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Primary cerebral phaeohyphomycosis is a life-threatening disease caused by neurotropic dematiaceous fungi. At present, there are no consensus guidelines regarding optimal antifungal therapy in such cases. Generally, a combination of antifungal agents is recommended for treatment. However, the activities of antifungal combinations against these fungi have not been investigated. In this study, we evaluated the in vitro activities of 13 double and five triple antifungal combinations against clinical isolates of Cladophialophora bantiana (n = 7), Fonsecaea monophora (n = 2), and Cladosporium cladosporioides (n = 1), using a simplified checkerboard procedure. The minimum inhibitory concentrations (MICs) of nine antifungal drugs were determined by the broth microdilution method, and the interaction between antifungal agents in each combination was assessed by the fractional inhibitory concentration index. Excellent activity was observed for posaconazole and itraconazole. Flucytosine had potent activity against C. bantiana but was ineffective against F. monophora, and C. cladosporioides. The echinocandins demonstrated high MICs for all the isolates. Synergistic interactions were observed for all the double combinations, except when itraconazole was combined with either amphotericin B or flucytosine. The combination of amphotericin B with caspofungin showed synergistic interactions against 40% of the isolates. Antagonism was observed with isavuconazole-flucytosine combination against two C. bantiana isolates. The triple combinations of caspofungin and flucytosine with amphotericin B or posaconazole were synergistic against one isolate of F. monophora. For C. cladosporioides, synergy was observed for the triple combination of amphotericin B with caspofungin and flucytosine. Our results indicate that combination of caspofungin with amphotericin B or a triazole, with or without 5-flucytosine has great potential against neurotropic dematiaceous fungi.IMPORTANCEThis research uses a modified version of the checkerboard assay to standardize the in vitro testing of double and triple combinations of antifungal agents against neurotropic dematiaceous fungi. Antifungal combination therapy is associated with improved outcomes in cerebral phaeohyphomycosis. In this study, we demonstrate that posaconazole is the single most active antifungal drug against this group of fungi. The double combination of amphotericin B with caspofungin or a trizole, and the triple combinations of caspofungin and flucytosine with amphotericin B or posaconazole might hold promise in the treatment of cerebral phaeohyphomycosis. Our findings will guide in developing optimal therapeutic strategies for these refractory infections.
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Antifúngicos , Feohifomicosis Cerebral , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana , Antifúngicos/farmacología , Humanos , Feohifomicosis Cerebral/tratamiento farmacológico , Feohifomicosis Cerebral/microbiología , Ascomicetos/efectos de los fármacos , Cladosporium/efectos de los fármacos , Triazoles/farmacología , Quimioterapia Combinada , Flucitosina/farmacología , Itraconazol/farmacología , Equinocandinas/farmacologíaRESUMEN
Background Ixora coccinea is a medicinal plant with many active constituents that are responsible for wound healing and have anticancer properties. Herbal extracts increase the mechanisms related to wound healing, like blood clotting, fighting infection, and epithelialization. The effect responsible for this property may be the presence of phytoconstituents like flavonoids, polyphenols, and alkaloids. Many researchers have evaluated the wound-healing effect of I. coccinea leaf extract in aqueous methanol. This study aimed to determine the in vitro wound healing and anticancer efficacy of I. coccinea leaf ethyl acetate extract and evaluate the in silico docking of the selected phytoconstituents of I. coccinea in the 2vcj protein. Materials and methods The human dermal fibroblast cell line was used to determine the rates of cell migration and proliferation for evaluating the wound-healing effect of the I. coccinea leaf ethyl acetate fraction. 4',6-diamidino-2-phenylindole (DAPI) fluorescence labeling was used to estimate the rate of cell migration. The one-step TUNEL (TdT-mediated dUTP Nick-End Labeling) in situ apoptosis kit and the annexin V-FITC/7-AAD apoptosis kit were used to perform DNA damage assays in the malignant melanoma cell line. The ethyl acetate fraction of I. coccinea leaves was analyzed for its impact on wound healing markers, including keratin-10, keratin-14, type IV collagen, and α-SMA. Results The wound-healing nature was interesting in the ethyl acetate fraction at doses of 50 µg/mL and 100 µg/mL. Both studies involved in the DNA damage study against malignant melanoma cell lines showed the cleavage of apoptotic cancer cells, which was detected using a fluorescence microscope. When compared with the control, a dose of 100 µg/ml of ethyl acetate fraction from the leaves of I. coccinea showed fibroblast migration of cells into the wound area. The statistical values were considered significant at the level of P < 0.05. An in silico docking study on the 2vcj protein revealed that selected phytoconstituents of I. coccinea resulted in good docking scores to inhibit Hsp90. Conclusion I. coccinea ethyl acetate leaf extract can inhibit the growth of malignant melanoma cell lines and promote wound healing, as shown by the study results. It might be a viable therapeutic modality for skin cancer.
