin treatments were then required to cure CCPA. Resistance was probably acquired from the environment (TR34/L98) in the first case whereas resistance developed under antifungal treatments in the second case. These infections required long-term antifungal treatments and surgery. Conclusions. The emergence of azole-resistant A. fumigatus infections in STAT3-deficiency dramatically impacts both curative and prophylactic antifungal strategies. Physicians following patients with primary immune-deficiencies should be aware of this emerging problem as it complicates management of the patient.

International audience; Oral candidiasis as a highly prevalent and recurrent infection in medically compromised individuals is mainly caused by the opportunistic fungal pathogen Candida albicans. This epithelial infection, if not controlled effectively, can progress to life-threatening systemic conditions and complications. The efficacy of current frontline antifungals is limited due to their poor bioavailability and systemic toxicity. As such, an efficient intervention is essential for controlling disease progression and recurrence. Herein, a theranostic nanoplatform (CD-Gu+-AmB) was developed to track the penetration of antifungals and perturb the invasion of C. albicans at oral epithelial tissues, via decorating the homemade red-emissive carbon dots (CD) with positively charged guanidine groups (Gu+) followed by conjugation with antifungal polyene (amphotericin B, AmB) in a reacting site-controllable manner. The generated CD-Gu+-AmB favorably gathered within the Candida cells and exhibited potent antifungal effects in both planktonic and biofilm forms. It selectively accumulated in the nuclei of human oral keratinocytes and exhibited undetectable toxicity to the host cells. Moreover, we reported for the first time the penetration and exfoliation profiles of CD in a three-dimensional organotypic model of human oral epithelial tissues, demonstrating that the extra- and intracellular accumulation of CD-Gu+-AmB effectively resisted the invasion of C. albicans by forming a "shielding" layer throughout the entire tissue. This study establishes a multifunctional CD-based theranostic nanoplatform functioning as a traceable and topically applied antifungal to arm oral epithelia, thereby shedding light on early intervention of mucosal candidiasis for oral and general health.

International audience; Paecilomyces sp. are emerging pathogens in immunocompromised patients. We report here a case of Paecilomyces variotii fungemia, cured with amphotericin and anidulafungin, illustrating difficulties of early diagnosis and therapeutic choice in such rare fungal infection.

International audience; ObjectivesFungal keratitis is rare in France, but could be a severe sight-threatening condition. Here, we aimed to describe the epidemiology of fungal keratitis in Réunion Island.MethodsIn a retrospective study, we analyzed 13 culture-proven keratitis episodes, occurred between January 2013 and July 2017 in the ophthalmology ward of a University Hospital, Saint-Pierre. Twelve isolates were genotyped and antifungal susceptibility testing was performed.ResultsCorneal abrasion caused by vegetable matter was the main predisposing factor. Stromal infiltration was observed in 12 patients. Six patients did not response to medical treatment, requiring surgical care, including two enucleations surgery. Fusarium solani (n = 6) and Fusarium dimerum (n = 4) were the main fungal species involved in fungal keratitis. Clinical failures were more prevalent with F. solani infections. The lowest minimal inhibitory concentrations for Fusarium sp. were observed with voriconazole and amphotericin B.ConclusionIn Reunion Island, the epidemiology of fungal keratitis is characterized by the predominance of Fusarium species, potentially involved in visual loss. This pattern is consistent with the epidemiology usually observed in tropical areas.; La kératite fongique est une maladie rare en France, mais potentiellement grave. Nous avons cherché à décrire l’épidémiologie des kératites fongiques à l’île de la Réunion.MéthodesDans une étude rétrospective, nous avons étudié 13 épisodes de kératite fongique survenus entre janvier 2013 et juillet 2017 dans le service d’ophtalmologie du CHU Réunion, Saint-Pierre. Douze isolats ont été identifiés par biologie moléculaire et la sensibilité aux antifongiques a été déterminée par un antifongigramme.RésultatsUn traumatisme par un végétal était le facteur favorisant le plus fréquent. Une atteinte profonde a été observée chez 12 patients. Six patients n’ont pas répondu au traitement médical de première intention, nécessitant une prise en charge chirurgicale, incluant deux énucléations. Fusarium solani (n = 6) et Fusarium dimerum (n = 4) étaient les principales espèces fongiques impliquées dans les kératites fongiques. Les échecs cliniques étaient plus fréquents avec F. solani. Les concentrations minimales inhibitrices les plus basses vis-à-vis de Fusarium sp. ont été observées pour l’amphotéricine B et le voriconazole.ConclusionÀ l’île de la Réunion, l’épidémiologie des kératites fongiques est caractérisée par la prédominance des infections à Fusarium. Ce schéma correspond à un modèle épidémiologique caractéristique des régions tropicales.

