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1.
Rev. Nac. (Itauguá) ; 16(3): 221-228, sep-dec 2024.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1572651

RESUMO

RESUMEN La paracoccidioidomicosis es una micosis profunda sistémica, endémica en algunos países de Latinoamérica, de presentación clínica es de evolución aguda/subaguda, en nuestro país es el principal diagnóstico diferencial de la tuberculosis pulmonar. Se describe el caso clínico de un hombre de 48 años, procedente de zona rural, inmunocompetente, que se presentó clínicamente por dificultad respiratoria, pérdida de peso de forma progresiva y lesiones en mucosas oral; como hallazgos radiológicos presentó infiltrados reticulares bilaterales. Desde el punto de vista micológico se evidenció la presencia del microorganismo en diversas muestras biológicas: biopsias de lesiones orofaríngeas y estudio micológico del esputo. Se realizó tratamiento dirigido con antimicótico intravenoso presentando buena respuesta al mismo con mejoría clínica.


ABSTRACT Paracoccidioidomycosis is a deep systemic mycosis, endemic in some Latin American countries, with an acute/subacute clinical presentation. In our country, it is the main differential diagnosis of pulmonary tuberculosis. We describe the clinical case of a 48-year-old man from a rural area, immunocompetent, who presented clinically with respiratory distress, progressive weight loss and lesions in the oral mucosa; as radiological findings, he presented bilateral reticular infiltrates. From a mycological point of view, the presence of the microorganism was evidenced in various biological samples: biopsies of oropharyngeal lesions and mycological study of sputum. Targeted treatment with intravenous antifungals was performed, presenting a good response to it with clinical improvement.

3.
Future Microbiol ; : 1-14, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39011856

RESUMO

Aim: This work aims to standardize the three-dimensional hydroxyethyl-alginate-gelatin (HAG) scaffold as a model to evaluate Aspergillus fumigatus biofilm and antifungal treatments. Methods: The scaffold was characterized by physical, rheological and microscopic analyses; the antibiofilm action was evaluated by determination of cfu and metabolic activity. Results: The scaffold was non-toxic showing stability in aqueous media, swelling capacity, elasticity and had homogeneously distributed pores averaging 190 µm. The A. fumigatus biofilm established itself very well on the scaffold and treatment with amphotericin B and voriconazole reduced viable cells and metabolic activity. Conclusion: The HAG scaffold proved to be a model to mimic lung parenchyma, suitable for establishing a 3D biofilm culture of A. fumigatus and evaluating the efficacy of antifungals.


[Box: see text].

4.
Microorganisms ; 12(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38930447

RESUMO

Chagas Disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi, affecting 6-8 million people, mainly in Latin America. The medical treatment is based on two compounds, benznidazole and nifurtimox, with limited effectiveness and that produce severe side effects; consequently, there is an urgent need to develop new, safe, and effective drugs. Amphotericin B is the most potent antimycotic known to date. A21 is a derivative of this compound with the property of binding to ergosterol present in cell membranes of some organisms. In the search for a new therapeutic drug against T. cruzi, the objective of this work was to study the in vitro and in vivo effects of A21 derivative on T. cruzi. Our results show that the A21 increased the reactive oxygen species and reduced the mitochondrial membrane potential, affecting the morphology, metabolism, and cell membrane permeability of T. cruzi in vitro. Even more important was finding that in an in vivo murine model of infection, A21 in combination with benznidazole was able to reduce blood parasitemia, diminish the immune inflammatory infiltrate in skeletal muscle and rescue all the mice from death due to a virulent T. cruzi strain.

5.
Future Microbiol ; 19(11): 1027-1040, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38904325

RESUMO

The emergence of fungal pathogens and changes in the epidemiological landscape are prevalent issues in clinical mycology. Reports of resistance to antifungals have been reported. This review aims to evaluate molecular and nonmolecular mechanisms related to antifungal resistance. Mutations in the ERG genes and overexpression of the efflux pump (MDR1, CDR1 and CDR2 genes) were the most reported molecular mechanisms of resistance in clinical isolates, mainly related to Azoles. For echinocandins, a molecular mechanism described was mutation in the FSK genes. Furthermore, nonmolecular virulence factors contributed to therapeutic failure, such as biofilm formation and selective pressure due to previous exposure to antifungals. Thus, there are many public health challenges in treating fungal infections.