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BACKGROUND: Sudden upsurge in cases of COVID-19 Associated Mucormycosis (CAM) following the second wave of the COVID-19 pandemic was recorded in India. This study describes the clinical characteristics, management and outcomes of CAM cases, and factors associated with mortality. METHODS: Microbiologically confirmed CAM cases were enrolled from April 2021 to September 2021 from ten diverse geographical locations in India. Data were collected using a structured questionnaire and entered into a web portal designed specifically for this investigation. Bivariate analyses and logistic regression were conducted using R version 4.0.2. RESULTS: A total of 336 CAM patients were enrolled; the majority were male (n = 232, 69.1%), literate (n = 261, 77.7%), and employed (n = 224, 66.7%). The commonest presenting symptoms in our cohort of patients were oro-facial and ophthalmological in nature. The median (Interquartile Range; IQR) interval between COVID diagnosis and admission due to mucormycosis was 31 (18, 47) days, whereas the median duration of symptoms of CAM before hospitalization was 10 (5, 20) days. All CAM cases received antifungal treatment, and debridement (either surgical or endoscopic or both) was carried out in the majority of them (326, 97.02%). Twenty-three (6.9%) of the enrolled CAM cases expired. The odds of death in CAM patients increased with an increase in HbA1c level (aOR: 1.34, 95%CI: 1.05, 1.72) following adjustment for age, gender, education and employment status. CONCLUSION: A longer vigil of around 4-6 weeks post-COVID-19 diagnosis is suggested for earlier diagnosis of CAM. Better glycemic control may avert mortality in admitted CAM cases.
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COVID-19 , Mucormicosis , Femenino , Humanos , Masculino , COVID-19/epidemiología , Prueba de COVID-19 , India/epidemiología , Mucormicosis/diagnóstico , Mucormicosis/epidemiología , PandemiasRESUMEN
Objectives This study was aimed to investigate the association between virulence factors and antifungal susceptibility pattern among Aspergillus species. Materials and Methods This study was carried out in the Department of Microbiology, from May 2018 to June 2019. A total of 52 Aspergillus isolates obtained from various clinical samples were speciated based on microscopic identification by lacto phenol cotton blue (LPCB) mount and slide culture technique. The production virulence factors such as biofilm, lipase, phospholipase, amylase, and hemolysin were detected using standard phenotypic methods with Aspergillus niger ATCC (American Type Culture Collection) 6275 as the control strain. Antifungal susceptibility patterns of all Aspergillus isolates to amphotericin B, itraconazole, voriconazole, and posaconazole were evaluated in line with the Clinical Laboratory Standards Institute (CLSI) M38-A2 guidelines. Results The percentage of resistance was the highest in itraconazole (48.08%), followed by amphotericin B (28.85%) and voriconazole (9.62%). All amphotericin B-resistant isolates produced biofilm, itraconazole-resistant isolates exhibited phospholipase activity, and voriconazole-resistant isolates produced biofilm and demonstrated phospholipase and hemolytic activities. Regardless of the virulence factors produced, all isolates were susceptible to posaconazole. Conclusion Understanding the relationship between virulence factors and antifungal resistance aids in the development of new therapeutic approaches involving virulence mechanisms as potential targets for effective antifungal drug development.
