Medical Bacteriology: Gram-Negative and Acid-Fast Bacilli

Vocabulary practice flashcards covering Gram-negative curved rods, non-fermenters, fastidious bacilli, zoonotic bacteria, and acid-fast mycobacteria.

Vibrio cholerae

A curved Gram-negative rod with one flagellum and darting motility that produces cholera toxin, causes rice watery diarrhea, grows in alkaline water, produces yellow colonies on TCBS, is oxidase and indole positive, and ferments sugars except lactose.

Vibrio parahemolyticus / Vulnificus

Vibrio species acquired from raw seafood that cause gastroenteritis.

Campylobacter jejuni

A microaerophilic, capnophilic, and thermophilic curved bacillus with single or two flagella exhibiting darting motility; transmitted through food contaminated with animal stool, it causes bloody diarrhea and can trigger Guillain-Barré syndrome and Reiter's syndrome (reactive arthritis).

Skirrow's medium

A selective culture medium used for isolating Campylobacter jejuni and Helicobacter pylori.

Helicobacter pylori

A microaerophilic, capnophilic bacterium with multiple polar flagella providing corkscrew motility; it is strongly urease-positive (detected by endoscopy, urease tests, and urea breath test) and causes gastritis and ulcers.

Pseudomonas aeruginosa

A non-fermenting Gram-negative rod on TSI that turns MacConkey agar yellow, produces green exopigments on nutrient agar, and is known to cause swimmer's ear and eye infections associated with contact lenses.

Acinetobacter

A multidrug-resistant (MDR) pathogen commonly associated with hospital-acquired infections in the intensive care unit (ICU).

Hemophilus influenzae

A fastidious bacterium that forms smooth, low convex, grayish colonies on chocolate agar supplemented with Factor V and Factor X; possesses six capsule types (with Hib being the most invasive) and causes respiratory infections, epiglottitis, and meningitis.

Hemophilus ducreyi

A sexually transmitted bacterium that causes chancroid, presenting as soft, painful genital ulcers.

Hemophilus aegyptius

A bacterial pathogen that causes mucopurulent conjunctivitis, commonly known as pink eye.

Bordetella pertussis

The causative agent of whooping cough that displays a mercury drop appearance in culture, produces pertussis toxin and tracheal cytotoxin, is treated early with erythromycin, and is prevented by the DPT/DTaP vaccine.

Brucella

A zoonotic, facultative intracellular bacterium that causes undulant fever and is identified via serum agglutination tests (STAT) which can exhibit a prozone phenomenon.

Legionella pneumophila

A bacterium cultured on BCYE agar and transmitted via water aerosols; it causes Pontiac fever (a flu-like illness) and Legionnaires' disease (atypical pneumonia).

Mycobacterium tuberculosis

A lipid-rich acid-fast bacillus detected using ZN stain, LJ medium, Auramine, or MGIT; it causes active or latent tuberculosis, is tested via Tuberculin test or Quantiferon, exhibits MDR/XDR forms, and is targeted by the BCG vaccine.

Non-Tuberculous Mycobacteria

Environmental mycobacteria found in sources such as tap water that cause opportunistic infections in AIDS patients.

Mycobacterium leprae

The causative agent of leprosy, visualized in bundles using modified ZN staining, presenting clinically as either lepromatous or tuberculoid leprosy.