[Box: see text].


Assuntos
Antifúngicos , Farmacorresistência Fúngica , Fungos , Micoses , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica/genética , Humanos , Micoses/microbiologia , Micoses/tratamento farmacológico , Micoses/epidemiologia , Fungos/efeitos dos fármacos , Fungos/genética , Fungos/patogenicidade , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Mutação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Azóis/farmacologia , Azóis/uso terapêutico , Testes de Sensibilidade Microbiana , Fatores de Virulência/genética , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico
6.
Rev. Inst. Med. Trop ; 19(1)jun. 2024.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1569563

RESUMO

La anfotericina B liposomal se ha utilizado en reemplazo de la anfotericina B desoxicolato para disminuir sus efectos adversos asociados, especialmente la nefrotoxicidad. Presentamos el caso de un paciente masculino de 47 años, sin enfermedad cardíaca previa, con diagnóstico de leishmaniasis visceral, que presentó miocarditis, rabdomiólisis y polineuropatía periférica posterior al tratamiento con anfotericina B liposomal. Este caso resalta la importancia de considerar los efectos adversos tras la administración de anfotericina B liposomal.


Liposomal amphotericin B has been used to replace amphotericin B deoxycholate to reduce its associated adverse effects, especially nephrotoxicity. We present the case of a 47-year-old male patient without known previous heart disease with a diagnosis of visceral leishmaniasis, who presented myocarditis, rhabdomyolysis and peripheral polyneuropathy after starting treatment with liposomal amphotericin B. This case highlights the importance of other adverse effects to consider, such as cardiotoxicity, related to the administration of liposomal amphotericin B and other effects not previously reported such as peripheral polyneuropathy.

7.
J Fungi (Basel) ; 10(5)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38786699

RESUMO

Fungal infections cause 1.7 million deaths annually, which can be attributed not only to fungus-specific factors, such as antifungal resistance and biofilm formation, but also to drug-related challenges. In this study, the potential of Amphotericin (AmB) loaded polymeric nanoparticles (AmB-NPs) combined with murine monoclonal antibodies (mAbs) (i.e., CC5 and DD11) was investigated as a strategy to overcome these challenges. To achieve this goal, AmB-NPs were prepared by nanoprecipitation using different polymers (polycaprolactone (PCL) and poly(D,L-lactide) (PLA)), followed by comprehensive characterization of their physicochemical properties and in vitro biological performance. The results revealed that AmB-loaded NPs exhibited no cytotoxicity toward mammalian cells (baby hamster kidney cells-BHK and human monocyte cells-THP-1). Conversely, both AmB-NPs demonstrated a cytotoxic effect against C. albicans, C. neoformans, and H. capsulatum throughout the entire evaluated range (from 10 µg/mL to 0.1 µg/mL), with a significant MIC of up to 0.031 µg/mL. Moreover, the combination of AmB-NPs with mAbs markedly intensified antifungal activity, resulting in a synergistic effect that was two to four times greater than that of AmB-NPs alone. These findings suggest that the combination of AmB-NPs with mAbs could be a promising new treatment for fungal infections that is potentially more effective and less toxic than current antifungal treatments.

8.
J Nanobiotechnology ; 22(1): 254, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755625

RESUMO

AIM: The antifungal activity was studied on sessile and persister cells (PCs) of Candida tropicalis biofilms of gold nanoparticles (AuNPs) stabilized with cetyltrimethylammonium bromide (CTAB-AuNPs) and those conjugated with cysteine, in combination with Amphotericin B (AmB). MATERIALS/METHODS: The PC model was used and synergistic activity was tested by the checkerboard assay. Biofilms were studied by crystal violet and scanning electron microscopy. RESULTS/CONCLUSIONS: After the combination of both AuNPs and AmB the biofilm biomass was reduced, with significant differences in architecture being observed with a reduced biofilm matrix. In addition, the CTAB-AuNPs-AmB combination significantly reduced PCs. Understanding how these AuNPs aid in the fight against biofilms and the development of new approaches to eradicate PCs has relevance for chronic infection treatment.