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BACKGROUND: Increased occurrence of mucormycosis during the second wave of COVID-19 pandemic in early 2021 in India prompted us to undertake a multi-site case-control investigation. The objectives were to examine the monthly trend of COVID-19 Associated Mucormycosis (CAM) cases among in-patients and to identify factors associated with development of CAM. METHODS: Eleven study sites were involved across India; archived records since 1st January 2021 till 30th September 2021 were used for trend analysis. The cases and controls were enrolled during 15th June 2021 to 30th September 2021. Data were collected using a semi-structured questionnaire. Among 1211 enrolled participants, 336 were CAM cases and 875 were COVID-19 positive non-mucormycosis controls. RESULTS: CAM-case admissions reached their peak in May 2021 like a satellite epidemic after a month of in-patient admission peak recorded due to COVID-19. The odds of developing CAM increased with the history of working in a dusty environment (adjusted odds ratio; aOR 3.24, 95% CI 1.34, 7.82), diabetes mellitus (aOR: 31.83, 95% CI 13.96, 72.63), longer duration of hospital stay (aOR: 1.06, 95% CI 1.02, 1.11) and use of methylprednisolone (aOR: 2.71, 95% CI 1.37, 5.37) following adjustment for age, gender, occupation, education, type of houses used for living, requirement of ventilatory support and route of steroid administration. Higher proportion of CAM cases required supplemental oxygen compared to the controls; use of non-rebreather mask (NRBM) was associated as a protective factor against mucormycosis compared to face masks (aOR: 0.18, 95% CI 0.08, 0.41). Genomic sequencing of archived respiratory samples revealed similar occurrences of Delta and Delta derivates of SARS-CoV-2 infection in both cases and controls. CONCLUSIONS: Appropriate management of hyperglycemia, judicious use of steroids and use of NRBM during oxygen supplementation among COVID-19 patients have the potential to reduce the risk of occurrence of mucormycosis. Avoiding exposure to dusty environment would add to such prevention efforts.
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COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , SARS-CoV-2 , India/epidemiología , Estudios de Casos y ControlesRESUMEN
BACKGROUND: Trichoderma spp. are filamentous fungi causing invasive fungal diseases in patients with haematological malignancies and in peritoneal dialysis patients. OBJECTIVES: To analyse clinical presentation, predisposing factors, treatment and outcome of Trichoderma infections. METHODS: A systematic literature review was conducted for published cases of invasive Trichoderma infection in PubMed until December 2021 and by reviewing the included studies' references. Cases from the FungiScope® registry were added to a combined analysis. RESULTS: We identified 50 invasive infections due to Trichoderma species, including 11 in the FungiScope® registry. The main underlying conditions were haematological malignancies in 19 and continuous ambulatory peritoneal dialysis (CAPD) in 10 cases. The most prevalent infection sites were lung (42%) and peritoneum (22%). Systemic antifungal therapy was administered in 42 cases (84%), mostly amphotericin B (nâ=â27, lipid-based formulation 13/27) and voriconazole in 15 cases (30%). Surgical interventions were performed in 13 cases (26%). Overall mortality was 48% (nâ=â24) and highest for allogeneic HSCT and solid organ transplantation (SOT) recipients [80% (4/5) and 77% (7/9), respectively]. In patients treated with amphotericin B, voriconazole and caspofungin, mortality was 55% (15/27), 46% (7/15) and 28% (2/7), respectively. Three out of four patients treated with a combination therapy of voriconazole and caspofungin survived. CONCLUSIONS: Despite treatment with antifungal therapies and surgery, invasive Trichoderma infections are life-threatening complications in immunocompromised patients, especially after HSCT and SOT. In addition, Trichoderma spp. mainly affect the lungs in patients with haematological malignancies and the peritoneum in CAPD patients.
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Neoplasias Hematológicas , Trichoderma , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Caspofungina , Neoplasias Hematológicas/complicaciones , Humanos , Sistema de Registros , Voriconazol/uso terapéuticoRESUMEN
PURPOSE: Trichosporon species are emerging human pathogens, accounting for the second most common cause of non-candidal mycosis. Rapid and reliable identification of these agents allows a better understanding of their epidemiology and therapeutic management. The Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry (MALDI-TOF MS) technique has the potential to be precise, fast and cost-effective. However, the precision of identification totally depends upon the type of protein extraction method used and embedded database in the system. Our objectives were to standardize the protein extraction technique and expand the present Bruker database by creating an in-house database and validating it with diverse clinical Trichosporon species of Indian origin. METHODS: Two different protein extraction protocols (on-plate and off-plate) were evaluated. The off-plate protocol was finalized for the identification. MALDI TOF MS with the existing Bruker database was evaluated for its ability to identify a total of 79 intergenic spacer 1 (IGS1) gene sequence confirmed clinical isolates of 5 different Trichosporon species. RESULTS: As outcome, off plate protocol yielded higher accuracy (73% on the species level and 95% on the genus level) than on-plate (25% on the genus level) in terms of log scores. The existing database for Trichosporon species was enriched with 28 sequence confirmed isolates, which improved accuracy from 73% to 100% and were identified up to species level with a log score >2.3. CONCLUSIONS: Used with standardized protein-extraction protocol along with an expanded database, MALDI-TOF MS could be a rapid and reliable approach to identify clinical Trichosporon species routinely in the laboratory.