Background Complex cutaneous and muco-cutaneous leishmaniasis (CL and MCL) often requires systemic therapy. Liposomal amphotericin B (L-AmB) has a strong potential for a solid clinical benefit in this indication. Methods We conducted a retrospective analysis of data from a French centralized referral treatment program and from the “LeishMan” European consortium database. All patients with parasitologically proven CL or MCL who received at least one dose of L-AmB were included. Positive outcome was based on ulcer closure as per recent WHO workshop guidelines. Results From 2008 through 2016, 43 travelers returning from 18 countries (Old World n = 28; New World n = 15) were analyzed with a median follow-up duration of 79 days [range 28–803]. Main clinical forms were: localized CL with one or multiple lesions (n = 32; 74%) and MCL (n = 8; 19%). As per published criteria 19 of 41 patients (46%) were cured 90 days after one course of L-AmB. When the following items -improvement before day 90 but no subsequent follow-up, delayed healing (>3 months) and healing after a second course of L-AmB- were included in the definition of cure, 27 of 43 patients (63%) had a positive outcome. Five patients (MCL = 1; CL = 4) experienced a relapse after a median duration of 6 months [range 3–27] post treatment and 53% of patients (23/43) experienced at least one adverse event including severe hypokalaemia and acute cardiac failure (one patient each). In multivariate analysis, tegumentary infection with L. infantum was associated with complete healing after L-AmB therapy (OR 5.8 IC 95% [1.03–32]) while infection with other species had no impact on outcome. Conclusion In conditions close to current medical practice, the therapeutic window of L-AmB was narrow in travellers with CL or MCL, with the possible exception of those infected with L. infantum. Strict follow-up is warranted when using L-AmB in patients with mild disease., Author summary Cutaneous and muco-cutaneous leishmaniasis (CL/MCL) are disfiguring diseases caused by a worldwide distributed parasite called Leishmania and its 20 species. Clinical manifestations span a wide continuum from single nodular lesion to disseminated form with mucosal involvement. Though local treatment with cryotherapy and intralesionnal antimony or topical formulations of paromomycin is generally adequate in most of situations, some patients with complex CL/MCL require systemic therapy. No convenient regimen has been proved to be safe and effective for all infecting species, all clinical forms and all patients (e.g. children, pregnant women, adults with comorbidities or immunosuppression). In this study, the authors examined in returning travelers with CL/MCL the effectiveness of an antifungal agent “liposomal amphotericin B” (L-AmB), which is highly effective in visceral leishmaniasis. Surprisingly, rates of healing were lower than in previous reports in this unselected population that reflects clinical practice in non-endemic countries. The observations also suggest that some Leishmania species (namely, L. infantum) may be more susceptible to L-AmB than others. Occurrence of adverse events should raises the question of the benefit-risk balance of L-AmB in CL/MCL. Careful attention to comorbidities and adoption of strict protocols for administration are pre-requisites for the use of L-AmB in patients with CL/MCL.

International audience; Histoplasmosis caused by Histoplasma capsulatum var. duboisii is a rare disease outside central and western Africa. In Europe, all cases are imported. We report a case of an African histoplasmosis with isolated pulmonary involvement in a non-immunocompromised patient that occurred 40 years after his stay in a disease-endemic area. The patient was given itraconazole. (18)F-fluoro-2-deoxy-d-glucose positron emission tomography-computed tomography was used to assess evolution during treatment. The outcome for the patient was favorable.

We have morphologically characterized Candida tropicalis isolates resistant to amphotericin B (AmB). These isolates present an enlarged cell wall compared to isolates of regular susceptibility. This correlated with higher levels of β-1,3-glucan in the cell wall but not with detectable changes in chitin content. In line with this, AmB-resistant strains showed reduced susceptibility to Congo red. Moreover, mitogen-activated protein kinases (MAPKs) involved in cell integrity were already activated during regular growth in these strains. Finally, we investigated the response elicited by human blood cells and found that AmB-resistant strains induced a stronger proinflammatory response than susceptible strains. In agreement, AmB-resistant strains also induced stronger melanization of Galleria mellonella larvae, indicating that the effect of alterations of the cell wall on the immune response is conserved in different types of hosts. Our results suggest that resistance to AmB is associated with pleiotropic mechanisms that might have important consequences, not only for the efficacy of the treatment but also for the immune response elicited by the host.

