Aspergillus-Antigen Testing:Introduction, Principle, Clinical Significance, and Keynotes

Aspergillus-Antigen Testing-Introduction, Principle, Clinical Significance, and Keynotes

Introduction Aspergillus species, particularly Aspergillus fumigatus, are major causes of invasive aspergillosis (IA), especially in immunocompromised patients, such as those with hematological malignancies, transplant recipients, or those with prolonged neutropenia. Diagnosis of IA is often challenging because clinical symptoms and radiological findings are nonspecific. Aspergillus …

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Yeast Identification by MALDI-TOF (BRUKER): Introduction, Principle, Clinical Significance, and Keynotes

Yeast Identification by MALDI-TOF (BRUKER)- Introduction, Principle, Clinical Significance, and Keynotes

Introduction Yeast infections, particularly those caused by Candida, Cryptococcus, and other opportunistic yeasts, are significant in immunocompromised and oncology patients. Rapid and accurate identification of yeasts is essential for guiding therapy and improving patient outcomes. Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry (MALDI-TOF MS), …

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Yeasts E-Test: Introduction, Principle, Clinical Significance, and Keynotes

Yeasts E-Test- Introduction, Principle, Clinical Significance, and Keynotes

Introduction Yeast infections, particularly caused by Candida and Cryptococcus species, are a major clinical challenge, especially in immunocompromised patients. Rapid and accurate determination of antifungal susceptibility is crucial for guiding therapy. The E-test (Epsilometer test) is a widely used, simple, and reliable method for determining …

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Multiplex PCR Assay-Directly on Blood for Fungi: Introduction, Principle, Clinical Significance, and Keynotes

Introduction Fungal bloodstream infections (fungemia) are life-threatening, especially in immunocompromised and oncology patients. Conventional methods like blood culture are slow, often requiring several days for growth and identification. Multiplex PCR directly on blood offers rapid, sensitive, and simultaneous detection of multiple fungal pathogens without the …

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β-D-Glucan: Introduction, Principle, Clinical Significance, and Keynotes

Introduction β-D-Glucan (BDG) is a polysaccharide component of the fungal cell wall, widely present in species such as Candida, Aspergillus, Fusarium, and Pneumocystis jirovecii. Since it is released into the bloodstream during invasive fungal infections (IFIs), detection of BDG has become a valuable non-culture-based diagnostic …

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Blood Culture–Positive Yeasts: Introduction, Common molds, Comparison, and Keynotes

Gram-positive budding yeast-like cells, oval to elongated, arranged singly, in pairs, and in short pseudohyphae-like forms in Gram staining of culture microscopy at a magnification of 4000X

Introduction Unlike molds, yeasts are the most commonly recovered fungi in blood cultures. Candidemia is among the leading causes of bloodstream infections in immunocompromised and critically ill patients. Yeasts such as Candida, Cryptococcus, and Trichosporon are responsible for significant morbidity and mortality. Blood culture positivity …

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Blood Culture–Positive Molds: Introduction, Common molds, Comparison, and Keynotes

Blood Culture–Positive Molds

Introduction Blood cultures are the cornerstone for diagnosing fungemia, but while yeasts (Candida spp.) are frequently detected, molds are rarely recovered in blood culture systems. This is because most molds (Aspergillus, Mucorales) cause tissue-invasive disease without sustained fungemia. However, certain molds such as Fusarium spp. …

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Fungal Identification by PCR-Sequencing (Sanger): Introduction, Principle, Clinical Significance, and Keynotes

Pure culture of Candida

Introduction Accurate identification of fungi is critical for clinical, environmental, and epidemiological purposes. Traditional culture and morphology-based methods are time-consuming and may misidentify cryptic or closely related species. PCR amplification followed by Sanger sequencing of conserved genetic loci (e.g., ITS, 18S rRNA, 28S rRNA, β-tubulin, …

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