Assuntos
Anfotericina B , Antifúngicos , Biofilmes , Candida tropicalis , Sinergismo Farmacológico , Ouro , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Candida tropicalis/efeitos dos fármacos , Ouro/química , Ouro/farmacologia , Biofilmes/efeitos dos fármacos , Anfotericina B/farmacologia , Anfotericina B/química , Nanopartículas Metálicas/química , Antifúngicos/farmacologia , Antifúngicos/química , Cetrimônio/química , Compostos de Cetrimônio/farmacologia , Compostos de Cetrimônio/química
9.
Biochim Biophys Acta Biomembr ; 1866(5): 184326, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703804

RESUMO

The mechanism of Amphotericin B at the membrane is still subject of debate, with the prevailing hypothesis being the formation of pores. The activity of these pores is influenced by various factors. Recently aggregation in solution and insertion in the membrane had been highlighted as crucial for action of the drug Here we investigated the effect of applied pressure on the activity of Amphotericin B. Our findings demonstrate that applied pressure of 50 mmHg is sufficient to enhance the activity. We interpreted the results as supporting the idea that pressure fractures the membrane and promotes the insertion of the polyene.


Assuntos
Anfotericina B , Pressão , Anfotericina B/farmacologia , Anfotericina B/química , Antifúngicos/farmacologia , Antifúngicos/química
10.
Med Mycol ; 62(7)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38806236

RESUMO

Histoplasmosis presents a substantial clinical challenge globally, with a particular prevalence in South America, especially among patients with concurrent Human Immunodeficiency Virus (HIV) infection. Despite itraconazole's established efficacy, investigating alternative therapeutic approaches remains imperative. This is the largest study in our region to date, assessing the effectiveness of the less explored posaconazole treatment. This observational study, conducted at Fundación Valle del Lili (FVL) from 2016 to 2022, encompassed adults with disseminated histoplasmosis. Patients (n = 31) were treated with liposomal amphotericin B as an initial treatment, followed by consolidation treatment with posaconazole or itraconazole. Patients with single-organ cases, those lacking microbiological diagnosis, those who received initial treatment with antifungals other than liposomal Amphotericin B and those with < 6 months follow-up were excluded (Figure 1). Analyses considered population characteristics, treatments, and outcomes. Patients (average age: 45.6; 58.1% female) had common comorbidities (HIV 38.7%, solid organ transplantation 29% and oncologic disease 12.9%). Lungs (48.4%) and lymph nodes (16.1%) were commonly affected. Biopsy (64.5%) was the primary diagnostic method. Initial treatment with liposomal amphotericin B (100%) was given for 14 days on average. Follow-up indicated 71% completion with 19.4% requiring treatment modifications. Notably, 70.9% completed a posaconazole consolidation regimen over 350 days on average. Drug interactions during consolidation (80.6%) were common. No relapses occurred, and three deaths unrelated to histoplasmosis were reported. Traditionally, itraconazole has been the prevalent initial treatment; however, in our cohort, 55.9% of patients received posaconazole as the primary option. Encouragingly, posaconazole showed favorable tolerance and infection resolution, suggesting its potential as an effective and well-tolerated alternative for consolidation treatment. This finding prompts further exploration of posaconazole, potentially leading to more effective patient care and better outcomes.


Histoplasmosis is a critical concern in South America, notably among human immunodeficiency virus patients, leading to high mortality rates. This study, the largest in our region, investigates the effectiveness of posaconazole as an alternative treatment to itraconazole. The results offer the potential for enhanced patient care and improved outcomes.