Candida albicans can form biofilms that exhibit elevated intrinsic resistance to various antifungal agents, in particular azoles and polyenes. The molecular mechanisms involved in the antifungal resistance of biofilms remain poorly understood. We have used transcript profiling to explore the early transcriptional responses of mature C. albicans biofilms exposed to various antifungal agents. Mature C. albicans biofilms grown under continuous flow were exposed for as long as 2 h to concentrations of fluconazole (FLU), amphotericin B (AMB), and caspofungin (CAS) that, while lethal for planktonic cells, were not lethal for biofilms. Interestingly, FLU-exposed biofilms showed no significant changes in gene expression over the course of the experiment. In AMB-exposed biofilms, 2.7% of the genes showed altered expression, while in CAS-exposed biofilms, 13.0% of the genes had their expression modified. In particular, exposure to CAS resulted in the upregulation of hypha-specific genes known to play a role in biofilm formation, such as ALS3 and HWP1 . There was little overlap between AMB- or CAS-responsive genes in biofilms and those that have been identified as AMB, FLU, or CAS responsive in C. albicans planktonic cultures. These results suggested that the resistance of C. albicans biofilms to azoles or polyenes was due not to the activation of specific mechanisms in response to exposure to these antifungals but rather to the intrinsic properties of the mature biofilms. In this regard, our study led us to observe that AMB physically bound C. albicans biofilms and beta-glucans, which have been proposed to be major constituents of the biofilm extracellular matrix and to prevent azoles from reaching biofilm cells. Thus, enhanced extracellular matrix or beta-glucan synthesis during biofilm growth might prevent antifungals, such as azoles and polyenes, from reaching biofilm cells, thus limiting their toxicity to these cells and the associated transcriptional responses.

International audience; Antifungal prescription remains a challenge in pregnant women because of uncertainties regarding fetal toxicity and altered maternal pharmacokinetic parameters that may affect efficacy or increase maternal and fetal toxicity. We present updated data reviewing the available knowledge and current recommendations regarding antifungal prescription in pregnancy. Amphotericin B remains the first-choice parenteral drug in spite of its well-established toxicity. Topical drugs are used throughout pregnancy because of limited absorption. Recent data have clarified the teratogenic effect of high-dose fluconazole during the first trimester and provided reassuring cumulative data regarding its use at a single low dose in this key period. Recent data have also provided additional safety data on itraconazole and lipidic derivatives of amphotericin B. Regarding newer antifungal drugs, including posaconazole and echinocandins, clinical data are critically needed before considering prescription in pregnancy.

International audience; We have determined the in vitro activity of amphotericin B (AMB) and posaconazole (PSC) against Saksenaea vasiformis using broth microdilution and disk diffusion methods and determined the minimal fungicidal concentration (MFC). PSC was found to have the greatest in vitro activity in all cases and was the most efficacious in prolonging survival and reducing the fungal load in an immunocompetent murine model of disseminated infection caused by four strains of the fungus.

International audience; Objectives: The aim of the study was to describe a new evolutionary form of visceral leishmaniasis observed in immunocompromised patients.Methods: We carried out long-term clinical and biological follow-up of 10 HIV-1/Leishmania-coinfected patients presenting numerous secondary visceral leishmaniasis episodes despite treatment, with the follow-up time ranging from 0.5 to 10 years.Results: Analysis of polymerase chain reaction (PCR) and blood culture results demonstrated continuous multiplication and circulation of parasites despite treatment, both during asymptomatic periods and during secondary visceral leishmaniasis episodes. This condition may be termed 'chronic' because of the presence of relapses over a period of several years and 'active' because of the continuous blood circulation of the parasite.Conclusion: We wish to define 'active chronic visceral leishmaniasis' as a novel nosological entity observed in HIV-1/Leishmania-coinfected patients.

