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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Yeasts-Colorimetric Antifungal Susceptibility Testing: Introduction, Principle, Clinical Significance, and Keynotes

Yeasts-Colorimetric Antifungal Susceptibility Testing-Introduction, Principle, Clinical Significance, and Keynotes

Introduction Yeasts, especially Candida and Cryptococcus species, are frequent causes of opportunistic infections in immunocompromised patients. Determining their antifungal susceptibility is crucial for guiding effective therapy. While broth microdilution methods (CLSI/EUCAST) serve as reference standards, they are labor-intensive and time-consuming. Colorimetric antifungal susceptibility testing systems …

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Fungal Culture of Clinical Samples: Introduction, Principle, Clinical Significance, and Keynotes

Body fluid and sputum for culture

Introduction Fungal culture is the gold standard method for the detection and identification of pathogenic fungi in clinical microbiology. It is essential for diagnosing superficial, subcutaneous, and systemic mycoses. Clinical specimens such as blood, sputum, bronchoalveolar lavage (BAL), urine, cerebrospinal fluid (CSF), skin scrapings, nail …

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Molds-Broth Microdilution Testing (CLSI)-Introduction, Principle, Clinical Significance, and Keynotes

Introduction Invasive mold infections such as those caused by Aspergillus, Fusarium, Scedosporium, and Mucorales present significant clinical challenges, especially in immunocompromised hosts. Mortality rates are high, and empirical antifungal therapy often fails due to intrinsic or acquired resistance. Standardized antifungal susceptibility testing (AFST) is therefore …

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Yeasts-Broth Microdilution Testing (EUCAST): Introduction, Principle, Clinical Significance, and Keynotes

Yeasts-Broth Microdilution Testing (EUCAST) Introduction, Principle, Clinical Significance, and Keynotes

Introduction Fungal infections caused by yeasts, particularly Candida and Cryptococcus species, represent a significant clinical challenge in immunocompromised and critically ill patients. Antifungal susceptibility testing (AFST) is crucial for guiding therapy, particularly in cases of treatment failure or the emergence of resistance. The broth microdilution …

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Penicillium vs Paecilomyces: Introduction, Detailed Comparison, Pathogenicity, Lab Diagnosis, Treatment, Prevention, and Keynotes

Penicillium typical structure in LPCB preparation

Introduction of Penicillium vs Paecilomyces Penicillium is a ubiquitous, saprophytic mold found in soil, air, and decaying organic matter. Known for producing the first antibiotic, penicillin, it is typically non-pathogenic but occasionally causes opportunistic infections in immunocompromised hosts. Paecilomyces (especially P. lilacinus and P. variotii) …

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Fungemia-Introduction, Common Fungi, Clinical Feature, Lab Diagnosis, Treatment, and Prevention

Blood fungal culture bottles containing a biphasic medium used for detecting fungal growth in fungemic patients

Introduction Fungemia refers to the presence of fungi in the bloodstream, indicating systemic fungal infection. Candida species are most commonly responsible, but other yeasts and molds may also invade the bloodstream. Fungemia is a medical emergency, especially in ICU patients, immunocompromised hosts, post-surgical cases, and …

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