Fungal keratitis caused by Pseudallescheria boydii: clinical and mycological characteristics

Abstract Background Pseudallescheria keratitis is rare but important type of fungal keratitis because of the inherently resistance of the organism to many existing antifungal agents. Methods Slit-lamp and confocal microscopy were used for clinical examinations. Fungal isolates were identified based on morphological characteristics and DNA sequence of the internal transcribed spacer region (ITS). In vitro antifungal susceptibility testing for fungal isolates was performed according to the Clinical and Laboratory Standards Institute (CLSI, M38-A2). Result All patients had a history of ocular trauma. In clinical examination hypopion were seen in three patients. The main antifungal medications were topical voriconazole. After treatment the visual acuity of all patients improved in 2–3 weeks. Conclusion All four patients of Pseudallescheria keratitis had similar clinical features. Accurate and rapid identification of species should be helpful in treating p. boydii keratitis.

Download Full-text

Clinical Characteristics and Outcomes of Rare Fungal Keratitis Caused by Verticillium dahliae

10.21203/rs.3.rs-260137/v1 ◽

2021 ◽

Author(s):

Qing Huang ◽

Wenlu Zhang ◽

Yu Sun ◽

Xiaofeng Li ◽

Xiaoyu Zhang ◽

...

Keyword(s):

Verticillium Dahliae ◽

Clinical Characteristics ◽

Corneal Ulcer ◽

Antifungal Susceptibility ◽

Corneal Thickness ◽

Fungal Keratitis ◽

Lamellar Keratoplasty ◽

Internal Transcribed Spacer Region ◽

In Vitro Antifungal Susceptibility

Abstract PurposeTo observe clinical characteristics and treatment outcomes of fungal keratitis cause by Verticillium dahliae. MethodsClinical data of 7 patients diagnosed as fungal keratitis cause by V. dahliae were retrospectively analyzed. The clinical manifestations, mycology, in vitro antifungal susceptibility, treatment regimens and prognoses of the patients were evaluated. ResultsAll 7 patients were farm worker, of which 5 cases were caused by plant trauma. The corneal ulcer had a round shape and a relatively limited range with the diameters mainly in the range of 2-7 mm. The stromal infiltration was mild, and had no pseudopodia, mossiness or endothelial plaques. Intact hyphaes were detected in corneal scrapings and confocal microscopy, isolates were identified by morphology and by sequencing the internal transcribed spacer region of ribosomal DNA. In vitro antifungal susceptibility testing showed that the most sensitive antifungal drug was Amphotericin B. In the 6 patients with an ulcer less than 2/3 of the corneal thickness, the ulcer healed after 18 days of antifungal treatment only in one eye. The other five patients underwent corneal ulcer debridement or conjunctival flap covering surgery. The remaining one patient with ulcer depth more than 2/3 of the corneal thickness underwent lamellar keratoplasty. ConclusionFungal keratitis caused by V. dahliae has typical signs of a mild inflammatory response, and is not sensitive to antifungal drugs. It is recommended that patients undergo corneal ulcer debridement as soon as possible to promote rapid healing of the ulcers.

Download Full-text

Neocucurbitaria keratinophila: An emerging opportunistic fungus causing superficial mycosis in Spain

Medical Mycology ◽

10.1093/mmy/myy132 ◽

2018 ◽

Vol 57 (6) ◽

pp. 733-738 ◽

Cited By ~ 1

Author(s):

Nicomedes Valenzuela-Lopez ◽

José F Cano-Lira ◽

Alberto M Stchigel ◽

Olga Rivero-Menendez ◽

Ana Alastruey-Izquierdo ◽

...

Keyword(s):

Rna Polymerase Ii ◽

Internal Transcribed Spacer ◽

Opportunistic Infections ◽

Antifungal Susceptibility ◽

Opportunistic Pathogen ◽

Morphological Characterization ◽

Internal Transcribed Spacer Region ◽

Superficial Mycosis ◽

In Vitro Antifungal Susceptibility

Abstract Although there have been few reports of opportunistic infections (superficial and systemic) caused by coelomycetous fungi, they are becoming more frequent. Neocucurbitaria keratinophila (formerly Pyrenochaeta keratinophila), characterized by producing pycnidial conidiomata and small hyaline conidia, seems to be an emergent opportunistic pathogen in Spain. Since this fungus was first reported from human keratitis, eight strains have been isolates from clinical cases in Spain. This is a retrospective study of these fungal strains, including phenotypic and molecular characterizations, and in vitro antifungal susceptibility assays. These clinical strains were identified by sequencing four phylogenetic markers such as the internal transcribed spacer region (ITS1-5.8S-ITS2) and fragments of the 28S nrRNA (LSU), beta-tubulin (tub2), and RNA polymerase II subunit 2 (rpb2) genes, and by morphological characterization. All the strains tested were susceptible to the majority of antifungals, being isavuconazole the only drug that showed a poor antifungal activity.