International audience; Until the early 1990s, pentavalent antimony was the only documented first-line drug employed for the treatment of zoonotic visceral leishmaniasis (VL) in the Mediterranean, with reported cure rates exceeding 95% in immunocompetent patients. The emergence of antimony resistance in other endemic settings and the increase in drug options have stimulated re-evaluation of the current therapeutic approaches and outcomes in Mediterranean countries. A scientific consortium ('LeishMed' network) collected updated information from collaborating clinical health centres of 11 endemic countries of Southern Europe, Northern Africa and the Middle East. In contrast with the previous situation, VL is now treated differently in the region, basically through three approaches: (1) In Northern Africa and in part of the Middle East, pentavalent antimony is still the mainstay for therapy, with no alternative drug options for treating relapses; (2) In some European countries and Israel, both pentavalent antimony and lipid-associated amphotericin B (AmB) formulations are used as first-line drugs, although in different patients' categories; (3) In other countries of Europe, mainly liposomal AmB is employed. Importantly, cure rates exhibited by different drugs, including antimonials in areas where they are still in routine use, are similarly high (>/=95%) in immunocompetent patients. Our findings show that antimony resistance is not an emerging problem in the Mediterranean. A country's wealth affects the treatment choice, which represents a balance between drug efficacy, toxicity and cost, and costs associated with patient's care.

International audience; The continuous improvement policy for healthcare quality requires practice evaluation. The principle of a clinical audit is to compare practice to guidelines. Prescription guidelines on antifungal agent use has been available in our hospital since 2003. It was updated in 2005 and 2006. OBJECTIVE: The aim of this study was to assess compliance to guidelines, with an audit of prescriptions: amphotericin B lipid formulation, voriconazole and caspofungin, expensive antifungals concerned by the budget allowance correlated to activity, subject to supplementary reimbursement to the coded Homogeneous Group of Diseases. METHOD: The assessment criteria were: relevance of the indication, absence of a better alternative, complying to recommended dosage, loading dose and timing. This retrospective study dealt with all prescriptions of all departments, from January to May 2007. RESULTS: Hundred and eighteen prescriptions were retrospectively analyzed for 81 patients. The rate of overall conformity was 54%. Antifungal therapy was justified for 113 prescriptions (96%). In 30% of the cases, a more efficient alternative was advised, cheaper or less toxic. The dosage and the charge dosing were right in 92% and 80% of the cases respectively. CONCLUSION: This audit allowed assessing good-use of antifungals. We showed an over-prescription of caspofungin and sometimes insufficient regimen of voriconazole dosages for children. Reporting these audit results and development of new international guidelines stress the need to update local recommendations regularly.

This study describes the interactions between two amphiphilic molecules with antileishmanial activity, amphotericin B (AmB) and miltefosine [hexadecylphosphocholine (HePC)], the latter being effective by the oral route. The effect of HePC on the aggregation state of AmB in aqueous solution and the interactions between the two agents were monitored using absorption spectroscopy and circular dichroism. Structural characterization of the mixed aggregates formed in water by dynamic light scattering (DLS) and cryofracture electron microscopy was performed. At concentrations above its critical micelle concentration, HePC was shown to interact with AmB, leading to an increase in the proportion of AmB in its monomeric form as a result of a micellar solubilization mechanism with a capacity of 26 +/- 3 mmol of AmB solubilized/mol of HePC, that is, nearly 40 molecules of HePC per molecule of AmB in the mixed micelles. These were revealed as individual and spherical aggregates close to 10 nm in diameter by both electron microscopy and DLS. Such a micellar formulation provides a new AmB-based system which might be useful in delivering AmB orally for visceral leishmaniasis bitherapy.

International audience; Antifungals of systemic use for the treatment of invasive fungal infections belong to four main chemical families which have globally three cellular targets in fungal cells: fluorinated pyrimidines act on deoxyribonucleic acid (DNA) replication and protein synthesis; polyenes and azoles are toxic for ergosterol and its biosynthetic pathway; lipopeptides inhibit the synthesis of cell wall beta glucans. The resistance mechanisms that are developed by some fungi begin to be well understood particularly in Candida yeasts. The underlying bases of these mechanisms are either mutations that modify the antifungal target, or that block access to the target, and, on the other hand, the overexpression of genes encoding the target, or some membrane proteins involved in the active efflux of antifungal drugs.

