Throat Swab Gram stain: Introduction, Report-Interpretation, Clinical Significance, and Keynotes

Gram positive and Gram negative bacteria in throat swab Gram stain photomicrograph at a magnification of 4000X

Introduction A throat swab Gram stain is a rapid, initial diagnostic test performed on specimens collected from the oropharynx or tonsillar region. It helps to identify bacterial flora, pathogens, and inflammatory response. While culture and molecular methods provide definitive diagnosis, Gram staining offers early guidance …

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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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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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Carbol-Nachtblau Staining of Mycobacteria-Introduction, Principle, Clinical Significance, Advantage, Disadvantage, and Keynotes

Introduction Carbol-Nachtblau (Midnight Blue) staining is a modified acid-fast staining technique used for the visualization of Mycobacteria, particularly Mycobacterium tuberculosis. This method replaces the traditional counterstain (like methylene blue) with Nachtblau, producing a vivid contrast between blue background cells and bright red acid-fast bacilli (AFB), …

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Biphasic Medium in Microbiology: Introduction, Application, Merit, Demerits, and Keynotes

Biphasic Medium having bacterial growth

Introduction A biphasic medium is a culture system that combines both liquid (broth) and solid (agar) phases in the same container (usually a bottle or tube). It is designed to enhance microbial recovery by leveraging the advantages of both media types in one setup. Applications …

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Serratia liquefaciens: Introduction, Morphology, Pathogenicity, Lab Diagnosis, Treatment, Prevention, and Keynotes

Serratia liquefaciens and Klebsiella pneumoniae growth on CLED agar of Urine Culture

Introduction Serratia liquefaciens is a species of Gram-negative, rod-shaped bacteria belonging to the genus Serratia. This bacterium is known for its diverse distribution in various environmental niches, including water, soil, plants, and human-related habitats. It has also been associated with clinical infections in humans, making …

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Ascitic Fluid Culture and Sensitivity: Introduction, Report, Clinical Significance, Common Pathogens, and Keynotes

Introduction Ascitic fluid culture and sensitivity is a medical diagnostic procedure used to identify and analyze bacterial or fungal infections within the peritoneal cavity. The peritoneal cavity is the space within the abdomen that contains various organs such as the liver, intestines, and spleen. Ascitic …

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