Download Full-text

Molecular Epidemiology and Antifungal Susceptibility of Trichophyton Isolates in Greece: Emergence of Terbinafine-Resistant Trichophytonmentagrophytes Type VIII Locally and Globally

Journal of Fungi ◽

10.3390/jof7060419 ◽

2021 ◽

Vol 7 (6) ◽

pp. 419

Author(s):

Maria Siopi ◽

Ioanna Efstathiou ◽

Konstantinos Theodoropoulos ◽

Spyros Pournaras ◽

Joseph Meletiadis

Keyword(s):

Molecular Epidemiology ◽

Antifungal Susceptibility ◽

Reference Method ◽

Cross Resistance ◽

Squalene Epoxidase ◽

In Vitro Susceptibility ◽

Type Viii ◽

In Vitro Antifungal Susceptibility ◽

Resistance Rates

Trichophyton isolates with reduced susceptibility to antifungals are now increasingly reported worldwide. We therefore studied the molecular epidemiology and the in vitro antifungal susceptibility patterns of Greek Trichophyton isolates over the last 10 years with the newly released EUCAST reference method for dermatophytes. Literature was reviewed to assess the global burden of antifungal resistance in Trichophyton spp. The in vitro susceptibility of 112 Trichophyton spp. molecularly identified clinical isolates (70 T. rubrum, 24 T. mentagrophytes, 12 T. interdigitale and 6 T. tonsurans) was tested against terbinafine, itraconazole, voriconazole and amorolfine (EUCAST E.DEF 11.0). Isolates were genotyped based on the internal transcribed spacer (ITS) sequences and the target gene squalene epoxidase (SQLE) was sequenced for isolates with reduced susceptibility to terbinafine. All T. rubrum, T. interdigitale and T. tonsurans isolates were classified as wild-type (WT) to all antifungals, whereas 9/24 (37.5%) T. mentagrophytes strains displayed elevated terbinafine MICs (0.25–8 mg/L) but not to azoles and amorolfine. All T. interdigitale isolates belonged to ITS Type II, while T. mentagrophytes isolates belonged to ITS Type III* (n = 11), VIII (n = 9) and VII (n = 4). All non-WT T. mentagrophytes isolates belonged to Indian Genotype VIII and harbored Leu393Ser (n = 5) and Phe397Leu (n = 4) SQLE mutations. Terbinafine resistance rates ranged globally from 0–44% for T. rubrum and 0–76% for T. interdigitale/T. mentagrophytes with strong endemicity. High incidence (37.5%) of terbinafine non-WT T. mentagrophytes isolates (all belonging to ITS Type VIII) without cross-resistance to other antifungals was found for the first time in Greece. This finding must alarm for susceptibility testing of dermatophytes at a local scale particularly in non-responding dermatophytoses.

Download Full-text

Quantitation of Candida albicans Ergosterol Content Improves the Correlation between In Vitro Antifungal Susceptibility Test Results and In Vivo Outcome after Fluconazole Treatment in a Murine Model of Invasive Candidiasis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.8.2081-2085.2000 ◽

2000 ◽

Vol 44 (8) ◽

pp. 2081-2085 ◽

Cited By ~ 90

Author(s):

Beth A. Arthington-Skaggs ◽

David W. Warnock ◽

Christine J. Morrison

Keyword(s):

Murine Model ◽

Invasive Candidiasis ◽

Clinical Laboratory ◽

Antifungal Susceptibility ◽

Resistant Isolate ◽

National Committee ◽

Ergosterol Content ◽

In Vitro Antifungal Susceptibility

ABSTRACT MIC end point determination for the most commonly prescribed azole antifungal drug, fluconazole, can be complicated by “trailing” growth of the organism during susceptibility testing by the National Committee for Clinical Laboratory Standards approved M27-A broth macrodilution method and its modified broth microdilution format. To address this problem, we previously developed the sterol quantitation method (SQM) for in vitro determination of fluconazole susceptibility, which measures cellular ergosterol content rather than growth inhibition after exposure to fluconazole. To determine if SQM MICs of fluconazole correlated better with in vivo outcome than M27-A MICs, we used a murine model of invasive candidiasis and analyzed the capacity of fluconazole to treat infections caused by C. albicansisolates which were trailers (M27-A MICs at 24 and 48 h, ≤1.0 and ≥64 μg/ml, respectively; SQM MIC, ≤1.0 μg/ml), as well as those which were fluconazole sensitive (M27-A and SQM MIC, ≤1.0 μg/ml) and fluconazole resistant (M27-A MIC, ≥64 μg/ml; SQM MIC, 54 μg/ml). Compared with the untreated controls, fluconazole therapy increased the survival of mice infected with a sensitive isolate and both trailing isolates but did not increase the survival of mice infected with a resistant isolate. These results indicate that the SQM is more predictive of in vivo outcome than the M27-A method for isolates that give unclear MIC end points due to trailing growth in fluconazole.

Download Full-text

Vaginitis Due To Pichia fermentans in a Patient Affected by Endometrial Cancer: A Novel Case Report

Current Women s Health Reviews ◽

10.2174/1573404817666210712214458 ◽

2021 ◽

Vol 17 ◽

Author(s):

Zarifeh Adampour ◽

Malihe Hasanzadeh ◽

Hossein Zarrinfar ◽

Maryam Nakhaei ◽

Monika Novak Babič

Keyword(s):

Endometrial Cancer ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Female Genital Tract ◽

Antifungal Susceptibility Testing ◽

Vein Thrombosis ◽

Microbial Infections ◽

Life Threatening ◽

In Vitro Antifungal Susceptibility

Introduction: Endometrial cancer is one of the most common malignancies of the female genital tract, which can be serious or life-threatening. Microbial infections can be one of the underlying causes of this type of cancer. Case Presentation: The present study describes the isolation of Pichia fermentans (Candida firmentaria var. firmentaria) from the vaginal secretions of a 61-year-old woman affected by endometrial cancer. She reported abdominal pain and vaginal discharge for 3 months, and had a history of diabetes, hypertension, Deep Vein Thrombosis (DVT), and Acute Myeloid Leukemia (AML). The isolated yeast was identified based on nuclear ribosomal internal transcribed spacer (ITS1-ITS2 rDNA) sequence analysis. The in vitro antifungal susceptibility testing showed a higher effect for ketoconazole against P. fermentans than fluconazole, itraconazole and voriconazole. Conclusion: Correct differentiation between P. fermentans and other yeast should be considered. The in vitro antifungal susceptibility testing is recommended for rare yeast, and will help the physicians in providing the best treatment.

Download Full-text