Assuntos
Anfotericina B , Antifúngicos , Histoplasmose , Itraconazol , Humanos , Histoplasmose/tratamento farmacológico , Histoplasmose/epidemiologia , Histoplasmose/diagnóstico , Masculino , Feminino , Antifúngicos/uso terapêutico , Pessoa de Meia-Idade , Colômbia/epidemiologia , Adulto , Anfotericina B/uso terapêutico , Itraconazol/uso terapêutico , Triazóis/uso terapêutico , Resultado do Tratamento , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Idoso , Histoplasma/isolamento & purificação , Histoplasma/efeitos dos fármacos
11.
IDCases ; 36: e01948, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681079

RESUMO

Aspergillosis is an infrequent infection in the Central Nervous System with a mortality rate higher than 95 %. Early diagnosis is challenging and crucial. In this report, we present the case of a six-year-old female with an intense headache accompanied by left hemiparesis, gaze deviation, horizontal nystagmus, and vomiting of mucous content on five occasions. After several approaches, a cerebrospinal fluid PCR resulted positive for Aspergillus spp., and then management started with amphotericin B at 2.6 mg/kg/day and was managed to have voriconazole. She survived, and two years after her first hospital admission, she suffered from cerebral aspergillosis sequelae. An area of improvement is the coordination between the request and delivery of studies outside the institution. In this case, the patient´s mother did not report the analysis results on time, delaying the diagnosis.

12.
Acta Trop ; 254: 107189, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522630

RESUMO

Cutaneous leishmaniasis (CL) is a vector-borne disease characterized by skin lesions that can evolve into high-magnitude ulcerated lesions. Thus, this study aimed to develop an innovative nanoemulsion (NE) with clove oil, Poloxamer® 407, and multiple drugs, such as amphotericin B (AmB) and paromomycin (PM), for use in the topical treatment of CL. METHODS: Droplet size, morphology, drug content, stability, in vitro release profile, in vitro cytotoxicity on RAW 264.7 macrophages, and antileishmanial activity using axenic amastigotes of Leishmania amazonensis were assessed for NEs. RESULTS: After optimizing the formulation parameters, such as the concentration of clove oil and drugs, using an experimental design, it was possible to obtain a NE with an average droplet size of 40 nm and a polydispersion index of 0.3, and these parameters were maintained throughout the 365 days. Furthermore, the NE showed stability of AmB and PM content for 180 days under refrigeration (4 °C), presented a pH compatible with the skin, and released modified AmB and PM. NE showed the same toxicity as free AmB and higher toxicity than free PM against RAW 264.7 macrophages. The same activity as free AmB, and higher activity than free PM against amastigotes L. amazonensis. CONCLUSION: It is possible to develop a NE for the treatment of CL; however, complementary studies regarding the antileishmanial activity of NE should be carried out.


Assuntos
Anfotericina B , Antiprotozoários , Emulsões , Leishmaniose Cutânea , Paromomicina , Paromomicina/farmacologia , Paromomicina/administração & dosagem , Anfotericina B/farmacologia , Anfotericina B/administração & dosagem , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Animais , Camundongos , Antiprotozoários/farmacologia , Antiprotozoários/administração & dosagem , Antiprotozoários/química , Células RAW 264.7 , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Leishmania mexicana/efeitos dos fármacos , Óleo de Cravo/farmacologia , Óleo de Cravo/química , Poloxâmero/química , Estabilidade de Medicamentos , Nanopartículas/química
13.
Exp Parasitol ; 260: 108743, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513973

