Acinetobacter lwoffii: Introduction, Pathogenicity, Lab Diagnosis, Treatment, Prevention, and Keynotes

Acinetobacter lwoffii colony morphology on CLED agar

Introduction Acinetobacter lwoffii is a Gram-negative, strictly aerobic, non-motile, non-fermenting, and oxidase-negative bacterium. It belongs to the genus Acinetobacter within the family Moraxellaceae. Unlike its highly aggressive relative Acinetobacter baumannii, A. lwoffii is generally considered a commensal organism. It regularly lives as normal flora on …

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Pseudomonas putida: Introduction, Morphology, Pathogenicity, Lab Diagnosis, Treatment, and Prevention

Pseudomonas putida colony morphology on blood agar after 48 hours of incubation

Introduction Pseudomonas putida is a versatile, Gram-negative, rod-shaped bacterium primarily known for its bioremediation capabilities but recognized as a rare opportunistic human pathogen. Found globally in soil, water, and plant roots, it thrives in diverse environments due to its unique metabolic endurance. Morphology and Characteristics …

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

Gram-negative rods(GNRs) of Serratia marcescens at a magnification of 1000x with 8x optical zoom

Introduction Morphology Pathogenicity Lab Diagnosis Treatment Prevention Keynotes Further Readings

Sphingomonas paucimobilis-Introduction, Morphology, Pathogenicity, Lab Diagnosis, Treatment, Prevention, and Keynotes

Sphingomonas paucimobilis colony morphology on CLED agar

Introduction Sphingomonas paucimobilis (formerly classified as Pseudomonas paucimobilis) is a strictly aerobic, non-fermenting, Gram-negative bacillus. It is an environmental oligotroph found widely in soil and water systems. It serves as a stealthy opportunistic pathogen in clinical settings. It can survive in nutrient-poor conditions and form …

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Mini-Centrifuge-Introduction, Principle, Handling Procedure, Application, and Keynotes

This image shows a compact benchtop mini-centrifuge with a clear dome lid, designed for quick spin-downs of laboratory microtubes.

Introduction Also known as a microcentrifuge, this compact tool is a staple in biological, clinical, and molecular laboratories. Unlike massive, refrigerated floor models, mini-centrifuges are designed for quick spins. They typically accommodate 0.2 mL to 2.0 mL microcentrifuge tubes and feature fixed-angle rotors that reach …

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Orientia and Rickettsia: Introduction, Comparison, Key Differences, Treatment and Diagnosis

Scrub Typhus (Orientia tsutsugamushi) Rapid Test positive and negative results

Introduction Orientia and Rickettsia are two closely related genera of bacteria within the family Rickettsiaceae. Both are small, gram-negative, obligate intracellular pathogens, meaning they can only grow and replicate inside the living cells of their hosts. While they share many clinical features—such as causing fever, …

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VITEK 2 System: Introduction, Organisms List and Identification Cards, Principle, Identification Procedure, Result-Interpretation, and Keynotes

The image shows a front view of the bioMérieux VITEK 2 Compact, a benchtop automated system designed for rapid microbial identification and antibiotic susceptibility testing in clinical laboratorie

Introduction The VITEK 2 System is an automated microbiology platform designed for the rapid identification (ID) and antimicrobial susceptibility testing (AST) of a wide range of microorganisms. It utilizes miniaturized, closed cards that enhance lab safety and streamline workflow. The VITEK 2 cards are lightweight, …

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Contamination in L-J Media: Introduction, Common Contaminant, Identification clues, Minimization tricks, and Keynotes 

Advanced Fungal Contamination and Decolorization of L-J Medium: Fungal Overgrowth-The slants show dense, white, "cotton-like" mycelial growth. This morphology is a classic indicator of contamination by environmental molds, such as Aspergillus or Penicillium. Media Alteration- There is a total loss of the characteristic malachite green color. The medium has turned pale yellow or colorless, suggesting a significant shift in pH or the enzymatic degradation of the selective agent by the contaminants. Diagnostic Interpretation-The rapid growth of these organisms has completely masked any potential slow-growing Mycobacterium tuberculosis. These cultures are invalid and must be recorded as contaminated.

Introduction Lowenstein-Jensen (L-J) medium is the gold standard for the cultivation of Mycobacterium tuberculosis. However, because it is an egg-based, non-selective (or semi-selective) medium that requires long incubation periods, it is highly susceptible to contamination. L-J medium is rich in nutrients (eggs, glycerol, potato flour), …

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