Cryptococcosis is the third most common invasive fungal infection in organ transplant recipients after candidiasis and aspergillosis. It occurs almost exclusively in the late posttransplantation period (>6 months after the initiation of immunosuppression). Subclinical onset of meningitis is the usual clinical presentation. Despite initiation of therapy, the mortality rate associated with this infection in this patient population remains high. To the best of our knowledge, this report describes one of the first cases of a rare entity: a primary cutaneous cryptococcosis in a renal transplant recipient disclosed by skull osteomyelitis and pseudotumoral intracranial extension. Surgical debridement and azole antifungal therapy were performed. Ten months after the onset of treatment, the patient feels good, clinical examination findings are normal, and no sign of evolutive cryptococcosis is noted.

International audience; PURPOSE OF REVIEW: Several lipid-based formulations of the antifungal and antiparasitic drug amphotericin B are now available on the market. The purpose of this review is to assess their efficacy against leishmaniasis in both experimental and clinical settings, and to point out new developments in the formulation of this antibiotic. RECENT FINDINGS: The development of resistance to pentavalent antimony compounds has shifted the emphasis to amphotericin B for the treatment of visceral leishmaniasis in India. Lipid formulations show good efficacy but are expensive. The treatment period with lipid formulations is shorter, however, which reduces hospitalization costs. As a result, in developed countries where these costs are an important proportion of the treatment, lipid formulations are preferred, whereas they remain largely inaccessible in developing countries. Lipid-associated amphotericin B has been found to be effective for secondary prophylaxis in HIV-positive patients, in studies carried out in European countries bordering the Mediterranean. SUMMARY: The reduced toxicity of lipid-based formulations of amphotericin B is no longer in doubt. In India, their efficacy against visceral leishmaniasis and shorter treatment periods compared with the conventional formulation with deoxycholate has to be counter-balanced against the very high cost. By contrast, in developed countries around the Mediterranean, where leishmaniasis occurs mainly in immunocompromised individuals, lipid formulations have become the treatment of choice for visceral disease. The efficacy against cutaneous lesions is variable, however, and in some reports oral miltefosine was active after failure of treatment with amphotericin B.

Insect olfactory receptor neurons (ORNs) grown in primary cultures were studied using the patch-clamp technique in both conventional and amphotericin B perforated whole-cell configurations under voltage-clamp conditions. After 10-24 days in vitro, ORNs had a mean resting potential of -62 mV and an average input resistance of 3.2 GOmega. Five different voltage-dependent ionic currents were isolated: one Na(+), one Ca(2+) and three K(+) currents. The Na(+) current (35-300 pA) activated between -50 and -30 mV and was sensitive to 1 microM tetrodotoxin (TTX). The sustained Ca(2+) current activated between -30 and -20 mV, reached a maximum amplitude at 0 mV (-4.5 +/- 6.0 pA) that increased when Ba(2+) was added to the bath and was blocked by 1 mM Co(2+). Total outward currents were composed of three K(+) currents: a Ca(2+)-activated K(+) current activated between -40 and -30 mV and reached a maximum amplitude at +40 mV (605 +/- 351 pA); a delayed-rectifier K(+) current activated between -30 and -10 mV, had a mean amplitude of 111 +/- 67 pA at +60 mV and was inhibited by 20 mM tetraethylammonium (TEA); and, finally, more than half of ORNs exhibited an A-like current strongly dependent on the holding potential and inhibited by 5 mM 4-aminopyridine (4-AP). Pheromone stimulation evoked inward current as measured by single channel recordings.

International audience; One hundred yeast strains (including 60 Candida albicans) were tested in two laboratories using two different antifungal susceptibility test kits, ATB Fungus and Mycostandard. Tests were carried out under everyday work conditions. Four antifungal agents were compared: amphotericin B, flucytosine, miconazole, and ketoconazole. Results were discrepant in 19.2% (77/400) of cases. Following retesting of discordant cases with both kits, the agreement rate for strain characterization was 95.5%. Few discrepancies were seen with flucytosine. Conflicting results obtained with amphotericin B were due to poor reproducibility of Mycostandard results, especially for species other than C. albicans. In contrast, reproducibility of the ATB Fungus kit was inadequate for miconazole. The rate of discrepant results was greatest for ketoconazole. Intermediate susceptibility was seen more often with ATB Fungus for C. albicans and with Mycostandard for C. glabrata and C. krusei. The lack of reproducibility under routine working conditions should lead gallery manufacturers to strive to achieve clearer readings.