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Micosis , Trichosporon , Humanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Trichosporon/genéticaRESUMEN
Objective The aim of this study was to identify and isolate Trichosporon asahii ( T. asahii ) from clinical samples and to assess the genetic relatedness of the most frequently isolated strains of T. asahii using random amplification of polymorphic DNA (RAPD) primers GAC-1 and M13. Methods All the clinical samples that grew Trichosporon species, identified and confirmed by polymerase chain reaction (PCR) using Trichosporon genus-specific primers, were considered for the study. Confirmation of the species T. asahii was carried out by T. asahii- specific PCR. Fingerprinting of the most frequently isolated T. asahii isolates was carried out by RAPD using random primers GAC-1 and M13. Results Among the 72 clinical isolates of Trichosporon sp. confirmed by Trichosporon -specific PCR, 65 were found to be T. asahii as identified by T. asahii- specific PCR. Fingerprinting of the 65 isolates confirmed as T. asahii using GAC-1 RAPD primer yielded 11 different patterns, whereas that of M13 primer produced only 5 patterns. The pattern I was found to be the most predominant type (29.2%) followed by pattern III (16.9%) by GAC-1 primer. Conclusions This study being the first of its kind in India on strain typing of T. asahii isolates by adopting RAPD analysis throws light on genetic diversity among the T. asahii isolates from clinical samples. Fingerprinting by RAPD primer GAC-1 identified more heterogeneity among the T. asahii isolates than M13.
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A 60-year-old male patient undergoing chemotherapy for multiple myeloma Stage II presented to our hospital with complaints of cough, haemoptysis, fever and loose stools. Sputum sample was sent for fungal culture. Fungal culture on Sabouraud dextrose agar yielded bluish-green velvety growth with orange-to-red diffusible pigment on the reverse. The isolate was identified as Penicillium species, probably Penicillium citrinum or Penicillium pinophilus. As the isolate did not exhibit thermal dimorphism, the possibility of the fungal isolate being Penicillium marneffei was ruled out. The isolate was sent for molecular identification and confirmation, which was identified as P. citrinum. His HIV status was negative. In this case, his immunocompromised state due to multiple myeloma and chemotherapy could have predisposed him to this fungal infection, which is an emerging infection and a rare manifestation seen in high-risk patients receiving targeted therapies.
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Enfermedades Pulmonares Fúngicas/diagnóstico , Mieloma Múltiple , Penicillium , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Mieloma Múltiple/complicacionesRESUMEN
OBJECTIVES: To provide a basis for clinical management decisions in Purpureocillium lilacinum infection. METHODS: Unpublished cases of invasive P. lilacinum infection from the FungiScope® registry and all cases reported in the literature were analysed. RESULTS: We identified 101 cases with invasive P. lilacinum infection. Main predisposing factors were haematological and oncological diseases in 31 cases (30.7%), steroid treatment in 27 cases (26.7%), solid organ transplant in 26 cases (25.7%), and diabetes mellitus in 19 cases (18.8%). The most prevalent infection sites were skin (nâ=â37/101, 36.6%) and lungs (nâ=â26/101, 25.7%). Dissemination occurred in 22 cases (21.8%). Pain and fever were the most frequent symptoms (nâ=â40/101, 39.6% and nâ=â34/101, 33.7%, respectively). Diagnosis was established by culture in 98 cases (97.0%). P. lilacinum caused breakthrough infection in 10 patients (9.9%). Clinical isolates were frequently resistant to amphotericin B, whereas posaconazole and voriconazole showed good in vitro activity. Susceptibility to echinocandins varied considerably. Systemic antifungal treatment was administered in 90 patients (89.1%). Frequently employed antifungals were voriconazole in 51 (56.7%) and itraconazole in 26 patients (28.9%). Amphotericin B treatment was significantly associated with high mortality rates (nâ=â13/33, 39.4%, P = <0.001). Overall mortality was 21.8% (nâ=â22/101) and death was attributed to P. lilacinum infection in 45.5% (nâ=â10/22). CONCLUSIONS: P. lilacinum mainly presents as soft-tissue, pulmonary or disseminated infection in immunocompromised patients. Owing to intrinsic resistance, accurate species identification and susceptibility testing are vital. Outcome is better in patients treated with triazoles compared with amphotericin B formulations.