RESUMO

Treatment against leishmaniasis presents problems, mainly due to the toxicity of the drugs, high cost, and the emergence of resistant strains. A previous study showed that two vanillin-derived synthetic molecules, 3s [4-(2-hydroxy-3-(4-octyl-1H-1,2,3-triazol-1-yl)propoxy)-3-methoxybenzaldehyde] and 3t [4-(3-(4-decyl-1H-1,2,3-triazol-1-yl)-2-hydroxypropoxy)-3-methoxybenzaldehyde], presented antileishmanial activity against Leishmania infantum, L. amazonensis, and L. braziliensis species. In the present work, 3s and 3t were evaluated to treat L. amazonensis-infected mice. Molecules were used pure or incorporated into Poloxamer 407-based micelles. In addition, amphotericin B (AmpB) and its liposomal formulation, Ambisome®, were used as control. Animals received the treatment and, one and 30 days after, they were euthanized to evaluate immunological, parasitological, and biochemical parameters. Results showed that the micellar compositions (3s/Mic and 3t/Mic) induced significant reductions in the lesion mean diameter and parasite load in the infected tissue and distinct organs, as well as a specific and significant antileishmanial Th1-type immune response, which was based on significantly higher levels of IFN-γ, IL-12, nitrite, and IgG2a isotype antibodies. Drug controls showed also antileishmanial action; although 3s/Mic and 3t/Mic have presented better and more significant parasitological and immunological data, which were based on significantly higher IFN-γ production and lower parasite burden in treated animals. In addition, significantly lower levels of urea, creatinine, alanine transaminase, and aspartate transaminase were found in mice treated with 3s/Mic and 3t/Mic, when compared to the others. In conclusion, results suggest that 3s/Mic and 3t/Mic could be considered as therapeutic candidates to treat against L. amazonensis infection.


Assuntos
Antiprotozoários , Benzaldeídos , Leishmania mexicana , Camundongos Endogâmicos BALB C , Micelas , Animais , Camundongos , Benzaldeídos/farmacologia , Benzaldeídos/química , Leishmania mexicana/efeitos dos fármacos , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Antiprotozoários/química , Leishmaniose Cutânea/tratamento farmacológico , Feminino , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Poloxâmero/química , Poloxâmero/farmacologia , Masculino , Baço/parasitologia
14.
Clin Ther ; 46(4): 322-337, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403508

RESUMO

PURPOSE: Data on the real-life use of amphotericin B lipid complex (ABLC) compared with other available formulations are limited. This study aimed to evaluate the effectiveness, tolerability, and safety of different amphotericin B (AMB) intravenously administered in the context of hospital practice for the treatment of invasive fungal infections (IFI) and to provide new insights into the profile of ABLC. METHODS: This is a multicenter, retrospective, observational study conducted at 10 tertiary Brazilian hospitals. Patients first exposed to any formulation of AMB for treating endemic and opportunistic IFI who had received at least 2 intravenous doses were screened. Retrospective data (from January 2014 to December 2019) were extracted from the patients' medical records. Clinical parameters were examined pre- and post-treatment to determine effectiveness; acute infusion-related side effects (IRSE) and drug interruption to determine tolerability; and adverse events, toxicity, and treatment interruption were stated to analyze safety. FINDINGS: Overall, 1879 medical records of patients were identified. The median (interquartile rate) duration of treatment was 14 (7-21) days. The overall success rate (95% confidence interval [CI]) was 65% (95% CI 60-65). ABLC proved to be effective among AMB formulations with 59% (95% CI 55.6-62.5) within complete response. This was significantly higher in patients who received the drug for a longer period, ≥4 weeks compared to <1 week treatment (P < 0.001). IRSE was observed in 446 (23.7%) patients. Eight cases (1.4%) of severe IRSE in pediatrics and 14 (1.1%) in adults resulted in treatment discontinuation. Regarding safety, 637 (33.9%) patients presented some alteration in creatinine levels during AMB exposure, and 89 (4.74%) had to interrupt or discontinue the drug within the first 14 days of therapy because of renal dysfunction. Overall mortality was 34%. IMPLICATIONS: ABLC is an effective formulation for the treatment of invasive fungal infections, with few adverse events leading to drug discontinuation or lethal outcomes. Furthermore, this real-life study confirmed the comparative safety of AMB lipid formulations versus AMB deoxycholate.


