Yeasts (Disk Diffusion) Assay: Introduction, Test Requirements, Procedure, Result-Interpretation, and Keynotes

Yeasts (Disk Diffusion) Assay

Introduction Disk diffusion assay is a standardized method used for testing antifungal susceptibility of yeasts, especially Candida spp. It evaluates the inhibitory effect of antifungal agents on yeast growth by measuring the zone of inhibition around drug-impregnated disks placed on inoculated agar. This method is …

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Comparative Microscopy of Candida Species: Introduction, Table, and Keynotes

Chlamydospores of Candida albicans found in direct clinical sample(sputum) KOH mount Microscopy (Mag.1600X)

Introduction The genus Candida comprises a diverse group of opportunistic yeasts frequently isolated from human clinical specimens. Among them, Candida albicans remains the most common cause of infections; however, non-albicans Candida species, such as C. tropicalis, C. glabrata, and C. krusei, are increasingly recognized as important pathogens in immunocompromised patients, …

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Comparative Microscopy of Common Clinical Fungi-Introduction, Table, and Appearance at Different Magnifications

Aspergillus in LPCB tease mount of culture

Introduction Microscopy remains one of the cornerstones of clinical mycology, providing a rapid and inexpensive method for the direct detection and preliminary identification of fungi. Comparative microscopy is particularly valuable in distinguishing the morphological features of common clinical fungi, many of which exhibit overlapping clinical …

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Criteria and Decision Framework for Differentiating True Infection from Colonization or Contamination by Aspergillus niger in Cancer Patients

Aspergillus niger growth on SDA

Evaluate the Clinical Context Sample Collection & Repeatability Microscopy & Direct Detection Quantitative Culture & Sterility of Site Serological & Molecular Evidence Radiological Correlation Practical Interpretation Framework Finding Likely Contaminant Possible Colonizer Likely Pathogen Single isolate from 1 sample ✅ ✅ ❌ Repeated isolation from …

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Diagnostic Challenge: LD Bodies vs Pneumocystis Vs Histoplasma in Giemsa-Stained BAL

Found in Giemsa staining of BAL-Possible pathogen?

Found in Giemsa staining of BAL. Possible pathogen? Morphological Features (Center) Possible Pathogen Supporting Features for Pneumocystis Recommendations Is it possible to be LD bodies? Based on the Giemsa-stained BAL image: The central violet-stained cluster of intracellular forms could resemble Leishman-Donovan (LD) bodies, especially in …

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MDR Candida NGS:Introduction, Principle, Test Requirements, Procedure, Result-Interpretation, Clinical Significance, and Keynotes

MDR Candida NGS:Introduction, Principle, Test Requirements, Procedure, Result-Interpretation, Clinical Significance, and Keynotes

 Introduction of MDR Candida NGS MDR Candida NGS refers to the use of Next-Generation Sequencing for the detection, identification, and resistance gene profiling of multidrug-resistant (MDR) Candida species, such as Candida auris, Candida glabrata, and others resistant to azoles, echinocandins, or polyenes. Next-generation sequencing (NGS) …

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Pneumocystis PCR: Introduction, Principle, Test Requirements, Procedure, Result-Interpretation, Clinical Significance, and Keynotes

Pneumocystis PCR: Introduction, Principle, Test Requirements, Procedure, Result-Interpretation, Clinical Significance, and Keynotes

Introduction Pneumocystis PCR is a molecular diagnostic tool used for the detection of Pneumocystis jirovecii DNA in respiratory specimens, especially in immunocompromised patients suspected of having Pneumocystis pneumonia (PCP).It offers higher sensitivity than traditional staining techniques (e.g., GMS, toluidine blue) and is particularly helpful in …

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Wade-Fite stain:Introduction, Principle, Test Requirements, Staining Procedure, Result Interpretation,and Keynotes

Wade-Fite stain:Introduction, Principle, Test Requirements, Staining Procedure, Result Interpretation,and Keynotes

Introduction The Ziehl-Neelsen stain, also known as the Wade-Fite stain, is a modified acid-fast staining technique specifically used to detect Mycobacterium leprae in tissue sections, particularly skin biopsies. It preserves the lipid-rich capsule of M. leprae, which is essential for its identification. It is a …

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