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Paecilomyces , Anfotericina B , Antifúngicos/uso terapéutico , Humanos , Hypocreales , Pruebas de Sensibilidad Microbiana , VoriconazolRESUMEN
Cryptococcosis is a life-threatening infection caused by Cryptococcus neoformans and C. gattii species complex. In the present study, to understand the molecular epidemiology of 208 clinical isolates of Cryptococcus from different parts of India, multilocus sequence typing (MLST) using ISHAM MLST consensus scheme for C. neoformans/C. gattii species complex was used. MLST analysis yielded a total of 10 Sequence Types (STs)-7 STs for C. neoformans and 3 for C. gattii species complex. The majority of isolates identified as C. neoformans belonged to molecular type VNI with predominant STs 31 and 93. Only 3 isolates of C. gattii species complex were obtained, belonging to ST58 and ST215 of VGI and ST69 of VGIV. Phylogenetic analysis revealed less diversity among the clinical Indian isolates compared to the global MLST database. No association between prevalent STs and HIV status, geographical origin or minimum inhibitory concentration (MIC) could be established.
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Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Genotipo , Humanos , India , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , FilogeniaRESUMEN
Background: Malassezia though known for its cutaneous infections can potentially cause invasion. The skin infections caused by Malassezia have poor patient compliance due to its chronicity and recurrent nature of the disease. There is also a lack of standardised antifungal susceptibility profile for Malassezia due to its complex growth requirement. Objective: This study was performed to understand the epidemiological pattern of disease and to study the antifungal susceptibility testing (AFST) profile so as to choose the appropriate drug/drugs to treat the infections caused by Malassezia. Materials and Methods: Samples were collected and processed, species were identified by conventional method and AFST was done by broth microdilution method. Results: The epidemiological pattern showed adolescent females commonly affected in torso. The most common lesion was pityriasis versicolor. The systemic antifungal of choice was itraconazole with the lowest minimum inhibitory concentration (MIC) of 0.125-1 µg/ml. The best topical drug with the lowest MIC value was clotrimazole 0.03-0.5 µg/ml. Conclusion: AFST is important as it will help the dermatologist to choose the appropriate antifungal agents for the patient and thereby reduce the chronicity of the disease with good patient compliance.
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Antifúngicos/farmacología , Azoles/farmacología , Dermatomicosis/epidemiología , Dermatomicosis/microbiología , Malassezia/efectos de los fármacos , Malassezia/patogenicidad , Adolescente , Adulto , Distribución por Edad , Niño , Femenino , Humanos , Incidencia , Malassezia/clasificación , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Fenotipo , Prevalencia , Distribución por Sexo , Piel/patología , Adulto JovenRESUMEN
BACKGROUND AND AIM: Due to limited data on invasive mould infections (IMIs) in the intensive care units (ICUs) of developing countries, we ascertain epidemiology and management of IMIs at 11 ICUs across India. METHODS: Consecutive patients with proven or probable/putative IMIs were enrolled during the study period. Subjects were categorized into classical (neutropenia, malignancy, transplant recipients on immunosuppression) and non-classical (chronic obstructive pulmonary disease, diabetes, liver disease and glucocorticoids) risk groups. We analyzed the demographic, laboratory variables and outcomes of these patients. RESULTS: 398 patients with IMIs (96 proven, 302 probable) were identified, amounting to a prevalence of 9.5 cases/1000 ICU admissions. The mean⯱â¯SD age of the participants was 45.6⯱â¯21.9â¯years. The mean⯱â¯SD APACHE II score was 14.3⯱â¯11.4. The IMIs were diagnosed at a median of 4â¯days after ICU admission. There were 145 and 253 subjects with classical and non-classical risk groups, respectively. Although Aspergillus spp. were the commonest (82.1%) isolates, Mucorales were detected in 14.4% subjects. A high APACHE II score and IMI due to mucormycosis were significant predictors of mortality. CONCLUSIONS: The study highlights the distinct epidemiology of IMIs in India ICUs with high burden, new susceptible patient groups and considerable number of non-Aspergillus mould infections. [clinicaltrials.gov: NCT02683642].