Assuntos
Anfotericina B , Antifúngicos , Infecções Fúngicas Invasivas , Humanos , Estudos Retrospectivos , Infecções Fúngicas Invasivas/tratamento farmacológico , Anfotericina B/efeitos adversos , Anfotericina B/administração & dosagem , Anfotericina B/uso terapêutico , Masculino , Feminino , Antifúngicos/efeitos adversos , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Pessoa de Meia-Idade , Adulto , Resultado do Tratamento , Idoso , Brasil , Adolescente , Adulto Jovem
15.
J Fungi (Basel) ; 10(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38392794

RESUMO

BACKGROUND: Aspergillus fumigatus is an important concern for immunocompromised individuals, often resulting in severe infections. With the emergence of resistance to azoles, which has been the therapeutic choice for Aspergillus infections, monitoring the resistance of these microorganisms becomes important, including the search for mutations in the cyp51A gene, which is the gene responsible for the mechanism of action of azoles. We conducted a retrospective analysis covering 478 A. fumigatus isolates. METHODS: This comprehensive dataset comprised 415 clinical isolates and 63 isolates from hospital environmental sources. For clinical isolates, they were evaluated in two different periods, from 1998 to 2004 and 2014 to 2021; for environmental strains, one strain was isolated in 1998, and 62 isolates were evaluated in 2015. Our primary objectives were to assess the epidemiological antifungal susceptibility profile; trace the evolution of resistance to azoles, Amphotericin B (AMB), and echinocandins; and monitor cyp51A mutations in resistant strains. We utilized the broth microdilution assay for susceptibility testing, coupled with cyp51A gene sequencing and microsatellite genotyping to evaluate genetic variability among resistant strains. RESULTS: Our findings reveal a progressive increase in Minimum Inhibitory Concentrations (MICs) for azoles and AMB over time. Notably, a discernible trend in cyp51A gene mutations emerged in clinical isolates starting in 2014. Moreover, our study marks a significant discovery as we detected, for the first time, an A. fumigatus isolate carrying the recently identified TR46/F495I mutation within a sample obtained from a hospital environment. The observed cyp51A mutations underscore the ongoing necessity for surveillance, particularly as MICs for various antifungal classes continue to rise. CONCLUSIONS: By conducting resistance surveillance within our institution's culture collection, we successfully identified a novel TR46/F495I mutation in an isolate retrieved from the hospital environment which had been preserved since 1998. Moreover, clinical isolates were found to exhibit TR34/L98H/S297T/F495I mutations. In addition, we observed an increase in MIC patterns for Amphotericin B and azoles, signaling a change in the resistance pattern, emphasizing the urgent need for the development of new antifungal drugs. Our study highlights the importance of continued monitoring and research in understanding the evolving challenges in managing A. fumigatus infections.

16.
Open Forum Infect Dis ; 11(2): ofae047, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38370293

RESUMO

Intra-amniotic infection with Candida species is an uncommon but severe condition with high fetal morbimortality and no established clinical guidelines for its management. We report a Candida albicans intra-amniotic infection diagnosed in a 25-week pregnant woman, successfully treated with high-dose liposomal amphotericin B. Pregnancy was prolonged until 30 weeks, and despite persistently positive Candida cultures in amniotic fluid, a healthy newborn was delivered without evidence of systemic infection. Amphotericin concentration was determined at birth, revealing levels over 30 times higher in mother's and cord blood than in the amniotic fluid, probably explaining the clinical protection despite failure in obtaining fungal clearance.

17.
Pathogens ; 13(2)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38392866

RESUMO

Antifungal therapy, especially with the azoles, could promote the incidence of less susceptible isolates of Cryptococcus neoformans and C. gattii species complexes (SC), mostly in developing countries. Given that these species affect mostly the immunocompromised host, the infections are severe and difficult to treat. This review encompasses the following topics: 1. infecting species and their virulence, 2. treatment, 3. antifungal susceptibility methods and available categorical endpoints, 4. genetic mechanisms of resistance, 5. clinical resistance, 6. fluconazole minimal inhibitory concentrations (MICs), clinical outcome, 7. environmental influences, and 8. the relevance of host factors, including pharmacokinetic/pharmacodynamic (PK/PD) parameters, in predicting the clinical outcome to therapy. As of now, epidemiologic cutoff endpoints (ECVs/ECOFFs) are the most reliable antifungal resistance detectors for these species, as only one clinical breakpoint (amphotericin B and C. neoformans VNI) is available.