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Hongos/aislamiento & purificación , Huésped Inmunocomprometido , Aspergilosis Pulmonar/epidemiología , Adulto , Anciano , Comorbilidad , Demografía , Femenino , Humanos , India/epidemiología , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Aspergilosis Pulmonar/microbiología , Aspergilosis Pulmonar/mortalidad , Factores de Riesgo , Factores SocioeconómicosRESUMEN
Post-renal transplant fungal infections continue to be a major cause of mortality and morbidity. Universally reported fungi are Candida, especially Candida albicans, Cryptococcus, Aspergillus, Trichophyton rubrum and Pityriasis versicolor. Here, we report a case of infection caused by a rare fungus Diaporthe. It is an endophyte reported as plant pathogens and infrequently in humans and mammals. The patient was a renal transplant recipient on immunosuppressant. He had hypothyroidism and diagnosed with permanent pacemaker due to a complete heart block. The patient was treated with itraconazole (200 mg) successfully.
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Hipotiroidismo/tratamiento farmacológico , Hipotiroidismo/microbiología , Micosis/tratamiento farmacológico , Micosis/microbiología , Animales , Aspergillus/efectos de los fármacos , Aspergillus/patogenicidad , Candida/efectos de los fármacos , Candida/patogenicidad , Cryptococcus/efectos de los fármacos , Cryptococcus/patogenicidad , Humanos , Inmunosupresores/uso terapéutico , Itraconazol/uso terapéutico , Tiña Versicolor/tratamiento farmacológico , Tiña Versicolor/microbiologíaRESUMEN
BACKGROUND: Invasive infections due to Trichosporon spp. have increased recently and are frequently associated with indwelling medical devices. Such infections which are associated with biofilm formation do not respond to the routinely used antifungal agents and are often persistent, associated with high mortality rate. Various methods have been described by researchers to evaluate and quantify the biofilm formation. AIM: This study was conducted to compare two methods of biofilm production by Trichosporon sp, i.e., test tube method with crystal violet (CV) staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. MATERIALS AND METHODS: Seventy-two clinical isolates of Trichosporon spp. collected from various sources were considered for the study. The identity of all the isolates was genotypically confirmed by Trichosporon-specific polymerase chain reaction (PCR). The isolates were further speciated phenotypically using biochemical profile and growth characteristics which identified the isolates as Trichosporon asahii (64/72), Trichosporon asteroides (5/72), Trichosporon cutaneum (2/72), and Trichosporon mucoides (1/72). Biofilm production was then evaluated and compared by test tube-CV method and MTT assay. RESULTS: All the Trichosporon isolates produced biofilm by MTT assay, whereas only 42 (53.6%) of the isolates were detected to be biofilm producers by CV method. Furthermore, MTT assay could differentiate better between weak and moderate biofilm producers as compared to CV method. CONCLUSION: Hence, MTT assay is a reliable method for quantification of biofilm produced by Trichosporon spp. using 96-well microtiter plate.
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Fusarium is an emerging human opportunistic pathogen of growing importance, especially among immunosuppressed haematology patients due to an increased incidence of disseminated infections over the past two decades. This trend is expected only to continue due to the advances in medical and surgical technologies that will prolong the lives of the severely ill, making these patients susceptible to rare opportunistic infections. Production of mycotoxins, enzymes such as proteases, angio-invasive property and an intrinsically resistant nature, makes this genus very difficult to treat. Fusarium is frequently isolated from the cornea and less commonly from nail, skin, blood, tissue, Continuous Ambulatory Peritoneal Dialysis (CAPD) fluid, urine and pleural fluid. Conventional microscopy establishes the genus, but accurate speciation requires multilocus sequence typing with housekeeping genes such as internal transcribed spacer, translation elongation factor-1α and RPB1 and 2 (largest and second largest subunits of RNA polymerase), for which expansive internet databases exist. Identifying pathogenic species is of epidemiological significance, and the treatment includes immune reconstitution by granulocyte-colony-stimulating factor, granulocyte macrophage-colony-stimulating factor and a combination of the most active species - specific antifungals, typically liposomal amphotericin-B and voriconazole. However, patient outcome is difficult to predict even with in vitro susceptibility with these drugs. Therefore, prevention methods and antifungal prophylaxis have to be taken seriously for these vulnerable patients by vigilant healthcare workers. The current available literature on PubMed and Google Scholar using search terms 'Fusarium', 'opportunistic invasive fungi' and 'invasive fusariosis' was summarised for this review.
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Antifúngicos/uso terapéutico , Infecciones Fúngicas del Ojo/prevención & control , Fusariosis/tratamiento farmacológico , Fusariosis/inmunología , Infecciones Oportunistas/tratamiento farmacológico , Infecciones Oportunistas/inmunología , Anfotericina B/uso terapéutico , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/microbiología , Fusariosis/microbiología , Fusarium/clasificación , Fusarium/genética , Fusarium/inmunología , Humanos , Huésped Inmunocomprometido , Tipificación de Secuencias Multilocus , Infecciones Oportunistas/microbiología , Voriconazol/uso terapéuticoRESUMEN
Availability of molecular methods, gene sequencing, and phylogenetic species recognition have led to rare fungi being recognized as opportunistic pathogens. Fungal keratitis and onychomycosis are fairly common mycoses in the tropics, especially among outdoor workers and enthusiasts. The frequently isolated etiological agents belong to genera Candida, Aspergillus, and Fusarium. Within the genus Fusarium, known to be recalcitrant to prolonged antifungal treatment and associated with poor outcome, members of the Fusarium solani species complex are reported to be most common, followed by members of the Fusarium oxysporum SC and the Fusarium fujikuroi SC (FFSC). Morphological differentiation among the various members is ineffective most times. In the present study, we describe different species of the FFSC isolated from clinical specimen in south India. All twelve isolates were characterized up to species level by nucleic acid sequencing and phylogenetic analysis. The molecular targets chosen were partial regions of the internal transcribed spacer rDNA region, the panfungal marker and translation elongation factor-1α gene, the marker of choice for Fusarium speciation. Phylogenetic analysis was executed using the Molecular Evolutionary Genetics Analysis software (MEGA7). In vitro susceptibility testing against amphotericin B, voriconazole, posaconazole, natamycin, and caspofungin diacetate was performed following the CLSI M38-A2 guidelines for broth microdilution method. The twelve isolates of the FFSC were F. verticillioides (n = 4), F. sacchari (n = 3), F. proliferatum (n = 2), F. thapsinum (n = 1), F. andiyazi (n = 1), and F. pseudocircinatum (n = 1). To the best of our knowledge, this is the first report of F. andiyazi from India and of F. pseudocircinatum as a human pathogen worldwide. Natamycin and voriconazole were found to be most active agents followed by amphotericin B. Elderly outdoor workers figured more among the patients and must be recommended protective eye wear.
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Antifúngicos/farmacología , Fusariosis/microbiología , Fusarium/clasificación , Fusarium/efectos de los fármacos , Variación Genética , Filogenia , Adulto , Análisis por Conglomerados , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Femenino , Fusarium/genética , Fusarium/aislamiento & purificación , Humanos , India , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Factor 1 de Elongación Peptídica/genética , Análisis de Secuencia de ADNRESUMEN
INTRODUCTION: Dermatophytes are a group of fungi which infect keratinized tissues and causes superficial mycoses in humans and animals. The group comprises of three major genera, Trichophyton, Microsporum and Epidermophyton. Among them Trichophyton rubrum is a predominant anthropophilic fungi which causes chronic infections. Although, the infection is superficial and treatable, reinfection/coinfection causes inflation in the treatment cost. Identifying the source and mode of transmission is essential to prevent its transmission. Accurate discrimination is required to understand the clinical (relapse or reinfection) and epidemiological implications of the genetic heterogeneity of this species. Polymorphism in the Non Transcribed Spacer (NTS) region of ribosomal DNA (rDNA) clusters renders an effective way to discriminate strains among T. rubrum. AIM: To carry out the strain typing of the clinical isolates, Trichophyton rubrum using NTS as a molecular marker. MATERIALS AND METHODS: Seventy T.rubrum clinical isolates obtained from April-2011-March 2013, from Sri Ramachandra Medical Centre, Chennai, Tamil Nadu, India, were identified by conventional phenotypic methods and included in this prospective study. The isolates were then subjected to Polymerase Chain Reaction (PCR) targeting two subrepeat elements (SREs), TRS-1 and TRS-2 of the NTS region. RESULTS: Strain-specific polymorphism was observed in both subrepeat loci. Total, nine different strains were obtained on combining both TRS-1 and TRS-2, SREs. CONCLUSION: The outcome has given a strong representation for using NTS region amplification in discriminating the T. rubrum clinical isolates. The method can be adapted as a tool for conducting epidemiology and population based study in T. rubrum infections. This will help in future exploration of the epidemiology of T. rubrum.