18.
Nanomedicine (Lond) ; 19(5): 383-396, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38293893

RESUMO

Aim: To develop nanoemulsions (NEs) loading amphotericin B (AmB) and to evaluate the influence of different excipients on the stability and the supramolecular organization, retention and toxicity of AmB. Materials & methods: The NEs were developed from different oils, surfactants, external media and anionic lipids (disteaoryl phosphatidylglycerol [DSPG] and dioleoyl phosphatidylglycerol [DOPG]). Their impact on the size, pH, zeta potential, AmB encapsulation efficiency, AmB retention and hemolytic potential of the NEs was evaluated. Results & conclusion: The use of soybean oil (lipid matrix), Span 80 (surfactant), phosphate buffer (external phase) and DSPG or DOPG (hydrophobic ion pair) provided better NE stability, higher AmB retention within the NEs and a safer formulation profile in hemolysis tests.


Assuntos
Anfotericina B , Fosfatidilgliceróis , Anfotericina B/toxicidade , Tensoativos , Antifúngicos/química
19.
Antimicrob Agents Chemother ; 68(1): e0096823, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38084953

RESUMO

Antifungal susceptibility testing (AST) is crucial in clinical settings to guide appropriate therapy. Nevertheless, discrepancies between treatment response and some results still persist, particularly in detecting resistance to amphotericin B (AMB) in Clavispora (Candida) lusitaniae. This study aimed to assess the susceptibility patterns of 48 recent isolates of C. lusitaniae to 9 antifungal agents and explore the feasibility of using a CLSI reference-based method to identify AMB resistance. Microdilution techniques revealed a wide range of minimal inhibitory concentration (MIC) values for azole antifungals, while echinocandins and AMB exhibited a narrow range of MIC values, with all strains considered wild-type for the tested polyene and echinocandins. However, when agar diffusion (ellipsometry) was employed for AST, certain strains displayed colonies within the inhibition ellipse, indicating potential resistance. Interestingly, these strains did not respond to AMB treatment and were isolated during AMB treatment (breakthrough). Moreover, the evaluation of AMB minimum fungicidal concentrations (MFCs) indicated that only the strains with colonies inside the ellipse had MFC/MIC ratios ≥ 4, suggesting reduced fungicidal activity. In conclusion, this study confirms the effectiveness of ellipsometry with RPMI-1640 2% glucose agar for detecting AMB resistance in C. lusitaniae. Additionally, the proposed approach of culturing "clear" wells in the microdilution method can aid in uncovering resistant strains. The findings highlight the importance of appropriate AST methods to guide effective treatment strategies for deep-seated candidiasis caused by C. lusitaniae. Further collaborative studies are warranted to validate these findings and improve the detection of AMB clinical resistance.


Assuntos
Anfotericina B , Antifúngicos , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Ágar/farmacologia , Equinocandinas/farmacologia , Testes de Sensibilidade Microbiana
20.
J Fungi (Basel) ; 9(10)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37888212

RESUMO

Sporotrichosis is the most frequent subcutaneous or implantation mycosis in Latin America, and its transmission occurs as a result of traumatic inoculation into the skin by organic matter containing the thermodimorphic fungi of the genus Sporothrix. Although cutaneous forms are more common, another important site is the osteoarticular system, whose hematogenous involvement is commonly associated with disseminated forms, especially in people who have an immunosuppressive condition, such as HIV/AIDS, chronic steroid use, and alcohol abuse. We present two cases of osteoarticular sporotrichosis of the knee caused by Sporothrix brasiliensis and followed up at our institution, with different outcomes. In the cases presented here, aging, anatomical sites, comorbidities, subtherapeutic serum levels, low adherence to treatment, and late diagnosis for different reasons may explain the observed outcomes. Early diagnosis of Sporothrix infection is critical in preventing complications, including death. We also highlight the importance of multidisciplinary follow-up and adherence to treatment for a favorable outcome.

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