RESUMEN
INTRODUCTION: Dermatophytes are keratinophilic fungi causing superficial cutaneous infections that account 20-25% of the global population. As per literature search, there is a dearth in the study on virulence factors of dermatophytes from the Indian sub-continent and moreover the association of the virulence factors and the host tissue in vitro helps in understanding the host-pathogen interaction. AIM: To analyse the enzymatic and non-enzymatic virulence activities of dermatophytes on solid media. MATERIALS AND METHODS: A total of 11 isolates, three standard American Type Culture Collection (ATCC) strains- Trichophyton rubrum- 28188, Trichophyton mentagrophytes- 9533, Trichophyton tonsurans- 28942, one CBS KNAW Fungal Biodiversity Centre strain- Arthroderma grubyi- 243.66, five clinical isolates- T. rubrum, T. mentagrophytes, Trichophyton rubrum var. raubitschekii, Trichophyton interdigitale, Epidermophyton floccosum, and two laboratory isolates - Microsporum gypseum and Microsporum canis were screened for the production of virulence enzymes such as phospholipase, lipase, protease, gelatinase and non-enzyme virulence factors (haemolytic activity) of dermatophytes. The clinical isolates were identified from a tertiary care hospital, Chennai. These dermatophytes were tested upon specific substrates on solid media such as egg yolk, tween 80, bovine serum albumin, gelatin powder and sheep blood respectively. RESULTS: The virulence activity of phospholipase, lipase, protease and gelatinase was observed from all the dermatophyte species. T. rubrum, T. rubrum ATCC strain, T. rubrum var. raubitschekii, T. mentagrophytes, T. mentagrophytes ATCC strain, T. interdigitale and A. grubyi CBS strain produced complete haemolysis, whereas other dermatophytes showed no haemolytic activity. CONCLUSION: Phospholipase, lipase, protease and gelatinase act as enzymatic virulence marker and the T. rubrum complex, T. mentagrophytes complex and A. grubyi showed complete haemolysis and hence they may also act as a non-enzymatic virulence marker for dermatophytes.
RESUMEN
Background & objectives: : Dermatophytes are keratinophilic fungi that infect keratinized tissues of human and animal origin. Trichophyton mentagrophytes is considered to be a species complex composed of several strains, which include both anthropophiles and zoophiles. Accurate discrimination is critical for comprehensive understanding of the clinical and epidemiological implications of the genetic heterogeneity of this complex. Molecular strain typing renders an effective way to discriminate each strain. The objective of the study was to characterize T. mentagrophytes clinical isolates to sub-species level using molecular techniques and non-transcribed spacer (NTS) region as marker. Methods: Sixty four T. mentagrophytes clinical isolates were identified by phenotypic methods. These were subjected to polymerase chain reaction targeting three sub-repeat elements (SREs), TmiS0, TmiS1 and TmiS2 of the NTS region. Sequence analysis of internal transcribed spacer (ITS) region of different types was also done. Results: Strain-specific polymorphism was observed in all three loci. Totally, 13 different PCR types were obtained on combining all the three SREs loci. No variation was observed in the ITS region. Interpretation & conclusions: The study described the usefulness of molecular strain typing technique for the discrimination of the T. mentagrophytes isolates. This will help for the future explorations into the epidemiology of T. mentagrophytes and its complex.